add --force-reinstall --no-deps to torchaudio CUDA install

Move audio validation and saving to thread pool so librosa/ffmpeg decoding
doesn't block the async event loop. Combine validate + load into a single
pass to avoid decoding the file twice. Add 50 MB upload limit and chunked
reads to prevent unbounded memory allocation.

Closes #278

.agents/skills/draft-release-notes/SKILL.md

@@ -0,0 +1,94 @@
+---
+name: draft-release-notes
+description: Use this skill to draft or update the [Unreleased] section of CHANGELOG.md from the actual changes since the last tag. Run this at any point during development to keep a working copy of the release narrative. Does NOT bump versions or create tags.
+---
+
+# Draft Release Notes
+
+## Goal
+
+Update the `[Unreleased]` section at the top of `CHANGELOG.md` with a narrative release story based on the real changes since the last tag. This is a **non-destructive working copy** — run it as many times as you want during development.
+
+## Workflow
+
+1. **Identify the last release tag and gather changes.**
+
+   ```bash
+   LAST_TAG=$(git tag --list "v*" --sort=-v:refname | head -n 1)
+   echo "Last tag: $LAST_TAG"
+   ```
+
+   Then collect raw material from three sources:
+
+   a. **Commit log since last tag:**
+   ```bash
+   git log --oneline "$LAST_TAG"..HEAD
+   ```
+
+   b. **GitHub-generated release notes preview** (PR titles, new contributors):
+   ```bash
+   gh api repos/:owner/:repo/releases/generate-notes \
+     -f tag_name="vNEXT" \
+     -f target_commitish="$(git rev-parse HEAD)" \
+     -f previous_tag_name="$LAST_TAG" \
+     --jq '.body'
+   ```
+
+   c. **Diff stat for theme analysis:**
+   ```bash
+   git diff --stat "$LAST_TAG"..HEAD
+   ```
+
+2. **Draft the release narrative.**
+
+   Write markdown for the `[Unreleased]` section following the format below. Do not include the `## [Unreleased]` heading itself — just the body content.
+
+3. **Update CHANGELOG.md.**
+
+   Replace everything between `## [Unreleased]` and the next `## [` heading with the new draft. Preserve the HTML comment header and all existing release sections below.
+
+   The `[Unreleased]` section must always exist and always be the first section after the header comments.
+
+4. **Do NOT commit, tag, or bump versions.** Just leave the file modified in the working tree.
+
+## Release Story Format
+
+Structure the `[Unreleased]` section like this:
+
+```markdown
+## [Unreleased]
+
+<One strong opening paragraph: what this release is about and why it matters.
+Tie it to concrete shipped changes. No vague hype.>
+
+<One paragraph on major technical shifts, if applicable.>
+
+### <Feature/Theme Group>
+- Bullet points with specifics
+- Reference PRs where available: ([#123](https://github.com/jamiepine/voicebox/pull/123))
+
+### <Another Group>
+- ...
+
+### Bug Fixes
+- ...
+```
+
+### Style Guidelines
+
+- **Factual and specific.** Every claim should trace to a real commit or PR.
+- **Narrative over list.** Lead with paragraphs that tell the story, then support with bullets.
+- **Group by theme, not by commit.** Cluster related changes under descriptive headings.
+- **Reference PRs** where they exist, but don't fabricate them.
+- **Skip trivial chores** (typo fixes, CI tweaks) unless they're the bulk of the release.
+- **Match the voice of existing releases** — look at the v0.2.1 and v0.2.3 entries in CHANGELOG.md for tone reference.
+
+## When There Are No Changes
+
+If `git log "$LAST_TAG"..HEAD` is empty, leave the `[Unreleased]` section empty (just the heading) and tell the user there's nothing to draft.
+
+## Notes
+
+- This skill only touches the `[Unreleased]` section. It never modifies stamped release sections.
+- The agent can be asked to run this skill at any point — mid-feature, before a PR, or right before cutting a release.
+- The `release-bump` skill depends on this draft being up to date before it finalizes.

.agents/skills/release-bump/SKILL.md

@@ -0,0 +1,124 @@
+---
+name: release-bump
+description: Use this skill to finalize a release. It stamps the [Unreleased] changelog section with a version and date, runs bumpversion to update all version files, and creates the release commit and tag. Only run this when you're ready to ship.
+---
+
+# Release Bump
+
+## Goal
+
+Finalize the changelog draft, bump the version across all tracked files, and create a tagged release commit. After this skill runs, the repo has a clean release commit and tag ready to push.
+
+## Prerequisites
+
+- `gh` CLI installed and authenticated (`gh auth status`).
+- `bumpversion` installed (`pip install bumpversion` or available in the project venv).
+- The `[Unreleased]` section of `CHANGELOG.md` should already contain the release narrative. If it's empty or stale, run the `draft-release-notes` skill first.
+
+## Workflow
+
+1. **Verify the working tree is clean** (except `CHANGELOG.md` which may have the draft).
+
+   ```bash
+   git status --porcelain
+   ```
+
+   Only `CHANGELOG.md` (and optionally `.agents/` files) should be modified. If there are other uncommitted changes, stop and ask the user to commit or stash them first.
+
+2. **Determine the bump level.**
+
+   Ask the user if not specified: `patch`, `minor`, or `major`. Check the current version:
+
+   ```bash
+   grep '^current_version' .bumpversion.cfg
+   ```
+
+3. **Stamp the changelog.**
+
+   Read the current `[Unreleased]` content from `CHANGELOG.md`. Compute the new version (based on bump level and current version). Then:
+
+   a. Replace the `## [Unreleased]` section body with an empty placeholder.
+   b. Insert a new stamped section immediately after `## [Unreleased]`:
+
+   ```markdown
+   ## [Unreleased]
+
+   ## [X.Y.Z] - YYYY-MM-DD
+
+   <the content that was in [Unreleased]>
+   ```
+
+   c. Update the reference links at the bottom of the file:
+   - Change the `[Unreleased]` link to compare against the new tag
+   - Add a new link for the new version
+
+   ```markdown
+   [Unreleased]: https://github.com/jamiepine/voicebox/compare/vX.Y.Z...HEAD
+   [X.Y.Z]: https://github.com/jamiepine/voicebox/compare/vPREVIOUS...vX.Y.Z
+   ```
+
+4. **Stage the changelog.**
+
+   ```bash
+   git add CHANGELOG.md
+   ```
+
+5. **Run bumpversion.**
+
+   ```bash
+   bumpversion --allow-dirty <patch|minor|major>
+   ```
+
+   The `--allow-dirty` flag is needed because `CHANGELOG.md` is already staged. bumpversion will:
+   - Update version strings in all tracked files (see `.bumpversion.cfg`)
+   - Create a commit with message `Bump version: X.Y.Z -> A.B.C`
+   - Create a tag `vA.B.C`
+
+   The staged `CHANGELOG.md` will be included in this commit automatically.
+
+6. **Verify results.**
+
+   ```bash
+   git show --name-only --stat HEAD
+   git tag --list "v*" --sort=-v:refname | head -n 5
+   ```
+
+   Confirm the commit contains:
+   - `CHANGELOG.md`
+   - `.bumpversion.cfg`
+   - `tauri/src-tauri/tauri.conf.json`
+   - `tauri/src-tauri/Cargo.toml`
+   - `package.json`
+   - `app/package.json`
+   - `tauri/package.json`
+   - `landing/package.json`
+   - `web/package.json`
+   - `backend/__init__.py`
+
+   Confirm the new tag exists.
+
+7. **Do NOT push** unless the user explicitly asks. Report the tag name and suggest:
+
+   ```
+   Ready to push. When you're ready:
+     git push origin main --follow-tags
+   ```
+
+## Version Calculation Reference
+
+Given current version `X.Y.Z`:
+- `patch` -> `X.Y.(Z+1)`
+- `minor` -> `X.(Y+1).0`
+- `major` -> `(X+1).0.0`
+
+## Error Recovery
+
+- If bumpversion fails, the tag won't exist. Fix the issue and re-run — bumpversion is idempotent as long as the tag doesn't already exist.
+- If you need to undo a release commit (before pushing): `git tag -d vX.Y.Z && git reset --soft HEAD~1`
+- Never amend a release commit that has been pushed.
+
+## Notes
+
+- When the tag is pushed, the release CI (`.github/workflows/release.yml`) automatically extracts the matching version section from `CHANGELOG.md` and uses it as the GitHub Release body. No manual copy-paste needed.
+- The release commit message is controlled by `.bumpversion.cfg` (`Bump version: X.Y.Z -> A.B.C`). Do not override it.
+- If you need to manually update the GitHub Release body after the fact: `gh release edit vX.Y.Z --notes-file <(sed -n '/## \[X.Y.Z\]/,/## \[/p' CHANGELOG.md | head -n -1)`

.bumpversion.cfg

@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 0.2.4
+current_version = 0.2.3
 commit = True
 tag = True
 tag_name = v{new_version}

.github/workflows/release.yml

@@ -123,6 +123,29 @@ jobs:
           p12-file-base64: ${{ secrets.APPLE_CERTIFICATE }}
           p12-password: ${{ secrets.APPLE_CERTIFICATE_PASSWORD }}
 
+      - name: Extract release notes from CHANGELOG.md
+        id: changelog
+        shell: bash
+        run: |
+          # Get the version from the tag (strip leading 'v')
+          VERSION="${GITHUB_REF_NAME#v}"
+
+          # Extract the section for this version from CHANGELOG.md
+          # Matches from "## [X.Y.Z]" until the next "## [" heading
+          NOTES=$(sed -n "/^## \[${VERSION}\]/,/^## \[/{/^## \[${VERSION}\]/d;/^## \[/d;p;}" CHANGELOG.md)
+
+          # Fall back to a placeholder if the version isn't in the changelog
+          if [ -z "$(echo "$NOTES" | tr -d '[:space:]')" ]; then
+            NOTES="See the assets below to download and install this version."
+          fi
+
+          # Use multiline output syntax
+          {
+            echo "notes<<CHANGELOG_EOF"
+            echo "$NOTES"
+            echo "CHANGELOG_EOF"
+          } >> "$GITHUB_OUTPUT"
+
       - uses: tauri-apps/[email protected]
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -139,17 +162,7 @@ jobs:
           projectPath: tauri
           tagName: v__VERSION__
           releaseName: "voicebox v__VERSION__"
-          releaseBody: |
+          releaseBody: ${{ steps.changelog.outputs.notes }}
-            ## What's Changed
-            See the assets below to download and install this version.
-
-            ### Installation
-            - **macOS (Apple Silicon)**: Download the `aarch64.dmg` file - uses MLX for fast native inference
-            - **macOS (Intel)**: Download the `x64.dmg` file - uses PyTorch
-            - **Windows**: Download the `.msi` installer
-            - **Linux**: Compile from source (see README)
-
-            The app includes automatic updates - future updates will be installed automatically.
           releaseDraft: true
           prerelease: false
           args: ${{ matrix.args }}
@@ -176,10 +189,10 @@ jobs:
           pip install -r backend/requirements.txt
           pip install --no-deps chatterbox-tts
 
-      - name: Install PyTorch with CUDA 12.1
+      - name: Install PyTorch with CUDA 12.6
         run: |
-          pip install torch --index-url https://download.pytorch.org/whl/cu121 --force-reinstall --no-deps
+          pip install torch --index-url https://download.pytorch.org/whl/cu126 --force-reinstall --no-deps
-          pip install torchaudio --index-url https://download.pytorch.org/whl/cu121
+          pip install torchaudio --index-url https://download.pytorch.org/whl/cu126 --force-reinstall --no-deps
 
       - name: Verify CUDA support in torch
         run: |

.gitignore

@@ -49,6 +49,8 @@ logs/
 # Generated files
 app/openapi.json
 tauri/src-tauri/binaries/*
+tauri/src-tauri/gen/Assets.car
+tauri/src-tauri/gen/voicebox.icns
 
 # Temporary
 tmp/

CHANGELOG.md

@@ -1,94 +1,437 @@
+<!-- This file is compiled automatically during the release workflow. -->
+<!-- Do not edit manually — your changes will be overwritten. -->
+<!-- To update the draft: ask the agent to use the draft-release-notes skill. -->
+<!-- To finalize a release: ask the agent to use the release-bump skill. -->
+
 # Changelog
 
-All notable changes to Voicebox will be documented in this file.
-
-The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
-and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
-
 ## [Unreleased]
 
-### Fixed
+This release rewrites the backend into a modular architecture, migrates the documentation site to Fumadocs, and ships a batch of bug fixes and UI polish across the stack.
-- **Profile Name Validation** - Added proper validation to prevent duplicate profile names ([#134](https://github.com/jamiepine/voicebox/issues/134))
-  - Users now receive clear error messages when attempting to create or update profiles with duplicate names
-  - Improved error handling in create and update profile API endpoints
-  - Added comprehensive test suite for duplicate name validation
 
-## [0.1.0] - 2026-01-25
+The backend's 3,000-line monolith `main.py` has been decomposed into domain routers, a services layer, and a proper database package. A style guide and ruff configuration now enforce consistency. On the frontend, model loading status is now visible in the UI, effects presets get a dropdown, and several race conditions and accessibility gaps are closed.
 
-### Added
+### Backend Refactor ([#285](https://github.com/jamiepine/voicebox/pull/285))
+- Extracted all routes from `main.py` into 13 domain routers under `backend/routes/` — `main.py` dropped from ~3,100 lines to ~10
+- Moved CRUD and service modules into `backend/services/`, platform detection into `backend/utils/`
+- Split monolithic `database.py` into a `database/` package with separate `models`, `session`, `migrations`, and `seed` modules
+- Added `backend/STYLE_GUIDE.md` and `pyproject.toml` with ruff linting config
+- Removed dead code: unused `_get_cuda_dll_excludes`, stale `studio.py`, `example_usage.py`, old `Makefile`
+- Deduplicated shared logic across TTS backends into `backends/base.py`
+- Improved startup logging with version, platform, data directory, and database stats
+- Fixed startup database session leak — sessions now rollback and close in `finally` block
+- Isolated shutdown unload calls so one backend failure doesn't block the others
+- Handled null duration in `story_items` migration
+- Reject model migration when target is a subdirectory of source cache
 
-#### Core Features
+### Documentation Rewrite ([#288](https://github.com/jamiepine/voicebox/pull/288))
-- **Voice Cloning** - Clone voices from audio samples using Qwen3-TTS (1.7B and 0.6B models)
+- Migrated docs site from Mintlify to Fumadocs (Next.js-based)
-- **Voice Profile Management** - Create, edit, and organize voice profiles with multiple samples
+- Rewrote introduction and root page with content from README
-- **Speech Generation** - Generate high-quality speech from text using cloned voices
+- Added "Edit on GitHub" links and last-updated timestamps on all pages
-- **Generation History** - Track all generations with search and filtering capabilities
+- Generated OpenAPI spec and auto-generated API reference pages
-- **Audio Transcription** - Automatic transcription powered by Whisper
+- Removed stale planning docs (`CUDA_BACKEND_SWAP`, `EXTERNAL_PROVIDERS`, `MLX_AUDIO`, `TTS_PROVIDER_ARCHITECTURE`, etc.)
-- **In-App Recording** - Record audio samples directly in the app with waveform visualization
+- Sidebar groups now expand by default; root redirects to `/docs`
+- Added OG image metadata and `/og` preview page
 
-#### Desktop App
+### UI & Frontend
-- **Tauri Desktop App** - Native desktop application for macOS, Windows, and Linux
+- Added model loading status indicator and effects preset dropdown ([3187344](https://github.com/jamiepine/voicebox/commit/3187344))
-- **Local Server Mode** - Embedded Python server runs automatically
+- Fixed take-label race condition during regeneration
-- **Remote Server Mode** - Connect to a remote Voicebox server on your network
+- Added accessible focus styling to select component
-- **Auto-Updates** - Automatic update notifications and installation
+- Softened select focus indicator opacity
+- Addressed 4 critical and 12 major issues from CodeRabbit review
 
-#### API
+### Platform Fixes
-- **REST API** - Full REST API for voice synthesis and profile management
+- Replaced `netstat` with `TcpStream` + PowerShell for Windows port detection ([#277](https://github.com/jamiepine/voicebox/pull/277))
-- **OpenAPI Documentation** - Interactive API docs at `/docs` endpoint
+- Fixed Docker frontend build and cleaned up Docker docs
-- **Type-Safe Client** - Auto-generated TypeScript client from OpenAPI schema
+- Fixed macOS download links to use `.dmg` instead of `.app.tar.gz`
+- Added dynamic download redirect routes to landing site
 
-#### Technical
+### Release Tooling
-- **Voice Prompt Caching** - Fast regeneration with cached voice prompts
+- Added `draft-release-notes` and `release-bump` agent skills
-- **Multi-Sample Support** - Combine multiple audio samples for better voice quality
+- Wired CI release workflow to extract notes from `CHANGELOG.md` for GitHub Releases
-- **GPU/CPU/MPS Support** - Automatic device detection and optimization
+- Backfilled changelog with all historical releases
-- **Model Management** - Lazy loading and VRAM management
-- **SQLite Database** - Local data persistence
 
-### Technical Details
+## [0.2.3] - 2026-03-15
 
-- Built with Tauri v2 (Rust + React)
+The "it works in dev but not in prod" release. This version fixes a series of PyInstaller bundling issues that prevented model downloading, loading, generation, and progress tracking from working in production builds.
-- FastAPI backend with async Python
+
-- TypeScript frontend with React Query and Zustand
+### Model Downloads Now Actually Work
-- Qwen3-TTS for voice cloning
+
-- Whisper for transcription
+The v0.2.1/v0.2.2 builds could not download or load models that weren't already cached from a dev install. This release fixes the entire chain:
+
+- **Chatterbox, Chatterbox Turbo, and LuxTTS** all download, load, and generate correctly in bundled builds
+- **Real-time download progress** — byte-level progress bars now work in production. The root cause: `huggingface_hub` silently disables tqdm progress bars based on logger level, which prevented our progress tracker from receiving byte updates. We now force-enable the internal counter regardless.
+- **Fixed Python 3.12.0 `code.replace()` bug** — the macOS build was on Python 3.12.0, which has a [known CPython bug](https://github.com/pyinstaller/pyinstaller/issues/7992) that corrupts bytecode when PyInstaller rewrites code objects. This caused `NameError: name 'obj' is not defined` crashes during scipy/torch imports. Upgraded to Python 3.12.13.
+
+### PyInstaller Fixes
+
+- Collect all `inflect` files — `typeguard`'s `@typechecked` decorator calls `inspect.getsource()` at import time, which needs `.py` source files, not just bytecode. Fixes LuxTTS "could not get source code" error.
+- Collect all `perth` files — bundles the pretrained watermark model (`hparams.yaml`, `.pth.tar`) needed by Chatterbox at runtime
+- Collect all `piper_phonemize` files — bundles `espeak-ng-data/` (phoneme tables, language dicts) needed by LuxTTS for text-to-phoneme conversion
+- Set `ESPEAK_DATA_PATH` in frozen builds so the espeak-ng C library finds the bundled data instead of looking at `/usr/share/espeak-ng-data/`
+- Collect all `linacodec` files — fixes `inspect.getsource` error in Vocos codec
+- Collect all `zipvoice` files — fixes source code lookup in LuxTTS voice cloning
+- Copy metadata for `requests`, `transformers`, `huggingface-hub`, `tokenizers`, `safetensors`, `tqdm` — fixes `importlib.metadata` lookups in frozen binary
+- Add hidden imports for `chatterbox`, `chatterbox_turbo`, `luxtts`, `zipvoice` backends
+- Add `multiprocessing.freeze_support()` to fix resource_tracker subprocess crash in frozen binary
+- `--noconsole` now only applied on Windows — macOS/Linux need stdout/stderr for Tauri sidecar log capture
+- Hardened `sys.stdout`/`sys.stderr` devnull redirect to test writability, not just `None` check
+
+### Updater
+
+- Fixed updater artifact generation with `v1Compatible` for `tauri-action` signature files
+- Updated `tauri-action` to v0.6 to fix updater JSON and `.sig` generation
+
+### Other Fixes
+
+- Full traceback logging on all backend model loading errors (was just `str(e)` before)
+
+## [0.2.2] - 2026-03-15
+
+- Fix Chatterbox model support in bundled builds
+- Fix LuxTTS/ZipVoice support in bundled builds
+- Auto-update CUDA binary when app version changes
+- CUDA download progress bar
+- Fix server process staying alive on macOS (SIGHUP handling, watchdog grace period)
+- Hide console window when running CUDA binary on Windows
+
+## [0.2.1] - 2026-03-15
+
+Voicebox v0.1.x was a single-engine voice cloning app built around Qwen3-TTS. v0.2.0 is a ground-up rethink: four TTS engines, 23 languages, paralinguistic emotion controls, a post-processing effects pipeline, unlimited generation length, an async generation queue, and support for every major GPU vendor. Plus Docker.
+
+### New TTS Engines
+
+#### Multi-Engine Architecture
+
+Voicebox now runs **four independent TTS engines** behind a thread-safe per-engine backend registry. Switch engines per-generation from a single dropdown — no restart required.
+
+| Engine                      | Languages | Size    | Key Strengths                                 |
+| --------------------------- | --------- | ------- | --------------------------------------------- |
+| **Qwen3-TTS 1.7B**          | 10        | ~3.5 GB | Highest quality, delivery instructions        |
+| **Qwen3-TTS 0.6B**          | 10        | ~1.2 GB | Lighter, faster variant                       |
+| **LuxTTS**                  | English   | ~300 MB | CPU-friendly, 48 kHz output, 150x realtime    |
+| **Chatterbox Multilingual** | 23        | ~3.2 GB | Broadest language coverage, zero-shot cloning |
+| **Chatterbox Turbo**        | English   | ~1.5 GB | 350M params, low latency, paralinguistic tags |
+
+#### Chatterbox Multilingual — 23 Languages ([#257](https://github.com/jamiepine/voicebox/pull/257))
+
+Zero-shot voice cloning in Arabic, Chinese, Danish, Dutch, English, Finnish, French, German, Greek, Hebrew, Hindi, Italian, Japanese, Korean, Malay, Norwegian, Polish, Portuguese, Russian, Spanish, Swahili, Swedish, and Turkish.
+
+#### LuxTTS — Lightweight English TTS ([#254](https://github.com/jamiepine/voicebox/pull/254))
+
+A fast, CPU-friendly English engine. ~300 MB download, 48 kHz output, runs at 150x realtime on CPU.
+
+#### Chatterbox Turbo — Expressive English ([#258](https://github.com/jamiepine/voicebox/pull/258))
+
+A fast 350M-parameter English model with inline paralinguistic tags.
+
+#### Paralinguistic Tags Autocomplete ([#265](https://github.com/jamiepine/voicebox/pull/265))
+
+Type `/` in the text input with Chatterbox Turbo selected to open an autocomplete for **9 expressive tags**: `[laugh]` `[chuckle]` `[gasp]` `[cough]` `[sigh]` `[groan]` `[sniff]` `[shush]` `[clear throat]`
+
+### Generation
+
+#### Unlimited Generation Length — Auto-Chunking ([#266](https://github.com/jamiepine/voicebox/pull/266))
+
+Long text is now automatically split at sentence boundaries, generated per-chunk, and crossfaded back together. Engine-agnostic.
+
+- Auto-chunking limit slider — 100–5,000 chars (default 800)
+- Crossfade slider — 0–200ms (default 50ms)
+- Max text length raised to 50,000 characters
+- Smart splitting respects abbreviations, CJK punctuation, and `[tags]`
+
+#### Asynchronous Generation Queue ([#269](https://github.com/jamiepine/voicebox/pull/269))
+
+Generation is now fully non-blocking. Serial execution queue prevents GPU contention. Real-time SSE status streaming.
+
+#### Generation Versions
+
+Every generation now supports multiple versions with provenance tracking — original, effects versions, takes, source tracking, version pinning in stories, and favorites.
+
+### Post-Processing Effects ([#271](https://github.com/jamiepine/voicebox/pull/271))
+
+A full audio effects system powered by Spotify's `pedalboard` library: Pitch Shift, Reverb, Delay, Chorus/Flanger, Compressor, Gain, High-Pass Filter, Low-Pass Filter. 4 built-in presets, custom presets, per-profile default effects, and live preview.
 
 ### Platform Support
 
-- macOS (Apple Silicon and Intel)
+- **Windows Support** ([#272](https://github.com/jamiepine/voicebox/pull/272)) — Full Windows support with CUDA GPU detection
-- Windows
+- **Linux** ([#262](https://github.com/jamiepine/voicebox/pull/262)) — AMD ROCm, NVIDIA GBM fix, WebKitGTK mic access (build from source)
-- Linux (AppImage)
+- **NVIDIA CUDA Backend Swap** ([#252](https://github.com/jamiepine/voicebox/pull/252)) — Download and swap in CUDA backend from within the app
+- **Intel Arc (XPU) and DirectML** — PyTorch backend supports Intel Arc and DirectML
+- **Docker + Web Deployment** ([#161](https://github.com/jamiepine/voicebox/pull/161)) — 3-stage build, non-root runtime, health checks
+- **Whisper Turbo** — Added `openai/whisper-large-v3-turbo` as a transcription model option
 
----
+### Model Management ([#268](https://github.com/jamiepine/voicebox/pull/268))
 
-## [Unreleased]
+Per-model unload, custom models directory, model folder migration, download cancel/clear UI ([#238](https://github.com/jamiepine/voicebox/pull/238)), restructured settings UI.
 
-### Fixed
+### Security & Reliability
-- Audio export failing when Tauri save dialog returns object instead of string path
-- OpenAPI client generator script now documents the local backend port and avoids an unused loop variable warning
 
-### Added
+- CORS hardening ([#88](https://github.com/jamiepine/voicebox/pull/88))
-- **Makefile** - Comprehensive development workflow automation with commands for setup, development, building, testing, and code quality checks
+- Network access toggle ([#133](https://github.com/jamiepine/voicebox/pull/133))
-  - Includes Python version detection and compatibility warnings
+- Offline crash fix ([#152](https://github.com/jamiepine/voicebox/pull/152))
-  - Self-documenting help system with `make help`
+- Atomic audio saves ([#263](https://github.com/jamiepine/voicebox/pull/263))
-  - Colored output for better readability
+- Filesystem health endpoint
-  - Supports parallel development server execution
+- Chatterbox float64 dtype fix ([#264](https://github.com/jamiepine/voicebox/pull/264))
 
-### Changed
+### Accessibility ([#243](https://github.com/jamiepine/voicebox/pull/243))
-- **README** - Added Makefile reference and updated Quick Start with Makefile-based setup instructions alongside manual setup
 
----
+Screen reader support, keyboard navigation, state-aware `aria-label` attributes on all interactive controls.
 
-## [Unreleased - Planned]
+### UI Polish
 
-### Planned
+- Redesigned landing page ([#274](https://github.com/jamiepine/voicebox/pull/274))
-- Real-time streaming synthesis
+- Voices tab overhaul with inline inspector
-- Conversation mode with multiple speakers
+- Responsive layout improvements
-- Voice effects (pitch shift, reverb, M3GAN-style)
+- Duplicate profile name validation ([#175](https://github.com/jamiepine/voicebox/pull/175))
-- Timeline-based audio editor
-- Additional voice models (XTTS, Bark)
-- Voice design from text descriptions
-- Project system for saving sessions
-- Plugin architecture
 
----
+### Community Contributors
 
+[@haosenwang1018](https://github.com/haosenwang1018), [@Balneario-de-Cofrentes](https://github.com/Balneario-de-Cofrentes), [@ageofalgo](https://github.com/ageofalgo), [@mikeswann](https://github.com/mikeswann), [@rayl15](https://github.com/rayl15), [@mpecanha](https://github.com/mpecanha), [@ways2read](https://github.com/ways2read), [@ieguiguren](https://github.com/ieguiguren), [@Vaibhavee89](https://github.com/Vaibhavee89), [@pandego](https://github.com/pandego), [@luminest-llc](https://github.com/luminest-llc)
+
+## [0.1.13] - 2026-02-23
+
+### Stability and reliability
+
+- [#95](https://github.com/jamiepine/voicebox/pull/95) Fix: selecting 0.6B model still downloads and uses 1.7B
+- [#93](https://github.com/jamiepine/voicebox/pull/93) fix(mlx): bundle native libs and broaden error handling for Apple Silicon
+- [#79](https://github.com/jamiepine/voicebox/pull/79) fix: handle non-ASCII filenames in Content-Disposition headers
+- [#78](https://github.com/jamiepine/voicebox/pull/78) fix: guard getUserMedia call against undefined mediaDevices in non-secure contexts
+- [#77](https://github.com/jamiepine/voicebox/pull/77) fix: await for confirmation before deleting voices and channels
+- [#128](https://github.com/jamiepine/voicebox/pull/128) fix: resolve multiple issues (#96, #119, #111, #108, #121, #125, #127)
+- [#40](https://github.com/jamiepine/voicebox/pull/40) Fix: audio export path resolution
+
+### Build and packaging
+
+- [#122](https://github.com/jamiepine/voicebox/pull/122) fix(web): add @tailwindcss/vite plugin to web config
+- [#126](https://github.com/jamiepine/voicebox/pull/126) Create requirements.txt
+
+### UX and docs
+
+- [#44](https://github.com/jamiepine/voicebox/pull/44) Enhances floating generate box UX
+- [#57](https://github.com/jamiepine/voicebox/pull/57) chore: updates repo URL in README
+- [#146](https://github.com/jamiepine/voicebox/pull/146) Add Spacebot banner to landing page
+- [#1](https://github.com/jamiepine/voicebox/pull/1) Improvements
+
+## [0.1.12] - 2026-01-31
+
+### Model Download UX Overhaul
+
+- Real-time download progress tracking with accurate percentage and speed info
+- No more downloading notifications during generation even when its not downloading
+- Better error handling and status reporting throughout the download process
+
+### Other Improvements
+
+- Enhanced health check endpoint with GPU type information
+- Improved model caching verification
+- More reliable SSE progress updates
+- Actual update notifications — no need to manually check in settings anymore
+
+## [0.1.11] - 2026-01-30
+
+- Fixed transcriptions on MLX
+- Fixed model download progress (finally)
+
+## [0.1.10] - 2026-01-30
+
+### Faster generation on Apple Silicon
+
+Massive speed gains, from around 20s per generation to 2-3s. Added native MLX backend support for Apple Silicon, providing significantly faster TTS and STT generation on M-series macOS machines.
+
+- **MLX Backend** — New backend implementation optimized for Apple Silicon using MLX framework
+- **Dynamic Backend Selection** — Automatically detects platform and selects between MLX (macOS) and PyTorch (other platforms)
+- Refactored TTS and STT logic into modular backend implementations
+- Updated build process to include MLX-specific dependencies for macOS builds
+
+## [0.1.9] - 2026-01-30
+
+### Improved voice profile creation flow
+
+- Voice create drafts: No longer lose work if you close the modal
+- Fixed whisper only transcribing English or Chinese, now has support for all languages
+
+### Improved Stories editor
+
+- Added spacebar for play/pause
+- Timeline now auto-scrolls to follow playhead during playback
+- Fixed misalignment of the items with mouse when picking up
+- Fixed hitbox for selecting an item
+- Fixed playhead jumping forward when pressing play
+
+### Generation box improvements
+
+- Instruct mode no longer wipes prompt text
+- Improved UI cleanliness
+
+### Misc
+
+- Fixed "Model downloading" toast during generation when model is already downloaded
+
+## [0.1.8] - 2026-01-29
+
+### Model Download Timeout Issues
+
+Fixed critical issue where model downloads would fail with "Failed to fetch" errors on Windows. Refactored download endpoints to return immediately and continue downloads in background.
+
+### Cross-Platform Cache Path Issues
+
+Fixed hardcoded `~/.cache/huggingface/hub` paths that don't work on Windows. All cache paths now use `hf_constants.HF_HUB_CACHE` for proper cross-platform support.
+
+### Windows Process Management
+
+- Added `/shutdown` endpoint for graceful server shutdown on Windows
+- Added `gpu_type` field to health check response
+
+## [0.1.7] - 2026-01-29
+
+- Trim and split audio clips in Story Editor
+- Auto-activation of stories in Story Editor with visible playhead
+- Conditional auto-play support in AudioPlayer for better user control
+- Refactored audio loading across HistoryTable, SampleList, and generation forms
+- Audio now only auto-plays when explicitly intended, preventing unexpected playback
+
+## [0.1.6] - 2026-01-29
+
+### Introducing Stories
+
+A full voice editor for composing podcasts and generated conversations.
+
+- **Stories Editor** — Create multi-voice narratives, podcasts, or conversations with a timeline-based editor
+- Compose tracks with different voices
+- Edit and arrange audio segments inline
+- Build generated conversations with multiple participants
+- **Improved Voice Generation UI** — Auto-resizing input, default voice selection, better layout
+- **Track Editor Integration** — Inline track editing within story items
+
+## [0.1.5] - 2026-01-28
+
+Fixed recording length limit at 0:29 to auto stop instead of passing the limit and getting an error, which would cause users to lose their recording.
+
+## [0.1.4] - 2026-01-28
+
+- Audio channel management system
+- Native audio playback handling in AudioPlayer component
+- Refactored ConnectionForm and Checkbox components
+- Improved layout consistency and responsiveness
+- Added safe area constants for better responsive design
+
+## [0.1.3] - 2026-01-27
+
+- Improved the generate textbox
+- Maybe fixed Windows autoupdate restarting entire computer
+
+## [0.1.2] - 2026-01-27
+
+### Audio Capture & Format Conversion
+
+- Added audio format conversion util
+- Enhanced system audio capture on macOS and Windows
+- Improved audio recording hooks
+- Added audio input entitlement for macOS
+- Added audio capture tests
+
+### Update System
+
+- Enhanced auto-updater functionality and update status display
+
+## [0.1.1] - 2026-01-27
+
+### Platform Support
+
+- **macOS Audio Capture** — Native audio capture support for sample creation
+- **Windows Audio Capture** — WASAPI implementation with improved thread safety
+- **Linux Support** — Temporarily removed builds due to runner disk space constraints
+
+### Audio Features
+
+- Play/pause for audio samples across all components
+- Three new sample components: Recording, System capture, Upload with drag-and-drop
+- Audio validation, error handling, and consistent cleanup
+
+### Voice Profile Management
+
+- Profile import with file size validation (100MB limit)
+- Enhanced profile form with new audio sample components
+- Drag-and-drop support for audio file uploads
+
+### Server Management
+
+- Changed default URL from `localhost:8000` to `127.0.0.1:17493`
+- Server reuse logic, "keep server running" preference, orphaned process handling
+
+### Build & Release
+
+- Added `.bumpversion.cfg` for automated version management
+- Enhanced icon generation script for multi-size Windows icons
+
+### Bug Fixes
+
+- Fixed date formatting for timezone-less date strings
+- Fixed getLatestRelease file filtering
+- Improved audio duration metadata on Windows
+
+## [0.1.0] - 2026-01-27
+
+The first public release of Voicebox — an open-source voice synthesis studio powered by Qwen3-TTS.
+
+### Voice Cloning with Qwen3-TTS
+
+- Automatic model download from HuggingFace
+- Multiple model sizes (1.7B and 0.6B)
+- Voice prompt caching for instant regeneration
+- English and Chinese support
+
+### Voice Profile Management
+
+- Create profiles from audio files or record directly in the app
+- Multiple samples per profile for higher quality cloning
+- Import/Export profiles
+- Automatic transcription via Whisper
+
+### Speech Generation
+
+- Simple text-to-speech with profile selection
+- Seed control for reproducible generations
+- Long-form support up to 5,000 characters
+
+### Generation History
+
+- Full history with metadata
+- Search by text content
+- Inline playback and download
+
+### Flexible Deployment
+
+- Local mode with bundled backend
+- Remote mode for GPU servers on your network
+- One-click server setup
+
+### Desktop Experience
+
+- Built with Tauri v2 (Rust) — native performance, not Electron
+- Cross-platform: macOS and Windows
+- No Python installation required
+
+### Tech Stack
+
+Tauri v2, React, TypeScript, Tailwind CSS, FastAPI, Qwen3-TTS, Whisper, SQLite
+
+[Unreleased]: https://github.com/jamiepine/voicebox/compare/v0.2.3...HEAD
+[0.2.3]: https://github.com/jamiepine/voicebox/compare/v0.2.2...v0.2.3
+[0.2.2]: https://github.com/jamiepine/voicebox/compare/v0.2.1...v0.2.2
+[0.2.1]: https://github.com/jamiepine/voicebox/compare/v0.1.13...v0.2.1
+[0.1.13]: https://github.com/jamiepine/voicebox/compare/v0.1.12...v0.1.13
+[0.1.12]: https://github.com/jamiepine/voicebox/compare/v0.1.11...v0.1.12
+[0.1.11]: https://github.com/jamiepine/voicebox/compare/v0.1.10...v0.1.11
+[0.1.10]: https://github.com/jamiepine/voicebox/compare/v0.1.9...v0.1.10
+[0.1.9]: https://github.com/jamiepine/voicebox/compare/v0.1.8...v0.1.9
+[0.1.8]: https://github.com/jamiepine/voicebox/compare/v0.1.7...v0.1.8
+[0.1.7]: https://github.com/jamiepine/voicebox/compare/v0.1.6...v0.1.7
+[0.1.6]: https://github.com/jamiepine/voicebox/compare/v0.1.5...v0.1.6
+[0.1.5]: https://github.com/jamiepine/voicebox/compare/v0.1.4...v0.1.5
+[0.1.4]: https://github.com/jamiepine/voicebox/compare/v0.1.3...v0.1.4
+[0.1.3]: https://github.com/jamiepine/voicebox/compare/v0.1.2...v0.1.3
+[0.1.2]: https://github.com/jamiepine/voicebox/compare/v0.1.1...v0.1.2
+[0.1.1]: https://github.com/jamiepine/voicebox/compare/v0.1.0...v0.1.1
 [0.1.0]: https://github.com/jamiepine/voicebox/releases/tag/v0.1.0

Dockerfile

@@ -31,6 +31,8 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     build-essential \
     && rm -rf /var/lib/apt/lists/*
 
+RUN pip install --no-cache-dir --upgrade pip
+
 COPY backend/requirements.txt .
 RUN pip install --no-cache-dir --prefix=/install -r requirements.txt
 RUN pip install --no-cache-dir --prefix=/install \

Makefile

@@ -1,250 +0,0 @@
-# Voicebox Makefile
-# Unix-only (macOS/Linux). Windows users should use WSL.
-
-SHELL := /bin/bash
-.DEFAULT_GOAL := help
-
-# Directories
-BACKEND_DIR := backend
-TAURI_DIR := tauri
-WEB_DIR := web
-APP_DIR := app
-
-# Python (prefer 3.12, fallback to 3.13, then python3)
-PYTHON := $(shell command -v python3.12 2>/dev/null || command -v python3.13 2>/dev/null || echo python3)
-VENV := $(CURDIR)/$(BACKEND_DIR)/venv
-VENV_BIN := $(VENV)/bin
-PIP := $(VENV_BIN)/pip
-PYTHON_VENV := $(VENV_BIN)/python
-
-# Colors for output
-BLUE := \033[0;34m
-GREEN := \033[0;32m
-YELLOW := \033[0;33m
-NC := \033[0m # No Color
-
-.PHONY: help
-help: ## Show this help message
-	@echo -e "$(BLUE)Voicebox$(NC) - Development Commands"
-	@echo ""
-	@grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | sort | \
-		awk 'BEGIN {FS = ":.*?## "}; {printf "  $(GREEN)%-20s$(NC) %s\n", $$1, $$2}'
-
-# =============================================================================
-# SETUP
-# =============================================================================
-
-.PHONY: setup setup-js setup-python setup-rust
-
-setup: setup-js setup-python ## Full project setup (all dependencies)
-	@echo -e "$(GREEN)✓ Setup complete!$(NC)"
-	@echo -e "  Run $(YELLOW)make dev$(NC) to start development servers"
-
-setup-js: ## Install JavaScript dependencies (bun)
-	@echo -e "$(BLUE)Installing JavaScript dependencies...$(NC)"
-	bun install
-
-setup-python: $(VENV)/bin/activate ## Set up Python virtual environment and dependencies
-	@echo -e "$(BLUE)Installing Python dependencies...$(NC)"
-	$(PIP) install --upgrade pip
-	$(PIP) install -r $(BACKEND_DIR)/requirements.txt
-	$(PIP) install --no-deps chatterbox-tts
-	@if [ "$$(uname -m)" = "arm64" ] && [ "$$(uname)" = "Darwin" ]; then \
-		echo -e "$(BLUE)Detected Apple Silicon - installing MLX dependencies...$(NC)"; \
-		$(PIP) install -r $(BACKEND_DIR)/requirements-mlx.txt; \
-		echo -e "$(GREEN)✓ MLX backend enabled (native Metal acceleration)$(NC)"; \
-	fi
-	$(PIP) install git+https://github.com/QwenLM/Qwen3-TTS.git
-	@echo -e "$(GREEN)✓ Python environment ready$(NC)"
-
-$(VENV)/bin/activate:
-	@echo -e "$(BLUE)Creating Python virtual environment...$(NC)"
-	@PY_MINOR=$$($(PYTHON) -c "import sys; print(sys.version_info[1])"); \
-	if [ "$$PY_MINOR" -gt 13 ]; then \
-		echo -e "$(YELLOW)Warning: Python 3.$$PY_MINOR detected. ML packages may not be compatible.$(NC)"; \
-		echo -e "$(YELLOW)Recommended: Use Python 3.12 or 3.13 (brew install [email protected])$(NC)"; \
-	fi
-	$(PYTHON) -m venv $(VENV)
-
-setup-rust: ## Install Rust toolchain (if not present)
-	@command -v rustc >/dev/null 2>&1 || curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
-
-# =============================================================================
-# DEVELOPMENT
-# =============================================================================
-
-.PHONY: dev dev-backend dev-frontend dev-web kill-dev
-
-dev: ## Start backend + desktop app (parallel)
-	@echo -e "$(BLUE)Starting development servers...$(NC)"
-	@echo -e "$(YELLOW)Note: If Tauri fails, run 'make build-server' first or use separate terminals$(NC)"
-	@trap 'kill 0' EXIT; \
-		$(MAKE) dev-backend & \
-		sleep 2 && if [ "$$(uname)" = "Linux" ] && lspci 2>/dev/null | grep -qi nvidia; then \
-			WEBKIT_DISABLE_DMABUF_RENDERER=1 $(MAKE) dev-frontend; \
-		else \
-			$(MAKE) dev-frontend; \
-		fi & \
-		wait
-
-dev-backend: ## Start FastAPI backend server
-	@echo -e "$(BLUE)Starting backend server on http://localhost:17493$(NC)"
-	$(VENV_BIN)/uvicorn backend.main:app --reload --port 17493
-
-dev-frontend: ## Start Tauri desktop app
-	@echo -e "$(BLUE)Starting Tauri desktop app...$(NC)"
-	bun run dev
-
-dev-web: ## Start backend + web app (parallel)
-	@echo -e "$(BLUE)Starting web development servers...$(NC)"
-	@trap 'kill 0' EXIT; \
-		$(MAKE) dev-backend & \
-		sleep 2 && cd $(WEB_DIR) && bun run dev & \
-		wait
-
-kill-dev: ## Kill all development processes
-	@echo -e "$(YELLOW)Killing development processes...$(NC)"
-	-pkill -f "uvicorn main:app" 2>/dev/null || true
-	-pkill -f "vite" 2>/dev/null || true
-	@echo -e "$(GREEN)✓ Processes killed$(NC)"
-
-# =============================================================================
-# BUILD
-# =============================================================================
-
-.PHONY: build build-server build-tauri build-web
-
-build: build-server build-tauri ## Build everything (server binary + desktop app)
-	@echo -e "$(GREEN)✓ Build complete!$(NC)"
-
-build-server: ## Build Python server binary
-	@echo -e "$(BLUE)Building server binary...$(NC)"
-	PATH="$(VENV_BIN):$$PATH" ./scripts/build-server.sh
-
-build-tauri: ## Build Tauri desktop app
-	@echo -e "$(BLUE)Building Tauri desktop app...$(NC)"
-	cd $(TAURI_DIR) && bun run tauri build
-
-build-web: ## Build web app
-	@echo -e "$(BLUE)Building web app...$(NC)"
-	cd $(WEB_DIR) && bun run build
-	@echo -e "$(GREEN)✓ Web build output in $(WEB_DIR)/dist/$(NC)"
-
-# =============================================================================
-# DATABASE & API
-# =============================================================================
-
-.PHONY: db-init db-reset generate-api
-
-db-init: $(VENV)/bin/activate ## Initialize SQLite database
-	@echo -e "$(BLUE)Initializing database...$(NC)"
-	cd $(BACKEND_DIR) && $(PYTHON_VENV) -c "from database import init_db; init_db()"
-	@echo -e "$(GREEN)✓ Database created at $(BACKEND_DIR)/data/voicebox.db$(NC)"
-
-db-reset: ## Reset database (delete and reinitialize)
-	@echo -e "$(YELLOW)Resetting database...$(NC)"
-	rm -f $(BACKEND_DIR)/data/voicebox.db
-	$(MAKE) db-init
-
-generate-api: ## Generate TypeScript API client from OpenAPI schema
-	@echo -e "$(BLUE)Generating API client...$(NC)"
-	@echo -e "$(YELLOW)Note: Backend must be running (make dev-backend)$(NC)"
-	./scripts/generate-api.sh
-	@echo -e "$(GREEN)✓ API client generated in $(APP_DIR)/src/lib/api/$(NC)"
-
-# =============================================================================
-# CODE QUALITY
-# =============================================================================
-
-.PHONY: lint format typecheck check
-
-lint: ## Run linter (Biome)
-	@echo -e "$(BLUE)Linting...$(NC)"
-	bun run lint
-
-format: ## Format code (Biome)
-	@echo -e "$(BLUE)Formatting...$(NC)"
-	bun run format
-
-typecheck: ## Run TypeScript type checking
-	@echo -e "$(BLUE)Type checking...$(NC)"
-	bun run tsc --noEmit
-
-check: ## Run all checks (Biome lint + format + type check)
-	@echo -e "$(BLUE)Running all checks...$(NC)"
-	bun run check
-	@echo -e "$(GREEN)✓ All checks passed$(NC)"
-
-# =============================================================================
-# TESTING
-# =============================================================================
-
-.PHONY: test test-backend test-frontend
-
-test: test-backend test-frontend ## Run all tests
-	@echo -e "$(GREEN)✓ All tests passed$(NC)"
-
-test-backend: ## Run Python backend tests (requires pytest)
-	@echo -e "$(BLUE)Running backend tests...$(NC)"
-	@if [ -f "$(VENV_BIN)/pytest" ]; then \
-		cd $(BACKEND_DIR) && $(VENV_BIN)/pytest -v; \
-	else \
-		echo -e "$(YELLOW)pytest not installed. Run: $(PIP) install pytest$(NC)"; \
-		exit 1; \
-	fi
-
-test-frontend: ## Run frontend tests (requires test script in package.json)
-	@echo -e "$(BLUE)Running frontend tests...$(NC)"
-	@if bun run test --help >/dev/null 2>&1; then \
-		bun run test; \
-	else \
-		echo -e "$(YELLOW)No test script configured$(NC)"; \
-		exit 1; \
-	fi
-
-# =============================================================================
-# LOGS & DEBUGGING
-# =============================================================================
-
-.PHONY: logs docs
-
-logs: ## Tail backend logs
-	@echo -e "$(BLUE)Tailing logs (Ctrl+C to stop)...$(NC)"
-	tail -f $(BACKEND_DIR)/logs/*.log 2>/dev/null || echo "No log files found"
-
-docs: ## Open API documentation (backend must be running)
-	@echo -e "$(BLUE)Opening API docs...$(NC)"
-	open http://localhost:17493/docs 2>/dev/null || xdg-open http://localhost:17493/docs
-
-# =============================================================================
-# CLEAN
-# =============================================================================
-
-.PHONY: clean clean-python clean-build clean-all
-
-clean: ## Clean build artifacts
-	@echo -e "$(BLUE)Cleaning build artifacts...$(NC)"
-	rm -rf $(TAURI_DIR)/src-tauri/target/release
-	rm -rf $(WEB_DIR)/dist
-	rm -rf $(APP_DIR)/dist
-	@echo -e "$(GREEN)✓ Build artifacts cleaned$(NC)"
-
-clean-python: ## Clean Python cache and virtual environment
-	@echo -e "$(BLUE)Cleaning Python files...$(NC)"
-	rm -rf $(VENV)
-	find $(BACKEND_DIR) -type d -name "__pycache__" -exec rm -rf {} + 2>/dev/null || true
-	find $(BACKEND_DIR) -type f -name "*.pyc" -delete 2>/dev/null || true
-	@echo -e "$(GREEN)✓ Python environment cleaned$(NC)"
-
-clean-build: ## Clean Rust/Tauri build cache
-	@echo -e "$(BLUE)Cleaning Rust build cache...$(NC)"
-	cd $(TAURI_DIR)/src-tauri && cargo clean
-	@echo -e "$(GREEN)✓ Rust cache cleaned$(NC)"
-
-clean-all: clean clean-python clean-build ## Nuclear clean (everything)
-	@echo -e "$(BLUE)Cleaning node_modules...$(NC)"
-	rm -rf node_modules
-	rm -rf $(APP_DIR)/node_modules
-	rm -rf $(TAURI_DIR)/node_modules
-	rm -rf $(WEB_DIR)/node_modules
-	@echo -e "$(GREEN)✓ Full clean complete$(NC)"

PATCH_NOTES.md

@@ -1,58 +0,0 @@
-# Voicebox Offline Mode Fix
-
-## Problem
-Voicebox crashes when generating speech if HuggingFace is unreachable, even when models are fully cached locally.
-
-**Root Cause:**
-- Voicebox downloads `mlx-community/Qwen3-TTS-12Hz-1.7B-Base-bf16` (MLX optimized version)
-- But `mlx_audio.tts.load()` tries to fetch `config.json` from original repo `Qwen/Qwen3-TTS-12Hz-1.7B-Base`
-- This network request fails → server crashes with `RemoteDisconnected`
-
-**Related Issues:**
-- Issue #150: "Internet connection required, even though models are downloaded?"
-- Issue #151: "API Stability Issues: Model Loading Hangs and Server Crashes"
-
-## Solution
-Two-part fix:
-
-### 1. Monkey-patch huggingface_hub (`backend/utils/hf_offline_patch.py`)
-- Intercepts cache lookup functions
-- Forces offline mode early (before mlx_audio imports)
-- Adds debug logging for cache hits/misses
-
-### 2. Symlink original repo to MLX version (`ensure_original_qwen_config_cached()`)
-- When original `Qwen/Qwen3-TTS-12Hz-1.7B-Base` cache doesn't exist
-- But MLX `mlx-community/Qwen3-TTS-12Hz-1.7B-Base-bf16` does exist
-- Creates a symlink so cache lookups succeed
-
-## Files Changed
-- `backend/backends/mlx_backend.py` - Added patch imports at top
-- `backend/utils/hf_offline_patch.py` - New patch module
-
-## Testing
-To test this fix:
-1. Build Voicebox from source: `make build`
-2. Disconnect from internet
-3. Try generating speech
-4. Should work without network requests
-
-## Build Instructions
-
-```bash
-# Install dependencies
-pip install -r requirements.txt
-
-# Build the app
-make build
-
-# Or build just the server
-make build-server
-```
-
-## Notes
-- The patch is applied automatically when `mlx_backend.py` is imported
-- Set `VOICEBOX_OFFLINE_PATCH=0` to disable the patch
-- The symlink approach works because the config.json is compatible between versions
-
----
-*Patch contributed by community*

README.md

@@ -6,7 +6,7 @@
 
 <p align="center">
   <strong>The open-source voice synthesis studio.</strong><br/>
-  Clone voices. Generate speech. Build voice-powered apps.<br/>
+  Clone voices. Generate speech. Apply effects. Build voice-powered apps.<br/>
   All running locally on your machine.
 </p>
 
@@ -27,10 +27,10 @@
 
 <p align="center">
   <a href="https://voicebox.sh">voicebox.sh</a> •
+  <a href="https://docs.voicebox.sh">Docs</a> •
   <a href="#download">Download</a> •
   <a href="#features">Features</a> •
-  <a href="#api">API</a> •
+  <a href="#api">API</a>
-  <a href="#roadmap">Roadmap</a>
 </p>
 
 <br/>
@@ -59,96 +59,147 @@
 
 ## What is Voicebox?
 
-Voicebox is a **local-first voice cloning studio** with DAW-like features for professional voice synthesis. Think of it as a **local, free and open-source alternative to ElevenLabs** — download models, clone voices, and generate speech entirely on your machine.
+Voicebox is a **local-first voice cloning studio** — a free and open-source alternative to ElevenLabs. Clone voices from a few seconds of audio, generate speech in 23 languages across 4 TTS engines, apply post-processing effects, and compose multi-voice projects with a timeline editor.
-
-Unlike cloud services that lock your voice data behind subscriptions, Voicebox gives you:
 
 - **Complete privacy** — models and voice data stay on your machine
-- **Professional tools** — multi-track timeline editor, audio trimming, conversation mixing
+- **4 TTS engines** — Qwen3-TTS, LuxTTS, Chatterbox Multilingual, and Chatterbox Turbo
-- **Model flexibility** — currently powered by Qwen3-TTS, with support for XTTS, Bark, and other models coming soon
+- **23 languages** — from English to Arabic, Japanese, Hindi, Swahili, and more
-- **API-first** — use the desktop app or integrate voice synthesis into your own projects
+- **Post-processing effects** — pitch shift, reverb, delay, chorus, compression, and filters
+- **Expressive speech** — paralinguistic tags like `[laugh]`, `[sigh]`, `[gasp]` via Chatterbox Turbo
+- **Unlimited length** — auto-chunking with crossfade for scripts, articles, and chapters
+- **Stories editor** — multi-track timeline for conversations, podcasts, and narratives
+- **API-first** — REST API for integrating voice synthesis into your own projects
 - **Native performance** — built with Tauri (Rust), not Electron
-- **Super fast on Mac** — MLX backend with native Metal acceleration for 4-5x faster inference on Apple Silicon
+- **Runs everywhere** — macOS (MLX/Metal), Windows (CUDA), Linux, AMD ROCm, Intel Arc, Docker
-
-Download a voice model, clone any voice from a few seconds of audio, and compose multi-voice projects with studio-grade editing tools. No Python install required, no cloud dependency, no limits.
 
 ---
 
 ## Download
 
-Voicebox is available now for macOS and Windows.
+| Platform              | Download                                               |
+| --------------------- | ------------------------------------------------------ |
+| macOS (Apple Silicon) | [Download DMG](https://voicebox.sh/download/mac-arm)   |
+| macOS (Intel)         | [Download DMG](https://voicebox.sh/download/mac-intel) |
+| Windows               | [Download MSI](https://voicebox.sh/download/windows)   |
+| Docker                | `docker compose up`                                    |
 
-| Platform | Download |
+> **[View all binaries →](https://github.com/jamiepine/voicebox/releases/latest)**
-|----------|----------|
-| macOS (Apple Silicon) | [Voicebox_aarch64.app.tar.gz](https://github.com/jamiepine/voicebox/releases/latest/download/Voicebox_aarch64.app.tar.gz) |
-| macOS (Intel) | [Voicebox_x64.app.tar.gz](https://github.com/jamiepine/voicebox/releases/latest/download/Voicebox_x64.app.tar.gz) |
-| Windows (MSI) | [Latest Windows MSI](https://github.com/jamiepine/voicebox/releases/latest) |
-| Windows (Setup) | [Latest Windows Setup](https://github.com/jamiepine/voicebox/releases/latest) |
 
-> **Linux** — Pre-built binaries are not yet available. Linux users can compile from source, see [Development](#development) below.
+> **Linux** — Pre-built binaries are not yet available. See [voicebox.sh/linux-install](https://voicebox.sh/linux-install) for build-from-source instructions.
 
 ---
 
 ## Features
 
-### Voice Cloning with Qwen3-TTS
+### Multi-Engine Voice Cloning
 
-Powered by Alibaba's **Qwen3-TTS** — a breakthrough model that achieves near-perfect voice cloning from just a few seconds of audio.
+Four TTS engines with different strengths, switchable per-generation:
 
-- **Instant cloning** — Upload a sample, get a voice profile
+| Engine                      | Languages | Strengths                                                                                                                                |
-- **High fidelity** — Natural prosody, emotion, and cadence
+| --------------------------- | --------- | ---------------------------------------------------------------------------------------------------------------------------------------- |
-- **Multi-language** — English, Chinese, and more coming
+| **Qwen3-TTS** (0.6B / 1.7B) | 10        | High-quality multilingual cloning, delivery instructions ("speak slowly", "whisper")                                                     |
-- **Lightning fast on Mac** — MLX backend leverages Apple Silicon's Neural Engine for super-fast generation
+| **LuxTTS**                  | English   | Lightweight (~1GB VRAM), 48kHz output, 150x realtime on CPU                                                                              |
+| **Chatterbox Multilingual** | 23        | Broadest language coverage — Arabic, Danish, Finnish, Greek, Hebrew, Hindi, Malay, Norwegian, Polish, Swahili, Swedish, Turkish and more |
+| **Chatterbox Turbo**        | English   | Fast 350M model with paralinguistic emotion/sound tags                                                                                   |
+
+### Emotions & Paralinguistic Tags
+
+Type `/` in the text input to insert expressive tags that the model synthesizes inline with speech (Chatterbox Turbo):
+
+`[laugh]` `[chuckle]` `[gasp]` `[cough]` `[sigh]` `[groan]` `[sniff]` `[shush]` `[clear throat]`
+
+### Post-Processing Effects
+
+8 audio effects powered by Spotify's `pedalboard` library. Apply after generation, preview in real time, build reusable presets.
+
+| Effect           | Description                                   |
+| ---------------- | --------------------------------------------- |
+| Pitch Shift      | Up or down by up to 12 semitones              |
+| Reverb           | Configurable room size, damping, wet/dry mix  |
+| Delay            | Echo with adjustable time, feedback, and mix  |
+| Chorus / Flanger | Modulated delay for metallic or lush textures |
+| Compressor       | Dynamic range compression                     |
+| Gain             | Volume adjustment (-40 to +40 dB)             |
+| High-Pass Filter | Remove low frequencies                        |
+| Low-Pass Filter  | Remove high frequencies                       |
+
+Ships with 4 built-in presets (Robotic, Radio, Echo Chamber, Deep Voice) and supports custom presets. Effects can be assigned per-profile as defaults.
+
+### Unlimited Generation Length
+
+Text is automatically split at sentence boundaries and each chunk is generated independently, then crossfaded together. Works with all engines.
+
+- Configurable auto-chunking limit (100–5,000 chars)
+- Crossfade slider (0–200ms) for smooth transitions
+- Max text length: 50,000 characters
+- Smart splitting respects abbreviations, CJK punctuation, and `[tags]`
+
+### Generation Versions
+
+Every generation supports multiple versions with provenance tracking:
+
+- **Original** — clean TTS output, always preserved
+- **Effects versions** — apply different effects chains from any source version
+- **Takes** — regenerate with a new seed for variation
+- **Source tracking** — each version records its lineage
+- **Favorites** — star generations for quick access
+
+### Async Generation Queue
+
+Generation is non-blocking. Submit and immediately start typing the next one.
+
+- Serial execution queue prevents GPU contention
+- Real-time SSE status streaming
+- Failed generations can be retried
+- Stale generations from crashes auto-recover on startup
 
 ### Voice Profile Management
 
-- **Create profiles** from audio files or record directly in-app
+- Create profiles from audio files or record directly in-app
-- **Import/Export** profiles to share or back up
+- Import/export profiles to share or back up
-- **Multi-sample support** — combine multiple samples for higher quality cloning
+- Multi-sample support for higher quality cloning
-- **Organize** with descriptions and language tags
+- Per-profile default effects chains
-
+- Organize with descriptions and language tags
-### Speech Generation
-
-- **Text-to-speech** with any cloned voice
-- **Batch generation** for long-form content
-- **Smart caching** — regenerate instantly with voice prompt caching
 
 ### Stories Editor
 
-Create multi-voice narratives, podcasts, and conversations with a timeline-based editor.
+Multi-voice timeline editor for conversations, podcasts, and narratives.
 
-- **Multi-track composition** — arrange multiple voice tracks in a single project
+- Multi-track composition with drag-and-drop
-- **Inline audio editing** — trim and split clips directly in the timeline
+- Inline audio trimming and splitting
-- **Auto-playback** — preview stories with synchronized playhead
+- Auto-playback with synchronized playhead
-- **Voice mixing** — build conversations with multiple participants
+- Version pinning per track clip
 
 ### Recording & Transcription
 
-- **In-app recording** with waveform visualization
+- In-app recording with waveform visualization
-- **System audio capture** — record desktop audio on macOS and Windows
+- System audio capture (macOS and Windows)
-- **Automatic transcription** powered by Whisper
+- Automatic transcription powered by Whisper (including Whisper Turbo)
-- **Export recordings** in multiple formats
+- Export recordings in multiple formats
 
-### Generation History
+### Model Management
 
-- **Full history** of all generated audio
+- Per-model unload to free GPU memory without deleting downloads
-- **Search & filter** by voice, text, or date
+- Custom models directory via `VOICEBOX_MODELS_DIR`
-- **Re-generate** any past generation with one click
+- Model folder migration with progress tracking
+- Download cancel/clear UI
 
-### Flexible Deployment
+### GPU Support
 
-- **Local mode** — Everything runs on your machine
+| Platform                 | Backend        | Notes                                          |
-- **Remote mode** — Connect to a GPU server on your network
+| ------------------------ | -------------- | ---------------------------------------------- |
-- **One-click server** — Turn any machine into a Voicebox server
+| macOS (Apple Silicon)    | MLX (Metal)    | 4-5x faster via Neural Engine                  |
+| Windows / Linux (NVIDIA) | PyTorch (CUDA) | Auto-downloads CUDA binary from within the app |
+| Linux (AMD)              | PyTorch (ROCm) | Auto-configures HSA_OVERRIDE_GFX_VERSION       |
+| Windows (any GPU)        | DirectML       | Universal Windows GPU support                  |
+| Intel Arc                | IPEX/XPU       | Intel discrete GPU acceleration                |
+| Any                      | CPU            | Works everywhere, just slower                  |
 
 ---
 
 ## API
 
-Voicebox exposes a full REST API, so you can integrate voice synthesis into your own apps.
+Voicebox exposes a full REST API for integrating voice synthesis into your own apps.
-
-For the current local app and development workflow, the backend is typically available at `http://localhost:17493`.
-If you launch the backend manually with a different host or port, use that address instead.
 
 ```bash
 # Generate speech
@@ -165,62 +216,38 @@ curl -X POST http://localhost:17493/profiles \
   -d '{"name": "My Voice", "language": "en"}'
 ```
 
-**Use cases:**
+**Use cases:** game dialogue, podcast production, accessibility tools, voice assistants, content automation.
 
-- Game dialogue systems
+Full API documentation available at `http://localhost:17493/docs`.
-- Podcast/video production pipelines
-- Accessibility tools
-- Voice assistants
-- Content creation automation
-
-Full API documentation is available at `http://localhost:17493/docs` in the default local workflow, or at `/docs` on whatever server address you configured.
 
 ---
 
 ## Tech Stack
 
-| Layer | Technology |
+| Layer         | Technology                                        |
-|-------|------------|
+| ------------- | ------------------------------------------------- |
-| Desktop App | Tauri (Rust) |
+| Desktop App   | Tauri (Rust)                                      |
-| Frontend | React, TypeScript, Tailwind CSS |
+| Frontend      | React, TypeScript, Tailwind CSS                   |
-| State | Zustand, React Query |
+| State         | Zustand, React Query                              |
-| Backend | FastAPI (Python) |
+| Backend       | FastAPI (Python)                                  |
-| Voice Model | Qwen3-TTS (PyTorch or MLX) |
+| TTS Engines   | Qwen3-TTS, LuxTTS, Chatterbox, Chatterbox Turbo   |
-| Transcription | Whisper (PyTorch or MLX) |
+| Effects       | Pedalboard (Spotify)                              |
-| Inference Engine | MLX (Apple Silicon) / PyTorch (Windows/Linux/Intel) |
+| Transcription | Whisper / Whisper Turbo (PyTorch or MLX)          |
-| Database | SQLite |
+| Inference     | MLX (Apple Silicon) / PyTorch (CUDA/ROCm/XPU/CPU) |
-| Audio | WaveSurfer.js, librosa |
+| Database      | SQLite                                            |
-
+| Audio         | WaveSurfer.js, librosa                            |
-**Why this stack?**
-
-- **Tauri over Electron** — 10x smaller bundle, native performance, lower memory
-- **FastAPI** — Async Python with automatic OpenAPI schema generation
-- **Type-safe end-to-end** — Generated TypeScript client from OpenAPI spec
 
 ---
 
 ## Roadmap
 
-Voicebox is the beginning of something bigger. Here's what's coming:
+| Feature                 | Description                                    |
-
+| ----------------------- | ---------------------------------------------- |
-### Coming Soon
+| **Real-time Streaming** | Stream audio as it generates, word by word     |
-
+| **Voice Design**        | Create new voices from text descriptions       |
-| Feature | Description |
+| **More Models**         | XTTS, Bark, and other open-source voice models |
-|---------|-------------|
+| **Plugin Architecture** | Extend with custom models and effects          |
-| **Real-time Synthesis** | Stream audio as it generates, word by word |
+| **Mobile Companion**    | Control Voicebox from your phone               |
-| **Conversation Mode** | Multi-speaker dialogues with automatic turn-taking |
-| **Voice Effects** | Pitch shift, reverb, M3GAN-style effects |
-| **Timeline Editor** | Audio studio with word-level precision editing |
-| **More Models** | XTTS, Bark, and other open-source voice models |
-
-### Future Vision
-
-- **Voice Design** — Create new voices from text descriptions
-- **Project System** — Save and load complex multi-voice sessions
-- **Plugin Architecture** — Extend with custom models and effects
-- **Mobile Companion** — Control Voicebox from your phone
-
-Voicebox aims to be the **one-stop shop for everything voice** — cloning, synthesis, editing, effects, and beyond.
 
 ---
 
@@ -242,14 +269,6 @@ Install [just](https://github.com/casey/just): `brew install just` or `cargo ins
 
 **Prerequisites:** [Bun](https://bun.sh), [Rust](https://rustup.rs), [Python 3.11+](https://python.org), [Tauri Prerequisites](https://v2.tauri.app/start/prerequisites/), and [Xcode](https://developer.apple.com/xcode/) on macOS.
 
-### Platform Notes
-
-| Platform | GPU Backend | Notes |
-|----------|-------------|-------|
-| macOS (Apple Silicon) | MLX (Metal) | 4-5x faster inference via Neural Engine |
-| Windows (NVIDIA) | PyTorch (CUDA) | `just setup` auto-installs CUDA PyTorch |
-| Windows/Linux (no NVIDIA) | PyTorch (CPU) | Works but slower |
-
 ### Building Locally
 
 ```bash
@@ -257,8 +276,6 @@ just build          # Build CPU server binary + Tauri app
 just build-local    # (Windows) Build CPU + CUDA server binaries + Tauri app
 ```
 
-`just build-local` produces a production-ready installer with the CUDA binary pre-placed for GPU switching.
-
 ### Project Structure
 
 ```

app/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@voicebox/app",
-  "version": "0.2.4",
+  "version": "0.2.3",
   "private": true,
   "type": "module",
   "scripts": {

app/plugins/changelog.ts

@@ -0,0 +1,23 @@
+import { readFileSync } from 'node:fs';
+import path from 'node:path';
+import type { Plugin } from 'vite';
+
+/** Vite plugin that exposes CHANGELOG.md as `virtual:changelog`. */
+export function changelogPlugin(repoRoot: string): Plugin {
+  const virtualId = 'virtual:changelog';
+  const resolvedId = '\0' + virtualId;
+  const changelogPath = path.resolve(repoRoot, 'CHANGELOG.md');
+
+  return {
+    name: 'changelog',
+    resolveId(id) {
+      if (id === virtualId) return resolvedId;
+    },
+    load(id) {
+      if (id === resolvedId) {
+        const raw = readFileSync(changelogPath, 'utf-8');
+        return `export default ${JSON.stringify(raw)};`;
+      }
+    },
+  };
+}

app/src/App.tsx

@@ -8,6 +8,7 @@ import { TOP_SAFE_AREA_PADDING } from '@/lib/constants/ui';
 import { cn } from '@/lib/utils/cn';
 import { usePlatform } from '@/platform/PlatformContext';
 import { router } from '@/router';
+import { useLogStore } from '@/stores/logStore';
 import { useServerStore } from '@/stores/serverStore';
 
 const LOADING_MESSAGES = [
@@ -63,6 +64,14 @@ function App() {
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [platform.lifecycle]);
 
+  // Subscribe to server logs
+  useEffect(() => {
+    const unsubscribe = platform.lifecycle.subscribeToServerLogs((entry) => {
+      useLogStore.getState().addEntry(entry);
+    });
+    return unsubscribe;
+  }, [platform.lifecycle]);
+
   // Setup window close handler and auto-start server when running in Tauri (production only)
   useEffect(() => {
     if (!platform.metadata.isTauri) {

app/src/components/AudioPlayer/AudioPlayer.tsx

@@ -17,7 +17,6 @@ export function AudioPlayer() {
     audioUrl,
     audioId,
     profileId,
-    title,
     isPlaying,
     currentTime,
     duration,
@@ -63,7 +62,7 @@ export function AudioPlayer() {
     );
 
     return shouldUseNative;
-  }, [profileChannels, channels, profileId]);
+  }, [profileChannels, channels, platform.metadata.isTauri]);
 
   const waveformRef = useRef<HTMLDivElement>(null);
   const wavesurferRef = useRef<WaveSurfer | null>(null);
@@ -73,31 +72,21 @@ export function AudioPlayer() {
   const isUsingNativePlaybackRef = useRef(false);
   const [isLoading, setIsLoading] = useState(false);
   const [error, setError] = useState<string | null>(null);
+  const [wsReady, setWsReady] = useState(false);
 
-  // Initialize WaveSurfer (only when audioUrl exists and container is ready)
+  // Create WaveSurfer once when the player becomes visible (audioUrl is set).
+  // This instance is reused for all subsequent audio loads - never destroyed until unmount.
   useEffect(() => {
-    // Don't initialize if no audioUrl or already initialized
+    if (!audioUrl) return;
-    if (!audioUrl) {
+    if (wavesurferRef.current) return; // already created
-      return;
-    }
 
-    if (wavesurferRef.current) {
-      debug.log('WaveSurfer already initialized, skipping');
-      return;
-    }
-
-    debug.log('Creating NEW WaveSurfer instance');
-
-    // Wait for container to be properly rendered
     const initWaveSurfer = () => {
       const container = waveformRef.current;
       if (!container) {
-        // Container not ready yet, retry
         setTimeout(initWaveSurfer, 50);
         return;
       }
 
-      // Check if container has dimensions and is visible
       const rect = container.getBoundingClientRect();
       const style = window.getComputedStyle(container);
       const isVisible =
@@ -107,412 +96,221 @@ export function AudioPlayer() {
         style.visibility !== 'hidden';
 
       if (!isVisible) {
-        // Retry after a short delay
         setTimeout(initWaveSurfer, 50);
         return;
       }
 
-      debug.log('Initializing WaveSurfer...', {
+      debug.log('Creating WaveSurfer instance', {
-        container,
         width: rect.width,
         height: rect.height,
       });
 
       try {
-        // Get computed CSS variable values
         const root = document.documentElement;
         const getCSSVar = (varName: string) => {
           const value = getComputedStyle(root).getPropertyValue(varName).trim();
           return value ? `hsl(${value})` : '';
         };
 
-        const waveColor = getCSSVar('--muted');
-        const progressColor = getCSSVar('--accent');
-        const cursorColor = getCSSVar('--accent');
-
         const wavesurfer = WaveSurfer.create({
-          container: container,
+          container,
-          waveColor: waveColor,
+          waveColor: getCSSVar('--muted'),
-          progressColor: progressColor,
+          progressColor: getCSSVar('--accent'),
-          cursorColor: cursorColor,
+          cursorColor: getCSSVar('--accent'),
+          cursorWidth: 3,
           barWidth: 2,
           barRadius: 2,
           height: 80,
           normalize: true,
-          // Use MediaElement backend (default). Unlike the WebAudio backend,
+          interact: true,
-          // MediaElement uses a standard <audio> element for playback which
+          dragToSeek: { debounceTime: 0 },
-          // benefits from the browser/webview's built-in audio session recovery.
+          mediaControls: false,
-          // This prevents audio loss when another app steals audio output or
+          backend: 'WebAudio',
-          // the system audio session is interrupted.
-          interact: true, // Enable interaction (click to seek)
-          mediaControls: false, // Don't show native controls
         });
 
-        wavesurferRef.current = wavesurfer;
+        // Wire up event handlers (these persist for the lifetime of the instance)
-        debug.log('WaveSurfer created successfully');
+        wavesurfer.on('timeupdate', (time) => {
-      } catch (error) {
+          const dur = usePlayerStore.getState().duration;
-        debug.error('Failed to create WaveSurfer:', error);
+          if (dur > 0 && time >= dur) {
-        setError(
+            setCurrentTime(dur);
-          `Failed to initialize waveform: ${error instanceof Error ? error.message : String(error)}`,
+            const loop = usePlayerStore.getState().isLooping;
-        );
+            if (loop) {
-        return;
+              wavesurfer.seekTo(0);
-      }
+              wavesurfer.play().catch((err) => debug.error('Loop play failed:', err));
+            } else {
+              wavesurfer.pause();
+              setIsPlaying(false);
+            }
+            return;
+          }
+          setCurrentTime(time);
+        });
 
-      const wavesurfer = wavesurferRef.current;
+        wavesurfer.on('ready', () => {
-      if (!wavesurfer) return;
+          const dur = wavesurfer.getDuration();
+          setDuration(dur);
+          loadingRef.current = false;
+          setIsLoading(false);
+          setError(null);
+          debug.log('Audio ready, duration:', dur);
 
-      // Update store when time changes, stop if past duration
+          wavesurfer.setVolume(usePlayerStore.getState().volume);
-      wavesurfer.on('timeupdate', (time) => {
+          wavesurfer.setMuted(false);
-        const dur = usePlayerStore.getState().duration;
+
-        if (dur > 0 && time >= dur) {
+          // Auto-play if the flag is set (story mode advance or explicit play)
-          setCurrentTime(dur);
+          const shouldAutoPlayNow = usePlayerStore.getState().shouldAutoPlay;
+          if (shouldAutoPlayNow) {
+            usePlayerStore.getState().clearAutoPlayFlag();
+            wavesurfer.play().catch((err) => {
+              debug.error('Failed to autoplay:', err);
+            });
+          } else {
+            debug.log('Skipping auto-play - shouldAutoPlay is false');
+          }
+        });
+
+        wavesurfer.on('play', () => setIsPlaying(true));
+        wavesurfer.on('pause', () => {
+          setIsPlaying(false);
+          setCurrentTime(wavesurfer.getCurrentTime());
+        });
+
+        wavesurfer.on('seeking', (time) => setCurrentTime(time));
+
+        // Mute audio during drag-to-seek to prevent popping from the WebAudio
+        // backend's hard stop/start cycle on each seek. Unmute with a short
+        // fade-in when the drag ends.
+        const seekMedia = wavesurfer.getMediaElement() as any;
+        const seekGain: GainNode | null = seekMedia?.getGainNode?.() ?? null;
+        if (seekGain) {
+          const ctx = seekGain.context as AudioContext;
+          wavesurfer.on('dragstart', () => {
+            seekGain.gain.cancelScheduledValues(ctx.currentTime);
+            seekGain.gain.setTargetAtTime(0, ctx.currentTime, 0.002);
+          });
+          wavesurfer.on('dragend', () => {
+            seekGain.gain.cancelScheduledValues(ctx.currentTime);
+            seekGain.gain.setTargetAtTime(1, ctx.currentTime, 0.01);
+          });
+        }
+        wavesurfer.on('finish', () => {
           const loop = usePlayerStore.getState().isLooping;
           if (loop) {
             wavesurfer.seekTo(0);
-            wavesurfer.play();
+            wavesurfer.play().catch((err) => debug.error('Loop play failed:', err));
           } else {
-            wavesurfer.pause();
             setIsPlaying(false);
+            const onFinish = usePlayerStore.getState().onFinish;
+            if (onFinish) onFinish();
           }
-          return;
-        }
-        setCurrentTime(time);
-      });
-
-      // Update store when duration is loaded
-      wavesurfer.on('ready', async () => {
-        const dur = wavesurfer.getDuration();
-        setDuration(dur);
-        loadingRef.current = false;
-        setIsLoading(false);
-        setError(null);
-        debug.log('Audio ready, duration:', dur);
-        debug.log('Waveform should be visible now');
-
-        // Ensure volume is set
-        const currentVolume = usePlayerStore.getState().volume;
-        wavesurfer.setVolume(currentVolume);
-
-        // Auto-play when ready - check if we should use native playback
-        // Get current values from the store and queries at runtime (not captured closure values)
-        const currentAudioUrl = usePlayerStore.getState().audioUrl;
-        const currentProfileId = usePlayerStore.getState().profileId;
-
-        debug.log('Auto-play check - capturing runtime values...');
-
-        // Fetch profile channels at runtime (not using captured value)
-        let runtimeProfileChannels = null;
-        let runtimeChannels = null;
-
-        if (platform.metadata.isTauri && currentProfileId) {
-          try {
-            runtimeProfileChannels = await apiClient.getProfileChannels(currentProfileId);
-            debug.log('Runtime profileChannels:', runtimeProfileChannels);
-
-            if (runtimeProfileChannels && runtimeProfileChannels.channel_ids.length > 0) {
-              runtimeChannels = await apiClient.listChannels();
-              debug.log('Runtime channels:', runtimeChannels);
-            }
-          } catch (error) {
-            debug.error('Failed to fetch runtime channel data:', error);
-          }
-        }
-
-        debug.log('Auto-play check:', {
-          isTauri: platform.metadata.isTauri,
-          currentAudioUrl,
-          currentProfileId,
-          hasProfileChannels: !!runtimeProfileChannels,
-          hasChannels: !!runtimeChannels,
         });
 
-        if (
+        wavesurfer.on('error', (err) => {
-          platform.metadata.isTauri &&
+          debug.error('WaveSurfer error:', err);
-          currentAudioUrl &&
-          currentProfileId &&
-          runtimeProfileChannels &&
-          runtimeChannels
-        ) {
-          debug.log('Attempting native audio playback...');
-
-          // Stop any existing native playback first
-          if (isUsingNativePlaybackRef.current) {
-            try {
-              platform.audio.stopPlayback();
-              debug.log('Stopped existing native playback before starting new one');
-            } catch (error) {
-              debug.error('Failed to stop existing playback:', error);
-            }
-          }
-
-          try {
-            // Collect all device IDs from assigned channels
-            const assignedChannels = runtimeChannels.filter((ch: any) =>
-              runtimeProfileChannels.channel_ids.includes(ch.id),
-            );
-            debug.log('Assigned channels for playback:', assignedChannels);
-
-            // Check if any assigned channel has non-default devices
-            const shouldUseNative = assignedChannels.some(
-              (ch: any) => ch.device_ids.length > 0 && !ch.is_default,
-            );
-            debug.log('Should use native playback:', shouldUseNative);
-
-            if (!shouldUseNative) {
-              debug.log('No custom devices assigned, using standard playback');
-              isUsingNativePlaybackRef.current = false;
-            } else {
-              const deviceIds = assignedChannels.flatMap((ch: any) => ch.device_ids);
-              debug.log('Device IDs to play to:', deviceIds);
-
-              if (deviceIds.length > 0) {
-                debug.log('Fetching audio data from:', currentAudioUrl);
-                // Fetch audio data
-                const response = await fetch(currentAudioUrl);
-                const audioData = new Uint8Array(await response.arrayBuffer());
-                debug.log('Audio data size:', audioData.length);
-
-                // Play via native audio
-                debug.log('Invoking play_audio_to_devices...');
-                try {
-                  await platform.audio.playToDevices(audioData, deviceIds);
-                  debug.log('play_audio_to_devices completed successfully');
-
-                  // Mark that we're using native playback
-                  isUsingNativePlaybackRef.current = true;
-
-                  // Mute WaveSurfer's audio output — native handles the actual sound
-                  // Keep WaveSurfer running for waveform visualization
-                  wavesurfer.setVolume(0);
-                  wavesurfer.setMuted(true);
-
-                  // Start WaveSurfer playback for visualization (muted)
-                  wavesurfer.play().catch((error) => {
-                    debug.error('Failed to start WaveSurfer visualization:', error);
-                  });
-
-                  setIsPlaying(true);
-                  debug.log('Auto-playing via native audio routing - SUCCESS');
-                  return;
-                } catch (invokeError) {
-                  debug.error('play_audio_to_devices invoke failed:', invokeError);
-                  throw invokeError;
-                }
-              } else {
-                debug.log('No device IDs found, falling back to WaveSurfer');
-              }
-            }
-          } catch (error) {
-            debug.error(
-              'Native playback failed during auto-play, falling back to WaveSurfer:',
-              error,
-            );
-            isUsingNativePlaybackRef.current = false;
-            // Fall through to WaveSurfer playback
-          }
-        }
-
-        // Standard playback path — ensure WaveSurfer is unmuted
-        if (!isUsingNativePlaybackRef.current) {
-          wavesurfer.setMuted(false);
-          wavesurfer.setVolume(usePlayerStore.getState().volume);
-        }
-
-        // Only auto-play if shouldAutoPlay flag is set (user explicitly clicked to play)
-        const shouldAutoPlayNow = usePlayerStore.getState().shouldAutoPlay;
-        if (shouldAutoPlayNow) {
-          // Clear the flag first
-          usePlayerStore.getState().clearAutoPlayFlag();
-
-          // Use a small delay to ensure audio element is fully ready
-          setTimeout(() => {
-            wavesurfer.play().catch((error) => {
-              debug.error('Failed to autoplay:', error);
-              // Don't show error for autoplay failures (browser restrictions)
-            });
-          }, 100);
-        } else {
-          debug.log('Skipping auto-play - shouldAutoPlay is false');
-        }
-      });
-
-      // Handle play/pause
-      wavesurfer.on('play', () => {
-        setIsPlaying(true);
-      });
-      wavesurfer.on('pause', () => setIsPlaying(false));
-      wavesurfer.on('finish', () => {
-        // Check loop state from store
-        const loop = usePlayerStore.getState().isLooping;
-        if (loop) {
-          wavesurfer.seekTo(0);
-          wavesurfer.play();
-        } else {
-          setIsPlaying(false);
-          // Trigger finish callback if set
-          const onFinish = usePlayerStore.getState().onFinish;
-          if (onFinish) {
-            onFinish();
-          }
-        }
-      });
-
-      // Handle errors
-      wavesurfer.on('error', (error) => {
-        debug.error('WaveSurfer error:', error);
-        setIsLoading(false);
-        setError(`Audio error: ${error instanceof Error ? error.message : String(error)}`);
-      });
-
-      // Handle loading
-      wavesurfer.on('loading', (percent) => {
-        setIsLoading(true);
-        if (percent === 100) {
           setIsLoading(false);
-        }
+          setError(`Audio error: ${err instanceof Error ? err.message : String(err)}`);
-      });
+        });
 
-      // Load audio immediately if audioUrl is already set
+        wavesurfer.on('loading', (percent) => {
-      if (audioUrl) {
+          setIsLoading(true);
-        debug.log('WaveSurfer ready, loading audio:', audioUrl);
+          if (percent === 100) setIsLoading(false);
-        loadingRef.current = true;
+        });
-        setIsLoading(true);
+
-        // Stop any current playback before loading new audio
+        wavesurferRef.current = wavesurfer;
-        if (wavesurfer.isPlaying()) {
+        setWsReady(true);
-          wavesurfer.pause();
+        debug.log('WaveSurfer created successfully');
-        }
+      } catch (err) {
-        wavesurfer
+        debug.error('Failed to create WaveSurfer:', err);
-          .load(audioUrl)
+        setError(
-          .then(() => {
+          `Failed to initialize waveform: ${err instanceof Error ? err.message : String(err)}`,
-            debug.log('Audio loaded into WaveSurfer');
+        );
-            loadingRef.current = false;
-          })
-          .catch((error) => {
-            debug.error('Failed to load audio into WaveSurfer:', error);
-            loadingRef.current = false;
-            setIsLoading(false);
-            setError(
-              `Failed to load audio: ${error instanceof Error ? error.message : String(error)}`,
-            );
-          });
       }
     };
 
-    // Use double requestAnimationFrame to ensure DOM is fully rendered
+    let rafId: number;
-    let rafId1: number;
+    rafId = requestAnimationFrame(() => {
-    let rafId2: number;
+      initWaveSurfer();
-    let timeoutId: number | null = null;
-
-    rafId1 = requestAnimationFrame(() => {
-      rafId2 = requestAnimationFrame(() => {
-        // Add a small delay to ensure container is fully laid out
-        timeoutId = setTimeout(() => {
-          initWaveSurfer();
-        }, 10);
-      });
     });
 
     return () => {
-      debug.log('Cleaning up WaveSurfer initialization effect');
+      cancelAnimationFrame(rafId);
-      if (rafId1) cancelAnimationFrame(rafId1);
+    };
-      if (rafId2) cancelAnimationFrame(rafId2);
+    // Only run on mount-like conditions. audioUrl is here so we create the instance
-      if (timeoutId) clearTimeout(timeoutId);
+    // when the player first appears, but we guard against re-creation above.
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [audioUrl, setIsPlaying, setDuration, setCurrentTime]);
+
+  // Destroy WaveSurfer only on unmount
+  useEffect(() => {
+    return () => {
       if (wavesurferRef.current) {
-        debug.log('Destroying WaveSurfer instance');
+        debug.log('Destroying WaveSurfer instance (unmount)');
         try {
           wavesurferRef.current.destroy();
-        } catch (error) {
+        } catch (err) {
-          debug.error('Error destroying WaveSurfer:', error);
+          debug.error('Error destroying WaveSurfer:', err);
         }
         wavesurferRef.current = null;
+        setWsReady(false);
       }
     };
-  }, [audioUrl, setIsPlaying, setCurrentTime, setDuration]);
+  }, []);
 
-  // Load audio when URL changes (only if WaveSurfer is already initialized)
+  // Load audio when URL changes (reuses the existing WaveSurfer instance)
   useEffect(() => {
     const wavesurfer = wavesurferRef.current;
+    if (!wavesurfer || !wsReady) return;
 
-    if (!audioUrl || !wavesurfer) {
+    if (!audioUrl) {
-      // Reset state when no audio or WaveSurfer not ready
+      // No audio - pause and reset
-      if (!audioUrl && wavesurfer) {
+      wavesurfer.pause();
-        wavesurfer.pause();
+      wavesurfer.seekTo(0);
-        wavesurfer.seekTo(0);
+      loadingRef.current = false;
-        loadingRef.current = false;
+      setIsLoading(false);
-        setIsLoading(false);
+      setDuration(0);
-        setDuration(0);
+      setCurrentTime(0);
-        setCurrentTime(0);
+      setError(null);
-        setError(null);
+      isUsingNativePlaybackRef.current = false;
-        // Reset native playback flag
-        isUsingNativePlaybackRef.current = false;
-      }
       return;
     }
 
-    // Stop native playback if it was active
+    // Reset native playback state
-    if (isUsingNativePlaybackRef.current && platform.metadata.isTauri) {
-      try {
-        platform.audio.stopPlayback();
-        debug.log('Stopped native audio playback');
-      } catch (error) {
-        debug.error('Failed to stop native playback:', error);
-      }
-    }
-
-    // Reset native playback flag when loading new audio
-    // Unmute WaveSurfer if it was muted for native playback
-    if (isUsingNativePlaybackRef.current) {
-      wavesurfer.setMuted(false);
-      wavesurfer.setVolume(usePlayerStore.getState().volume);
-    }
     isUsingNativePlaybackRef.current = false;
+    wavesurfer.setMuted(false);
+    wavesurfer.setVolume(usePlayerStore.getState().volume);
 
-    // CRITICAL: Force stop any current playback and cancel any pending loads
+    // Stop current playback and reset position before loading new audio.
-    // This must happen BEFORE any early returns
+    // With the WebAudio backend, pause() accumulates playedDuration internally.
-    debug.log('Audio URL changed to:', audioUrl);
+    // seekTo(0) resets it so the new track starts from the beginning.
-
+    debug.log('Loading new audio URL:', audioUrl);
-    // COMPLETELY stop and destroy the current audio
     try {
-      // First pause if playing
       if (wavesurfer.isPlaying()) {
-        debug.log('Pausing current playback');
         wavesurfer.pause();
       }
-
+      wavesurfer.seekTo(0);
-      // Use empty() to completely destroy the waveform and reset media
+    } catch (err) {
-      debug.log('Calling wavesurfer.empty() to destroy audio');
+      debug.error('Error resetting before load:', err);
-      wavesurfer.empty();
-    } catch (error) {
-      debug.error('Error stopping previous audio:', error);
-      // Continue anyway to load new audio
     }
 
-    // Reset loading state to allow new load (cancel any pending loads)
-    loadingRef.current = false;
-
-    // Now start the new load
     loadingRef.current = true;
     setIsLoading(true);
     setError(null);
     setCurrentTime(0);
     setDuration(0);
 
-    // Load new audio
-    debug.log('Starting new audio load for:', audioUrl);
     wavesurfer
       .load(audioUrl)
       .then(() => {
-        debug.log('Audio load promise resolved');
+        debug.log('Audio loaded into WaveSurfer');
-        // Don't set loading to false here - wait for 'ready' event
+        loadingRef.current = false;
       })
-      .catch((error) => {
+      .catch((err) => {
-        debug.error('Failed to load audio:', error);
+        debug.error('Failed to load audio:', err);
-        debug.error('Audio URL:', audioUrl);
         loadingRef.current = false;
         setIsLoading(false);
-        setError(`Failed to load audio: ${error instanceof Error ? error.message : String(error)}`);
+        setError(`Failed to load audio: ${err instanceof Error ? err.message : String(err)}`);
       });
-  }, [audioUrl, setCurrentTime, setDuration]);
+  }, [audioUrl, wsReady, setCurrentTime, setDuration]);
 
   // Sync play/pause state (only when user clicks play/pause button, not auto-sync)
   // This effect is kept for external state changes but should be minimal
@@ -520,7 +318,6 @@ export function AudioPlayer() {
     if (!wavesurferRef.current || duration === 0) return;
 
     if (isPlaying && wavesurferRef.current.isPlaying() === false) {
-      // Only auto-play if audio is ready
       wavesurferRef.current.play().catch((error) => {
         debug.error('Failed to play:', error);
         setIsPlaying(false);
@@ -534,14 +331,7 @@ export function AudioPlayer() {
   // Sync volume
   useEffect(() => {
     if (wavesurferRef.current) {
-      // If using native playback, keep WaveSurfer muted regardless of volume setting
+      wavesurferRef.current.setVolume(volume);
-      if (isUsingNativePlaybackRef.current) {
-        wavesurferRef.current.setVolume(0);
-        debug.log('Volume sync: Using native playback, keeping WaveSurfer muted');
-      } else {
-        wavesurferRef.current.setVolume(volume);
-        debug.log('Volume synced:', volume);
-      }
     }
   }, [volume]);
 
@@ -566,7 +356,6 @@ export function AudioPlayer() {
       return;
     }
 
-    // Reset to beginning and play
     debug.log('Restarting current audio from beginning');
     wavesurfer.seekTo(0);
     wavesurfer.play().catch((error) => {
@@ -575,34 +364,35 @@ export function AudioPlayer() {
       setError(`Playback error: ${error instanceof Error ? error.message : String(error)}`);
     });
 
-    // Clear the restart flag
     clearRestartFlag();
   }, [shouldRestart, duration, setIsPlaying, clearRestartFlag]);
 
-  // Handle shouldAutoPlay flag - for story mode auto-advance
+  // Auto-play is handled exclusively in the WaveSurfer 'ready' event handler.
-  const shouldAutoPlay = usePlayerStore((state) => state.shouldAutoPlay);
+  // A separate effect here would race with the ready event since the WebAudio
-  const clearAutoPlayFlag = usePlayerStore((state) => state.clearAutoPlayFlag);
+  // backend needs to fully decode the audio before play() works correctly.
 
+  // Spacebar to play/pause (capture phase so it fires before focused elements)
   useEffect(() => {
-    const wavesurfer = wavesurferRef.current;
+    const onKeyDown = (e: KeyboardEvent) => {
-    if (!wavesurfer || !shouldAutoPlay || duration === 0) {
+      if (e.code !== 'Space') return;
-      return;
+      // Ignore if user is typing in an input/textarea
-    }
+      const tag = (e.target as HTMLElement)?.tagName;
-
+      if (tag === 'INPUT' || tag === 'TEXTAREA' || (e.target as HTMLElement)?.isContentEditable) {
-    // Auto-play the newly loaded audio
+        return;
-    debug.log('Auto-playing next track in story mode');
+      }
-    wavesurfer.seekTo(0);
+      if (audioUrl && duration > 0 && wavesurferRef.current) {
-    wavesurfer.play().catch((error) => {
+        e.preventDefault();
-      debug.error('Failed to auto-play:', error);
+        e.stopPropagation();
-      setIsPlaying(false);
+        if (wavesurferRef.current.isPlaying()) {
-      setError(`Playback error: ${error instanceof Error ? error.message : String(error)}`);
+          wavesurferRef.current.pause();
-    });
+        } else {
-
+          wavesurferRef.current.play().catch((err) => debug.error('Spacebar play failed:', err));
-    // Clear the auto-play flag
+        }
-    clearAutoPlayFlag();
+      }
-  }, [shouldAutoPlay, duration, setIsPlaying, clearAutoPlayFlag]);
+    };
-
+    document.addEventListener('keydown', onKeyDown, true);
-  // Handle loop - WaveSurfer handles this via the 'finish' event
+    return () => document.removeEventListener('keydown', onKeyDown, true);
+  }, [audioUrl, duration]);
 
   const handlePlayPause = async () => {
     // Standard WaveSurfer playback (works for both normal and native playback modes)
@@ -741,32 +531,32 @@ export function AudioPlayer() {
             size="icon"
             onClick={handlePlayPause}
             disabled={isLoading || duration === 0}
-            className="shrink-0"
+            className={`shrink-0 -mt-2 ${isPlaying ? 'bg-accent text-accent-foreground' : ''}`}
             title={duration === 0 && !isLoading ? 'Audio not loaded' : ''}
             aria-label={
               duration === 0 && !isLoading ? 'Audio not loaded' : isPlaying ? 'Pause' : 'Play'
             }
           >
-            {isPlaying ? <Pause className="h-5 w-5" /> : <Play className="h-5 w-5" />}
+            {isPlaying ? (
+              <Pause className="h-5 w-5 fill-current" />
+            ) : (
+              <Play className="h-5 w-5 fill-current" />
+            )}
           </Button>
 
           {/* Waveform */}
           <div className="flex-1 min-w-0 flex flex-col gap-1">
-            <div ref={waveformRef} className="w-full min-h-[80px]" />
+            <div ref={waveformRef} className="w-full min-h-[80px] select-none" />
-            {duration > 0 && (
+            <Slider
-              <Slider
+              value={duration > 0 ? [(currentTime / duration) * 100] : [0]}
-                value={duration > 0 ? [(currentTime / duration) * 100] : [0]}
+              onValueChange={handleSeek}
-                onValueChange={handleSeek}
+              max={100}
-                max={100}
+              step={0.1}
-                step={0.1}
+              className="w-full"
-                className="w-full"
+              aria-label="Playback position"
-                aria-label="Playback position"
+              aria-valuetext={`${formatAudioDuration(currentTime)} of ${formatAudioDuration(duration)}`}
-                aria-valuetext={`${formatAudioDuration(currentTime)} of ${formatAudioDuration(duration)}`}
+            />
-              />
+
-            )}
-            {isLoading && (
-              <div className="text-xs text-muted-foreground text-center py-2">Loading audio...</div>
-            )}
             {error && <div className="text-xs text-destructive text-center py-2">{error}</div>}
           </div>
 
@@ -777,19 +567,12 @@ export function AudioPlayer() {
             <span className="font-mono">{formatAudioDuration(duration)}</span>
           </div>
 
-          {/* Title */}
-          {title && (
-            <div className="text-sm font-medium truncate max-w-[200px] shrink-0 hidden lg:block">
-              {title}
-            </div>
-          )}
-
           {/* Loop Button */}
           <Button
             variant="ghost"
             size="icon"
             onClick={toggleLoop}
-            className={isLooping ? 'text-primary' : ''}
+            className={isLooping ? 'bg-accent text-accent-foreground' : ''}
             title="Toggle loop"
             aria-label={isLooping ? 'Stop looping' : 'Loop'}
           >

app/src/components/Generation/EngineModelSelector.tsx

@@ -0,0 +1,103 @@
+import type { UseFormReturn } from 'react-hook-form';
+import { FormControl } from '@/components/ui/form';
+import {
+  Select,
+  SelectContent,
+  SelectItem,
+  SelectTrigger,
+  SelectValue,
+} from '@/components/ui/select';
+import { getLanguageOptionsForEngine } from '@/lib/constants/languages';
+import type { GenerationFormValues } from '@/lib/hooks/useGenerationForm';
+
+/**
+ * Engine/model options and their display metadata.
+ * Adding a new engine means adding one entry here.
+ */
+const ENGINE_OPTIONS = [
+  { value: 'qwen:1.7B', label: 'Qwen3-TTS 1.7B' },
+  { value: 'qwen:0.6B', label: 'Qwen3-TTS 0.6B' },
+  { value: 'luxtts', label: 'LuxTTS' },
+  { value: 'chatterbox', label: 'Chatterbox' },
+  { value: 'chatterbox_turbo', label: 'Chatterbox Turbo' },
+] as const;
+
+const ENGINE_DESCRIPTIONS: Record<string, string> = {
+  qwen: 'Multi-language, two sizes',
+  luxtts: 'Fast, English-focused',
+  chatterbox: '23 languages, incl. Hebrew',
+  chatterbox_turbo: 'English, [laugh] [cough] tags',
+};
+
+/** Engines that only support English and should force language to 'en' on select. */
+const ENGLISH_ONLY_ENGINES = new Set(['luxtts', 'chatterbox_turbo']);
+
+function getSelectValue(engine: string, modelSize?: string): string {
+  if (engine === 'qwen') return `qwen:${modelSize || '1.7B'}`;
+  return engine;
+}
+
+function handleEngineChange(form: UseFormReturn<GenerationFormValues>, value: string) {
+  if (value.startsWith('qwen:')) {
+    const [, modelSize] = value.split(':');
+    form.setValue('engine', 'qwen');
+    form.setValue('modelSize', modelSize as '1.7B' | '0.6B');
+    // Validate language is supported by Qwen
+    const currentLang = form.getValues('language');
+    const available = getLanguageOptionsForEngine('qwen');
+    if (!available.some((l) => l.value === currentLang)) {
+      form.setValue('language', available[0]?.value ?? 'en');
+    }
+  } else {
+    form.setValue('engine', value as GenerationFormValues['engine']);
+    form.setValue('modelSize', undefined as unknown as '1.7B' | '0.6B');
+    if (ENGLISH_ONLY_ENGINES.has(value)) {
+      form.setValue('language', 'en');
+    } else {
+      // If current language isn't supported by the new engine, reset to first available
+      const currentLang = form.getValues('language');
+      const available = getLanguageOptionsForEngine(value);
+      if (!available.some((l) => l.value === currentLang)) {
+        form.setValue('language', available[0]?.value ?? 'en');
+      }
+    }
+  }
+}
+
+interface EngineModelSelectorProps {
+  form: UseFormReturn<GenerationFormValues>;
+  compact?: boolean;
+}
+
+export function EngineModelSelector({ form, compact }: EngineModelSelectorProps) {
+  const engine = form.watch('engine') || 'qwen';
+  const modelSize = form.watch('modelSize');
+  const selectValue = getSelectValue(engine, modelSize);
+
+  const itemClass = compact ? 'text-xs text-muted-foreground' : undefined;
+  const triggerClass = compact
+    ? 'h-8 text-xs bg-card border-border rounded-full hover:bg-background/50 transition-all'
+    : undefined;
+
+  return (
+    <Select value={selectValue} onValueChange={(v) => handleEngineChange(form, v)}>
+      <FormControl>
+        <SelectTrigger className={triggerClass}>
+          <SelectValue />
+        </SelectTrigger>
+      </FormControl>
+      <SelectContent>
+        {ENGINE_OPTIONS.map((opt) => (
+          <SelectItem key={opt.value} value={opt.value} className={itemClass}>
+            {opt.label}
+          </SelectItem>
+        ))}
+      </SelectContent>
+    </Select>
+  );
+}
+
+/** Returns a human-readable description for the currently selected engine. */
+export function getEngineDescription(engine: string): string {
+  return ENGINE_DESCRIPTIONS[engine] ?? '';
+}

app/src/components/Generation/FloatingGenerateBox.tsx

@@ -1,8 +1,8 @@
+import { useQuery } from '@tanstack/react-query';
 import { useMatchRoute } from '@tanstack/react-router';
 import { AnimatePresence, motion } from 'framer-motion';
-import { Loader2, SlidersHorizontal, Sparkles } from 'lucide-react';
+import { Loader2, Sparkles } from 'lucide-react';
 import { useEffect, useRef, useState } from 'react';
-import { EffectsChainEditor } from '@/components/Effects/EffectsChainEditor';
 import { Button } from '@/components/ui/button';
 import { Form, FormControl, FormField, FormItem, FormMessage } from '@/components/ui/form';
 import {
@@ -13,7 +13,7 @@ import {
   SelectValue,
 } from '@/components/ui/select';
 import { Textarea } from '@/components/ui/textarea';
-import type { EffectConfig } from '@/lib/api/types';
+import { apiClient } from '@/lib/api/client';
 import { getLanguageOptionsForEngine, type LanguageCode } from '@/lib/constants/languages';
 import { useGenerationForm } from '@/lib/hooks/useGenerationForm';
 import { useProfile, useProfiles } from '@/lib/hooks/useProfiles';
@@ -22,6 +22,7 @@ import { cn } from '@/lib/utils/cn';
 import { useGenerationStore } from '@/stores/generationStore';
 import { useStoryStore } from '@/stores/storyStore';
 import { useUIStore } from '@/stores/uiStore';
+import { EngineModelSelector } from './EngineModelSelector';
 import { ParalinguisticInput } from './ParalinguisticInput';
 
 interface FloatingGenerateBoxProps {
@@ -38,8 +39,7 @@ export function FloatingGenerateBox({
   const { data: selectedProfile } = useProfile(selectedProfileId || '');
   const { data: profiles } = useProfiles();
   const [isExpanded, setIsExpanded] = useState(false);
-  const [isInstructMode, setIsInstructMode] = useState(false);
+  const [selectedPresetId, setSelectedPresetId] = useState<string | null>(null);
-  const [effectsChain, setEffectsChain] = useState<EffectConfig[]>([]);
   const containerRef = useRef<HTMLDivElement>(null);
   const textareaRef = useRef<HTMLTextAreaElement | null>(null);
   const matchRoute = useMatchRoute();
@@ -49,18 +49,28 @@ export function FloatingGenerateBox({
   const { data: currentStory } = useStory(selectedStoryId);
   const addPendingStoryAdd = useGenerationStore((s) => s.addPendingStoryAdd);
 
+  // Fetch effect presets for the dropdown
+  const { data: effectPresets } = useQuery({
+    queryKey: ['effectPresets'],
+    queryFn: () => apiClient.listEffectPresets(),
+  });
+
   // Calculate if track editor is visible (on stories route with items)
   const hasTrackEditor = isStoriesRoute && currentStory && currentStory.items.length > 0;
 
   const { form, handleSubmit, isPending } = useGenerationForm({
     onSuccess: async (generationId) => {
       setIsExpanded(false);
-      // Defer the story add until TTS completes — useGenerationProgress handles it
+      // Defer the story add until TTS completes -- useGenerationProgress handles it
       if (isStoriesRoute && selectedStoryId && generationId) {
         addPendingStoryAdd(generationId, selectedStoryId);
       }
     },
-    getEffectsChain: () => (effectsChain.length > 0 ? effectsChain : undefined),
+    getEffectsChain: () => {
+      if (!selectedPresetId || !effectPresets) return undefined;
+      const preset = effectPresets.find((p) => p.id === selectedPresetId);
+      return preset?.effects_chain;
+    },
   });
 
   // Click away handler to collapse the box
@@ -188,111 +198,57 @@ export function FloatingGenerateBox({
         <Form {...form}>
           <form onSubmit={form.handleSubmit(onSubmit)}>
             <div className="flex gap-2">
-              <motion.div
+              <motion.div className="flex-1" transition={{ duration: 0.3, ease: 'easeOut' }}>
-                className={cn('flex-1', isExpanded && 'mr-12')}
+                <FormField
-                transition={{ duration: 0.3, ease: 'easeOut' }}
+                  control={form.control}
-              >
+                  name="text"
-                {/* Text field - hidden when in instruct mode */}
+                  render={({ field }) => (
-                <div style={{ display: isInstructMode ? 'none' : 'block' }}>
+                    <FormItem>
-                  <FormField
+                      <FormControl>
-                    control={form.control}
+                        <motion.div
-                    name="text"
+                          animate={{
-                    render={({ field }) => (
+                            height: isExpanded ? 'auto' : '32px',
-                      <FormItem>
+                          }}
-                        <FormControl>
+                          transition={{ duration: 0.15, ease: 'easeOut' }}
-                          <motion.div
+                          style={{ overflow: 'hidden' }}
-                            animate={{
+                        >
-                              height: isExpanded ? 'auto' : '32px',
+                          {form.watch('engine') === 'chatterbox_turbo' ? (
-                            }}
+                            <ParalinguisticInput
-                            transition={{ duration: 0.15, ease: 'easeOut' }}
+                              value={field.value}
-                            style={{ overflow: 'hidden' }}
+                              onChange={field.onChange}
-                          >
+                              placeholder={
-                            {form.watch('engine') === 'chatterbox_turbo' ? (
+                                isStoriesRoute && currentStory
-                              <ParalinguisticInput
+                                  ? `Generate speech for "${currentStory.name}"... (type / for effects)`
-                                value={field.value}
+                                  : selectedProfile
-                                onChange={field.onChange}
+                                    ? `Type / for effects like [laugh], [sigh]...`
-                                placeholder={
+                                    : 'Select a voice profile above...'
-                                  isStoriesRoute && currentStory
+                              }
-                                    ? `Generate speech for "${currentStory.name}"... (type / for effects)`
+                              className="px-3 py-2 resize-none bg-transparent border-none focus-visible:ring-0 focus-visible:ring-offset-0 focus:outline-none focus:ring-0 outline-none ring-0 rounded-2xl text-sm w-full"
-                                    : selectedProfile
+                              style={{
-                                      ? `Type / for effects like [laugh], [sigh]...`
+                                minHeight: isExpanded ? '100px' : '32px',
-                                      : 'Select a voice profile above...'
+                                maxHeight: '300px',
-                                }
+                                overflowY: 'auto',
-                                className="px-3 py-2 resize-none bg-transparent border-none focus-visible:ring-0 focus-visible:ring-offset-0 focus:outline-none focus:ring-0 outline-none ring-0 rounded-2xl text-sm w-full"
+                              }}
-                                style={{
+                              disabled={!selectedProfileId}
-                                  minHeight: isExpanded ? '100px' : '32px',
+                              onClick={() => setIsExpanded(true)}
-                                  maxHeight: '300px',
+                              onFocus={() => setIsExpanded(true)}
-                                  overflowY: 'auto',
+                            />
-                                }}
+                          ) : (
-                                disabled={!selectedProfileId}
-                                onClick={() => setIsExpanded(true)}
-                                onFocus={() => setIsExpanded(true)}
-                              />
-                            ) : (
-                              <Textarea
-                                {...field}
-                                ref={(node: HTMLTextAreaElement | null) => {
-                                  // Store ref for auto-resize (only for active field)
-                                  if (!isInstructMode) {
-                                    textareaRef.current = node;
-                                  }
-                                  // Forward ref to react-hook-form
-                                  if (typeof field.ref === 'function') {
-                                    field.ref(node);
-                                  }
-                                }}
-                                placeholder={
-                                  isStoriesRoute && currentStory
-                                    ? `Generate speech for "${currentStory.name}"...`
-                                    : selectedProfile
-                                      ? `Generate speech using ${selectedProfile.name}...`
-                                      : 'Select a voice profile above...'
-                                }
-                                className="resize-none bg-transparent border-none focus-visible:ring-0 focus-visible:ring-offset-0 focus:outline-none focus:ring-0 outline-none ring-0 rounded-2xl text-sm placeholder:text-muted-foreground/60 w-full"
-                                style={{
-                                  minHeight: isExpanded ? '100px' : '32px',
-                                  maxHeight: '300px',
-                                }}
-                                disabled={!selectedProfileId}
-                                onClick={() => setIsExpanded(true)}
-                                onFocus={() => setIsExpanded(true)}
-                              />
-                            )}
-                          </motion.div>
-                        </FormControl>
-                        <FormMessage className="text-xs" />
-                      </FormItem>
-                    )}
-                  />
-                </div>
-                {/* Instruct field - hidden when in text mode */}
-                <div style={{ display: isInstructMode ? 'block' : 'none' }}>
-                  <FormField
-                    control={form.control}
-                    name="instruct"
-                    render={({ field }) => (
-                      <FormItem>
-                        <FormControl>
-                          <motion.div
-                            animate={{
-                              height: isExpanded ? 'auto' : '32px',
-                            }}
-                            transition={{ duration: 0.15, ease: 'easeOut' }}
-                            style={{ overflow: 'hidden' }}
-                          >
                             <Textarea
                               {...field}
                               ref={(node: HTMLTextAreaElement | null) => {
-                                // Store ref for auto-resize (only for active field)
+                                textareaRef.current = node;
-                                if (isInstructMode) {
-                                  textareaRef.current = node;
-                                }
-                                // Forward ref to react-hook-form
                                 if (typeof field.ref === 'function') {
                                   field.ref(node);
                                 }
                               }}
-                              placeholder="e.g. very happy and excited"
+                              placeholder={
+                                isStoriesRoute && currentStory
+                                  ? `Generate speech for "${currentStory.name}"...`
+                                  : selectedProfile
+                                    ? `Generate speech using ${selectedProfile.name}...`
+                                    : 'Select a voice profile above...'
+                              }
                               className="resize-none bg-transparent border-none focus-visible:ring-0 focus-visible:ring-offset-0 focus:outline-none focus:ring-0 outline-none ring-0 rounded-2xl text-sm placeholder:text-muted-foreground/60 w-full"
                               style={{
                                 minHeight: isExpanded ? '100px' : '32px',
@@ -302,13 +258,13 @@ export function FloatingGenerateBox({
                               onClick={() => setIsExpanded(true)}
                               onFocus={() => setIsExpanded(true)}
                             />
-                          </motion.div>
+                          )}
-                        </FormControl>
+                        </motion.div>
-                        <FormMessage className="text-xs" />
+                      </FormControl>
-                      </FormItem>
+                      <FormMessage className="text-xs" />
-                    )}
+                    </FormItem>
-                  />
+                  )}
-                </div>
+                />
               </motion.div>
 
               <div className="relative shrink-0">
@@ -340,62 +296,9 @@ export function FloatingGenerateBox({
                         : 'Generate speech'}
                   </span>
                 </div>
-                <AnimatePresence>
-                  {isExpanded && form.watch('engine') === 'qwen' && (
-                    <motion.div
-                      initial={{ opacity: 0, scale: 0.8 }}
-                      animate={{ opacity: 1, scale: 1 }}
-                      exit={{ opacity: 0, scale: 0.8 }}
-                      transition={{ duration: 0.2 }}
-                      className="absolute top-0 right-[calc(100%+0.5rem)]"
-                    >
-                      <div className="group relative">
-                        <Button
-                          type="button"
-                          variant="ghost"
-                          size="icon"
-                          onClick={() => setIsInstructMode(!isInstructMode)}
-                          className={cn(
-                            'h-10 w-10 rounded-full transition-all duration-200',
-                            isInstructMode
-                              ? 'bg-accent text-accent-foreground border border-accent hover:bg-accent/90'
-                              : effectsChain.length > 0
-                                ? 'bg-accent/50 text-accent-foreground border border-accent/50 hover:bg-accent/70'
-                                : 'bg-card border border-border hover:bg-background/50',
-                          )}
-                          aria-label={
-                            isInstructMode ? 'Fine tune instructions, on' : 'Fine tune instructions'
-                          }
-                        >
-                          <SlidersHorizontal className="h-4 w-4" />
-                        </Button>
-                        <span className="pointer-events-none absolute bottom-full left-1/2 -translate-x-1/2 mb-2 whitespace-nowrap rounded-md bg-popover px-3 py-1.5 text-xs text-popover-foreground border border-border opacity-0 transition-opacity group-hover:opacity-100 z-[9999]">
-                          Fine tune instructions & effects
-                        </span>
-                      </div>
-                    </motion.div>
-                  )}
-                </AnimatePresence>
               </div>
             </div>
 
-            {/* Effects chain editor panel - shown alongside instruct */}
-            <AnimatePresence>
-              {isExpanded && isInstructMode && (
-                <motion.div
-                  initial={{ height: 0, opacity: 0 }}
-                  animate={{ height: 'auto', opacity: 1 }}
-                  exit={{ height: 0, opacity: 0 }}
-                  transition={{ duration: 0.2 }}
-                  className="overflow-hidden mt-2"
-                >
-                  <div className="border-t border-border/50 pt-2 pb-1">
-                    <EffectsChainEditor value={effectsChain} onChange={setEffectsChain} compact />
-                  </div>
-                </motion.div>
-              )}
-            </AnimatePresence>
-
             <AnimatePresence>
               <motion.div
                 initial={{ height: 0, opacity: 0 }}
@@ -454,57 +357,29 @@ export function FloatingGenerateBox({
                     }}
                   />
 
+                  <FormItem className="flex-1 space-y-0">
+                    <EngineModelSelector form={form} compact />
+                  </FormItem>
+
                   <FormItem className="flex-1 space-y-0">
                     <Select
-                      value={
+                      value={selectedPresetId || 'none'}
-                        form.watch('engine') === 'luxtts'
+                      onValueChange={(value) =>
-                          ? 'luxtts'
+                        setSelectedPresetId(value === 'none' ? null : value)
-                          : form.watch('engine') === 'chatterbox'
-                            ? 'chatterbox'
-                            : form.watch('engine') === 'chatterbox_turbo'
-                              ? 'chatterbox_turbo'
-                              : `qwen:${form.watch('modelSize') || '1.7B'}`
                       }
-                      onValueChange={(value) => {
-                        if (value === 'luxtts') {
-                          form.setValue('engine', 'luxtts');
-                          form.setValue('language', 'en');
-                        } else if (value === 'chatterbox') {
-                          form.setValue('engine', 'chatterbox');
-                        } else if (value === 'chatterbox_turbo') {
-                          form.setValue('engine', 'chatterbox_turbo');
-                          form.setValue('language', 'en');
-                        } else {
-                          const [, modelSize] = value.split(':');
-                          form.setValue('engine', 'qwen');
-                          form.setValue('modelSize', modelSize as '1.7B' | '0.6B');
-                        }
-                      }}
                     >
-                      <FormControl>
+                      <SelectTrigger className="h-8 text-xs bg-card border-border rounded-full hover:bg-background/50 transition-all">
-                        <SelectTrigger className="h-8 text-xs bg-card border-border rounded-full hover:bg-background/50 transition-all">
+                        <SelectValue placeholder="No effects" />
-                          <SelectValue />
+                      </SelectTrigger>
-                        </SelectTrigger>
-                      </FormControl>
                       <SelectContent>
-                        <SelectItem value="qwen:1.7B" className="text-xs text-muted-foreground">
+                        <SelectItem value="none" className="text-xs">
-                          Qwen3-TTS 1.7B
+                          No effects
-                        </SelectItem>
-                        <SelectItem value="qwen:0.6B" className="text-xs text-muted-foreground">
-                          Qwen3-TTS 0.6B
-                        </SelectItem>
-                        <SelectItem value="luxtts" className="text-xs text-muted-foreground">
-                          LuxTTS
-                        </SelectItem>
-                        <SelectItem value="chatterbox" className="text-xs text-muted-foreground">
-                          Chatterbox
-                        </SelectItem>
-                        <SelectItem
-                          value="chatterbox_turbo"
-                          className="text-xs text-muted-foreground"
-                        >
-                          Chatterbox Turbo
                         </SelectItem>
+                        {effectPresets?.map((preset) => (
+                          <SelectItem key={preset.id} value={preset.id} className="text-xs">
+                            {preset.name}
+                          </SelectItem>
+                        ))}
                       </SelectContent>
                     </Select>
                   </FormItem>

app/src/components/Generation/GenerationForm.tsx

@@ -23,6 +23,7 @@ import { getLanguageOptionsForEngine } from '@/lib/constants/languages';
 import { useGenerationForm } from '@/lib/hooks/useGenerationForm';
 import { useProfile } from '@/lib/hooks/useProfiles';
 import { useUIStore } from '@/stores/uiStore';
+import { EngineModelSelector, getEngineDescription } from './EngineModelSelector';
 import { ParalinguisticInput } from './ParalinguisticInput';
 
 export function GenerationForm() {
@@ -117,53 +118,9 @@ export function GenerationForm() {
             <div className="grid gap-4 md:grid-cols-3">
               <FormItem>
                 <FormLabel>Model</FormLabel>
-                <Select
+                <EngineModelSelector form={form} />
-                  value={
-                    form.watch('engine') === 'luxtts'
-                      ? 'luxtts'
-                      : form.watch('engine') === 'chatterbox'
-                        ? 'chatterbox'
-                        : form.watch('engine') === 'chatterbox_turbo'
-                          ? 'chatterbox_turbo'
-                          : `qwen:${form.watch('modelSize') || '1.7B'}`
-                  }
-                  onValueChange={(value) => {
-                    if (value === 'luxtts') {
-                      form.setValue('engine', 'luxtts');
-                      form.setValue('language', 'en');
-                    } else if (value === 'chatterbox') {
-                      form.setValue('engine', 'chatterbox');
-                    } else if (value === 'chatterbox_turbo') {
-                      form.setValue('engine', 'chatterbox_turbo');
-                      form.setValue('language', 'en');
-                    } else {
-                      const [, modelSize] = value.split(':');
-                      form.setValue('engine', 'qwen');
-                      form.setValue('modelSize', modelSize as '1.7B' | '0.6B');
-                    }
-                  }}
-                >
-                  <FormControl>
-                    <SelectTrigger>
-                      <SelectValue />
-                    </SelectTrigger>
-                  </FormControl>
-                  <SelectContent>
-                    <SelectItem value="qwen:1.7B">Qwen3-TTS 1.7B</SelectItem>
-                    <SelectItem value="qwen:0.6B">Qwen3-TTS 0.6B</SelectItem>
-                    <SelectItem value="luxtts">LuxTTS</SelectItem>
-                    <SelectItem value="chatterbox">Chatterbox</SelectItem>
-                    <SelectItem value="chatterbox_turbo">Chatterbox Turbo</SelectItem>
-                  </SelectContent>
-                </Select>
                 <FormDescription>
-                  {form.watch('engine') === 'luxtts'
+                  {getEngineDescription(form.watch('engine') || 'qwen')}
-                    ? 'Fast, English-focused'
-                    : form.watch('engine') === 'chatterbox'
-                      ? '23 languages, incl. Hebrew'
-                      : form.watch('engine') === 'chatterbox_turbo'
-                        ? 'English, [laugh] [cough] tags'
-                        : 'Multi-language, two sizes'}
                 </FormDescription>
               </FormItem>
 

app/src/components/History/HistoryTable.tsx

@@ -15,7 +15,7 @@ import {
   Wand2,
 } from 'lucide-react';
 import { useEffect, useRef, useState } from 'react';
-import Loader from 'react-loaders';
+
 import { EffectsChainEditor } from '@/components/Effects/EffectsChainEditor';
 import { Button } from '@/components/ui/button';
 import {
@@ -56,8 +56,35 @@ import { formatDate, formatDuration, formatEngineName } from '@/lib/utils/format
 import { useGenerationStore } from '@/stores/generationStore';
 import { usePlayerStore } from '@/stores/playerStore';
 
-// OLD TABLE-BASED COMPONENT - REMOVED (can be found in git history)
+// ─── Audio Bars ─────────────────────────────────────────────────────────────
-// This is the new alternate history view with fixed height rows
+
+function AudioBars({ mode }: { mode: 'idle' | 'generating' | 'playing' }) {
+  const barColor = mode !== 'idle' ? 'bg-accent' : 'bg-muted-foreground/40';
+  return (
+    <div className="flex items-center gap-[2px] h-5">
+      {[0, 1, 2, 3, 4].map((i) => (
+        <motion.div
+          key={`${mode}-${i}`}
+          className={`w-[3px] rounded-full ${barColor}`}
+          animate={
+            mode === 'generating'
+              ? { height: ['6px', '16px', '6px'] }
+              : mode === 'playing'
+                ? { height: ['8px', '14px', '4px', '12px', '8px'] }
+                : { height: '8px' }
+          }
+          transition={
+            mode === 'generating'
+              ? { duration: 0.6, repeat: Infinity, delay: i * 0.08, ease: 'easeInOut' }
+              : mode === 'playing'
+                ? { duration: 1.2, repeat: Infinity, delay: i * 0.15, ease: 'easeInOut' }
+                : { duration: 0.4, ease: 'easeOut' }
+          }
+        />
+      ))}
+    </div>
+  );
+}
 
 // NEW ALTERNATE HISTORY VIEW - FIXED HEIGHT ROWS WITH INFINITE SCROLL
 export function HistoryTable() {
@@ -126,7 +153,9 @@ export function HistoryTable() {
     }
   }, [historyData, page]);
 
-  // Reset to page 0 when deletions or imports occur
+  // Reset to page 0 when deletions, imports, or generation completions occur
+  const pendingCount = useGenerationStore((state) => state.pendingGenerationIds.size);
+  const prevPendingCountRef = useRef(pendingCount);
   useEffect(() => {
     if (deleteGeneration.isSuccess || importGeneration.isSuccess) {
       setPage(0);
@@ -134,6 +163,19 @@ export function HistoryTable() {
     }
   }, [deleteGeneration.isSuccess, importGeneration.isSuccess]);
 
+  useEffect(() => {
+    // A generation finished (pending count decreased) — scroll back to show it
+    if (
+      prevPendingCountRef.current > 0 &&
+      pendingCount < prevPendingCountRef.current &&
+      page !== 0
+    ) {
+      setPage(0);
+      setAllHistory([]);
+    }
+    prevPendingCountRef.current = pendingCount;
+  }, [pendingCount, page]);
+
   // Intersection Observer for infinite scroll
   useEffect(() => {
     const loadMoreEl = loadMoreRef.current;
@@ -394,7 +436,8 @@ export function HistoryTable() {
           >
             {history.map((gen) => {
               const isCurrentlyPlaying = currentAudioId === gen.id && isPlaying;
-              const isGenerating = gen.status === 'generating';
+              const isInProgress = gen.status === 'loading_model' || gen.status === 'generating';
+              const isGenerating = isInProgress;
               const isFailed = gen.status === 'failed';
               const isPlayable = !isGenerating && !isFailed;
               const hasVersions = gen.versions && gen.versions.length > 1;
@@ -412,7 +455,7 @@ export function HistoryTable() {
                     role={isPlayable ? 'button' : undefined}
                     tabIndex={isPlayable ? 0 : undefined}
                     className={cn(
-                      'flex items-stretch gap-4 h-26 p-3',
+                      'flex items-stretch gap-4 h-26 p-3 outline-none',
                       isPlayable && 'hover:bg-muted/70 cursor-pointer rounded-md',
                       isVersionsExpanded && 'rounded-b-none',
                     )}
@@ -445,12 +488,9 @@ export function HistoryTable() {
                   >
                     {/* Status icon */}
                     <div className="flex items-center shrink-0 w-10 justify-center overflow-hidden">
-                      <div className="scale-50">
+                      <AudioBars
-                        <Loader
+                        mode={isGenerating ? 'generating' : isCurrentlyPlaying ? 'playing' : 'idle'}
-                          type={isGenerating ? 'line-scale' : 'line-scale-pulse-out-rapid'}
+                      />
-                          active={isGenerating || isCurrentlyPlaying}
-                        />
-                      </div>
                     </div>
 
                     {/* Left side - Meta information */}
@@ -472,8 +512,10 @@ export function HistoryTable() {
                         ) : null}
                       </div>
                       <div className="text-xs text-muted-foreground">
-                        {isGenerating ? (
+                        {isInProgress ? (
-                          <span className="text-accent">Generating...</span>
+                          <span className="text-accent">
+                            {gen.status === 'loading_model' ? 'Loading model...' : 'Generating...'}
+                          </span>
                         ) : (
                           formatDate(gen.created_at)
                         )}

app/src/components/ServerTab/AboutPage.tsx

@@ -0,0 +1,135 @@
+import { ArrowUpRight } from 'lucide-react';
+import type { CSSProperties, ReactNode } from 'react';
+import { useEffect, useState } from 'react';
+import voiceboxLogo from '@/assets/voicebox-logo.png';
+import { usePlatform } from '@/platform/PlatformContext';
+
+function FadeIn({ delay = 0, children }: { delay?: number; children: ReactNode }) {
+  return (
+    <div
+      className="animate-[fadeInUp_0.5s_ease_both]"
+      style={{ animationDelay: `${delay}ms` } as CSSProperties}
+    >
+      {children}
+    </div>
+  );
+}
+
+export function AboutPage() {
+  const platform = usePlatform();
+  const [version, setVersion] = useState('');
+
+  useEffect(() => {
+    platform.metadata
+      .getVersion()
+      .then(setVersion)
+      .catch(() => setVersion(''));
+  }, [platform]);
+
+  return (
+    <>
+      <style>{`
+        @keyframes fadeInUp {
+          from {
+            opacity: 0;
+            transform: translateY(8px);
+          }
+          to {
+            opacity: 1;
+            transform: translateY(0);
+          }
+        }
+      `}</style>
+      <div className="max-w-md mx-auto h-full flex items-center">
+        <div className="flex flex-col items-center text-center space-y-5">
+          <FadeIn delay={0}>
+            <img src={voiceboxLogo} alt="Voicebox" className="w-20 h-20 object-contain" />
+          </FadeIn>
+
+          <FadeIn delay={80}>
+            <div className="space-y-1.5">
+              <h1 className="text-lg font-semibold">Voicebox</h1>
+              <p className="text-xs text-muted-foreground/60 h-4">
+                {version ? `v${version}` : '\u00A0'}
+              </p>
+            </div>
+          </FadeIn>
+
+          <FadeIn delay={160}>
+            <p className="text-sm text-muted-foreground leading-relaxed max-w-sm">
+              The open-source voice synthesis studio. Clone voices, generate speech, apply effects,
+              and build voice-powered apps — all running locally on your machine.
+            </p>
+          </FadeIn>
+
+          <FadeIn delay={240}>
+            <div className="flex items-center gap-1.5 text-sm text-muted-foreground">
+              <span>Created by</span>
+              <a
+                href="https://github.com/jamiepine"
+                target="_blank"
+                rel="noopener noreferrer"
+                className="text-accent hover:underline"
+              >
+                Jamie Pine
+              </a>
+            </div>
+          </FadeIn>
+
+          <FadeIn delay={320}>
+            <div className="flex flex-wrap justify-center gap-3 pt-2">
+              <a
+                href="https://buymeacoffee.com/jamiepine"
+                target="_blank"
+                rel="noopener noreferrer"
+                className="group inline-flex items-center gap-2 rounded-lg border border-border/60 px-4 py-2 text-sm transition-colors hover:bg-muted/50"
+              >
+                <svg
+                  className="h-4 w-4 text-[#FFDD00]"
+                  viewBox="0 0 24 24"
+                  fill="currentColor"
+                  aria-hidden="true"
+                >
+                  <path d="m20.216 6.415-.132-.666c-.119-.598-.388-1.163-1.001-1.379-.197-.069-.42-.098-.57-.241-.152-.143-.196-.366-.231-.572-.065-.378-.125-.756-.192-1.133-.057-.325-.102-.69-.25-.987-.195-.4-.597-.634-.996-.788a5.723 5.723 0 0 0-.626-.194c-1-.263-2.05-.36-3.077-.416a25.834 25.834 0 0 0-3.7.062c-.915.083-1.88.184-2.75.5-.318.116-.646.256-.888.501-.297.302-.393.77-.177 1.146.154.267.415.456.692.58.36.162.737.284 1.123.366 1.075.238 2.189.331 3.287.37 1.218.05 2.437.01 3.65-.118.299-.033.598-.073.896-.119.352-.054.578-.513.474-.834-.124-.383-.457-.531-.834-.473-.466.074-.96.108-1.382.146-1.177.08-2.358.082-3.536.006a22.228 22.228 0 0 1-1.157-.107c-.086-.01-.18-.025-.258-.036-.243-.036-.484-.08-.724-.13-.111-.027-.111-.185 0-.212h.005c.277-.06.557-.108.838-.147h.002c.131-.009.263-.032.394-.048a25.076 25.076 0 0 1 3.426-.12c.674.019 1.347.067 2.017.144l.228.031c.267.04.533.088.798.145.392.085.895.113 1.07.542.055.137.08.288.111.431l.319 1.484a.237.237 0 0 1-.199.284h-.003c-.037.006-.075.01-.112.015a36.704 36.704 0 0 1-4.743.295 37.059 37.059 0 0 1-4.699-.304c-.14-.017-.293-.042-.417-.06-.326-.048-.649-.108-.973-.161-.393-.065-.768-.032-1.123.161-.29.16-.527.404-.675.701-.154.316-.199.66-.267 1-.069.34-.176.707-.135 1.056.087.753.613 1.365 1.37 1.502a39.69 39.69 0 0 0 11.343.376.483.483 0 0 1 .535.53l-.071.697-1.018 9.907c-.041.41-.047.832-.125 1.237-.122.637-.553 1.028-1.182 1.171-.577.131-1.165.2-1.756.205-.656.004-1.31-.025-1.966-.022-.699.004-1.556-.06-2.095-.58-.475-.458-.54-1.174-.605-1.793l-.731-7.013-.322-3.094c-.037-.351-.286-.695-.678-.678-.336.015-.718.3-.678.679l.228 2.185.949 9.112c.147 1.344 1.174 2.068 2.446 2.272.742.12 1.503.144 2.257.156.966.016 1.942.053 2.892-.122 1.408-.258 2.465-1.198 2.616-2.657.34-3.332.683-6.663 1.024-9.995l.215-2.087a.484.484 0 0 1 .39-.426c.402-.078.787-.212 1.074-.518.455-.488.546-1.124.385-1.766zm-1.478.772c-.145.137-.363.201-.578.233-2.416.359-4.866.54-7.308.46-1.748-.06-3.477-.254-5.207-.498-.17-.024-.353-.055-.47-.18-.22-.236-.111-.71-.054-.995.052-.26.152-.609.463-.646.484-.057 1.046.148 1.526.22.577.088 1.156.159 1.737.212 2.48.226 5.002.19 7.472-.14.45-.06.899-.13 1.345-.21.399-.072.84-.206 1.08.206.166.281.188.657.162.974a.544.544 0 0 1-.169.364zm-6.159 3.9c-.862.37-1.84.788-3.109.788a5.884 5.884 0 0 1-1.569-.217l.877 9.004c.065.78.717 1.38 1.5 1.38 0 0 1.243.065 1.658.065.447 0 1.786-.065 1.786-.065.783 0 1.434-.6 1.499-1.38l.94-9.95a3.996 3.996 0 0 0-1.322-.238c-.826 0-1.491.284-2.26.613z" />
+                </svg>
+                Buy me a coffee
+                <ArrowUpRight className="h-3.5 w-3.5 text-muted-foreground/40 group-hover:text-muted-foreground transition-colors" />
+              </a>
+              <a
+                href="https://github.com/jamiepine/voicebox"
+                target="_blank"
+                rel="noopener noreferrer"
+                className="group inline-flex items-center gap-2 rounded-lg border border-border/60 px-4 py-2 text-sm transition-colors hover:bg-muted/50"
+              >
+                <svg
+                  className="h-4 w-4 text-muted-foreground"
+                  viewBox="0 0 24 24"
+                  fill="currentColor"
+                  aria-hidden="true"
+                >
+                  <path d="M12 2C6.477 2 2 6.484 2 12.017c0 4.425 2.865 8.18 6.839 9.504.5.092.682-.217.682-.483 0-.237-.008-.868-.013-1.703-2.782.605-3.369-1.343-3.369-1.343-.454-1.158-1.11-1.466-1.11-1.466-.908-.62.069-.608.069-.608 1.003.07 1.531 1.032 1.531 1.032.892 1.53 2.341 1.088 2.91.832.092-.647.35-1.088.636-1.338-2.22-.253-4.555-1.113-4.555-4.951 0-1.093.39-1.988 1.029-2.688-.103-.253-.446-1.272.098-2.65 0 0 .84-.27 2.75 1.026A9.564 9.564 0 0112 6.844c.85.004 1.705.115 2.504.337 1.909-1.296 2.747-1.027 2.747-1.027.546 1.379.202 2.398.1 2.651.64.7 1.028 1.595 1.028 2.688 0 3.848-2.339 4.695-4.566 4.943.359.309.678.92.678 1.855 0 1.338-.012 2.419-.012 2.747 0 .268.18.58.688.482A10.019 10.019 0 0022 12.017C22 6.484 17.522 2 12 2z" />
+                </svg>
+                GitHub
+                <ArrowUpRight className="h-3.5 w-3.5 text-muted-foreground/40 group-hover:text-muted-foreground transition-colors" />
+              </a>
+            </div>
+          </FadeIn>
+
+          <FadeIn delay={400}>
+            <p className="text-xs text-muted-foreground/40 pt-4">
+              Licensed under{' '}
+              <a
+                href="https://github.com/jamiepine/voicebox/blob/main/LICENSE"
+                target="_blank"
+                rel="noopener noreferrer"
+                className="hover:text-muted-foreground/60 transition-colors"
+              >
+                MIT
+              </a>
+            </p>
+          </FadeIn>
+        </div>
+      </div>
+    </>
+  );
+}

app/src/components/ServerTab/ChangelogPage.tsx

@@ -0,0 +1,220 @@
+import changelogRaw from 'virtual:changelog';
+import { useMemo, useState } from 'react';
+import { Badge } from '@/components/ui/badge';
+import { type ChangelogEntry, parseChangelog } from '@/lib/utils/parseChangelog';
+
+function renderMarkdown(md: string): React.ReactNode[] {
+  const lines = md.split('\n');
+  const elements: React.ReactNode[] = [];
+  let i = 0;
+
+  while (i < lines.length) {
+    const line = lines[i];
+
+    // Skip empty lines
+    if (line.trim() === '') {
+      i++;
+      continue;
+    }
+
+    // Tables — collect all lines starting with |
+    if (line.trim().startsWith('|')) {
+      const tableLines: string[] = [];
+      while (i < lines.length && lines[i].trim().startsWith('|')) {
+        tableLines.push(lines[i]);
+        i++;
+      }
+      elements.push(renderTable(tableLines, elements.length));
+      continue;
+    }
+
+    // Headings
+    if (line.startsWith('#### ')) {
+      elements.push(
+        <h5 key={elements.length} className="text-sm font-medium mt-5 mb-1">
+          {inlineMarkdown(line.slice(5))}
+        </h5>,
+      );
+      i++;
+      continue;
+    }
+    if (line.startsWith('### ')) {
+      elements.push(
+        <h4 key={elements.length} className="text-sm font-medium mt-6 mb-2">
+          {inlineMarkdown(line.slice(4))}
+        </h4>,
+      );
+      i++;
+      continue;
+    }
+
+    // List items — collect consecutive
+    if (line.startsWith('- ')) {
+      const items: string[] = [];
+      while (i < lines.length && lines[i].startsWith('- ')) {
+        items.push(lines[i].slice(2));
+        i++;
+      }
+      elements.push(
+        <ul key={elements.length} className="space-y-1 my-2">
+          {items.map((item, idx) => (
+            <li key={idx} className="text-sm text-muted-foreground flex gap-2">
+              <span className="text-muted-foreground/50 select-none shrink-0">&bull;</span>
+              <span>{inlineMarkdown(item)}</span>
+            </li>
+          ))}
+        </ul>,
+      );
+      continue;
+    }
+
+    // Paragraph
+    elements.push(
+      <p key={elements.length} className="text-sm text-muted-foreground my-2">
+        {inlineMarkdown(line)}
+      </p>,
+    );
+    i++;
+  }
+
+  return elements;
+}
+
+function renderTable(tableLines: string[], keyBase: number): React.ReactNode {
+  const parseRow = (line: string) =>
+    line
+      .split('|')
+      .slice(1, -1)
+      .map((c) => c.trim());
+
+  const headers = parseRow(tableLines[0]);
+  // Skip separator line (index 1)
+  const rows = tableLines.slice(2).map(parseRow);
+
+  return (
+    <div key={keyBase} className="overflow-x-auto my-3">
+      <table className="text-sm w-full">
+        <thead>
+          <tr className="border-b">
+            {headers.map((h, hIdx) => (
+              <th
+                key={hIdx}
+                className="text-left py-1.5 pr-4 text-muted-foreground font-medium text-xs"
+              >
+                {inlineMarkdown(h)}
+              </th>
+            ))}
+          </tr>
+        </thead>
+        <tbody>
+          {rows.map((row, rowIdx) => (
+            <tr key={rowIdx} className="border-b border-border/50">
+              {row.map((cell, cellIdx) => (
+                <td key={cellIdx} className="py-1.5 pr-4 text-muted-foreground">
+                  {inlineMarkdown(cell)}
+                </td>
+              ))}
+            </tr>
+          ))}
+        </tbody>
+      </table>
+    </div>
+  );
+}
+
+function inlineMarkdown(text: string): React.ReactNode {
+  // Process inline markdown: bold, code, links
+  const parts: React.ReactNode[] = [];
+  // Regex matches: **bold**, `code`, [text](url)
+  const inlineRe = /\*\*(.+?)\*\*|`([^`]+)`|\[([^\]]+)\]\(([^)]+)\)/g;
+  let lastIndex = 0;
+  let match: RegExpExecArray | null = inlineRe.exec(text);
+
+  while (match !== null) {
+    if (match.index > lastIndex) {
+      parts.push(text.slice(lastIndex, match.index));
+    }
+
+    if (match[1] !== undefined) {
+      // Bold
+      parts.push(
+        <strong key={parts.length} className="font-medium text-foreground">
+          {match[1]}
+        </strong>,
+      );
+    } else if (match[2] !== undefined) {
+      // Code
+      parts.push(
+        <code key={parts.length} className="px-1 py-0.5 rounded bg-muted text-xs font-mono">
+          {match[2]}
+        </code>,
+      );
+    } else if (match[3] !== undefined && match[4] !== undefined) {
+      // Link
+      parts.push(
+        <a
+          key={parts.length}
+          href={match[4]}
+          target="_blank"
+          rel="noopener noreferrer"
+          className="text-accent hover:underline"
+        >
+          {match[3]}
+        </a>,
+      );
+    }
+
+    lastIndex = match.index + match[0].length;
+    match = inlineRe.exec(text);
+  }
+
+  if (lastIndex < text.length) {
+    parts.push(text.slice(lastIndex));
+  }
+
+  return parts.length === 1 ? parts[0] : parts;
+}
+
+function ChangelogEntryCard({ entry }: { entry: ChangelogEntry }) {
+  const [expanded, setExpanded] = useState(false);
+  const content = useMemo(() => renderMarkdown(entry.body), [entry.body]);
+  const isLong = entry.body.split('\n').length > 12;
+
+  return (
+    <div className="border-b border-border/50 pb-6">
+      <div className="flex items-baseline gap-3 mb-1">
+        <h3 className="text-sm font-medium">{entry.version}</h3>
+        {entry.date && <span className="text-xs text-muted-foreground">{entry.date}</span>}
+        {entry.version === 'Unreleased' && <Badge variant="outline">dev</Badge>}
+      </div>
+
+      <div className={isLong && !expanded ? 'max-h-48 overflow-hidden relative' : ''}>
+        {content}
+        {isLong && !expanded && (
+          <div className="absolute bottom-0 left-0 right-0 h-16 bg-gradient-to-t from-background to-transparent" />
+        )}
+      </div>
+
+      {isLong && (
+        <button
+          onClick={() => setExpanded(!expanded)}
+          className="text-xs text-accent hover:underline mt-2"
+        >
+          {expanded ? 'Show less' : 'Show more'}
+        </button>
+      )}
+    </div>
+  );
+}
+
+export function ChangelogPage() {
+  const entries = useMemo(() => parseChangelog(changelogRaw), []);
+
+  return (
+    <div className="space-y-6 max-w-2xl">
+      {entries.map((entry) => (
+        <ChangelogEntryCard key={entry.version} entry={entry} />
+      ))}
+    </div>
+  );
+}

app/src/components/ServerTab/GeneralPage.tsx

@@ -0,0 +1,379 @@
+import { zodResolver } from '@hookform/resolvers/zod';
+import { AlertCircle, ArrowUpRight, Book, Download, Loader2, RefreshCw } from 'lucide-react';
+import { useEffect, useState } from 'react';
+import { useForm } from 'react-hook-form';
+import * as z from 'zod';
+import { Button } from '@/components/ui/button';
+import { Form, FormControl, FormField, FormItem, FormMessage } from '@/components/ui/form';
+import { Input } from '@/components/ui/input';
+import { Progress } from '@/components/ui/progress';
+import { Toggle } from '@/components/ui/toggle';
+import { useToast } from '@/components/ui/use-toast';
+import { useAutoUpdater } from '@/hooks/useAutoUpdater';
+import { useServerHealth } from '@/lib/hooks/useServer';
+import { usePlatform } from '@/platform/PlatformContext';
+import { useServerStore } from '@/stores/serverStore';
+import { SettingRow, SettingSection } from './SettingRow';
+
+const connectionSchema = z.object({
+  serverUrl: z.string().url('Please enter a valid URL'),
+});
+
+type ConnectionFormValues = z.infer<typeof connectionSchema>;
+
+export function GeneralPage() {
+  const platform = usePlatform();
+  const serverUrl = useServerStore((state) => state.serverUrl);
+  const setServerUrl = useServerStore((state) => state.setServerUrl);
+  const keepServerRunningOnClose = useServerStore((state) => state.keepServerRunningOnClose);
+  const setKeepServerRunningOnClose = useServerStore((state) => state.setKeepServerRunningOnClose);
+  const mode = useServerStore((state) => state.mode);
+  const setMode = useServerStore((state) => state.setMode);
+  const { toast } = useToast();
+  const { data: health, isLoading, error: healthError } = useServerHealth();
+
+  const form = useForm<ConnectionFormValues>({
+    resolver: zodResolver(connectionSchema),
+    defaultValues: { serverUrl },
+  });
+
+  useEffect(() => {
+    form.reset({ serverUrl });
+  }, [serverUrl, form]);
+
+  const { isDirty } = form.formState;
+
+  function onSubmit(data: ConnectionFormValues) {
+    setServerUrl(data.serverUrl);
+    form.reset(data);
+    toast({
+      title: 'Server URL updated',
+      description: `Connected to ${data.serverUrl}`,
+    });
+  }
+
+  return (
+    <div className="space-y-8 max-w-2xl">
+      <div className="grid grid-cols-2 gap-3">
+        <a
+          href="https://docs.voicebox.sh"
+          target="_blank"
+          rel="noopener noreferrer"
+          className="group flex items-center gap-3 rounded-lg border border-border/60 p-4 transition-colors hover:bg-muted/50"
+        >
+          <Book className="h-5 w-5 shrink-0 text-accent" strokeWidth={2.5} />
+          <div className="min-w-0 flex-1">
+            <div className="text-sm font-medium">Read the Docs</div>
+            <div className="text-xs text-muted-foreground">docs.voicebox.sh</div>
+          </div>
+          <ArrowUpRight className="h-4 w-4 text-muted-foreground/40 group-hover:text-muted-foreground transition-colors" />
+        </a>
+        <a
+          href="https://discord.gg/StkzQasqPS"
+          target="_blank"
+          rel="noopener noreferrer"
+          className="group flex items-center gap-3 rounded-lg border border-border/60 p-4 transition-colors hover:bg-muted/50"
+        >
+          <svg
+            className="h-5 w-5 shrink-0 text-accent"
+            viewBox="0 0 24 24"
+            fill="currentColor"
+            aria-hidden="true"
+          >
+            <path d="M20.317 4.37a19.791 19.791 0 0 0-4.885-1.515.074.074 0 0 0-.079.037c-.21.375-.444.864-.608 1.25a18.27 18.27 0 0 0-5.487 0 12.64 12.64 0 0 0-.617-1.25.077.077 0 0 0-.079-.037A19.736 19.736 0 0 0 3.677 4.37a.07.07 0 0 0-.032.027C.533 9.046-.32 13.58.099 18.057a.082.082 0 0 0 .031.057 19.9 19.9 0 0 0 5.993 3.03.078.078 0 0 0 .084-.028c.462-.63.874-1.295 1.226-1.994a.076.076 0 0 0-.041-.106 13.107 13.107 0 0 1-1.872-.892.077.077 0 0 1-.008-.128 10.2 10.2 0 0 0 .372-.292.074.074 0 0 1 .077-.01c3.928 1.793 8.18 1.793 12.062 0a.074.074 0 0 1 .078.01c.12.098.246.198.373.292a.077.077 0 0 1-.006.127 12.299 12.299 0 0 1-1.873.892.077.077 0 0 0-.041.107c.36.698.772 1.362 1.225 1.993a.076.076 0 0 0 .084.028 19.839 19.839 0 0 0 6.002-3.03.077.077 0 0 0 .032-.054c.5-5.177-.838-9.674-3.549-13.66a.061.061 0 0 0-.031-.03zM8.02 15.33c-1.183 0-2.157-1.085-2.157-2.419 0-1.333.956-2.419 2.157-2.419 1.21 0 2.176 1.095 2.157 2.42 0 1.333-.956 2.418-2.157 2.418zm7.975 0c-1.183 0-2.157-1.085-2.157-2.419 0-1.333.955-2.419 2.157-2.419 1.21 0 2.176 1.095 2.157 2.42 0 1.333-.946 2.418-2.157 2.418z" />
+          </svg>
+          <div className="min-w-0 flex-1">
+            <div className="text-sm font-medium">Join the Discord</div>
+            <div className="text-xs text-muted-foreground">Get help & share voices</div>
+          </div>
+          <ArrowUpRight className="h-4 w-4 text-muted-foreground/40 group-hover:text-muted-foreground transition-colors" />
+        </a>
+      </div>
+
+      <SettingSection>
+        <SettingRow
+          title="Server URL"
+          description="The address of your voicebox backend server."
+          action={
+            <ConnectionStatus health={health} isLoading={isLoading} healthError={healthError} />
+          }
+        >
+          <Form {...form}>
+            <form onSubmit={form.handleSubmit(onSubmit)} className="flex gap-2">
+              <FormField
+                control={form.control}
+                name="serverUrl"
+                render={({ field }) => (
+                  <FormItem className="flex-1">
+                    <FormControl>
+                      <Input placeholder="http://127.0.0.1:17493" {...field} />
+                    </FormControl>
+                    <FormMessage />
+                  </FormItem>
+                )}
+              />
+              {isDirty && (
+                <Button type="submit" size="sm">
+                  Save
+                </Button>
+              )}
+            </form>
+          </Form>
+        </SettingRow>
+
+        <SettingRow
+          title="Keep server running when app closes"
+          description="The server will continue running in the background after closing the app."
+          htmlFor="keepServerRunning"
+          action={
+            <Toggle
+              id="keepServerRunning"
+              checked={keepServerRunningOnClose}
+              onCheckedChange={(checked: boolean) => {
+                setKeepServerRunningOnClose(checked);
+                platform.lifecycle.setKeepServerRunning(checked).catch((error) => {
+                  console.error('Failed to sync setting to Rust:', error);
+                  setKeepServerRunningOnClose(!checked);
+                  toast({
+                    title: 'Failed to update setting',
+                    description: 'Could not sync setting to backend.',
+                    variant: 'destructive',
+                  });
+                  return;
+                });
+                toast({
+                  title: 'Setting updated',
+                  description: checked
+                    ? 'Server will continue running when app closes'
+                    : 'Server will stop when app closes',
+                });
+              }}
+            />
+          }
+        />
+
+        {platform.metadata.isTauri && (
+          <SettingRow
+            title="Allow network access"
+            description="Makes the server accessible from other devices on your network. Restart the app after changing."
+            htmlFor="allowNetworkAccess"
+            action={
+              <Toggle
+                id="allowNetworkAccess"
+                checked={mode === 'remote'}
+                onCheckedChange={(checked: boolean) => {
+                  setMode(checked ? 'remote' : 'local');
+                  toast({
+                    title: 'Setting updated',
+                    description: checked
+                      ? 'Network access enabled. Restart the app to apply.'
+                      : 'Network access disabled. Restart the app to apply.',
+                  });
+                }}
+              />
+            }
+          />
+        )}
+      </SettingSection>
+
+      <ApiReferenceCard serverUrl={serverUrl} />
+
+      {platform.metadata.isTauri && <UpdatesSection />}
+    </div>
+  );
+}
+
+function ConnectionStatus({
+  health,
+  isLoading,
+  healthError,
+}: {
+  health: ReturnType<typeof useServerHealth>['data'];
+  isLoading: boolean;
+  healthError: ReturnType<typeof useServerHealth>['error'];
+}) {
+  if (isLoading) {
+    return (
+      <div className="flex items-center gap-2 rounded-full border border-border/60 px-3 py-1">
+        <Loader2 className="h-3 w-3 animate-spin text-muted-foreground" />
+        <span className="text-xs text-muted-foreground">Connecting</span>
+      </div>
+    );
+  }
+  if (healthError) {
+    return (
+      <div className="flex items-center gap-2 rounded-full border border-destructive/30 px-3 py-1">
+        <span className="relative flex h-2 w-2">
+          <span className="absolute inline-flex h-full w-full rounded-full bg-destructive/40" />
+          <span className="relative inline-flex h-2 w-2 rounded-full bg-destructive" />
+        </span>
+        <span className="text-xs text-destructive">Offline</span>
+      </div>
+    );
+  }
+  if (health) {
+    return (
+      <div className="flex items-center gap-2 rounded-full border border-accent/30 px-3 py-1">
+        <span className="relative flex h-2 w-2">
+          <span className="absolute inline-flex h-full w-full animate-ping rounded-full bg-accent/60" />
+          <span className="relative inline-flex h-2 w-2 rounded-full bg-accent shadow-[0_0_6px_1px_hsl(var(--accent)/0.5)]" />
+        </span>
+        <span className="text-xs text-muted-foreground">Online</span>
+      </div>
+    );
+  }
+  return null;
+}
+
+function UpdatesSection() {
+  const platform = usePlatform();
+  const { status, checkForUpdates, downloadAndInstall, restartAndInstall } = useAutoUpdater(false);
+  const [currentVersion, setCurrentVersion] = useState<string>('');
+  const isDev = !import.meta.env?.PROD;
+
+  useEffect(() => {
+    platform.metadata
+      .getVersion()
+      .then(setCurrentVersion)
+      .catch(() => setCurrentVersion('Unknown'));
+  }, [platform]);
+
+  return (
+    <SettingSection title="App Updates" description={`v${currentVersion}${isDev ? ' (dev)' : ''}`}>
+      {isDev ? (
+        <SettingRow
+          title="Development mode"
+          description="Auto-updates are disabled in development mode."
+        />
+      ) : (
+        <>
+          <SettingRow
+            title="Check for updates"
+            description={
+              status.available
+                ? `Version ${status.version} available`
+                : status.checking
+                  ? 'Checking...'
+                  : "You're up to date"
+            }
+            action={
+              <Button
+                onClick={checkForUpdates}
+                disabled={status.checking || status.downloading || status.readyToInstall}
+                variant="outline"
+                size="sm"
+              >
+                <RefreshCw
+                  className={`h-3.5 w-3.5 mr-1.5 ${status.checking ? 'animate-spin' : ''}`}
+                />
+                Check
+              </Button>
+            }
+          />
+
+          {status.error && (
+            <SettingRow title="Update error">
+              <div className="flex items-center gap-2 text-sm text-destructive">
+                <AlertCircle className="h-4 w-4" />
+                {status.error}
+              </div>
+            </SettingRow>
+          )}
+
+          {status.available && !status.downloading && !status.readyToInstall && (
+            <SettingRow
+              title={`Update to ${status.version}`}
+              description="Download and install the latest version."
+              action={
+                <Button onClick={downloadAndInstall} size="sm">
+                  <Download className="h-3.5 w-3.5 mr-1.5" />
+                  Download
+                </Button>
+              }
+            />
+          )}
+
+          {status.downloading && (
+            <SettingRow title="Downloading update...">
+              <div className="space-y-1.5">
+                <Progress value={status.downloadProgress} />
+                <div className="flex items-center justify-between text-xs text-muted-foreground">
+                  {status.downloadedBytes !== undefined &&
+                  status.totalBytes !== undefined &&
+                  status.totalBytes > 0 ? (
+                    <span>
+                      {(status.downloadedBytes / 1024 / 1024).toFixed(1)} MB /{' '}
+                      {(status.totalBytes / 1024 / 1024).toFixed(1)} MB
+                    </span>
+                  ) : (
+                    <span />
+                  )}
+                  {status.downloadProgress !== undefined && <span>{status.downloadProgress}%</span>}
+                </div>
+              </div>
+            </SettingRow>
+          )}
+
+          {status.readyToInstall && (
+            <SettingRow
+              title="Update ready to install"
+              description={`Version ${status.version} has been downloaded. Restart to complete.`}
+              action={
+                <Button onClick={restartAndInstall} size="sm">
+                  <RefreshCw className="h-3.5 w-3.5 mr-1.5" />
+                  Restart Now
+                </Button>
+              }
+            />
+          )}
+        </>
+      )}
+    </SettingSection>
+  );
+}
+
+const API_ENDPOINTS = [
+  { method: 'POST', path: '/generate', label: 'Generate speech' },
+  { method: 'GET', path: '/health', label: 'Server status' },
+  { method: 'GET', path: '/profiles', label: 'List voices' },
+  { method: 'GET', path: '/history', label: 'Past generations' },
+];
+
+function ApiReferenceCard({ serverUrl }: { serverUrl: string }) {
+  return (
+    <div className="rounded-lg border border-border/60 p-4 space-y-3">
+      <div>
+        <h3 className="text-sm font-medium">API Access</h3>
+        <p className="text-sm text-muted-foreground">
+          Integrate Voicebox into your workflow via the REST API at{' '}
+          <code className="text-xs bg-muted px-1 py-0.5 rounded font-mono">{serverUrl}</code>
+        </p>
+      </div>
+      <div className="space-y-1">
+        {API_ENDPOINTS.map((ep) => (
+          <div key={ep.path} className="flex items-center gap-2.5 py-1">
+            <span
+              className={`text-[10px] font-mono font-semibold w-9 text-center rounded px-1 py-px ${
+                ep.method === 'POST' ? 'bg-accent/10 text-accent' : 'bg-muted text-muted-foreground'
+              }`}
+            >
+              {ep.method}
+            </span>
+            <code className="text-xs font-mono text-muted-foreground">{ep.path}</code>
+            <span className="text-xs text-muted-foreground/50 ml-auto">{ep.label}</span>
+          </div>
+        ))}
+      </div>
+      <p className="text-xs text-muted-foreground">
+        <a
+          href={`${serverUrl}/docs`}
+          target="_blank"
+          rel="noopener noreferrer"
+          className="text-accent hover:underline"
+        >
+          View the full API reference
+        </a>
+      </p>
+    </div>
+  );
+}

app/src/components/ServerTab/GenerationPage.tsx

@@ -0,0 +1,138 @@
+import { FolderOpen } from 'lucide-react';
+import { useCallback, useEffect, useState } from 'react';
+import { Button } from '@/components/ui/button';
+import { Slider } from '@/components/ui/slider';
+import { Toggle } from '@/components/ui/toggle';
+import { usePlatform } from '@/platform/PlatformContext';
+import { useServerStore } from '@/stores/serverStore';
+import { SettingRow, SettingSection } from './SettingRow';
+
+export function GenerationPage() {
+  const platform = usePlatform();
+  const serverUrl = useServerStore((state) => state.serverUrl);
+  const maxChunkChars = useServerStore((state) => state.maxChunkChars);
+  const setMaxChunkChars = useServerStore((state) => state.setMaxChunkChars);
+  const crossfadeMs = useServerStore((state) => state.crossfadeMs);
+  const setCrossfadeMs = useServerStore((state) => state.setCrossfadeMs);
+  const normalizeAudio = useServerStore((state) => state.normalizeAudio);
+  const setNormalizeAudio = useServerStore((state) => state.setNormalizeAudio);
+  const autoplayOnGenerate = useServerStore((state) => state.autoplayOnGenerate);
+  const setAutoplayOnGenerate = useServerStore((state) => state.setAutoplayOnGenerate);
+  const [opening, setOpening] = useState(false);
+  const [generationsPath, setGenerationsPath] = useState<string | null>(null);
+
+  useEffect(() => {
+    fetch(`${serverUrl}/health/filesystem`)
+      .then((res) => res.json())
+      .then((data) => {
+        const genDir = data.directories?.find((d: { path: string }) =>
+          d.path.includes('generations'),
+        );
+        if (genDir?.path) setGenerationsPath(genDir.path);
+      })
+      .catch(() => {});
+  }, [serverUrl]);
+
+  const openGenerationsFolder = useCallback(async () => {
+    if (!generationsPath) return;
+    setOpening(true);
+    try {
+      await platform.filesystem.openPath(generationsPath);
+    } catch (e) {
+      console.error('Failed to open generations folder:', e);
+    } finally {
+      setOpening(false);
+    }
+  }, [platform, generationsPath]);
+
+  return (
+    <div className="space-y-8 max-w-2xl">
+      <SettingSection
+        title="Generation"
+        description="Controls for long text generation. These settings apply to all engines."
+      >
+        <SettingRow
+          title="Auto-chunking limit"
+          description="Long text is split into chunks at sentence boundaries. Lower values can improve quality for long outputs."
+          action={
+            <span className="text-sm tabular-nums text-muted-foreground">
+              {maxChunkChars} chars
+            </span>
+          }
+        >
+          <Slider
+            id="maxChunkChars"
+            value={[maxChunkChars]}
+            onValueChange={([value]) => setMaxChunkChars(value)}
+            min={100}
+            max={5000}
+            step={50}
+            aria-label="Auto-chunking character limit"
+          />
+        </SettingRow>
+
+        <SettingRow
+          title="Chunk crossfade"
+          description="Blends audio between chunks to smooth transitions. Set to 0 for a hard cut."
+          action={
+            <span className="text-sm tabular-nums text-muted-foreground">
+              {crossfadeMs === 0 ? 'Cut' : `${crossfadeMs}ms`}
+            </span>
+          }
+        >
+          <Slider
+            id="crossfadeMs"
+            value={[crossfadeMs]}
+            onValueChange={([value]) => setCrossfadeMs(value)}
+            min={0}
+            max={200}
+            step={10}
+            aria-label="Chunk crossfade duration"
+          />
+        </SettingRow>
+
+        <SettingRow
+          title="Normalize audio"
+          description="Adjusts output volume to a consistent level across generations."
+          htmlFor="normalizeAudio"
+          action={
+            <Toggle
+              id="normalizeAudio"
+              checked={normalizeAudio}
+              onCheckedChange={setNormalizeAudio}
+            />
+          }
+        />
+
+        <SettingRow
+          title="Autoplay on generate"
+          description="Automatically play audio when a generation completes."
+          htmlFor="autoplayOnGenerate"
+          action={
+            <Toggle
+              id="autoplayOnGenerate"
+              checked={autoplayOnGenerate}
+              onCheckedChange={setAutoplayOnGenerate}
+            />
+          }
+        />
+
+        <SettingRow
+          title="Generations folder"
+          description={generationsPath ?? 'Where generated audio files are stored on disk.'}
+          action={
+            <Button
+              variant="outline"
+              size="sm"
+              onClick={openGenerationsFolder}
+              disabled={opening || !generationsPath}
+            >
+              <FolderOpen className="h-3.5 w-3.5 mr-1.5" />
+              Open
+            </Button>
+          }
+        />
+      </SettingSection>
+    </div>
+  );
+}

app/src/components/ServerTab/GpuPage.tsx

@@ -0,0 +1,405 @@
+import { useQuery, useQueryClient } from '@tanstack/react-query';
+import { AlertCircle, Cpu, Download, Loader2, RotateCw, Trash2 } from 'lucide-react';
+import { useCallback, useEffect, useRef, useState } from 'react';
+import { Button } from '@/components/ui/button';
+import { Progress } from '@/components/ui/progress';
+import { apiClient } from '@/lib/api/client';
+import type { CudaDownloadProgress, HealthResponse } from '@/lib/api/types';
+import { useServerHealth } from '@/lib/hooks/useServer';
+import { usePlatform } from '@/platform/PlatformContext';
+import { useServerStore } from '@/stores/serverStore';
+import { SettingRow, SettingSection } from './SettingRow';
+
+type RestartPhase = 'idle' | 'stopping' | 'waiting' | 'ready';
+
+function AppleLogo({ className }: { className?: string }) {
+  return (
+    <svg className={className} viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
+      <path d="M18.71 19.5c-.83 1.24-1.71 2.45-3.05 2.47-1.34.03-1.77-.79-3.29-.79-1.53 0-2 .77-3.27.82-1.31.05-2.3-1.32-3.14-2.53C4.25 17 2.94 12.45 4.7 9.39c.87-1.52 2.43-2.48 4.12-2.51 1.28-.02 2.5.87 3.29.87.78 0 2.26-1.07 3.8-.91.65.03 2.47.26 3.64 1.98-.09.06-2.17 1.28-2.15 3.81.03 3.02 2.65 4.03 2.68 4.04-.03.07-.42 1.44-1.38 2.83M13 3.5c.73-.83 1.94-1.46 2.94-1.5.13 1.17-.34 2.35-1.04 3.19-.69.85-1.83 1.51-2.95 1.42-.15-1.15.41-2.35 1.05-3.11z" />
+    </svg>
+  );
+}
+
+function GpuIcon({ className }: { className?: string }) {
+  return (
+    <svg
+      className={className}
+      viewBox="0 0 24 24"
+      fill="none"
+      stroke="currentColor"
+      strokeWidth="1.5"
+      strokeLinecap="round"
+      strokeLinejoin="round"
+      aria-hidden="true"
+    >
+      <rect x="4" y="6" width="16" height="12" rx="2" />
+      <path d="M2 10h2M2 14h2M20 10h2M20 14h2" />
+      <path d="M9 10h6M9 14h4" />
+    </svg>
+  );
+}
+
+function GpuInfoCard({ health }: { health: HealthResponse }) {
+  const hasGpu = health.gpu_available && health.gpu_type;
+
+  // Parse GPU name from type string like "CUDA (NVIDIA RTX 4090)" or "MPS (Apple M2 Pro)"
+  const gpuName = hasGpu
+    ? health.gpu_type!.replace(/^(CUDA|ROCm|MPS|Metal|XPU|DirectML)\s*\((.+)\)$/, '$2') ||
+      health.gpu_type!
+    : null;
+  const gpuBackend = hasGpu ? health.gpu_type!.replace(/\s*\(.+\)$/, '') : null;
+  const isApple = gpuBackend === 'MPS' || gpuBackend === 'Metal';
+  const showBackendVariant = health.backend_variant && health.backend_variant !== 'cpu';
+
+  return (
+    <div className="rounded-lg border border-border/60 p-4">
+      <div className="flex items-center gap-3">
+        {hasGpu ? (
+          isApple ? (
+            <AppleLogo className="h-5 w-5 shrink-0 text-muted-foreground" />
+          ) : (
+            <GpuIcon className="h-5 w-5 shrink-0 text-accent" />
+          )
+        ) : (
+          <Cpu className="h-5 w-5 shrink-0 text-muted-foreground" />
+        )}
+        <div className="flex-1 min-w-0 space-y-0.5">
+          <div className="text-sm font-medium">{hasGpu ? gpuName : 'CPU Only'}</div>
+          <div className="flex flex-wrap items-center gap-x-3 gap-y-1 text-xs text-muted-foreground">
+            {hasGpu ? (
+              <>
+                <span>{gpuBackend}</span>
+                {showBackendVariant && (
+                  <>
+                    <span className="text-border">|</span>
+                    <span className="uppercase">{health.backend_variant}</span>
+                  </>
+                )}
+                {health.vram_used_mb != null && health.vram_used_mb > 0 && (
+                  <>
+                    <span className="text-border">|</span>
+                    <span>{health.vram_used_mb.toFixed(0)} MB VRAM</span>
+                  </>
+                )}
+              </>
+            ) : (
+              <span>No GPU acceleration detected</span>
+            )}
+          </div>
+        </div>
+        {hasGpu && (
+          <div className="flex items-center gap-2 rounded-full border border-accent/30 px-2.5 py-0.5">
+            <span className="relative flex h-1.5 w-1.5">
+              <span className="absolute inline-flex h-full w-full animate-ping rounded-full bg-accent/60" />
+              <span className="relative inline-flex h-1.5 w-1.5 rounded-full bg-accent shadow-[0_0_4px_1px_hsl(var(--accent)/0.4)]" />
+            </span>
+            <span className="text-[10px] font-medium text-muted-foreground">Active</span>
+          </div>
+        )}
+      </div>
+    </div>
+  );
+}
+
+export function GpuPage() {
+  const platform = usePlatform();
+  const queryClient = useQueryClient();
+  const serverUrl = useServerStore((state) => state.serverUrl);
+  const { data: health } = useServerHealth();
+
+  const [restartPhase, setRestartPhase] = useState<RestartPhase>('idle');
+  const [error, setError] = useState<string | null>(null);
+  const [downloadProgress, setDownloadProgress] = useState<CudaDownloadProgress | null>(null);
+  const healthPollRef = useRef<ReturnType<typeof setInterval> | null>(null);
+
+  const {
+    data: cudaStatus,
+    isLoading: _cudaStatusLoading,
+    refetch: refetchCudaStatus,
+  } = useQuery({
+    queryKey: ['cuda-status', serverUrl],
+    queryFn: () => apiClient.getCudaStatus(),
+    refetchInterval: (query) => (query.state.status === 'pending' ? false : 10000),
+    retry: 1,
+    enabled: !!health,
+  });
+
+  const isCurrentlyCuda = health?.backend_variant === 'cuda';
+  const cudaAvailable = cudaStatus?.available ?? false;
+  const cudaDownloading = cudaStatus?.downloading ?? false;
+
+  useEffect(() => {
+    return () => {
+      if (healthPollRef.current) {
+        clearInterval(healthPollRef.current);
+        healthPollRef.current = null;
+      }
+    };
+  }, []);
+
+  useEffect(() => {
+    if (!cudaDownloading || !serverUrl) return;
+
+    const eventSource = new EventSource(`${serverUrl}/backend/cuda-progress`);
+
+    eventSource.onmessage = (event) => {
+      try {
+        const data = JSON.parse(event.data) as CudaDownloadProgress;
+        setDownloadProgress(data);
+
+        if (data.status === 'complete') {
+          eventSource.close();
+          setDownloadProgress(null);
+          refetchCudaStatus();
+        } else if (data.status === 'error') {
+          eventSource.close();
+          setError(data.error || 'Download failed');
+          setDownloadProgress(null);
+          refetchCudaStatus();
+        }
+      } catch (e) {
+        console.error('Error parsing CUDA progress event:', e);
+      }
+    };
+
+    eventSource.onerror = () => {
+      eventSource.close();
+    };
+
+    return () => {
+      eventSource.close();
+    };
+  }, [cudaDownloading, serverUrl, refetchCudaStatus]);
+
+  const clearHealthPolling = useCallback(() => {
+    if (healthPollRef.current) {
+      clearInterval(healthPollRef.current);
+      healthPollRef.current = null;
+    }
+  }, []);
+
+  const startHealthPolling = useCallback(() => {
+    clearHealthPolling();
+
+    healthPollRef.current = setInterval(async () => {
+      try {
+        const result = await apiClient.getHealth();
+        if (result.status === 'healthy') {
+          clearHealthPolling();
+          setRestartPhase('ready');
+          queryClient.invalidateQueries();
+          setTimeout(() => setRestartPhase('idle'), 2000);
+        }
+      } catch {
+        // Server still down, keep polling
+      }
+    }, 1000);
+  }, [queryClient, clearHealthPolling]);
+
+  const restartServerWithPolling = useCallback(
+    async (errorMessage: string) => {
+      setRestartPhase('stopping');
+      try {
+        await platform.lifecycle.restartServer();
+        setRestartPhase('waiting');
+        startHealthPolling();
+      } catch (e: unknown) {
+        clearHealthPolling();
+        setRestartPhase('idle');
+        throw new Error(e instanceof Error ? e.message : errorMessage);
+      }
+    },
+    [platform, startHealthPolling, clearHealthPolling],
+  );
+
+  const handleDownload = async () => {
+    setError(null);
+    try {
+      await apiClient.downloadCudaBackend();
+      refetchCudaStatus();
+    } catch (e: unknown) {
+      const msg = e instanceof Error ? e.message : 'Failed to start download';
+      if (msg.includes('already downloaded')) {
+        refetchCudaStatus();
+      } else {
+        setError(msg);
+      }
+    }
+  };
+
+  const handleRestart = async () => {
+    setError(null);
+    try {
+      await restartServerWithPolling('Restart failed');
+    } catch (e: unknown) {
+      setError(e instanceof Error ? e.message : 'Restart failed');
+    }
+  };
+
+  const handleSwitchToCpu = async () => {
+    setError(null);
+    setRestartPhase('stopping');
+    try {
+      await apiClient.deleteCudaBackend();
+      await restartServerWithPolling('Failed to switch to CPU');
+    } catch (e: unknown) {
+      setError(e instanceof Error ? e.message : 'Failed to switch to CPU');
+      refetchCudaStatus();
+    }
+  };
+
+  const handleDelete = async () => {
+    setError(null);
+    try {
+      await apiClient.deleteCudaBackend();
+      refetchCudaStatus();
+    } catch (e: unknown) {
+      setError(e instanceof Error ? e.message : 'Failed to delete CUDA backend');
+    }
+  };
+
+  const formatBytes = (bytes: number): string => {
+    if (bytes === 0) return '0 B';
+    const k = 1024;
+    const sizes = ['B', 'KB', 'MB', 'GB'];
+    const i = Math.floor(Math.log(bytes) / Math.log(k));
+    return `${(bytes / k ** i).toFixed(1)} ${sizes[i]}`;
+  };
+
+  if (!health) return null;
+
+  const hasNativeGpu =
+    health.gpu_available &&
+    !isCurrentlyCuda &&
+    health.gpu_type &&
+    !health.gpu_type.includes('CUDA');
+
+  return (
+    <div className="space-y-8 max-w-2xl">
+      <GpuInfoCard health={health} />
+
+      {/* CUDA section — only when no native GPU and not already on CUDA */}
+      {!hasNativeGpu && !isCurrentlyCuda && (
+        <SettingSection
+          title="CUDA Backend"
+          description="NVIDIA GPU acceleration via a downloadable CUDA backend."
+        >
+          {/* Download progress */}
+          {cudaDownloading && downloadProgress && (
+            <SettingRow title="Downloading CUDA backend...">
+              <div className="space-y-1.5">
+                <Progress value={downloadProgress.progress} className="h-2" />
+                <div className="flex items-center justify-between text-xs text-muted-foreground">
+                  <span>
+                    {downloadProgress.filename ||
+                      (cudaAvailable ? 'Updating...' : 'Downloading...')}
+                  </span>
+                  <span>
+                    {downloadProgress.total > 0
+                      ? `${formatBytes(downloadProgress.current)} / ${formatBytes(downloadProgress.total)}`
+                      : `${downloadProgress.progress.toFixed(1)}%`}
+                  </span>
+                </div>
+              </div>
+            </SettingRow>
+          )}
+
+          {/* Restart in progress */}
+          {restartPhase !== 'idle' && (
+            <SettingRow
+              title={
+                restartPhase === 'ready'
+                  ? 'Server restarted successfully'
+                  : restartPhase === 'waiting'
+                    ? 'Restarting server...'
+                    : 'Stopping server...'
+              }
+              action={<Loader2 className="h-4 w-4 animate-spin text-muted-foreground" />}
+            />
+          )}
+
+          {/* Error */}
+          {error && (
+            <SettingRow title="Error">
+              <div className="flex items-center gap-2 text-sm text-destructive">
+                <AlertCircle className="h-4 w-4 shrink-0" />
+                <span>{error}</span>
+              </div>
+            </SettingRow>
+          )}
+
+          {/* Actions */}
+          {restartPhase === 'idle' && !cudaDownloading && (
+            <>
+              {!cudaAvailable && !isCurrentlyCuda && (
+                <SettingRow
+                  title="Download CUDA backend"
+                  description="~2.4 GB download. Requires an NVIDIA GPU with CUDA support."
+                  action={
+                    <Button onClick={handleDownload} size="sm">
+                      <Download className="h-3.5 w-3.5 mr-1.5" />
+                      Download
+                    </Button>
+                  }
+                />
+              )}
+
+              {cudaAvailable && !isCurrentlyCuda && platform.metadata.isTauri && (
+                <SettingRow
+                  title="Switch to CUDA backend"
+                  description="CUDA backend is downloaded and ready. Restart to enable."
+                  action={
+                    <Button onClick={handleRestart} size="sm">
+                      <RotateCw className="h-3.5 w-3.5 mr-1.5" />
+                      Restart
+                    </Button>
+                  }
+                />
+              )}
+
+              {isCurrentlyCuda && platform.metadata.isTauri && (
+                <SettingRow
+                  title="Switch to CPU backend"
+                  description="Disable GPU acceleration. You can re-download CUDA later."
+                  action={
+                    <Button onClick={handleSwitchToCpu} variant="outline" size="sm">
+                      <RotateCw className="h-3.5 w-3.5 mr-1.5" />
+                      Switch
+                    </Button>
+                  }
+                />
+              )}
+
+              {cudaAvailable && !isCurrentlyCuda && (
+                <SettingRow
+                  title="Remove CUDA backend"
+                  description="Delete the downloaded CUDA binary to free disk space."
+                  action={
+                    <Button
+                      onClick={handleDelete}
+                      variant="ghost"
+                      size="sm"
+                      className="text-muted-foreground hover:text-destructive"
+                    >
+                      <Trash2 className="h-3.5 w-3.5 mr-1.5" />
+                      Remove
+                    </Button>
+                  }
+                />
+              )}
+            </>
+          )}
+        </SettingSection>
+      )}
+
+      <p className="text-xs text-muted-foreground/60 leading-relaxed">
+        Voicebox automatically detects and uses the best available GPU on your system. On Apple
+        Silicon Macs, the MLX backend runs natively on the Neural Engine and GPU via Metal
+        Performance Shaders (MPS), with no additional setup required. On Windows and Linux with
+        NVIDIA GPUs, you can download an optional CUDA backend for hardware-accelerated inference.
+        AMD ROCm, Intel XPU, and DirectML are also supported where available through PyTorch. When
+        no GPU is detected, Voicebox falls back to CPU — all engines still work, just slower.
+      </p>
+    </div>
+  );
+}

app/src/components/ServerTab/LogsPage.tsx

@@ -0,0 +1,104 @@
+import { useEffect, useRef, useState } from 'react';
+import { Button } from '@/components/ui/button';
+import { cn } from '@/lib/utils/cn';
+import { type LogEntry, useLogStore } from '@/stores/logStore';
+
+function formatTime(timestamp: number): string {
+  const d = new Date(timestamp);
+  return d.toLocaleTimeString(undefined, {
+    hour: '2-digit',
+    minute: '2-digit',
+    second: '2-digit',
+    hour12: false,
+  });
+}
+
+function LogLine({ entry }: { entry: LogEntry }) {
+  return (
+    <div className="flex gap-3 font-mono text-xs leading-5 hover:bg-muted/30">
+      <span className="text-muted-foreground/50 select-none shrink-0">
+        {formatTime(entry.timestamp)}
+      </span>
+      <span
+        className={cn(
+          'whitespace-pre-wrap break-all',
+          entry.stream === 'stderr' ? 'text-orange-400/80' : 'text-muted-foreground',
+        )}
+      >
+        {entry.line}
+      </span>
+    </div>
+  );
+}
+
+export function LogsPage() {
+  const entries = useLogStore((s) => s.entries);
+  const clear = useLogStore((s) => s.clear);
+  const containerRef = useRef<HTMLDivElement>(null);
+  const [autoScroll, setAutoScroll] = useState(true);
+
+  // Auto-scroll to bottom when new entries arrive
+  useEffect(() => {
+    if (autoScroll && containerRef.current) {
+      containerRef.current.scrollTop = containerRef.current.scrollHeight;
+    }
+  }, [entries.length, autoScroll]);
+
+  // Detect manual scroll to disable auto-scroll
+  const handleScroll = () => {
+    const el = containerRef.current;
+    if (!el) return;
+    const atBottom = el.scrollHeight - el.scrollTop - el.clientHeight < 40;
+    setAutoScroll(atBottom);
+  };
+
+  return (
+    <div className="flex flex-col h-full min-h-0">
+      <div className="flex items-center justify-between mb-3">
+        <div>
+          <h3 className="text-sm font-medium">Server Logs</h3>
+          <p className="text-sm text-muted-foreground">
+            {entries.length} {entries.length === 1 ? 'line' : 'lines'}
+          </p>
+        </div>
+        <div className="flex items-center gap-2">
+          {!autoScroll && (
+            <Button
+              variant="outline"
+              size="sm"
+              onClick={() => {
+                setAutoScroll(true);
+                containerRef.current?.scrollTo({ top: containerRef.current.scrollHeight });
+              }}
+            >
+              Scroll to bottom
+            </Button>
+          )}
+          <Button variant="outline" size="sm" onClick={clear}>
+            Clear
+          </Button>
+        </div>
+      </div>
+
+      <div
+        ref={containerRef}
+        onScroll={handleScroll}
+        className="flex-1 min-h-0 overflow-y-auto rounded-md border bg-black/20 p-3"
+      >
+        {entries.length === 0 ? (
+          <div className="text-sm text-muted-foreground/50 font-mono space-y-1">
+            <p>No log output yet.</p>
+            {!import.meta.env?.PROD && (
+              <p>
+                Server logs are only captured when the app manages the server process (production
+                builds).
+              </p>
+            )}
+          </div>
+        ) : (
+          entries.map((entry) => <LogLine key={entry.id} entry={entry} />)
+        )}
+      </div>
+    </div>
+  );
+}

app/src/components/ServerTab/ServerTab.tsx

@@ -1,35 +1,70 @@
-import { ConnectionForm } from '@/components/ServerSettings/ConnectionForm';
+import { Link, Outlet, useMatchRoute } from '@tanstack/react-router';
-import { GenerationSettings } from '@/components/ServerSettings/GenerationSettings';
-import { GpuAcceleration } from '@/components/ServerSettings/GpuAcceleration';
-import { UpdateStatus } from '@/components/ServerSettings/UpdateStatus';
 import { BOTTOM_SAFE_AREA_PADDING } from '@/lib/constants/ui';
 import { cn } from '@/lib/utils/cn';
 import { usePlatform } from '@/platform/PlatformContext';
 import { usePlayerStore } from '@/stores/playerStore';
 
-export function ServerTab() {
+interface SettingsTab {
+  label: string;
+  path:
+    | '/settings'
+    | '/settings/generation'
+    | '/settings/gpu'
+    | '/settings/logs'
+    | '/settings/changelog'
+    | '/settings/about';
+  tauriOnly?: boolean;
+}
+
+const tabs: SettingsTab[] = [
+  { label: 'General', path: '/settings' },
+  { label: 'Generation', path: '/settings/generation' },
+  { label: 'GPU', path: '/settings/gpu', tauriOnly: true },
+  { label: 'Logs', path: '/settings/logs', tauriOnly: true },
+  { label: 'Changelog', path: '/settings/changelog' },
+  { label: 'About', path: '/settings/about' },
+];
+
+export function SettingsLayout() {
   const platform = usePlatform();
   const isPlayerVisible = !!usePlayerStore((state) => state.audioUrl);
+  const matchRoute = useMatchRoute();
+
   return (
-    <div
+    <div className="flex flex-col h-full min-h-0">
-      className={cn('overflow-y-auto flex flex-col', isPlayerVisible && BOTTOM_SAFE_AREA_PADDING)}
+      <nav className="flex gap-1 border-b shrink-0">
-    >
+        {tabs.map((tab) => {
-      <div className="grid gap-4 md:grid-cols-2">
+          if (tab.tauriOnly && !platform.metadata.isTauri) return null;
-        <ConnectionForm />
+
-        <GenerationSettings />
+          const isActive =
-        {platform.metadata.isTauri && <GpuAcceleration />}
+            tab.path === '/settings'
-        {platform.metadata.isTauri && <UpdateStatus />}
+              ? matchRoute({ to: tab.path, fuzzy: false })
-      </div>
+              : matchRoute({ to: tab.path });
-      <div className="py-8 text-center text-sm text-muted-foreground">
+
-        Created by{' '}
+          return (
-        <a
+            <Link
-          href="https://github.com/jamiepine"
+              key={tab.path}
-          target="_blank"
+              to={tab.path}
-          rel="noopener noreferrer"
+              className={cn(
-          className="text-accent hover:underline"
+                'px-4 py-2 text-sm font-medium transition-colors border-b-2 -mb-px',
-        >
+                isActive
-          Jamie Pine
+                  ? 'border-accent text-foreground'
-        </a>
+                  : 'border-transparent text-muted-foreground hover:text-foreground hover:border-muted-foreground/30',
+              )}
+            >
+              {tab.label}
+            </Link>
+          );
+        })}
+      </nav>
+
+      <div
+        className={cn(
+          'flex-1 overflow-y-auto pt-6 pb-6 px-2 -mx-2',
+          isPlayerVisible && BOTTOM_SAFE_AREA_PADDING,
+        )}
+      >
+        <Outlet />
       </div>
     </div>
   );

app/src/components/ServerTab/SettingRow.tsx

@@ -0,0 +1,62 @@
+import type { ReactNode } from 'react';
+
+/**
+ * A section header with title and optional description, separated by a border.
+ */
+export function SettingSection({
+  title,
+  description,
+  children,
+}: {
+  title?: string;
+  description?: string;
+  children: ReactNode;
+}) {
+  return (
+    <div className="space-y-1">
+      {title && <h3 className="text-sm font-medium">{title}</h3>}
+      {description && <p className="text-sm text-muted-foreground">{description}</p>}
+      <div className={`${title || description ? 'pt-3' : ''} space-y-0 divide-y divide-border/60`}>
+        {children}
+      </div>
+    </div>
+  );
+}
+
+/**
+ * A single settings row: label+description on the left, action on the right.
+ * Use for toggles, inputs, buttons, badges — any control type.
+ */
+export function SettingRow({
+  title,
+  description,
+  htmlFor,
+  action,
+  children,
+}: {
+  title: string;
+  description?: string;
+  htmlFor?: string;
+  /** Right-aligned control (checkbox, button, badge, etc.) */
+  action?: ReactNode;
+  /** Full-width content rendered below the label row (for sliders, inputs, etc.) */
+  children?: ReactNode;
+}) {
+  return (
+    <div className="py-3">
+      <div className="flex items-center justify-between gap-8">
+        <div className="min-w-0">
+          <label
+            htmlFor={htmlFor}
+            className={`text-sm font-medium leading-none select-none ${htmlFor ? 'cursor-pointer' : ''}`}
+          >
+            {title}
+          </label>
+          {description && <p className="text-sm text-muted-foreground mt-0.5">{description}</p>}
+        </div>
+        {action && <div className="shrink-0">{action}</div>}
+      </div>
+      {children && <div className="mt-3">{children}</div>}
+    </div>
+  );
+}

app/src/components/Sidebar.tsx

@@ -1,7 +1,10 @@
 import { Link, useMatchRoute } from '@tanstack/react-router';
-import { AudioLines, Box, Mic, Server, Speaker, Volume2, Wand2 } from 'lucide-react';
+import { AudioLines, Box, Mic, Settings, Speaker, Volume2, Wand2 } from 'lucide-react';
+import { useEffect, useState } from 'react';
 import voiceboxLogo from '@/assets/voicebox-logo.png';
 import { cn } from '@/lib/utils/cn';
+import { usePlatform } from '@/platform/PlatformContext';
+import type { UpdateStatus } from '@/platform/types';
 import { usePlayerStore } from '@/stores/playerStore';
 import { version } from '../../package.json';
 
@@ -16,12 +19,16 @@ const tabs = [
   { id: 'effects', path: '/effects', icon: Wand2, label: 'Effects' },
   { id: 'audio', path: '/audio', icon: Speaker, label: 'Audio' },
   { id: 'models', path: '/models', icon: Box, label: 'Models' },
-  { id: 'server', path: '/server', icon: Server, label: 'Server' },
+  { id: 'settings', path: '/settings', icon: Settings, label: 'Settings' },
 ];
 
 export function Sidebar({ isMacOS }: SidebarProps) {
   const matchRoute = useMatchRoute();
   const isPlayerOpen = !!usePlayerStore((s) => s.audioUrl);
+  const platform = usePlatform();
+
+  const [updateStatus, setUpdateStatus] = useState<UpdateStatus>(platform.updater.getStatus());
+  useEffect(() => platform.updater.subscribe(setUpdateStatus), [platform.updater]);
 
   return (
     <div
@@ -47,9 +54,10 @@ export function Sidebar({ isMacOS }: SidebarProps) {
       <div className="flex flex-col gap-3">
         {tabs.map((tab, index) => {
           const Icon = tab.icon;
-          // For index route, use exact match; for others, use default matching
           const isActive =
-            tab.path === '/' ? matchRoute({ to: '/', exact: true }) : matchRoute({ to: tab.path });
+            tab.path === '/'
+              ? matchRoute({ to: '/', fuzzy: false })
+              : matchRoute({ to: tab.path, fuzzy: true });
 
           // Accent fades as buttons get further from the logo
           const accentOpacity = Math.max(0.08, 0.5 - index * 0.07);
@@ -85,10 +93,18 @@ export function Sidebar({ isMacOS }: SidebarProps) {
 
       {/* Version */}
       <div
-        className="mt-auto text-[10px] text-muted-foreground/50 transition-all duration-300"
+        className="mt-auto flex flex-col items-center gap-1.5 transition-all duration-300"
         style={{ paddingBottom: isPlayerOpen ? '7rem' : undefined }}
       >
-        v{version}
+        <span className="text-[10px] text-muted-foreground/50">v{version}</span>
+        {updateStatus.available && (
+          <Link
+            to="/settings"
+            className="text-[9px] font-semibold tracking-wide uppercase px-2 py-0.5 rounded-full bg-accent/15 text-accent hover:bg-accent/25 transition-colors"
+          >
+            Update
+          </Link>
+        )}
       </div>
     </div>
   );

app/src/components/ui/select.tsx

@@ -16,7 +16,7 @@ const SelectTrigger = React.forwardRef<
   <SelectPrimitive.Trigger
     ref={ref}
     className={cn(
-      'flex h-10 w-full items-center justify-between rounded-md border border-input bg-background px-3 py-2 text-sm ring-offset-background placeholder:text-muted-foreground focus:outline-none focus:ring-2 focus:ring-ring focus:ring-offset-2 disabled:cursor-not-allowed disabled:opacity-50 [&>span]:line-clamp-1',
+      'flex h-10 w-full items-center justify-between rounded-md border border-input bg-background px-3 py-2 text-sm ring-offset-background placeholder:text-muted-foreground focus:outline-none focus:bg-muted/50 disabled:cursor-not-allowed disabled:opacity-50 [&>span]:line-clamp-1',
       className,
     )}
     {...props}

app/src/components/ui/slider.tsx

@@ -1,5 +1,5 @@
-import * as React from 'react';
 import * as SliderPrimitive from '@radix-ui/react-slider';
+import * as React from 'react';
 import { cn } from '@/lib/utils/cn';
 
 const Slider = React.forwardRef<
@@ -14,7 +14,7 @@ const Slider = React.forwardRef<
     <SliderPrimitive.Track className="relative h-2 w-full grow overflow-hidden rounded-full bg-secondary">
       <SliderPrimitive.Range className="absolute h-full bg-primary" />
     </SliderPrimitive.Track>
-    <SliderPrimitive.Thumb className="block h-5 w-5 rounded-full border-2 border-primary bg-background ring-offset-background transition-colors focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-2 disabled:pointer-events-none disabled:opacity-50 translate-x-0.5" />
+    <SliderPrimitive.Thumb className="block h-0 w-0 outline-none disabled:pointer-events-none disabled:opacity-50 after:block after:h-5 after:w-5 after:rounded-full after:border-2 after:border-primary after:bg-background after:ring-offset-background after:transition-colors after:absolute after:top-1/2 after:left-1/2 after:-translate-x-1/2 after:-translate-y-1/2 focus-visible:after:ring-2 focus-visible:after:ring-ring focus-visible:after:ring-offset-2" />
   </SliderPrimitive.Root>
 ));
 Slider.displayName = SliderPrimitive.Root.displayName;

app/src/components/ui/toaster.tsx

@@ -1,3 +1,4 @@
+import { usePlayerStore } from '@/stores/playerStore';
 import {
   Toast,
   ToastClose,
@@ -10,6 +11,7 @@ import { useToast } from './use-toast';
 
 export function Toaster() {
   const { toasts } = useToast();
+  const isPlayerOpen = !!usePlayerStore((s) => s.audioUrl);
 
   return (
     <ToastProvider>
@@ -23,7 +25,7 @@ export function Toaster() {
           <ToastClose />
         </Toast>
       ))}
-      <ToastViewport />
+      <ToastViewport className={isPlayerOpen ? 'sm:bottom-44' : ''} />
     </ToastProvider>
   );
 }

app/src/components/ui/toggle.tsx

@@ -0,0 +1,48 @@
+import * as React from 'react';
+import { cn } from '@/lib/utils/cn';
+
+export interface ToggleProps {
+  checked?: boolean;
+  onCheckedChange?: (checked: boolean) => void;
+  disabled?: boolean;
+  className?: string;
+  id?: string;
+}
+
+const Toggle = React.forwardRef<HTMLButtonElement, ToggleProps>(
+  ({ checked = false, onCheckedChange, disabled = false, className, id, ...props }, ref) => {
+    return (
+      <button
+        type="button"
+        ref={ref}
+        id={id}
+        role="switch"
+        aria-checked={checked}
+        disabled={disabled}
+        onClick={() => {
+          if (!disabled && onCheckedChange) {
+            onCheckedChange(!checked);
+          }
+        }}
+        className={cn(
+          'relative inline-flex h-5 w-9 shrink-0 items-center rounded-full transition-colors',
+          'focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-2',
+          checked ? 'bg-accent' : 'bg-muted-foreground/25',
+          disabled ? 'opacity-50 cursor-not-allowed' : 'cursor-pointer',
+          className,
+        )}
+        {...props}
+      >
+        <span
+          className={cn(
+            'pointer-events-none block h-4 w-4 rounded-full bg-white shadow-sm transition-transform',
+            checked ? 'translate-x-[18px]' : 'translate-x-[2px]',
+          )}
+        />
+      </button>
+    );
+  },
+);
+Toggle.displayName = 'Toggle';
+
+export { Toggle };

app/src/global.d.ts

@@ -1,3 +1,8 @@
 interface Window {
   __voiceboxServerStartedByApp?: boolean;
 }
+
+declare module 'virtual:changelog' {
+  const raw: string;
+  export default raw;
+}

app/src/lib/api/client.ts

@@ -32,8 +32,24 @@ import type {
   TranscriptionResponse,
   VoiceProfileCreate,
   VoiceProfileResponse,
+  WhisperModelSize,
 } from './types';
 
+function formatErrorDetail(detail: unknown, fallback: string): string {
+  if (typeof detail === 'string') return detail;
+  if (Array.isArray(detail)) {
+    return detail
+      .map((e: Record<string, unknown>) => e.msg || e.message || JSON.stringify(e))
+      .join('; ');
+  }
+  if (detail && typeof detail === 'object') {
+    const obj = detail as Record<string, unknown>;
+    if (typeof obj.message === 'string') return obj.message;
+    return JSON.stringify(detail);
+  }
+  return fallback;
+}
+
 class ApiClient {
   private getBaseUrl(): string {
     const serverUrl = useServerStore.getState().serverUrl;
@@ -54,7 +70,7 @@ class ApiClient {
       const error = await response.json().catch(() => ({
         detail: response.statusText,
       }));
-      throw new Error(error.detail || `HTTP error! status: ${response.status}`);
+      throw new Error(formatErrorDetail(error.detail, `HTTP error! status: ${response.status}`));
     }
 
     return response.json();
@@ -113,7 +129,7 @@ class ApiClient {
       const error = await response.json().catch(() => ({
         detail: response.statusText,
       }));
-      throw new Error(error.detail || `HTTP error! status: ${response.status}`);
+      throw new Error(formatErrorDetail(error.detail, `HTTP error! status: ${response.status}`));
     }
 
     return response.json();
@@ -147,7 +163,7 @@ class ApiClient {
       const error = await response.json().catch(() => ({
         detail: response.statusText,
       }));
-      throw new Error(error.detail || `HTTP error! status: ${response.status}`);
+      throw new Error(formatErrorDetail(error.detail, `HTTP error! status: ${response.status}`));
     }
 
     return response.blob();
@@ -167,7 +183,7 @@ class ApiClient {
       const error = await response.json().catch(() => ({
         detail: response.statusText,
       }));
-      throw new Error(error.detail || `HTTP error! status: ${response.status}`);
+      throw new Error(formatErrorDetail(error.detail, `HTTP error! status: ${response.status}`));
     }
 
     return response.json();
@@ -187,7 +203,7 @@ class ApiClient {
       const error = await response.json().catch(() => ({
         detail: response.statusText,
       }));
-      throw new Error(error.detail || `HTTP error! status: ${response.status}`);
+      throw new Error(formatErrorDetail(error.detail, `HTTP error! status: ${response.status}`));
     }
 
     return response.json();
@@ -257,7 +273,7 @@ class ApiClient {
       const error = await response.json().catch(() => ({
         detail: response.statusText,
       }));
-      throw new Error(error.detail || `HTTP error! status: ${response.status}`);
+      throw new Error(formatErrorDetail(error.detail, `HTTP error! status: ${response.status}`));
     }
 
     return response.blob();
@@ -271,7 +287,7 @@ class ApiClient {
       const error = await response.json().catch(() => ({
         detail: response.statusText,
       }));
-      throw new Error(error.detail || `HTTP error! status: ${response.status}`);
+      throw new Error(formatErrorDetail(error.detail, `HTTP error! status: ${response.status}`));
     }
 
     return response.blob();
@@ -297,7 +313,7 @@ class ApiClient {
       const error = await response.json().catch(() => ({
         detail: response.statusText,
       }));
-      throw new Error(error.detail || `HTTP error! status: ${response.status}`);
+      throw new Error(formatErrorDetail(error.detail, `HTTP error! status: ${response.status}`));
     }
 
     return response.json();
@@ -318,12 +334,19 @@ class ApiClient {
   }
 
   // Transcription
-  async transcribeAudio(file: File, language?: LanguageCode): Promise<TranscriptionResponse> {
+  async transcribeAudio(
+    file: File,
+    language?: LanguageCode,
+    model?: WhisperModelSize,
+  ): Promise<TranscriptionResponse> {
     const formData = new FormData();
     formData.append('file', file);
     if (language) {
       formData.append('language', language);
     }
+    if (model) {
+      formData.append('model', model);
+    }
 
     const url = `${this.getBaseUrl()}/transcribe`;
     const response = await fetch(url, {
@@ -335,7 +358,7 @@ class ApiClient {
       const error = await response.json().catch(() => ({
         detail: response.statusText,
       }));
-      throw new Error(error.detail || `HTTP error! status: ${response.status}`);
+      throw new Error(formatErrorDetail(error.detail, `HTTP error! status: ${response.status}`));
     }
 
     return response.json();
@@ -608,7 +631,7 @@ class ApiClient {
       const error = await response.json().catch(() => ({
         detail: response.statusText,
       }));
-      throw new Error(error.detail || `HTTP error! status: ${response.status}`);
+      throw new Error(formatErrorDetail(error.detail, `HTTP error! status: ${response.status}`));
     }
 
     return response.blob();
@@ -705,7 +728,7 @@ class ApiClient {
       const error = await response.json().catch(() => ({
         detail: response.statusText,
       }));
-      throw new Error(error.detail || `HTTP error! status: ${response.status}`);
+      throw new Error(formatErrorDetail(error.detail, `HTTP error! status: ${response.status}`));
     }
 
     return response.blob();

app/src/lib/api/types.ts

@@ -73,7 +73,7 @@ export interface GenerationResponse {
   instruct?: string;
   engine?: string;
   model_size?: string;
-  status: 'generating' | 'completed' | 'failed';
+  status: 'loading_model' | 'generating' | 'completed' | 'failed';
   error?: string;
   is_favorited?: boolean;
   created_at: string;
@@ -99,8 +99,11 @@ export interface HistoryListResponse {
   total: number;
 }
 
+export type WhisperModelSize = 'base' | 'small' | 'medium' | 'large' | 'turbo';
+
 export interface TranscriptionRequest {
   language?: LanguageCode;
+  model?: WhisperModelSize;
 }
 
 export interface TranscriptionResponse {

app/src/lib/hooks/useGenerationProgress.ts

@@ -8,7 +8,7 @@ import { useServerStore } from '@/stores/serverStore';
 
 interface GenerationStatusEvent {
   id: string;
-  status: 'generating' | 'completed' | 'failed' | 'not_found';
+  status: 'loading_model' | 'generating' | 'completed' | 'failed' | 'not_found';
   duration?: number;
   error?: string;
 }
@@ -75,8 +75,8 @@ export function useGenerationProgress() {
             currentSources.delete(id);
             removePendingGeneration(id);
 
-            // Refresh history to pick up the completed generation
+            // Refetch history to pick up the completed generation
-            queryClient.invalidateQueries({ queryKey: ['history'] });
+            queryClient.refetchQueries({ queryKey: ['history'] });
 
             // If this generation was queued for a story, add it now
             const storyId = removePendingStoryAdd(id);
@@ -120,7 +120,7 @@ export function useGenerationProgress() {
             removePendingGeneration(id);
             removePendingStoryAdd(id);
 
-            queryClient.invalidateQueries({ queryKey: ['history'] });
+            queryClient.refetchQueries({ queryKey: ['history'] });
 
             toast({
               title: data.status === 'not_found' ? 'Generation not found' : 'Generation failed',
@@ -134,11 +134,12 @@ export function useGenerationProgress() {
       };
 
       source.onerror = () => {
-        // EventSource auto-reconnects, but if we get repeated errors
+        // SSE connection dropped — clean up and refresh history so any
-        // just clean up
+        // completed/failed generation still appears in the list
         source.close();
         currentSources.delete(id);
         removePendingGeneration(id);
+        queryClient.refetchQueries({ queryKey: ['history'] });
       };
 
       currentSources.set(id, source);

app/src/lib/hooks/useSystemAudioCapture.ts

@@ -1,4 +1,4 @@
-import { useState, useRef, useCallback, useEffect } from 'react';
+import { useCallback, useEffect, useRef, useState } from 'react';
 import { usePlatform } from '@/platform/PlatformContext';
 
 interface UseSystemAudioCaptureOptions {
@@ -94,15 +94,13 @@ export function useSystemAudioCapture({
       const blob = await platform.audio.stopSystemAudioCapture();
 
       // Pass the actual recorded duration
-      const recordedDuration = startTimeRef.current 
+      const recordedDuration = startTimeRef.current
-        ? (Date.now() - startTimeRef.current) / 1000 
+        ? (Date.now() - startTimeRef.current) / 1000
         : undefined;
       onRecordingComplete?.(blob, recordedDuration);
     } catch (err) {
       const errorMessage =
-        err instanceof Error
+        err instanceof Error ? err.message : 'Failed to stop system audio capture.';
-          ? err.message
-          : 'Failed to stop system audio capture.';
       setError(errorMessage);
     }
   }, [isRecording, onRecordingComplete, platform]);

app/src/lib/hooks/useTranscription.ts

@@ -1,10 +1,18 @@
 import { useMutation } from '@tanstack/react-query';
 import { apiClient } from '@/lib/api/client';
+import type { WhisperModelSize } from '@/lib/api/types';
 import type { LanguageCode } from '@/lib/constants/languages';
 
 export function useTranscription() {
   return useMutation({
-    mutationFn: ({ file, language }: { file: File; language?: LanguageCode }) =>
+    mutationFn: ({
-      apiClient.transcribeAudio(file, language),
+      file,
+      language,
+      model,
+    }: {
+      file: File;
+      language?: LanguageCode;
+      model?: WhisperModelSize;
+    }) => apiClient.transcribeAudio(file, language, model),
   });
 }

app/src/lib/utils/parseChangelog.ts

@@ -0,0 +1,37 @@
+export interface ChangelogEntry {
+  version: string;
+  date: string | null;
+  body: string;
+}
+
+/**
+ * Parses a Keep-a-Changelog style markdown string into structured entries.
+ *
+ * Splits on `## [version]` headings and extracts the version + date from each.
+ * The body is the raw markdown between headings (trimmed), with the leading
+ * `# Changelog` title and trailing link references stripped.
+ */
+export function parseChangelog(raw: string): ChangelogEntry[] {
+  const entries: ChangelogEntry[] = [];
+
+  // Strip trailing link reference definitions (e.g. [0.1.0]: https://...)
+  const cleaned = raw.replace(/^\[[\w.]+\]:.*$/gm, '').trimEnd();
+
+  // Match `## [version]` or `## [version] - date`
+  const headingRe = /^## \[(.+?)\](?:\s*-\s*(.+))?$/gm;
+  const matches = [...cleaned.matchAll(headingRe)];
+
+  for (let i = 0; i < matches.length; i++) {
+    const match = matches[i];
+    const version = match[1];
+    const date = match[2]?.trim() || null;
+
+    const start = match.index! + match[0].length;
+    const end = i + 1 < matches.length ? matches[i + 1].index! : cleaned.length;
+    const body = cleaned.slice(start, end).trim();
+
+    entries.push({ version, date, body });
+  }
+
+  return entries;
+}

app/src/platform/types.ts

@@ -50,12 +50,18 @@ export interface PlatformAudio {
   stopPlayback(): void;
 }
 
+export interface ServerLogEntry {
+  stream: 'stdout' | 'stderr';
+  line: string;
+}
+
 export interface PlatformLifecycle {
   startServer(remote?: boolean, modelsDir?: string | null): Promise<string>;
   stopServer(): Promise<void>;
   restartServer(modelsDir?: string | null): Promise<string>;
   setKeepServerRunning(keep: boolean): Promise<void>;
   setupWindowCloseHandler(): Promise<void>;
+  subscribeToServerLogs(callback: (entry: ServerLogEntry) => void): () => void;
   onServerReady?: () => void;
 }
 

app/src/router.tsx

@@ -1,10 +1,22 @@
-import { createRootRoute, createRoute, createRouter, Outlet } from '@tanstack/react-router';
+import {
+  createRootRoute,
+  createRoute,
+  createRouter,
+  Outlet,
+  redirect,
+} from '@tanstack/react-router';
 import { AppFrame } from '@/components/AppFrame/AppFrame';
 import { AudioTab } from '@/components/AudioTab/AudioTab';
 import { EffectsTab } from '@/components/EffectsTab/EffectsTab';
 import { MainEditor } from '@/components/MainEditor/MainEditor';
 import { ModelsTab } from '@/components/ModelsTab/ModelsTab';
-import { ServerTab } from '@/components/ServerTab/ServerTab';
+import { AboutPage } from '@/components/ServerTab/AboutPage';
+import { ChangelogPage } from '@/components/ServerTab/ChangelogPage';
+import { GeneralPage } from '@/components/ServerTab/GeneralPage';
+import { GenerationPage } from '@/components/ServerTab/GenerationPage';
+import { GpuPage } from '@/components/ServerTab/GpuPage';
+import { LogsPage } from '@/components/ServerTab/LogsPage';
+import { SettingsLayout } from '@/components/ServerTab/ServerTab';
 import { Sidebar } from '@/components/Sidebar';
 import { StoriesTab } from '@/components/StoriesTab/StoriesTab';
 import { Toaster } from '@/components/ui/toaster';
@@ -120,11 +132,57 @@ const modelsRoute = createRoute({
   component: ModelsTab,
 });
 
-// Server route
+// Settings layout route (parent for sub-tabs)
-const serverRoute = createRoute({
+const settingsRoute = createRoute({
+  getParentRoute: () => rootRoute,
+  path: '/settings',
+  component: SettingsLayout,
+});
+
+// Settings sub-routes
+const settingsGeneralRoute = createRoute({
+  getParentRoute: () => settingsRoute,
+  path: '/',
+  component: GeneralPage,
+});
+
+const settingsGenerationRoute = createRoute({
+  getParentRoute: () => settingsRoute,
+  path: '/generation',
+  component: GenerationPage,
+});
+
+const settingsGpuRoute = createRoute({
+  getParentRoute: () => settingsRoute,
+  path: '/gpu',
+  component: GpuPage,
+});
+
+const settingsChangelogRoute = createRoute({
+  getParentRoute: () => settingsRoute,
+  path: '/changelog',
+  component: ChangelogPage,
+});
+
+const settingsLogsRoute = createRoute({
+  getParentRoute: () => settingsRoute,
+  path: '/logs',
+  component: LogsPage,
+});
+
+const settingsAboutRoute = createRoute({
+  getParentRoute: () => settingsRoute,
+  path: '/about',
+  component: AboutPage,
+});
+
+// Redirect old /server path to /settings
+const serverRedirectRoute = createRoute({
   getParentRoute: () => rootRoute,
   path: '/server',
-  component: ServerTab,
+  beforeLoad: () => {
+    throw redirect({ to: '/settings' });
+  },
 });
 
 // Route tree
@@ -135,7 +193,15 @@ const routeTree = rootRoute.addChildren([
   audioRoute,
   effectsRoute,
   modelsRoute,
-  serverRoute,
+  settingsRoute.addChildren([
+    settingsGeneralRoute,
+    settingsGenerationRoute,
+    settingsGpuRoute,
+    settingsLogsRoute,
+    settingsChangelogRoute,
+    settingsAboutRoute,
+  ]),
+  serverRedirectRoute,
 ]);
 
 // Create router

app/src/stores/logStore.ts

@@ -0,0 +1,31 @@
+import { create } from 'zustand';
+import type { ServerLogEntry } from '@/platform/types';
+
+const MAX_LOG_ENTRIES = 2000;
+
+let nextLogEntryId = 0;
+
+export interface LogEntry extends ServerLogEntry {
+  id: number;
+  timestamp: number;
+}
+
+interface LogStore {
+  entries: LogEntry[];
+  addEntry: (entry: ServerLogEntry) => void;
+  clear: () => void;
+}
+
+export const useLogStore = create<LogStore>((set) => ({
+  entries: [],
+  addEntry: (entry) =>
+    set((state) => {
+      const newEntry: LogEntry = { ...entry, id: nextLogEntryId++, timestamp: Date.now() };
+      const entries = [...state.entries, newEntry];
+      if (entries.length > MAX_LOG_ENTRIES) {
+        return { entries: entries.slice(entries.length - MAX_LOG_ENTRIES) };
+      }
+      return { entries };
+    }),
+  clear: () => set({ entries: [] }),
+}));

app/tsconfig.node.json

@@ -6,5 +6,5 @@
     "moduleResolution": "bundler",
     "allowSyntheticDefaultImports": true
   },
-  "include": ["vite.config.ts"]
+  "include": ["vite.config.ts", "plugins/**/*.ts"]
 }

app/vite.config.ts

@@ -2,9 +2,10 @@ import path from 'node:path';
 import tailwindcss from '@tailwindcss/vite';
 import react from '@vitejs/plugin-react';
 import { defineConfig } from 'vite';
+import { changelogPlugin } from './plugins/changelog';
 
 export default defineConfig({
-  plugins: [tailwindcss(), react()],
+  plugins: [tailwindcss(), react(), changelogPlugin(path.resolve(__dirname, '..'))],
   resolve: {
     alias: {
       '@': path.resolve(__dirname, './src'),

backend/README.md

@@ -1,462 +1,135 @@
-# voicebox Backend
+# Voicebox Backend
 
-Production-quality FastAPI backend for Qwen3-TTS voice cloning.
+FastAPI server powering voice cloning, speech generation, and audio processing. Runs locally as a Tauri sidecar or standalone via `python -m backend.main`.
 
-## Features
+## Running
 
-- ✅ **Voice Profile Management** - Create, update, delete voice profiles with multi-sample support
+```bash
-- ✅ **Voice Cloning** - Generate speech using voice profiles with caching
+# Via justfile (recommended)
-- ✅ **Generation History** - Full history tracking with search and filtering
+just dev:server
-- ✅ **Transcription** - Whisper-based audio transcription
+
-- ✅ **Multi-Sample Profiles** - Combine multiple reference samples for better quality
+# Standalone
-- ✅ **Voice Prompt Caching** - Dual memory + disk caching for fast generation
+python -m backend.main --host 127.0.0.1 --port 17493
-- ✅ **Audio Validation** - Automatic validation of reference audio quality
+
-- ✅ **Model Management** - Lazy loading and VRAM management
+# With custom data directory
+python -m backend.main --data-dir /path/to/data
+```
+
+The server auto-initializes the SQLite database on first startup. Models are downloaded from HuggingFace on first use.
 
 ## Architecture
 
 ```
 backend/
-├── main.py              # FastAPI app with all routes
+  app.py                  # FastAPI app factory, CORS, lifecycle events
-├── models.py            # Pydantic request/response models
+  main.py                 # Entry point (imports app, runs uvicorn)
-├── platform_detect.py   # Platform detection for backend selection
+  config.py               # Data directory paths and configuration
-├── tts.py              # TTS backend abstraction (delegates to MLX or PyTorch)
+  models.py               # Pydantic request/response schemas
-├── transcribe.py       # STT backend abstraction (delegates to MLX or PyTorch)
+  server.py               # Tauri sidecar launcher, parent-pid watchdog
-├── backends/           # Backend implementations
+
-│   ├── __init__.py     # Backend factory and protocols
+  routes/                 # Thin HTTP handlers — validation, delegation, response formatting
-│   ├── mlx_backend.py  # MLX backend (Apple Silicon)
+  services/               # Business logic, CRUD, orchestration
-│   └── pytorch_backend.py  # PyTorch backend (Windows/Linux/Intel)
+  backends/               # TTS/STT engine implementations (MLX, PyTorch, etc.)
-├── profiles.py         # Voice profile CRUD
+  database/               # ORM models, session management, migrations, seed data
-├── history.py          # Generation history
+  utils/                  # Shared utilities (audio, effects, caching, progress tracking)
-├── studio.py           # Audio editing (TODO)
-├── database.py         # SQLite ORM
-└── utils/
-    ├── audio.py        # Audio processing utilities
-    ├── cache.py        # Voice prompt caching
-    └── validation.py   # Input validation
 ```
 
-### Backend Selection
+### Request flow
-
-Voicebox automatically selects the best backend based on platform:
-
-- **Apple Silicon (M1/M2/M3)**: Uses MLX backend with native Metal acceleration (4-5x faster)
-- **Windows/Linux/Intel Mac**: Uses PyTorch backend (CUDA GPU if available, CPU fallback)
-
-The backend is detected at runtime via `platform_detect.py`. Both backends implement the same interface, so the API remains consistent across platforms.
-
-## API Endpoints
-
-### Health & Info
-
-#### `GET /`
-Root endpoint with version info.
-
-#### `GET /health`
-Health check with model status.
-
-**Response:**
-```json
-{
-  "status": "healthy",
-  "model_loaded": true,
-  "gpu_available": true,
-  "gpu_type": "Metal (Apple Silicon via MLX)",
-  "backend_type": "mlx",
-  "vram_used_mb": null
-}
-```
-
-**Backend Types:**
-- `"mlx"` - MLX backend (Apple Silicon with Metal acceleration)
-- `"pytorch"` - PyTorch backend (Windows/Linux/Intel Mac)
-
-### Voice Profiles
-
-**Note:** The database is automatically initialized when the server starts. No manual setup required.
-
-#### `POST /profiles`
-Create a new voice profile.
-
-**Request:**
-```json
-{
-  "name": "My Voice",
-  "description": "Optional description",
-  "language": "en"
-}
-```
-
-**Response:**
-```json
-{
-  "id": "uuid",
-  "name": "My Voice",
-  "description": "Optional description",
-  "language": "en",
-  "created_at": "2024-01-01T00:00:00Z",
-  "updated_at": "2024-01-01T00:00:00Z"
-}
-```
-
-#### `GET /profiles`
-List all voice profiles.
-
-#### `GET /profiles/{profile_id}`
-Get a specific profile.
-
-#### `PUT /profiles/{profile_id}`
-Update a profile.
-
-#### `DELETE /profiles/{profile_id}`
-Delete a profile and all associated samples.
-
-#### `POST /profiles/{profile_id}/samples`
-Add a sample to a profile.
-
-**Form Data:**
-- `file`: Audio file (WAV, MP3, etc.)
-- `reference_text`: Transcript of the audio
-
-**Response:**
-```json
-{
-  "id": "sample-uuid",
-  "profile_id": "profile-uuid",
-  "audio_path": "/path/to/sample.wav",
-  "reference_text": "This is my voice"
-}
-```
-
-#### `GET /profiles/{profile_id}/samples`
-List all samples for a profile.
-
-#### `DELETE /profiles/samples/{sample_id}`
-Delete a specific sample.
-
-### Generation
-
-#### `POST /generate`
-Generate speech from text using a voice profile.
-
-**Request:**
-```json
-{
-  "profile_id": "uuid",
-  "text": "Hello, this is a test.",
-  "language": "en",
-  "seed": 42
-}
-```
-
-**Response:**
-```json
-{
-  "id": "generation-uuid",
-  "profile_id": "profile-uuid",
-  "text": "Hello, this is a test.",
-  "language": "en",
-  "audio_path": "/path/to/audio.wav",
-  "duration": 2.5,
-  "seed": 42,
-  "created_at": "2024-01-01T00:00:00Z"
-}
-```
-
-### History
-
-#### `GET /history`
-List generation history with optional filters.
-
-**Query Parameters:**
-- `profile_id` (optional): Filter by profile
-- `search` (optional): Search in text content
-- `limit` (default: 50): Results per page
-- `offset` (default: 0): Pagination offset
-
-#### `GET /history/{generation_id}`
-Get a specific generation.
-
-#### `DELETE /history/{generation_id}`
-Delete a generation.
-
-#### `GET /history/stats`
-Get generation statistics.
-
-**Response:**
-```json
-{
-  "total_generations": 100,
-  "total_duration_seconds": 250.5,
-  "generations_by_profile": {
-    "profile-uuid-1": 50,
-    "profile-uuid-2": 50
-  }
-}
-```
-
-### Audio Files
-
-#### `GET /audio/{generation_id}`
-Download generated audio file.
-
-Returns WAV file with appropriate headers.
-
-### Transcription
-
-#### `POST /transcribe`
-Transcribe audio file to text.
-
-**Form Data:**
-- `file`: Audio file
-- `language` (optional): Language hint (en or zh)
-
-**Response:**
-```json
-{
-  "text": "Transcribed text here",
-  "duration": 5.5
-}
-```
-
-### Model Management
-
-#### `POST /models/load`
-Manually load TTS model.
-
-**Query Parameters:**
-- `model_size`: Model size (1.7B or 0.6B)
-
-#### `POST /models/unload`
-Unload TTS model to free memory.
-
-## Database Schema
-
-### profiles
-- `id`: UUID primary key
-- `name`: Profile name (unique)
-- `description`: Optional description
-- `language`: Language code (en/zh)
-- `created_at`: Creation timestamp
-- `updated_at`: Last update timestamp
-
-### profile_samples
-- `id`: UUID primary key
-- `profile_id`: Foreign key to profiles
-- `audio_path`: Path to audio file
-- `reference_text`: Transcript
-
-### generations
-- `id`: UUID primary key
-- `profile_id`: Foreign key to profiles
-- `text`: Generated text
-- `language`: Language code
-- `audio_path`: Path to audio file
-- `duration`: Duration in seconds
-- `seed`: Random seed (optional)
-- `created_at`: Creation timestamp
-
-### projects
-- `id`: UUID primary key
-- `name`: Project name
-- `data`: JSON data
-- `created_at`: Creation timestamp
-- `updated_at`: Last update timestamp
-
-## File Structure
 
 ```
-data/
+HTTP request
-├── profiles/
+  -> routes/        (validate input, parse params)
-│   └── {profile_id}/
+  -> services/      (business logic, database queries, orchestration)
-│       ├── {sample_id}.wav
+  -> backends/      (TTS/STT inference)
-│       └── ...
+  -> utils/         (audio processing, effects, caching)
-├── generations/
-│   └── {generation_id}.wav
-├── cache/
-│   └── {hash}.prompt
-├── projects/
-│   └── {project_id}.json
-└── voicebox.db
 ```
 
-## Setup
+Route handlers are intentionally thin. They validate input, delegate to a service function, and format the response. All business logic lives in `services/`.
 
-### 1. Install Dependencies
+### Key modules
-
+
-```bash
+**services/generation.py** -- Single `run_generation()` function that handles all three generation modes (generate, retry, regenerate). Manages model loading, voice prompt creation, chunked inference, normalization, effects, and version persistence.
-pip install -r requirements.txt
+
-```
+**services/task_queue.py** -- Serial generation queue. Ensures only one GPU inference runs at a time. Background tasks are tracked to prevent garbage collection.
-
+
-**Note:** On Apple Silicon, also install MLX dependencies for faster inference:
+**backends/__init__.py** -- Protocol definitions (`TTSBackend`, `STTBackend`), model config registry, and factory functions. Adding a new engine means implementing the protocol and registering a config entry.
-```bash
+
-pip install -r requirements-mlx.txt
+**backends/base.py** -- Shared utilities used across all engine implementations: HuggingFace cache checks, device detection, voice prompt combination, progress tracking.
-```
+
-
+**database/** -- SQLAlchemy ORM models with a re-exporting `__init__.py` for backward compatibility. Migrations run automatically on startup.
-### 2. Download Models (Automatic)
+
-
+### Backend selection
-The Qwen3-TTS models are automatically downloaded from HuggingFace Hub on first use, similar to how Whisper models work.
+
-
+The server detects the best inference backend at startup:
-**No manual download required!** The models will be cached locally after the first download.
+
-
+| Platform | Backend | Acceleration |
-Available models:
+|----------|---------|-------------|
-- **1.7B** (recommended): `Qwen/Qwen3-TTS-12Hz-1.7B-Base` (~4GB)
+| macOS (Apple Silicon) | MLX | Metal / Neural Engine |
-- **0.6B** (faster): `Qwen/Qwen3-TTS-12Hz-0.6B-Base` (~2GB)
+| Windows / Linux (NVIDIA) | PyTorch | CUDA |
-
+| Linux (AMD) | PyTorch | ROCm |
-**Note:** The first generation will take longer as the model downloads. Subsequent generations will use the cached model.
+| Intel Arc | PyTorch | IPEX / XPU |
-
+| Windows (any GPU) | PyTorch | DirectML |
-#### Manual Download (Optional)
+| Any | PyTorch | CPU fallback |
-
+
-If you prefer to download models manually or have limited internet during runtime:
+Detection is handled by `utils/platform_detect.py`. Both backends implement the same `TTSBackend` protocol, so the API layer is engine-agnostic.
-
+
-```bash
+## API
-# Install huggingface-cli
+
-pip install huggingface_hub
+90 endpoints organized by domain. Full interactive documentation available at `http://localhost:17493/docs` when the server is running.
-
+
-# Download 1.7B model
+| Domain | Prefix | Description |
-huggingface-cli download Qwen/Qwen3-TTS-12Hz-1.7B-Base
+|--------|--------|-------------|
-
+| Health | `/`, `/health` | Server status, GPU info, filesystem checks |
-# Or use Python
+| Profiles | `/profiles` | Voice profile CRUD, samples, avatars, import/export |
-python -c "from huggingface_hub import snapshot_download; snapshot_download('Qwen/Qwen3-TTS-12Hz-1.7B-Base')"
+| Channels | `/channels` | Audio channel management and voice assignment |
-```
+| Generation | `/generate` | TTS generation, retry, regenerate, status SSE |
-
+| History | `/history` | Generation history, search, favorites, export |
-Models are cached in `~/.cache/huggingface/hub/` by default.
+| Transcription | `/transcribe` | Whisper-based audio-to-text |
-
+| Stories | `/stories` | Multi-track timeline editor, audio export |
-### 4. Run Server
+| Effects | `/effects` | Effect presets, preview, version management |
-
+| Audio | `/audio`, `/samples` | Audio file serving |
-```bash
+| Models | `/models` | Load, unload, download, migrate, status |
-# Development (local only)
+| Tasks | `/tasks`, `/cache` | Active task tracking, cache management |
-python -m backend.main
+| CUDA | `/backend/cuda-*` | CUDA binary download and management |
-
+
-# Production (allow remote access)
+### Quick examples
-python -m backend.main --host 0.0.0.0 --port 8000
-```
-
-## Usage Examples
-
-The desktop app, web client, and current development workflow use `http://localhost:17493` by default.
-If you launch the backend manually with a different host or port, substitute that address in the examples below.
-
-### Creating a Voice Profile
-
-```bash
-# 1. Create profile
-curl -X POST http://localhost:17493/profiles \
-  -H "Content-Type: application/json" \
-  -d '{"name": "My Voice", "language": "en"}'
-
-# Response: {"id": "abc-123", ...}
-
-# 2. Add sample
-curl -X POST http://localhost:17493/profiles/abc-123/samples \
-  -F "[email protected]" \
-  -F "reference_text=This is my voice sample"
-```
-
-### Generating Speech
 
 ```bash
+# Generate speech
 curl -X POST http://localhost:17493/generate \
   -H "Content-Type: application/json" \
-  -d '{
+  -d '{"text": "Hello world", "profile_id": "...", "language": "en"}'
-    "profile_id": "abc-123",
-    "text": "Hello, this is a test.",
-    "language": "en",
-    "seed": 42
-  }'
 
-# Response: {"id": "gen-456", "audio_path": "/path/to/audio.wav", ...}
+# List profiles
+curl http://localhost:17493/profiles
 
-# Download audio
+# Stream generation status (SSE)
-curl http://localhost:17493/audio/gen-456 -o output.wav
+curl http://localhost:17493/generate/{id}/status
 ```
 
-### Transcribing Audio
+## Data directory
+
+```
+{data_dir}/
+  voicebox.db             # SQLite database
+  profiles/{id}/          # Voice samples per profile
+  generations/            # Generated audio files
+  cache/                  # Voice prompt cache (memory + disk)
+  backends/               # Downloaded CUDA binary (if applicable)
+```
+
+Default location is the OS-specific app data directory. Override with `--data-dir` or the `VOICEBOX_DATA_DIR` environment variable.
+
+## Code quality
+
+Linting and formatting are enforced by [ruff](https://docs.astral.sh/ruff/), configured in `pyproject.toml`. See `STYLE_GUIDE.md` for conventions.
 
 ```bash
-curl -X POST http://localhost:17493/transcribe \
+just check-python       # lint + format check
-  -F "[email protected]" \
+just fix-python         # auto-fix lint issues + reformat
-  -F "language=en"
+just test               # run pytest
-
-# Response: {"text": "Transcribed text", "duration": 5.5}
 ```
 
-## Advanced Features
+## Dependencies
 
-### Multi-Sample Profiles
+Runtime dependencies are in `requirements.txt`. macOS-only MLX dependencies are in `requirements-mlx.txt`. Dev tools (ruff, pytest) are installed automatically by `just setup-python`.
-
-Add multiple samples to a profile for better quality:
-
-```bash
-# Add first sample
-curl -X POST http://localhost:17493/profiles/abc-123/samples \
-  -F "[email protected]" \
-  -F "reference_text=First sample"
-
-# Add second sample
-curl -X POST http://localhost:17493/profiles/abc-123/samples \
-  -F "[email protected]" \
-  -F "reference_text=Second sample"
-
-# Generation will automatically combine all samples
-```
-
-### Voice Prompt Caching
-
-Voice prompts are automatically cached for faster generation:
-- First generation: ~5-10 seconds (creates prompt)
-- Subsequent generations: ~1-2 seconds (uses cached prompt)
-
-Cache is stored in `data/cache/` and persists across server restarts.
-
-### VRAM Management
-
-Models are lazy-loaded and can be manually unloaded:
-
-```bash
-# Unload TTS model
-curl -X POST http://localhost:17493/models/unload
-
-# Load specific model size
-curl -X POST "http://localhost:17493/models/load?model_size=0.6B"
-```
-
-## Error Handling
-
-All endpoints return proper HTTP status codes:
-
-- `200 OK`: Success
-- `400 Bad Request`: Invalid input
-- `404 Not Found`: Resource not found
-- `500 Internal Server Error`: Server error
-
-Error responses include details:
-
-```json
-{
-  "detail": "Profile not found"
-}
-```
-
-## Performance Tips
-
-1. **Use multi-sample profiles** - Better quality than single sample
-2. **Let caching work** - Voice prompts are cached automatically
-3. **Use 0.6B model on CPU** - Faster than 1.7B with acceptable quality
-4. **Use 1.7B model on GPU** - Best quality, still fast
-5. **Unload Whisper after transcription** - Frees VRAM for TTS
-
-## TODO
-
-- [ ] WebSocket support for generation progress
-- [ ] Batch generation endpoint
-- [ ] Audio effects (M3GAN, etc.)
-- [ ] Voice design (text-to-voice)
-- [ ] Audio studio timeline features
-- [ ] Project management
-- [ ] Authentication & rate limiting
-- [ ] Export/import profiles
-
-## License
-
-See main project LICENSE.

backend/STYLE_GUIDE.md

@@ -0,0 +1,404 @@
+# Python Style Guide
+
+Target: **Python 3.12+** | Formatter/Linter: **Ruff** | Config: `backend/pyproject.toml`
+
+This guide codifies the conventions used across the backend, and prescribes the target style for code written during the refactor (Phases 3-6). Existing code should be migrated incrementally -- don't reformat entire files in unrelated PRs.
+
+---
+
+## Formatting
+
+Enforced by `ruff format` (Black-compatible).
+
+- **Line length**: 120 characters.
+- **Indent**: 4 spaces. No tabs.
+- **Trailing commas**: Required on multi-line function signatures, arguments, collections.
+- **Quotes**: Double quotes (`"`) for strings. Single quotes are acceptable in f-string expressions and dict keys inside f-strings where avoiding escapes improves readability.
+
+Run: `ruff format backend/`
+
+---
+
+## Imports
+
+Enforced by ruff's `isort` rules (rule set `I`).
+
+**Grouping** -- three blocks separated by a blank line:
+
+```python
+import asyncio                          # 1. stdlib
+from pathlib import Path
+
+import numpy as np                      # 2. third-party
+from fastapi import APIRouter, HTTPException
+from sqlalchemy.orm import Session
+
+from backend.config import get_data_dir  # 3. local (absolute)
+from .database import get_db            #    or relative
+```
+
+**Rules:**
+- Within the `backend` package, use **relative imports** for sibling/child modules: `from .database import get_db`, `from ..utils.audio import load_audio`.
+- Absolute imports are fine for top-level references from entry points (`main.py`, `server.py`).
+- Never use wildcard imports (`from module import *`).
+- One import per line for `from X import Y` when there are 4+ names; below that, comma-separated is fine.
+- **Lazy imports** are acceptable for heavy dependencies (torch, transformers, mlx) inside functions to reduce startup time. Add a comment: `# lazy: heavy import`.
+
+---
+
+## Type Annotations
+
+Python 3.12 means we use **built-in generics and union syntax natively**. No `from __future__ import annotations`, no `typing.List`/`typing.Dict`.
+
+```python
+# Yes
+def process(items: list[str], config: dict[str, int] | None = None) -> tuple[int, str]: ...
+
+# No
+from typing import List, Dict, Optional, Tuple
+def process(items: List[str], config: Optional[Dict[str, int]] = None) -> Tuple[int, str]: ...
+```
+
+**What to annotate:**
+- All public function signatures (parameters + return type).
+- Private functions: parameters at minimum; return type encouraged.
+- Module-level variables: only when the type isn't obvious from the assignment.
+- Route handlers: parameters are annotated via FastAPI's dependency injection. Add explicit `-> SomeResponse` return types when the route doesn't use `response_model`.
+
+**Imports from `typing` that are still needed** (no built-in equivalent):
+`Literal`, `TypeAlias`, `Protocol`, `runtime_checkable`, `Callable`, `Any`, `ClassVar`, `TypeVar`, `overload`, `TYPE_CHECKING`.
+
+Use `collections.abc` for abstract types: `Sequence`, `Mapping`, `Iterable`, `Iterator`, `Generator`.
+
+---
+
+## Naming
+
+| Thing | Convention | Example |
+|-------|-----------|---------|
+| Module | `snake_case` | `task_queue.py` |
+| Class | `PascalCase` | `ProgressManager` |
+| Function / method | `snake_case` | `create_profile` |
+| Variable | `snake_case` | `sample_rate` |
+| Constant | `UPPER_SNAKE_CASE` | `DEFAULT_SAMPLE_RATE` |
+| Private | `_leading_underscore` | `_generation_queue` |
+| Type alias | `PascalCase` | `EffectChain = list[dict[str, Any]]` |
+
+**Specific conventions:**
+- Database ORM models imported with `DB` prefix alias: `from .database import VoiceProfile as DBVoiceProfile`.
+- Pydantic models use descriptive suffixes: `VoiceProfileCreate`, `VoiceProfileResponse`, `GenerationRequest`.
+- Backend classes use engine-name prefix: `MLXTTSBackend`, `PyTorchSTTBackend`.
+
+---
+
+## Docstrings
+
+**Google style**. Required on all public functions, classes, and modules.
+
+```python
+def combine_voice_prompts(
+    profile_dir: Path,
+    *,
+    target_sr: int = 24000,
+) -> tuple[np.ndarray, int]:
+    """Load and concatenate all voice prompt files for a profile.
+
+    Reads .wav/.mp3/.flac files from the profile directory, resamples to
+    the target sample rate, normalizes, and concatenates into a single array.
+
+    Args:
+        profile_dir: Path to the voice profile directory containing audio files.
+        target_sr: Target sample rate for the output. Defaults to 24000.
+
+    Returns:
+        Tuple of (concatenated audio array, sample rate).
+
+    Raises:
+        FileNotFoundError: If profile_dir does not exist.
+        ValueError: If no valid audio files are found.
+    """
+```
+
+**Short form** is fine for simple functions:
+
+```python
+def get_db_path() -> Path:
+    """Get the path to the SQLite database file."""
+```
+
+**When to skip**: Private helpers under ~5 lines where the name and signature make intent obvious.
+
+**Module docstrings**: A single sentence at the top of every file describing its purpose.
+
+```python
+"""Voice profile CRUD operations."""
+```
+
+---
+
+## Comments
+
+Comments explain **why**, not **what**. If the code needs a comment to explain what it does, the code should be rewritten to be clearer. The exceptions are non-obvious performance choices, external constraints, and concurrency/race-condition reasoning -- those always deserve a comment.
+
+### No section dividers
+
+Do not use ASCII dividers to create visual sections in files:
+
+```python
+# No -- any of these:
+# ============================================
+# GENERATION ENDPOINTS
+# ============================================
+
+# ---------------------------------------------------------------------------
+# Device detection
+# ---------------------------------------------------------------------------
+
+# --- Load model --------------------------------------------------
+```
+
+If a file needs section dividers to be navigable, the file is too long. Split it into modules. Within a function, if you need labeled sections to follow the logic, extract those sections into named functions.
+
+### Inline comments
+
+Inline comments (end-of-line) are fine when they add information the code can't express:
+
+```python
+# Yes -- explains a non-obvious constraint or gives context:
+audio, sr = load_audio(path, sr=24000)  # Qwen expects 24kHz mono
+_generation_queue: asyncio.Queue = None  # type: ignore  # initialized at startup
+"tauri://localhost",         # Tauri webview (macOS)
+
+# No -- restates the code:
+# Check if profile name already exists
+existing = db.query(DBVoiceProfile).filter_by(name=data.name).first()
+
+# Delete from database
+db.delete(sample)
+
+# Update fields
+profile.name = data.name
+```
+
+Delete comments that narrate what the next line of code obviously does. If the function name, variable name, or method call already communicates intent, the comment is noise.
+
+### Block comments
+
+Use block comments for **why** explanations -- constraints, workarounds, non-obvious decisions:
+
+```python
+# PyInstaller + multiprocessing: child processes re-execute the frozen binary
+# with internal arguments. freeze_support() handles this and exits early.
+multiprocessing.freeze_support()
+
+# Mark any stale "generating" records as failed -- these are leftovers
+# from a previous process that was killed mid-generation.
+db.query(Generation).filter_by(status="generating").update({"status": "failed"})
+```
+
+Keep block comments tight. Two to three lines is normal. If you need a paragraph, it probably belongs in the docstring or a design doc.
+
+### Linter/type-checker suppression
+
+Always add a reason after `noqa` and `type: ignore`:
+
+```python
+import intel_extension_for_pytorch  # noqa: F401 -- side-effect import enables XPU
+_queue: asyncio.Queue = None  # type: ignore[assignment]  # initialized at startup
+```
+
+Bare `# noqa` or `# type: ignore` with no explanation are not allowed.
+
+### TODO / FIXME
+
+Use sparingly. Every `TODO` must include a brief description of what needs doing. Don't use them as a substitute for tracking work properly:
+
+```python
+# TODO: replace with async SQLAlchemy once CRUD modules are migrated (Phase 5)
+result = await asyncio.to_thread(profiles.get_profile, profile_id, db)
+```
+
+Never commit `HACK`, `XXX`, or `FIXME` -- fix the problem or file an issue.
+
+### Commented-out code
+
+Delete it. That's what git is for. If you need to document that something was intentionally removed, a short tombstone comment is acceptable:
+
+```python
+# Removed config.json-only check -- too lenient, doesn't confirm weights exist.
+```
+
+---
+
+## Error Handling
+
+The refactor is standardizing on a **two-layer pattern**:
+
+### 1. Domain layer -- raise plain exceptions
+
+CRUD modules and services raise `ValueError`, `FileNotFoundError`, or (post-refactor) custom exceptions defined in `backend/errors.py`:
+
+```python
+# backend/errors.py  (to be created in Phase 4)
+class NotFoundError(Exception):
+    """Raised when a requested resource does not exist."""
+
+class ConflictError(Exception):
+    """Raised on uniqueness constraint violations."""
+```
+
+```python
+# In a service or CRUD module:
+raise NotFoundError(f"Profile {profile_id} not found")
+```
+
+### 2. Route layer -- translate to HTTPException
+
+Route handlers catch domain exceptions and convert:
+
+```python
+@router.post("/profiles")
+async def create_profile(data: VoiceProfileCreate, db: Session = Depends(get_db)):
+    try:
+        return await profiles.create_profile(data, db)
+    except ConflictError as e:
+        raise HTTPException(status_code=409, detail=str(e))
+```
+
+**Background tasks** catch `Exception` broadly, log with `logger.exception()`, and update the task status to `"failed"`.
+
+**Never**: silently swallow exceptions, use bare `except:`, or catch `BaseException`.
+
+---
+
+## Async
+
+### Rules for the refactor
+
+1. **Don't declare `async def` unless the function awaits something.** Several service modules still declare `async def` without awaiting -- these should be migrated to sync functions with `asyncio.to_thread()` at the route layer, or to real async SQLAlchemy.
+2. **CPU-bound work** (audio processing, numpy operations) goes through `asyncio.to_thread()`:
+   ```python
+   audio, sr = await asyncio.to_thread(load_audio, source_path)
+   ```
+3. **GPU-bound TTS inference** is serialized through the generation queue (`services/task_queue.py`). Never call a backend's `generate()` directly from a route handler.
+4. **Fire-and-forget tasks**: use `asyncio.create_task()` and track the task reference to prevent garbage collection:
+   ```python
+   task = asyncio.create_task(some_coro())
+   _background_tasks.add(task)
+   task.add_done_callback(_background_tasks.discard)
+   ```
+
+---
+
+## Logging
+
+Use the `logging` module. Not `print()`.
+
+```python
+import logging
+
+logger = logging.getLogger(__name__)
+
+logger.info("Loading model %s on %s", model_name, device)
+logger.warning("Cache miss for %s, downloading", repo_id)
+logger.exception("Generation %s failed")  # logs traceback automatically
+```
+
+**Rules:**
+- Use `%s`-style placeholders in log calls (not f-strings). This avoids formatting the string if the log level is filtered out.
+- Use `logger.exception()` inside `except` blocks -- it captures the traceback.
+- Logger name should be `__name__` (yields `backend.utils.audio`, etc.).
+- Existing `print()` calls should be migrated to logging as files are touched during the refactor.
+
+---
+
+## Constants
+
+- Define at **module level** in the file where they're primarily used.
+- Use `UPPER_SNAKE_CASE`.
+- Shared/cross-cutting constants (sample rates, file size limits, CORS origins) go in `backend/config.py` after Phase 6 consolidation.
+- Magic numbers in function bodies should be extracted to named constants:
+  ```python
+  # No
+  if len(audio) > 24000 * 60 * 10:
+
+  # Yes
+  MAX_AUDIO_DURATION_SAMPLES = SAMPLE_RATE * 60 * 10
+  if len(audio) > MAX_AUDIO_DURATION_SAMPLES:
+  ```
+
+---
+
+## Function Signatures
+
+- **Keyword-only arguments** (after `*`) for functions with 3+ parameters, especially when several share the same type:
+  ```python
+  def is_model_cached(
+      hf_repo: str,
+      *,
+      weight_extensions: tuple[str, ...] = (".safetensors", ".bin"),
+      required_files: list[str] | None = None,
+  ) -> bool:
+  ```
+- Parameters on **separate lines** when the signature exceeds ~100 characters or has 3+ params.
+- **Trailing comma** after the last parameter in multi-line signatures.
+- Default values inline with the parameter.
+
+---
+
+## String Formatting
+
+- **f-strings** for runtime string construction.
+- **`%s`-style** for `logging` calls (lazy evaluation).
+- **`.format()`**: avoid; f-strings are preferred.
+
+---
+
+## Testing
+
+Framework: **pytest** with `pytest-asyncio`.
+
+- Test files: `test_<module>.py` in `backend/tests/`.
+- Use `conftest.py` for shared fixtures (db sessions, test client, mock backends).
+- Group related tests in classes: `class TestProfileCRUD:`.
+- Use `@pytest.mark.asyncio` for async tests.
+- Use `@pytest.mark.parametrize` to reduce repetition.
+- Manual integration scripts stay in `tests/` but are clearly marked (filename prefix `manual_` or documented in `tests/README.md`).
+
+---
+
+## Project Layout
+
+```
+backend/
+  app.py              # FastAPI app factory, CORS, lifecycle events
+  main.py             # Entry point (imports app, runs uvicorn)
+  config.py           # Data directory paths
+  models.py           # Pydantic request/response schemas
+  server.py           # Tauri sidecar launcher, parent-pid watchdog
+  routes/             # Thin HTTP handlers (validation, delegation, response formatting)
+  services/           # Business logic, CRUD, orchestration
+  backends/           # TTS/STT engine implementations
+  database/           # ORM models, session management, migrations, seeds
+  utils/              # Shared utilities (audio, effects, caching, progress)
+  tests/              # pytest suite
+```
+
+---
+
+## Ruff Adoption
+
+`pyproject.toml` configures ruff for linting and formatting. Run:
+
+```bash
+# Lint (check)
+ruff check backend/
+
+# Lint (auto-fix)
+ruff check backend/ --fix
+
+# Format
+ruff format backend/
+```
+
+Introduce ruff fixes file-by-file as you touch them. Don't run `--fix` across the entire codebase in one shot -- that creates unreviewable diffs.

backend/__init__.py

@@ -1,3 +1,3 @@
 # Backend package
 
-__version__ = "0.2.4"
+__version__ = "0.2.3"

backend/app.py

@@ -0,0 +1,253 @@
+"""FastAPI application factory, middleware, and lifecycle events."""
+
+import asyncio
+import logging
+import os
+import sys
+from pathlib import Path
+
+
+class ColoredFormatter(logging.Formatter):
+    """Custom formatter to add colors matching uvicorn's style."""
+
+    COLORS = {
+        "DEBUG": "\033[36m",  # Cyan
+        "INFO": "\033[32m",  # Green
+        "WARNING": "\033[33m",  # Yellow
+        "ERROR": "\033[31m",  # Red
+        "CRITICAL": "\033[35m",  # Magenta
+    }
+    RESET = "\033[0m"
+
+    def format(self, record):
+        log_color = self.COLORS.get(record.levelname, self.RESET)
+        record.levelname = f"{log_color}{record.levelname}{self.RESET}"
+        return super().format(record)
+
+
+# Configure logging to match uvicorn's format with colors
+handler = logging.StreamHandler(sys.stderr)
+handler.setFormatter(ColoredFormatter("%(levelname)s:     %(message)s"))
+logging.basicConfig(
+    level=logging.INFO,
+    handlers=[handler],
+)
+
+logger = logging.getLogger(__name__)
+
+# AMD GPU environment variables must be set before torch import
+if not os.environ.get("HSA_OVERRIDE_GFX_VERSION"):
+    os.environ["HSA_OVERRIDE_GFX_VERSION"] = "10.3.0"
+if not os.environ.get("MIOPEN_LOG_LEVEL"):
+    os.environ["MIOPEN_LOG_LEVEL"] = "4"
+
+import torch
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+from urllib.parse import quote
+
+from . import __version__, config, database
+from .services import tts, transcribe
+from .database import get_db
+from .utils.platform_detect import get_backend_type
+from .utils.progress import get_progress_manager
+from .services.task_queue import create_background_task, init_queue
+from .routes import register_routers
+
+
+def safe_content_disposition(disposition_type: str, filename: str) -> str:
+    """Build a Content-Disposition header safe for non-ASCII filenames.
+
+    Uses RFC 5987 ``filename*`` parameter so browsers can decode UTF-8
+    filenames while the ``filename`` fallback stays ASCII-only.
+    """
+    ascii_name = "".join(c for c in filename if c.isascii() and (c.isalnum() or c in " -_.")).strip() or "download"
+    utf8_name = quote(filename, safe="")
+    return f"{disposition_type}; filename=\"{ascii_name}\"; filename*=UTF-8''{utf8_name}"
+
+
+def create_app() -> FastAPI:
+    """Create and configure the FastAPI application."""
+    application = FastAPI(
+        title="voicebox API",
+        description="Production-quality Qwen3-TTS voice cloning API",
+        version=__version__,
+    )
+
+    _configure_cors(application)
+    register_routers(application)
+    _register_lifecycle(application)
+    _mount_frontend(application)
+
+    return application
+
+
+def _configure_cors(application: FastAPI) -> None:
+    """Set up CORS middleware with local-first defaults."""
+    default_origins = [
+        "http://localhost:5173",  # Vite dev server
+        "http://127.0.0.1:5173",
+        "http://localhost:17493",
+        "http://127.0.0.1:17493",
+        "tauri://localhost",  # Tauri webview (macOS)
+        "https://tauri.localhost",  # Tauri webview (Windows/Linux)
+        "http://tauri.localhost",  # Tauri webview (Windows, some builds)
+    ]
+    env_origins = os.environ.get("VOICEBOX_CORS_ORIGINS", "")
+    all_origins = default_origins + [o.strip() for o in env_origins.split(",") if o.strip()]
+
+    application.add_middleware(
+        CORSMiddleware,
+        allow_origins=all_origins,
+        allow_credentials=True,
+        allow_methods=["*"],
+        allow_headers=["*"],
+    )
+
+
+def _mount_frontend(application: FastAPI) -> None:
+    """Serve the built web frontend when present (Docker / web deployment).
+
+    The Dockerfile copies the Vite build output to ``/app/frontend/``.  When
+    that directory exists we mount static assets and add a catch-all route so
+    the React SPA handles client-side routing.  In dev or API-only mode the
+    directory is absent and this function is a no-op.
+    """
+    frontend_dir = Path(__file__).resolve().parent.parent / "frontend"
+    if not frontend_dir.is_dir():
+        return
+
+    from fastapi.staticfiles import StaticFiles
+    from fastapi.responses import FileResponse
+
+    # Mount hashed assets (JS, CSS, images) that Vite places under /assets
+    assets_dir = frontend_dir / "assets"
+    if assets_dir.is_dir():
+        application.mount(
+            "/assets",
+            StaticFiles(directory=str(assets_dir)),
+            name="frontend-assets",
+        )
+
+    # SPA catch-all: serve files if they exist, otherwise index.html for
+    # client-side routes like /voices, /stories, /models, etc.
+    @application.get("/{full_path:path}")
+    async def serve_spa(full_path: str):
+        file_path = (frontend_dir / full_path).resolve()
+        # Guard against path traversal — only serve files inside frontend_dir
+        if full_path and file_path.is_file() and str(file_path).startswith(str(frontend_dir)):
+            return FileResponse(file_path)
+        return FileResponse(frontend_dir / "index.html", media_type="text/html")
+
+    logger.info("Frontend: serving SPA from %s", frontend_dir)
+
+
+def _get_gpu_status() -> str:
+    """Return a human-readable string describing GPU availability."""
+    backend_type = get_backend_type()
+    if torch.cuda.is_available():
+        device_name = torch.cuda.get_device_name(0)
+        is_rocm = hasattr(torch.version, "hip") and torch.version.hip is not None
+        if is_rocm:
+            return f"ROCm ({device_name})"
+        return f"CUDA ({device_name})"
+    elif hasattr(torch.backends, "mps") and torch.backends.mps.is_available():
+        return "MPS (Apple Silicon)"
+    elif backend_type == "mlx":
+        return "Metal (Apple Silicon via MLX)"
+    return "None (CPU only)"
+
+
+def _register_lifecycle(application: FastAPI) -> None:
+    """Attach startup and shutdown event handlers."""
+
+    @application.on_event("startup")
+    async def startup_event():
+        import platform
+        import sys
+
+        logger.info("Voicebox v%s starting up", __version__)
+        logger.info(
+            "Python %s on %s %s (%s)",
+            sys.version.split()[0],
+            platform.system(),
+            platform.release(),
+            platform.machine(),
+        )
+
+        database.init_db()
+
+        from .database.session import _db_path
+
+        logger.info("Database: %s", _db_path)
+        logger.info("Data directory: %s", config.get_data_dir())
+
+        init_queue()
+
+        # Mark stale "generating" records as failed -- leftovers from a killed process
+        from sqlalchemy import text as sa_text
+
+        db = next(get_db())
+        try:
+            result = db.execute(
+                sa_text(
+                    "UPDATE generations SET status = 'failed', "
+                    "error = 'Server was shut down during generation' "
+                    "WHERE status IN ('generating', 'loading_model')"
+                )
+            )
+            if result.rowcount > 0:
+                logger.info("Marked %d stale generation(s) as failed", result.rowcount)
+
+            from .database import VoiceProfile as DBVoiceProfile, Generation as DBGeneration
+
+            profile_count = db.query(DBVoiceProfile).count()
+            generation_count = db.query(DBGeneration).count()
+            logger.info("Profiles: %d, Generations: %d", profile_count, generation_count)
+
+            db.commit()
+        except Exception as e:
+            db.rollback()
+            logger.warning("Could not clean up stale generations: %s", e)
+        finally:
+            db.close()
+
+        backend_type = get_backend_type()
+        logger.info("Backend: %s", backend_type.upper())
+        logger.info("GPU: %s", _get_gpu_status())
+
+        from .services.cuda import check_and_update_cuda_binary
+
+        create_background_task(check_and_update_cuda_binary())
+
+        try:
+            progress_manager = get_progress_manager()
+            progress_manager._set_main_loop(asyncio.get_running_loop())
+        except Exception as e:
+            logger.warning("Could not initialize progress manager event loop: %s", e)
+
+        try:
+            from huggingface_hub import constants as hf_constants
+
+            cache_dir = Path(hf_constants.HF_HUB_CACHE)
+            cache_dir.mkdir(parents=True, exist_ok=True)
+            logger.info("Model cache: %s", cache_dir)
+        except Exception as e:
+            logger.warning("Could not create HuggingFace cache directory: %s", e)
+
+        logger.info("Ready")
+
+    @application.on_event("shutdown")
+    async def shutdown_event():
+        logger.info("Voicebox server shutting down...")
+        try:
+            tts.unload_tts_model()
+        except Exception:
+            logger.exception("Failed to unload TTS model")
+        try:
+            transcribe.unload_whisper_model()
+        except Exception:
+            logger.exception("Failed to unload Whisper model")
+
+
+app = create_app()

backend/backends/__init__.py

@@ -1,25 +1,66 @@
 """
 Backend abstraction layer for TTS and STT.
 
-Provides a unified interface for MLX and PyTorch backends.
+Provides a unified interface for MLX and PyTorch backends,
+and a model config registry that eliminates per-engine dispatch maps.
 """
 
 import threading
+from dataclasses import dataclass, field
 from typing import Protocol, Optional, Tuple, List
 from typing_extensions import runtime_checkable
 import numpy as np
 
-from ..platform_detect import get_backend_type
+from ..utils.platform_detect import get_backend_type
+
+LANGUAGE_CODE_TO_NAME = {
+    "zh": "chinese",
+    "en": "english",
+    "ja": "japanese",
+    "ko": "korean",
+    "de": "german",
+    "fr": "french",
+    "ru": "russian",
+    "pt": "portuguese",
+    "es": "spanish",
+    "it": "italian",
+}
+
+WHISPER_HF_REPOS = {
+    "base": "openai/whisper-base",
+    "small": "openai/whisper-small",
+    "medium": "openai/whisper-medium",
+    "large": "openai/whisper-large-v3",
+    "turbo": "openai/whisper-large-v3-turbo",
+}
+
+
+@dataclass
+class ModelConfig:
+    """Declarative config for a downloadable model variant."""
+
+    model_name: str  # e.g. "luxtts", "chatterbox-tts"
+    display_name: str  # e.g. "LuxTTS (Fast, CPU-friendly)"
+    engine: str  # e.g. "luxtts", "chatterbox"
+    hf_repo_id: str  # e.g. "YatharthS/LuxTTS"
+    model_size: str = "default"
+    size_mb: int = 0
+    needs_trim: bool = False
+    supports_instruct: bool = False
+    languages: list[str] = field(default_factory=lambda: ["en"])
 
 
 @runtime_checkable
 class TTSBackend(Protocol):
     """Protocol for TTS backend implementations."""
-    
+
+    # Each backend class should define MODEL_CONFIGS as a class variable:
+    # MODEL_CONFIGS: list[ModelConfig]
+
     async def load_model(self, model_size: str) -> None:
         """Load TTS model."""
         ...
-    
+
     async def create_voice_prompt(
         self,
         audio_path: str,
@@ -28,12 +69,12 @@ class TTSBackend(Protocol):
     ) -> Tuple[dict, bool]:
         """
         Create voice prompt from reference audio.
-        
+
         Returns:
             Tuple of (voice_prompt_dict, was_cached)
         """
         ...
-    
+
     async def combine_voice_prompts(
         self,
         audio_paths: List[str],
@@ -41,12 +82,12 @@ class TTSBackend(Protocol):
     ) -> Tuple[np.ndarray, str]:
         """
         Combine multiple voice prompts.
-        
+
         Returns:
             Tuple of (combined_audio_array, combined_text)
         """
         ...
-    
+
     async def generate(
         self,
         text: str,
@@ -57,24 +98,24 @@ class TTSBackend(Protocol):
     ) -> Tuple[np.ndarray, int]:
         """
         Generate audio from text.
-        
+
         Returns:
             Tuple of (audio_array, sample_rate)
         """
         ...
-    
+
     def unload_model(self) -> None:
         """Unload model to free memory."""
         ...
-    
+
     def is_loaded(self) -> bool:
         """Check if model is loaded."""
         ...
-    
+
     def _get_model_path(self, model_size: str) -> str:
         """
         Get model path for a given size.
-        
+
         Returns:
             Model path or HuggingFace Hub ID
         """
@@ -84,28 +125,29 @@ class TTSBackend(Protocol):
 @runtime_checkable
 class STTBackend(Protocol):
     """Protocol for STT (Speech-to-Text) backend implementations."""
-    
+
     async def load_model(self, model_size: str) -> None:
         """Load STT model."""
         ...
-    
+
     async def transcribe(
         self,
         audio_path: str,
         language: Optional[str] = None,
+        model_size: Optional[str] = None,
     ) -> str:
         """
         Transcribe audio to text.
-        
+
         Returns:
             Transcribed text
         """
         ...
-    
+
     def unload_model(self) -> None:
         """Unload model to free memory."""
         ...
-    
+
     def is_loaded(self) -> bool:
         """Check if model is loaded."""
         ...
@@ -117,7 +159,8 @@ _tts_backends: dict[str, TTSBackend] = {}
 _tts_backends_lock = threading.Lock()
 _stt_backend: Optional[STTBackend] = None
 
-# Supported TTS engines
+# Supported TTS engines — keyed by engine name, value is the backend class import path.
+# The factory function uses this for the if/elif chain; the model configs live on the backend classes.
 TTS_ENGINES = {
     "qwen": "Qwen TTS",
     "luxtts": "LuxTTS",
@@ -126,10 +169,277 @@ TTS_ENGINES = {
 }
 
 
+def _get_qwen_model_configs() -> list[ModelConfig]:
+    """Return Qwen model configs with backend-aware HF repo IDs."""
+    backend_type = get_backend_type()
+    if backend_type == "mlx":
+        repo_1_7b = "mlx-community/Qwen3-TTS-12Hz-1.7B-Base-bf16"
+        repo_0_6b = "mlx-community/Qwen3-TTS-12Hz-1.7B-Base-bf16"  # 0.6B not available in MLX, falls back
+    else:
+        repo_1_7b = "Qwen/Qwen3-TTS-12Hz-1.7B-Base"
+        repo_0_6b = "Qwen/Qwen3-TTS-12Hz-0.6B-Base"
+
+    return [
+        ModelConfig(
+            model_name="qwen-tts-1.7B",
+            display_name="Qwen TTS 1.7B",
+            engine="qwen",
+            hf_repo_id=repo_1_7b,
+            model_size="1.7B",
+            size_mb=3500,
+            supports_instruct=False,  # Base model drops instruct silently
+            languages=["zh", "en", "ja", "ko", "de", "fr", "ru", "pt", "es", "it"],
+        ),
+        ModelConfig(
+            model_name="qwen-tts-0.6B",
+            display_name="Qwen TTS 0.6B",
+            engine="qwen",
+            hf_repo_id=repo_0_6b,
+            model_size="0.6B",
+            size_mb=1200,
+            supports_instruct=False,
+            languages=["zh", "en", "ja", "ko", "de", "fr", "ru", "pt", "es", "it"],
+        ),
+    ]
+
+
+def _get_non_qwen_tts_configs() -> list[ModelConfig]:
+    """Return model configs for non-Qwen TTS engines.
+
+    These are static — no backend-type branching needed.
+    """
+    return [
+        ModelConfig(
+            model_name="luxtts",
+            display_name="LuxTTS (Fast, CPU-friendly)",
+            engine="luxtts",
+            hf_repo_id="YatharthS/LuxTTS",
+            size_mb=300,
+            languages=["en"],
+        ),
+        ModelConfig(
+            model_name="chatterbox-tts",
+            display_name="Chatterbox TTS (Multilingual)",
+            engine="chatterbox",
+            hf_repo_id="ResembleAI/chatterbox",
+            size_mb=3200,
+            needs_trim=True,
+            languages=[
+                "zh",
+                "en",
+                "ja",
+                "ko",
+                "de",
+                "fr",
+                "ru",
+                "pt",
+                "es",
+                "it",
+                "he",
+                "ar",
+                "da",
+                "el",
+                "fi",
+                "hi",
+                "ms",
+                "nl",
+                "no",
+                "pl",
+                "sv",
+                "sw",
+                "tr",
+            ],
+        ),
+        ModelConfig(
+            model_name="chatterbox-turbo",
+            display_name="Chatterbox Turbo (English, Tags)",
+            engine="chatterbox_turbo",
+            hf_repo_id="ResembleAI/chatterbox-turbo",
+            size_mb=1500,
+            needs_trim=True,
+            languages=["en"],
+        ),
+    ]
+
+
+def _get_whisper_configs() -> list[ModelConfig]:
+    """Return Whisper STT model configs."""
+    return [
+        ModelConfig(
+            model_name="whisper-base",
+            display_name="Whisper Base",
+            engine="whisper",
+            hf_repo_id="openai/whisper-base",
+            model_size="base",
+        ),
+        ModelConfig(
+            model_name="whisper-small",
+            display_name="Whisper Small",
+            engine="whisper",
+            hf_repo_id="openai/whisper-small",
+            model_size="small",
+        ),
+        ModelConfig(
+            model_name="whisper-medium",
+            display_name="Whisper Medium",
+            engine="whisper",
+            hf_repo_id="openai/whisper-medium",
+            model_size="medium",
+        ),
+        ModelConfig(
+            model_name="whisper-large",
+            display_name="Whisper Large",
+            engine="whisper",
+            hf_repo_id="openai/whisper-large-v3",
+            model_size="large",
+        ),
+        ModelConfig(
+            model_name="whisper-turbo",
+            display_name="Whisper Turbo",
+            engine="whisper",
+            hf_repo_id="openai/whisper-large-v3-turbo",
+            model_size="turbo",
+        ),
+    ]
+
+
+def get_all_model_configs() -> list[ModelConfig]:
+    """Return the full list of model configs (TTS + STT)."""
+    return _get_qwen_model_configs() + _get_non_qwen_tts_configs() + _get_whisper_configs()
+
+
+def get_tts_model_configs() -> list[ModelConfig]:
+    """Return only TTS model configs."""
+    return _get_qwen_model_configs() + _get_non_qwen_tts_configs()
+
+
+# Lookup helpers — these replace the if/elif chains in main.py
+
+
+def get_model_config(model_name: str) -> Optional[ModelConfig]:
+    """Look up a model config by model_name."""
+    for cfg in get_all_model_configs():
+        if cfg.model_name == model_name:
+            return cfg
+    return None
+
+
+def engine_needs_trim(engine: str) -> bool:
+    """Whether this engine's output should be run through trim_tts_output."""
+    for cfg in get_tts_model_configs():
+        if cfg.engine == engine:
+            return cfg.needs_trim
+    return False
+
+
+def engine_has_model_sizes(engine: str) -> bool:
+    """Whether this engine supports multiple model sizes (only Qwen currently)."""
+    configs = [c for c in get_tts_model_configs() if c.engine == engine]
+    return len(configs) > 1
+
+
+async def load_engine_model(engine: str, model_size: str = "default") -> None:
+    """Load a model for the given engine, handling the Qwen model_size special case."""
+    backend = get_tts_backend_for_engine(engine)
+    if engine == "qwen":
+        await backend.load_model_async(model_size)
+    else:
+        await backend.load_model()
+
+
+async def ensure_model_cached_or_raise(engine: str, model_size: str = "default") -> None:
+    """Check if a model is cached, raise HTTPException if not. Used by streaming endpoint."""
+    from fastapi import HTTPException
+
+    backend = get_tts_backend_for_engine(engine)
+    cfg = None
+    for c in get_tts_model_configs():
+        if c.engine == engine and c.model_size == model_size:
+            cfg = c
+            break
+
+    if engine == "qwen":
+        if not backend._is_model_cached(model_size):
+            raise HTTPException(
+                status_code=400,
+                detail=f"Model {model_size} is not downloaded yet. Use /generate to trigger a download.",
+            )
+    else:
+        if not backend._is_model_cached():
+            display = cfg.display_name if cfg else engine
+            raise HTTPException(
+                status_code=400,
+                detail=f"{display} model is not downloaded yet. Use /generate to trigger a download.",
+            )
+
+
+def unload_model_by_config(config: ModelConfig) -> bool:
+    """Unload a model given its config. Returns True if it was loaded, False otherwise."""
+    from . import get_tts_backend_for_engine
+    from ..services import tts, transcribe
+
+    if config.engine == "whisper":
+        whisper_model = transcribe.get_whisper_model()
+        if whisper_model.is_loaded() and whisper_model.model_size == config.model_size:
+            transcribe.unload_whisper_model()
+            return True
+        return False
+
+    if config.engine == "qwen":
+        tts_model = tts.get_tts_model()
+        loaded_size = getattr(tts_model, "_current_model_size", None) or getattr(tts_model, "model_size", None)
+        if tts_model.is_loaded() and loaded_size == config.model_size:
+            tts.unload_tts_model()
+            return True
+        return False
+
+    # All other TTS engines
+    backend = get_tts_backend_for_engine(config.engine)
+    if backend.is_loaded():
+        backend.unload_model()
+        return True
+    return False
+
+
+def check_model_loaded(config: ModelConfig) -> bool:
+    """Check if a model is currently loaded."""
+    from . import get_tts_backend_for_engine
+    from ..services import tts, transcribe
+
+    try:
+        if config.engine == "whisper":
+            whisper_model = transcribe.get_whisper_model()
+            return whisper_model.is_loaded() and getattr(whisper_model, "model_size", None) == config.model_size
+
+        if config.engine == "qwen":
+            tts_model = tts.get_tts_model()
+            loaded_size = getattr(tts_model, "_current_model_size", None) or getattr(tts_model, "model_size", None)
+            return tts_model.is_loaded() and loaded_size == config.model_size
+
+        backend = get_tts_backend_for_engine(config.engine)
+        return backend.is_loaded()
+    except Exception:
+        return False
+
+
+def get_model_load_func(config: ModelConfig):
+    """Return a callable that loads/downloads the model."""
+    from . import get_tts_backend_for_engine
+    from ..services import tts, transcribe
+
+    if config.engine == "whisper":
+        return lambda: transcribe.get_whisper_model().load_model(config.model_size)
+
+    if config.engine == "qwen":
+        return lambda: tts.get_tts_model().load_model(config.model_size)
+
+    return lambda: get_tts_backend_for_engine(config.engine).load_model()
+
+
 def get_tts_backend() -> TTSBackend:
     """
     Get or create the default (Qwen) TTS backend instance based on platform.
-    
+
     Returns:
         TTS backend instance (MLX or PyTorch)
     """
@@ -139,45 +449,50 @@ def get_tts_backend() -> TTSBackend:
 def get_tts_backend_for_engine(engine: str) -> TTSBackend:
     """
     Get or create a TTS backend for the given engine.
-    
+
     Args:
-        engine: Engine name ("qwen" or "luxtts")
+        engine: Engine name (e.g. "qwen", "luxtts", "chatterbox", "chatterbox_turbo")
-    
+
     Returns:
         TTS backend instance
     """
     global _tts_backends
-    
+
     # Fast path: check without lock
     if engine in _tts_backends:
         return _tts_backends[engine]
-    
+
     # Slow path: create with lock to avoid duplicate instantiation
     with _tts_backends_lock:
         # Double-check after acquiring lock
         if engine in _tts_backends:
             return _tts_backends[engine]
-        
+
         if engine == "qwen":
             backend_type = get_backend_type()
             if backend_type == "mlx":
                 from .mlx_backend import MLXTTSBackend
+
                 backend = MLXTTSBackend()
             else:
                 from .pytorch_backend import PyTorchTTSBackend
+
                 backend = PyTorchTTSBackend()
         elif engine == "luxtts":
             from .luxtts_backend import LuxTTSBackend
+
             backend = LuxTTSBackend()
         elif engine == "chatterbox":
             from .chatterbox_backend import ChatterboxTTSBackend
+
             backend = ChatterboxTTSBackend()
         elif engine == "chatterbox_turbo":
             from .chatterbox_turbo_backend import ChatterboxTurboTTSBackend
+
             backend = ChatterboxTurboTTSBackend()
         else:
             raise ValueError(f"Unknown TTS engine: {engine}. Supported: {list(TTS_ENGINES.keys())}")
-        
+
         _tts_backends[engine] = backend
         return backend
 
@@ -185,22 +500,24 @@ def get_tts_backend_for_engine(engine: str) -> TTSBackend:
 def get_stt_backend() -> STTBackend:
     """
     Get or create STT backend instance based on platform.
-    
+
     Returns:
         STT backend instance (MLX or PyTorch)
     """
     global _stt_backend
-    
+
     if _stt_backend is None:
         backend_type = get_backend_type()
-        
+
         if backend_type == "mlx":
             from .mlx_backend import MLXSTTBackend
+
             _stt_backend = MLXSTTBackend()
         else:
             from .pytorch_backend import PyTorchSTTBackend
+
             _stt_backend = PyTorchSTTBackend()
-    
+
     return _stt_backend
 
 

backend/backends/base.py

@@ -0,0 +1,258 @@
+"""
+Shared utilities for TTS/STT backend implementations.
+
+Eliminates duplication of cache checking, device detection,
+voice prompt combination, and model loading progress tracking.
+"""
+
+import logging
+import platform
+from contextlib import contextmanager
+from pathlib import Path
+from typing import Callable, List, Optional, Tuple
+
+import numpy as np
+
+from ..utils.audio import normalize_audio, load_audio
+from ..utils.progress import get_progress_manager
+from ..utils.hf_progress import HFProgressTracker, create_hf_progress_callback
+from ..utils.tasks import get_task_manager
+
+logger = logging.getLogger(__name__)
+
+
+def is_model_cached(
+    hf_repo: str,
+    *,
+    weight_extensions: tuple[str, ...] = (".safetensors", ".bin"),
+    required_files: Optional[list[str]] = None,
+) -> bool:
+    """
+    Check if a HuggingFace model is fully cached locally.
+
+    Args:
+        hf_repo: HuggingFace repo ID (e.g. "Qwen/Qwen3-TTS-12Hz-1.7B-Base")
+        weight_extensions: File extensions that count as model weights.
+        required_files: If set, check that these specific filenames exist
+                        in snapshots instead of checking by extension.
+
+    Returns:
+        True if model is fully cached, False if missing or incomplete.
+    """
+    try:
+        from huggingface_hub import constants as hf_constants
+
+        repo_cache = Path(hf_constants.HF_HUB_CACHE) / ("models--" + hf_repo.replace("/", "--"))
+
+        if not repo_cache.exists():
+            return False
+
+        # Incomplete blobs mean a download is still in progress
+        blobs_dir = repo_cache / "blobs"
+        if blobs_dir.exists() and any(blobs_dir.glob("*.incomplete")):
+            logger.debug(f"Found .incomplete files for {hf_repo}")
+            return False
+
+        snapshots_dir = repo_cache / "snapshots"
+        if not snapshots_dir.exists():
+            return False
+
+        if required_files:
+            # Check that every required filename exists somewhere in snapshots
+            for fname in required_files:
+                if not any(snapshots_dir.rglob(fname)):
+                    return False
+            return True
+
+        # Check that at least one weight file exists
+        for ext in weight_extensions:
+            if any(snapshots_dir.rglob(f"*{ext}")):
+                return True
+
+        logger.debug(f"No model weights found for {hf_repo}")
+        return False
+
+    except Exception as e:
+        logger.warning(f"Error checking cache for {hf_repo}: {e}")
+        return False
+
+
+def get_torch_device(
+    *,
+    allow_xpu: bool = False,
+    allow_directml: bool = False,
+    allow_mps: bool = False,
+    force_cpu_on_mac: bool = False,
+) -> str:
+    """
+    Detect the best available torch device.
+
+    Args:
+        allow_xpu: Check for Intel XPU (IPEX) support.
+        allow_directml: Check for DirectML (Windows) support.
+        allow_mps: Allow MPS (Apple Silicon). If False, MPS falls back to CPU.
+        force_cpu_on_mac: Force CPU on macOS regardless of GPU availability.
+    """
+    if force_cpu_on_mac and platform.system() == "Darwin":
+        return "cpu"
+
+    import torch
+
+    if torch.cuda.is_available():
+        return "cuda"
+
+    if allow_xpu:
+        try:
+            import intel_extension_for_pytorch  # noqa: F401
+
+            if hasattr(torch, "xpu") and torch.xpu.is_available():
+                return "xpu"
+        except ImportError:
+            pass
+
+    if allow_directml:
+        try:
+            import torch_directml
+
+            if torch_directml.device_count() > 0:
+                return torch_directml.device(0)
+        except ImportError:
+            pass
+
+    if allow_mps:
+        if hasattr(torch.backends, "mps") and torch.backends.mps.is_available():
+            return "mps"
+
+    return "cpu"
+
+
+async def combine_voice_prompts(
+    audio_paths: List[str],
+    reference_texts: List[str],
+    *,
+    sample_rate: Optional[int] = None,
+) -> Tuple[np.ndarray, str]:
+    """
+    Combine multiple reference audio samples into one.
+
+    Loads each audio file, normalizes, concatenates, and joins texts.
+
+    Args:
+        audio_paths: Paths to reference audio files.
+        reference_texts: Corresponding transcripts.
+        sample_rate: If set, resample audio to this rate during loading.
+    """
+    combined_audio = []
+
+    for path in audio_paths:
+        kwargs = {"sample_rate": sample_rate} if sample_rate else {}
+        audio, _sr = load_audio(path, **kwargs)
+        audio = normalize_audio(audio)
+        combined_audio.append(audio)
+
+    mixed = np.concatenate(combined_audio)
+    mixed = normalize_audio(mixed)
+    combined_text = " ".join(reference_texts)
+
+    return mixed, combined_text
+
+
+@contextmanager
+def model_load_progress(
+    model_name: str,
+    is_cached: bool,
+    filter_non_downloads: Optional[bool] = None,
+):
+    """
+    Context manager for model loading with HF download progress tracking.
+
+    Handles the tqdm patching, progress_manager/task_manager lifecycle,
+    and error reporting that every backend duplicates.
+
+    Args:
+        model_name: Progress tracking key (e.g. "qwen-tts-1.7B", "whisper-base").
+        is_cached: Whether the model is already downloaded.
+        filter_non_downloads: Whether to filter non-download tqdm bars.
+                              Defaults to `is_cached`.
+
+    Yields:
+        The tracker context (already entered). The caller loads the model
+        inside the `with` block. The tqdm patch is torn down on exit.
+
+    Usage:
+        with model_load_progress("qwen-tts-1.7B", is_cached) as ctx:
+            self.model = SomeModel.from_pretrained(...)
+    """
+    if filter_non_downloads is None:
+        filter_non_downloads = is_cached
+
+    progress_manager = get_progress_manager()
+    task_manager = get_task_manager()
+
+    progress_callback = create_hf_progress_callback(model_name, progress_manager)
+    tracker = HFProgressTracker(progress_callback, filter_non_downloads=filter_non_downloads)
+
+    tracker_context = tracker.patch_download()
+    tracker_context.__enter__()
+
+    if not is_cached:
+        task_manager.start_download(model_name)
+        progress_manager.update_progress(
+            model_name=model_name,
+            current=0,
+            total=0,
+            filename="Connecting to HuggingFace...",
+            status="downloading",
+        )
+
+    try:
+        yield tracker_context
+    except Exception as e:
+        # Report error to both managers
+        progress_manager.mark_error(model_name, str(e))
+        task_manager.error_download(model_name, str(e))
+        raise
+    else:
+        # Only mark complete if we were tracking a download
+        if not is_cached:
+            progress_manager.mark_complete(model_name)
+            task_manager.complete_download(model_name)
+    finally:
+        tracker_context.__exit__(None, None, None)
+
+
+def patch_chatterbox_f32(model) -> None:
+    """
+    Patch float64 -> float32 dtype mismatches in upstream chatterbox.
+
+    librosa.load returns float64 numpy arrays. Multiple upstream code paths
+    convert these to torch tensors via torch.from_numpy() without casting,
+    then matmul against float32 model weights. This patches the two known
+    entry points:
+
+    1. S3Tokenizer.log_mel_spectrogram — audio tensor hits _mel_filters (f32)
+    2. VoiceEncoder.forward — float64 mel spectrograms hit LSTM weights (f32)
+    """
+    import types
+
+    # Patch S3Tokenizer
+    _tokzr = model.s3gen.tokenizer
+    _orig_log_mel = _tokzr.log_mel_spectrogram.__func__
+
+    def _f32_log_mel(self_tokzr, audio, padding=0):
+        import torch as _torch
+
+        if _torch.is_tensor(audio):
+            audio = audio.float()
+        return _orig_log_mel(self_tokzr, audio, padding)
+
+    _tokzr.log_mel_spectrogram = types.MethodType(_f32_log_mel, _tokzr)
+
+    # Patch VoiceEncoder
+    _ve = model.ve
+    _orig_ve_forward = _ve.forward.__func__
+
+    def _f32_ve_forward(self_ve, mels):
+        return _orig_ve_forward(self_ve, mels.float())
+
+    _ve.forward = types.MethodType(_f32_ve_forward, _ve)

backend/backends/chatterbox_backend.py

@@ -8,7 +8,6 @@ on macOS due to known MPS tensor issues.
 
 import asyncio
 import logging
-import platform
 import threading
 from pathlib import Path
 from typing import ClassVar, List, Optional, Tuple
@@ -16,9 +15,13 @@ from typing import ClassVar, List, Optional, Tuple
 import numpy as np
 
 from . import TTSBackend
-from ..utils.audio import normalize_audio, load_audio
+from .base import (
-from ..utils.progress import get_progress_manager
+    is_model_cached,
-from ..utils.tasks import get_task_manager
+    get_torch_device,
+    combine_voice_prompts as _combine_voice_prompts,
+    model_load_progress,
+    patch_chatterbox_f32,
+)
 
 logger = logging.getLogger(__name__)
 
@@ -45,17 +48,7 @@ class ChatterboxTTSBackend:
         self._model_load_lock = asyncio.Lock()
 
     def _get_device(self) -> str:
-        """Get the best available device. Forces CPU on macOS (MPS issue)."""
+        return get_torch_device(force_cpu_on_mac=True)
-        if platform.system() == "Darwin":
-            return "cpu"
-        try:
-            import torch
-
-            if torch.cuda.is_available():
-                return "cuda"
-        except ImportError:
-            pass
-        return "cpu"
 
     def is_loaded(self) -> bool:
         return self.model is not None
@@ -64,33 +57,7 @@ class ChatterboxTTSBackend:
         return CHATTERBOX_HF_REPO
 
     def _is_model_cached(self, model_size: str = "default") -> bool:
-        """Check if the Chatterbox multilingual model is cached locally."""
+        return is_model_cached(CHATTERBOX_HF_REPO, required_files=_MTL_WEIGHT_FILES)
-        try:
-            from huggingface_hub import constants as hf_constants
-
-            repo_cache = Path(hf_constants.HF_HUB_CACHE) / (
-                "models--" + CHATTERBOX_HF_REPO.replace("/", "--")
-            )
-
-            if not repo_cache.exists():
-                return False
-
-            blobs_dir = repo_cache / "blobs"
-            if blobs_dir.exists() and any(blobs_dir.glob("*.incomplete")):
-                return False
-
-            # Check for multilingual weight files
-            snapshots_dir = repo_cache / "snapshots"
-            if snapshots_dir.exists():
-                for fname in _MTL_WEIGHT_FILES:
-                    if not any(snapshots_dir.rglob(fname)):
-                        return False
-                return True
-
-            return False
-        except Exception as e:
-            logger.warning(f"Error checking Chatterbox cache: {e}")
-            return False
 
     async def load_model(self, model_size: str = "default") -> None:
         """Load the Chatterbox multilingual model."""
@@ -103,132 +70,45 @@ class ChatterboxTTSBackend:
 
     def _load_model_sync(self):
         """Synchronous model loading."""
-        from ..utils.hf_progress import HFProgressTracker, create_hf_progress_callback
-
-        progress_manager = get_progress_manager()
-        task_manager = get_task_manager()
         model_name = "chatterbox-tts"
-
         is_cached = self._is_model_cached()
 
-        # Set up HF progress tracking (intercepts tqdm for file-level progress)
+        with model_load_progress(model_name, is_cached):
-        progress_callback = create_hf_progress_callback(model_name, progress_manager)
-        tracker = HFProgressTracker(progress_callback, filter_non_downloads=is_cached)
-        tracker_context = tracker.patch_download()
-        tracker_context.__enter__()
-
-        if not is_cached:
-            task_manager.start_download(model_name)
-            progress_manager.update_progress(
-                model_name=model_name,
-                current=0,
-                total=0,
-                filename="Connecting to HuggingFace...",
-                status="downloading",
-            )
-
-        try:
             device = self._get_device()
             self._device = device
-
             logger.info(f"Loading Chatterbox Multilingual TTS on {device}...")
 
             import torch
             from chatterbox.mtl_tts import ChatterboxMultilingualTTS
 
-            # Load into a local variable first, apply all patches, then
+            if device == "cpu":
-            # assign to self.model.  This avoids leaving a half-initialised
+                _orig_torch_load = torch.load
-            # model on self.model if any patch step raises an exception.
-            #
-            # Monkey-patch torch.load for CPU loading. The model's .pt files
-            # were saved on CUDA; from_pretrained() doesn't pass map_location
-            # so loading on CPU fails without this.
-            try:
-                if device == "cpu":
-                    _orig_torch_load = torch.load
 
-                    def _patched_load(*args, **kwargs):
+                def _patched_load(*args, **kwargs):
-                        kwargs.setdefault("map_location", "cpu")
+                    kwargs.setdefault("map_location", "cpu")
-                        return _orig_torch_load(*args, **kwargs)
+                    return _orig_torch_load(*args, **kwargs)
 
-                    with ChatterboxTTSBackend._load_lock:
+                with ChatterboxTTSBackend._load_lock:
-                        torch.load = _patched_load
+                    torch.load = _patched_load
-                        try:
+                    try:
-                            model = ChatterboxMultilingualTTS.from_pretrained(
+                        model = ChatterboxMultilingualTTS.from_pretrained(device=device)
-                                device=device,
+                    finally:
-                            )
+                        torch.load = _orig_torch_load
-                        finally:
+            else:
-                            torch.load = _orig_torch_load
+                model = ChatterboxMultilingualTTS.from_pretrained(device=device)
-                else:
-                    model = ChatterboxMultilingualTTS.from_pretrained(
-                        device=device,
-                    )
-            finally:
-                tracker_context.__exit__(None, None, None)
 
-            # Fix: transformers >= 4.36 defaults LlamaModel to sdpa attention
+            # Fix sdpa attention for output_attentions support
-            # which doesn't support output_attentions=True (needed by
-            # Chatterbox's AlignmentStreamAnalyzer). Force eager attention.
             t3_tfmr = model.t3.tfmr
-            if hasattr(t3_tfmr, "config") and hasattr(
+            if hasattr(t3_tfmr, "config") and hasattr(t3_tfmr.config, "_attn_implementation"):
-                t3_tfmr.config, "_attn_implementation"
-            ):
                 t3_tfmr.config._attn_implementation = "eager"
                 for layer in getattr(t3_tfmr, "layers", []):
                     if hasattr(layer, "self_attn"):
                         layer.self_attn._attn_implementation = "eager"
 
-            if not is_cached:
+            patch_chatterbox_f32(model)
-                progress_manager.mark_complete(model_name)
-                task_manager.complete_download(model_name)
-
-            # Patch float64 → float32 dtype mismatches in upstream chatterbox.
-            # librosa.load returns float64 numpy; multiple upstream code paths
-            # convert it to a torch tensor via torch.from_numpy() without
-            # casting, then matmul it against float32 model weights.
-            import types
-
-            # Patch S3Tokenizer (used by s3gen.tokenizer)
-            _tokzr = model.s3gen.tokenizer
-            _orig_log_mel = _tokzr.log_mel_spectrogram.__func__
-
-            def _f32_log_mel(self_tokzr, audio, padding=0):
-                import torch as _torch
-                if _torch.is_tensor(audio):
-                    audio = audio.float()
-                return _orig_log_mel(self_tokzr, audio, padding)
-
-            _tokzr.log_mel_spectrogram = types.MethodType(_f32_log_mel, _tokzr)
-
-            # Patch VoiceEncoder
-            _ve = model.ve
-            _orig_ve_forward = _ve.forward.__func__
-
-            def _f32_ve_forward(self_ve, mels):
-                return _orig_ve_forward(self_ve, mels.float())
-
-            _ve.forward = types.MethodType(_f32_ve_forward, _ve)
-
-            # All patches applied successfully — publish the model
             self.model = model
 
-            logger.info("Chatterbox Multilingual TTS loaded successfully")
+        logger.info("Chatterbox Multilingual TTS loaded successfully")
-
-        except ImportError as e:
-            logger.error(
-                "chatterbox-tts package not found. "
-                "Install with: pip install chatterbox-tts"
-            )
-            if not is_cached:
-                progress_manager.mark_error(model_name, str(e))
-                task_manager.error_download(model_name, str(e))
-            raise
-        except Exception as e:
-            logger.error(f"Failed to load Chatterbox: {e}")
-            if not is_cached:
-                progress_manager.mark_error(model_name, str(e))
-                task_manager.error_download(model_name, str(e))
-            raise
 
     def unload_model(self) -> None:
         """Unload model to free memory."""
@@ -267,17 +147,7 @@ class ChatterboxTTSBackend:
         audio_paths: List[str],
         reference_texts: List[str],
     ) -> Tuple[np.ndarray, str]:
-        """Combine multiple reference samples."""
+        return await _combine_voice_prompts(audio_paths, reference_texts)
-        combined_audio = []
-        for path in audio_paths:
-            audio, _sr = load_audio(path)
-            audio = normalize_audio(audio)
-            combined_audio.append(audio)
-
-        mixed = np.concatenate(combined_audio)
-        mixed = normalize_audio(mixed)
-        combined_text = " ".join(reference_texts)
-        return mixed, combined_text
 
     # Per-language generation defaults. Lower temp + higher cfg = clearer speech.
     _LANG_DEFAULTS: ClassVar[dict] = {

backend/backends/chatterbox_turbo_backend.py

@@ -8,7 +8,6 @@ Forces CPU on macOS due to known MPS tensor issues.
 
 import asyncio
 import logging
-import platform
 import threading
 from pathlib import Path
 from typing import ClassVar, List, Optional, Tuple
@@ -16,9 +15,13 @@ from typing import ClassVar, List, Optional, Tuple
 import numpy as np
 
 from . import TTSBackend
-from ..utils.audio import normalize_audio, load_audio
+from .base import (
-from ..utils.progress import get_progress_manager
+    is_model_cached,
-from ..utils.tasks import get_task_manager
+    get_torch_device,
+    combine_voice_prompts as _combine_voice_prompts,
+    model_load_progress,
+    patch_chatterbox_f32,
+)
 
 logger = logging.getLogger(__name__)
 
@@ -45,17 +48,7 @@ class ChatterboxTurboTTSBackend:
         self._model_load_lock = asyncio.Lock()
 
     def _get_device(self) -> str:
-        """Get the best available device. Forces CPU on macOS (MPS issue)."""
+        return get_torch_device(force_cpu_on_mac=True)
-        if platform.system() == "Darwin":
-            return "cpu"
-        try:
-            import torch
-
-            if torch.cuda.is_available():
-                return "cuda"
-        except ImportError:
-            pass
-        return "cpu"
 
     def is_loaded(self) -> bool:
         return self.model is not None
@@ -64,33 +57,7 @@ class ChatterboxTurboTTSBackend:
         return CHATTERBOX_TURBO_HF_REPO
 
     def _is_model_cached(self, model_size: str = "default") -> bool:
-        """Check if the Chatterbox Turbo model is cached locally."""
+        return is_model_cached(CHATTERBOX_TURBO_HF_REPO, required_files=_TURBO_WEIGHT_FILES)
-        try:
-            from huggingface_hub import constants as hf_constants
-
-            repo_cache = Path(hf_constants.HF_HUB_CACHE) / (
-                "models--" + CHATTERBOX_TURBO_HF_REPO.replace("/", "--")
-            )
-
-            if not repo_cache.exists():
-                return False
-
-            blobs_dir = repo_cache / "blobs"
-            if blobs_dir.exists() and any(blobs_dir.glob("*.incomplete")):
-                return False
-
-            # Check for turbo weight files
-            snapshots_dir = repo_cache / "snapshots"
-            if snapshots_dir.exists():
-                for fname in _TURBO_WEIGHT_FILES:
-                    if not any(snapshots_dir.rglob(fname)):
-                        return False
-                return True
-
-            return False
-        except Exception as e:
-            logger.warning(f"Error checking Chatterbox Turbo cache: {e}")
-            return False
 
     async def load_model(self, model_size: str = "default") -> None:
         """Load the Chatterbox Turbo model."""
@@ -103,59 +70,24 @@ class ChatterboxTurboTTSBackend:
 
     def _load_model_sync(self):
         """Synchronous model loading."""
-        from ..utils.hf_progress import HFProgressTracker, create_hf_progress_callback
-
-        progress_manager = get_progress_manager()
-        task_manager = get_task_manager()
         model_name = "chatterbox-turbo"
-
         is_cached = self._is_model_cached()
 
-        # Set up HF progress tracking (intercepts tqdm for file-level progress)
+        with model_load_progress(model_name, is_cached):
-        progress_callback = create_hf_progress_callback(model_name, progress_manager)
-        tracker = HFProgressTracker(progress_callback, filter_non_downloads=is_cached)
-        tracker_context = tracker.patch_download()
-        tracker_context.__enter__()
-
-        if not is_cached:
-            task_manager.start_download(model_name)
-            progress_manager.update_progress(
-                model_name=model_name,
-                current=0,
-                total=0,
-                filename="Connecting to HuggingFace...",
-                status="downloading",
-            )
-
-        try:
             device = self._get_device()
             self._device = device
-
             logger.info(f"Loading Chatterbox Turbo TTS on {device}...")
 
             import torch
             from huggingface_hub import snapshot_download
             from chatterbox.tts_turbo import ChatterboxTurboTTS
 
-            # Download model files ourselves so we can pass token=None
+            local_path = snapshot_download(
-            # (upstream from_pretrained passes token=True which requires
+                repo_id=CHATTERBOX_TURBO_HF_REPO,
-            # a stored HF token even though the repo is public).
+                token=None,
-            try:
+                allow_patterns=["*.safetensors", "*.json", "*.txt", "*.pt", "*.model"],
-                local_path = snapshot_download(
+            )
-                    repo_id=CHATTERBOX_TURBO_HF_REPO,
-                    token=None,
-                    allow_patterns=[
-                        "*.safetensors", "*.json", "*.txt", "*.pt", "*.model",
-                    ],
-                )
-            finally:
-                tracker_context.__exit__(None, None, None)
 
-            # Monkey-patch torch.load for CPU loading. The model's .pt files
-            # were saved on CUDA; from_local() doesn't pass map_location
-            # so loading on CPU fails without this.
-            # Load into a local var, apply patches, then publish to
-            # self.model so a failed patch doesn't leave us half-initialised.
             if device == "cpu":
                 _orig_torch_load = torch.load
 
@@ -166,73 +98,16 @@ class ChatterboxTurboTTSBackend:
                 with ChatterboxTurboTTSBackend._load_lock:
                     torch.load = _patched_load
                     try:
-                        model = ChatterboxTurboTTS.from_local(
+                        model = ChatterboxTurboTTS.from_local(local_path, device)
-                            local_path, device,
-                        )
                     finally:
                         torch.load = _orig_torch_load
             else:
-                model = ChatterboxTurboTTS.from_local(
+                model = ChatterboxTurboTTS.from_local(local_path, device)
-                    local_path, device,
-                )
 
-            if not is_cached:
+            patch_chatterbox_f32(model)
-                progress_manager.mark_complete(model_name)
-                task_manager.complete_download(model_name)
-
-            # Patch float64 → float32 dtype mismatches in upstream chatterbox.
-            # librosa.load returns float64 numpy; multiple upstream code paths
-            # convert it to a torch tensor via torch.from_numpy() without
-            # casting, then matmul it against float32 model weights.
-            # We patch the two known entry points:
-            #
-            # 1. S3Tokenizer.log_mel_spectrogram — the audio tensor from
-            #    librosa hits _mel_filters (float32) in a matmul.
-            # 2. VoiceEncoder.forward — float64 mel spectrograms hit the
-            #    float32 LSTM weights.
-            import types
-
-            # Patch S3Tokenizer (used by s3gen.tokenizer)
-            _tokzr = model.s3gen.tokenizer
-            _orig_log_mel = _tokzr.log_mel_spectrogram.__func__
-
-            def _f32_log_mel(self_tokzr, audio, padding=0):
-                import torch as _torch
-                if _torch.is_tensor(audio):
-                    audio = audio.float()
-                return _orig_log_mel(self_tokzr, audio, padding)
-
-            _tokzr.log_mel_spectrogram = types.MethodType(_f32_log_mel, _tokzr)
-
-            # Patch VoiceEncoder
-            _ve = model.ve
-            _orig_ve_forward = _ve.forward.__func__
-
-            def _f32_ve_forward(self_ve, mels):
-                return _orig_ve_forward(self_ve, mels.float())
-
-            _ve.forward = types.MethodType(_f32_ve_forward, _ve)
-
-            # Only publish after all patches succeed
             self.model = model
 
-            logger.info("Chatterbox Turbo TTS loaded successfully")
+        logger.info("Chatterbox Turbo TTS loaded successfully")
-
-        except ImportError as e:
-            logger.error(
-                "chatterbox-tts package not found. "
-                "Install with: pip install chatterbox-tts"
-            )
-            if not is_cached:
-                progress_manager.mark_error(model_name, str(e))
-                task_manager.error_download(model_name, str(e))
-            raise
-        except Exception as e:
-            logger.error(f"Failed to load Chatterbox Turbo: {e}")
-            if not is_cached:
-                progress_manager.mark_error(model_name, str(e))
-                task_manager.error_download(model_name, str(e))
-            raise
 
     def unload_model(self) -> None:
         """Unload model to free memory."""
@@ -270,17 +145,7 @@ class ChatterboxTurboTTSBackend:
         audio_paths: List[str],
         reference_texts: List[str],
     ) -> Tuple[np.ndarray, str]:
-        """Combine multiple reference samples."""
+        return await _combine_voice_prompts(audio_paths, reference_texts)
-        combined_audio = []
-        for path in audio_paths:
-            audio, _sr = load_audio(path)
-            audio = normalize_audio(audio)
-            combined_audio.append(audio)
-
-        mixed = np.concatenate(combined_audio)
-        mixed = normalize_audio(mixed)
-        combined_text = " ".join(reference_texts)
-        return mixed, combined_text
 
     async def generate(
         self,

backend/backends/luxtts_backend.py

@@ -7,16 +7,13 @@ Wraps the LuxTTS (ZipVoice) model for zero-shot voice cloning.
 
 import asyncio
 import logging
-from pathlib import Path
+from typing import Optional, Tuple
-from typing import List, Optional, Tuple
 
 import numpy as np
 
 from . import TTSBackend
-from ..utils.audio import normalize_audio, load_audio
+from .base import is_model_cached, get_torch_device, combine_voice_prompts as _combine_voice_prompts, model_load_progress
 from ..utils.cache import get_cache_key, get_cached_voice_prompt, cache_voice_prompt
-from ..utils.progress import get_progress_manager
-from ..utils.tasks import get_task_manager
 
 logger = logging.getLogger(__name__)
 
@@ -33,14 +30,7 @@ class LuxTTSBackend:
         self._device = None
 
     def _get_device(self) -> str:
-        """Get the best available device."""
+        return get_torch_device(allow_mps=True)
-        import torch
-
-        if torch.cuda.is_available():
-            return "cuda"
-        if hasattr(torch.backends, "mps") and torch.backends.mps.is_available():
-            return "mps"
-        return "cpu"
 
     def is_loaded(self) -> bool:
         return self.model is not None
@@ -55,35 +45,10 @@ class LuxTTSBackend:
         return LUXTTS_HF_REPO
 
     def _is_model_cached(self, model_size: str = "default") -> bool:
-        """Check if LuxTTS model weights are cached locally."""
+        return is_model_cached(
-        try:
+            LUXTTS_HF_REPO,
-            from huggingface_hub import constants as hf_constants
+            weight_extensions=(".pt", ".safetensors", ".onnx", ".bin"),
-
+        )
-            repo_cache = (
-                Path(hf_constants.HF_HUB_CACHE)
-                / ("models--" + LUXTTS_HF_REPO.replace("/", "--"))
-            )
-
-            if not repo_cache.exists():
-                return False
-
-            blobs_dir = repo_cache / "blobs"
-            if blobs_dir.exists() and any(blobs_dir.glob("*.incomplete")):
-                return False
-
-            snapshots_dir = repo_cache / "snapshots"
-            if snapshots_dir.exists():
-                has_weights = any(snapshots_dir.rglob("*.pt")) or any(
-                    snapshots_dir.rglob("*.safetensors")
-                ) or any(snapshots_dir.rglob("*.onnx")) or any(
-                    snapshots_dir.rglob("*.bin")
-                )
-                return has_weights
-
-            return False
-        except Exception as e:
-            logger.warning(f"Error checking LuxTTS cache: {e}")
-            return False
 
     async def load_model(self, model_size: str = "default") -> None:
         """Load the LuxTTS model."""
@@ -93,67 +58,25 @@ class LuxTTSBackend:
         await asyncio.to_thread(self._load_model_sync)
 
     def _load_model_sync(self):
-        """Synchronous model loading."""
-        from ..utils.hf_progress import HFProgressTracker, create_hf_progress_callback
-
-        progress_manager = get_progress_manager()
-        task_manager = get_task_manager()
         model_name = "luxtts"
-
         is_cached = self._is_model_cached()
 
-        # Set up HF progress tracking (intercepts tqdm for file-level progress)
+        with model_load_progress(model_name, is_cached):
-        progress_callback = create_hf_progress_callback(model_name, progress_manager)
-        tracker = HFProgressTracker(progress_callback, filter_non_downloads=is_cached)
-        tracker_context = tracker.patch_download()
-        tracker_context.__enter__()
-
-        if not is_cached:
-            task_manager.start_download(model_name)
-            progress_manager.update_progress(
-                model_name=model_name,
-                current=0,
-                total=0,
-                filename="Connecting to HuggingFace...",
-                status="downloading",
-            )
-
-        try:
             from zipvoice.luxvoice import LuxTTS
 
             device = self.device
             logger.info(f"Loading LuxTTS on {device}...")
 
-            # LuxTTS constructor downloads model and loads everything
+            if device == "cpu":
-            try:
+                import os
-                if device == "cpu":
+                threads = os.cpu_count() or 4
-                    import os
+                self.model = LuxTTS(
-                    threads = os.cpu_count() or 4
+                    model_path=LUXTTS_HF_REPO, device="cpu", threads=min(threads, 8),
-                    self.model = LuxTTS(
+                )
-                        model_path=LUXTTS_HF_REPO,
+            else:
-                        device="cpu",
+                self.model = LuxTTS(model_path=LUXTTS_HF_REPO, device=device)
-                        threads=min(threads, 8),
-                    )
-                else:
-                    self.model = LuxTTS(
-                        model_path=LUXTTS_HF_REPO,
-                        device=device,
-                    )
-            finally:
-                tracker_context.__exit__(None, None, None)
 
-            if not is_cached:
+        logger.info("LuxTTS loaded successfully")
-                progress_manager.mark_complete(model_name)
-                task_manager.complete_download(model_name)
-
-            logger.info("LuxTTS loaded successfully")
-
-        except Exception as e:
-            logger.error(f"Failed to load LuxTTS: {e}")
-            if not is_cached:
-                progress_manager.mark_error(model_name, str(e))
-                task_manager.error_download(model_name, str(e))
-            raise
 
     def unload_model(self) -> None:
         """Unload model to free memory."""
@@ -204,28 +127,8 @@ class LuxTTSBackend:
 
         return encoded, False
 
-    async def combine_voice_prompts(
+    async def combine_voice_prompts(self, audio_paths, reference_texts):
-        self,
+        return await _combine_voice_prompts(audio_paths, reference_texts, sample_rate=24000)
-        audio_paths: List[str],
-        reference_texts: List[str],
-    ) -> Tuple[np.ndarray, str]:
-        """
-        Combine multiple reference samples.
-
-        LuxTTS doesn't have native multi-prompt support, so we concatenate
-        the audio and let encode_prompt handle the combined clip.
-        """
-        combined_audio = []
-        for path in audio_paths:
-            audio, _sr = load_audio(path, sample_rate=24000)
-            audio = normalize_audio(audio)
-            combined_audio.append(audio)
-
-        mixed = np.concatenate(combined_audio)
-        mixed = normalize_audio(mixed)
-        combined_text = " ".join(reference_texts)
-
-        return mixed, combined_text
 
     async def generate(
         self,

backend/backends/mlx_backend.py

@@ -4,49 +4,44 @@ MLX backend implementation for TTS and STT using mlx-audio.
 
 from typing import Optional, List, Tuple
 import asyncio
+import logging
 import numpy as np
 import os
 from pathlib import Path
 
+logger = logging.getLogger(__name__)
+
 # PATCH: Import and apply offline patch BEFORE any huggingface_hub usage
 # This prevents mlx_audio from making network requests when models are cached
 from ..utils.hf_offline_patch import patch_huggingface_hub_offline, ensure_original_qwen_config_cached
+
 patch_huggingface_hub_offline()
 ensure_original_qwen_config_cached()
 
-from . import TTSBackend, STTBackend
+from . import TTSBackend, STTBackend, LANGUAGE_CODE_TO_NAME, WHISPER_HF_REPOS
+from .base import is_model_cached, combine_voice_prompts as _combine_voice_prompts, model_load_progress
 from ..utils.cache import get_cache_key, get_cached_voice_prompt, cache_voice_prompt
-from ..utils.audio import normalize_audio, load_audio
-from ..utils.progress import get_progress_manager
-from ..utils.hf_progress import HFProgressTracker, create_hf_progress_callback
-from ..utils.tasks import get_task_manager
-
-LANGUAGE_CODE_TO_NAME = {
-    "zh": "chinese", "en": "english", "ja": "japanese", "ko": "korean",
-    "de": "german", "fr": "french", "ru": "russian", "pt": "portuguese",
-    "es": "spanish", "it": "italian",
-}
 
 
 class MLXTTSBackend:
     """MLX-based TTS backend using mlx-audio."""
-    
+
     def __init__(self, model_size: str = "1.7B"):
         self.model = None
         self.model_size = model_size
         self._current_model_size = None
-    
+
     def is_loaded(self) -> bool:
         """Check if model is loaded."""
         return self.model is not None
-    
+
     def _get_model_path(self, model_size: str) -> str:
         """
         Get the MLX model path.
-        
+
         Args:
             model_size: Model size (1.7B or 0.6B)
-            
+
         Returns:
             HuggingFace Hub model ID for MLX
         """
@@ -56,187 +51,90 @@ class MLXTTSBackend:
             # 0.6B not yet converted to MLX format
             "0.6B": "mlx-community/Qwen3-TTS-12Hz-1.7B-Base-bf16",  # Fallback to 1.7B
         }
-        
+
         if model_size not in mlx_model_map:
             raise ValueError(f"Unknown model size: {model_size}")
-        
+
         hf_model_id = mlx_model_map[model_size]
-        print(f"Will download MLX model from HuggingFace Hub: {hf_model_id}")
+        logger.info("Will download MLX model from HuggingFace Hub: %s", hf_model_id)
-        
+
         return hf_model_id
-    
+
     def _is_model_cached(self, model_size: str) -> bool:
-        """
+        return is_model_cached(
-        Check if the model is already cached locally AND fully downloaded.
+            self._get_model_path(model_size),
-        
+            weight_extensions=(".safetensors", ".bin", ".npz"),
-        Args:
+        )
-            model_size: Model size to check
+
-            
-        Returns:
-            True if model is fully cached, False if missing or incomplete
-        """
-        try:
-            from huggingface_hub import constants as hf_constants
-            model_path = self._get_model_path(model_size)
-            repo_cache = Path(hf_constants.HF_HUB_CACHE) / ("models--" + model_path.replace("/", "--"))
-            
-            if not repo_cache.exists():
-                return False
-            
-            # Check for .incomplete files - if any exist, download is still in progress
-            blobs_dir = repo_cache / "blobs"
-            if blobs_dir.exists() and any(blobs_dir.glob("*.incomplete")):
-                print(f"[_is_model_cached] Found .incomplete files for {model_size}, treating as not cached")
-                return False
-            
-            # Check that actual model weight files exist in snapshots
-            snapshots_dir = repo_cache / "snapshots"
-            if snapshots_dir.exists():
-                has_weights = (
-                    any(snapshots_dir.rglob("*.safetensors")) or
-                    any(snapshots_dir.rglob("*.bin")) or
-                    any(snapshots_dir.rglob("*.npz"))
-                )
-                if not has_weights:
-                    print(f"[_is_model_cached] No model weights found for {model_size}, treating as not cached")
-                    return False
-            
-            return True
-        except Exception as e:
-            print(f"[_is_model_cached] Error checking cache for {model_size}: {e}")
-            return False
-    
     async def load_model_async(self, model_size: Optional[str] = None):
         """
         Lazy load the MLX TTS model.
-        
+
         Args:
             model_size: Model size to load (1.7B or 0.6B)
         """
         if model_size is None:
             model_size = self.model_size
-            
+
         # If already loaded with correct size, return
         if self.model is not None and self._current_model_size == model_size:
             return
-        
+
         # Unload existing model if different size requested
         if self.model is not None and self._current_model_size != model_size:
             self.unload_model()
-        
+
         # Run blocking load in thread pool
         await asyncio.to_thread(self._load_model_sync, model_size)
-    
+
     # Alias for compatibility
     load_model = load_model_async
-    
+
     def _load_model_sync(self, model_size: str):
         """Synchronous model loading."""
+        model_path = self._get_model_path(model_size)
+        model_name = f"qwen-tts-{model_size}"
+        is_cached = self._is_model_cached(model_size)
+
+        # Force offline mode when cached to avoid network requests
+        original_hf_hub_offline = os.environ.get("HF_HUB_OFFLINE")
+        if is_cached:
+            os.environ["HF_HUB_OFFLINE"] = "1"
+            logger.info("[PATCH] Model %s is cached, forcing HF_HUB_OFFLINE=1 to avoid network requests", model_size)
+
         try:
-            # Get model path BEFORE importing mlx_audio
+            with model_load_progress(model_name, is_cached):
-            model_path = self._get_model_path(model_size)
+                from mlx_audio.tts import load
-            
+
-            # Set up progress tracking
+                logger.info("Loading MLX TTS model %s...", model_size)
-            progress_manager = get_progress_manager()
+
-            task_manager = get_task_manager()
+                try:
-            model_name = f"qwen-tts-{model_size}"
-            
-            # Check if model is already cached
-            is_cached = self._is_model_cached(model_size)
-            
-            # Set up progress callback
-            # If cached: filter out non-download progress
-            # If not cached: report all progress (we're actually downloading)
-            progress_callback = create_hf_progress_callback(model_name, progress_manager)
-            tracker = HFProgressTracker(progress_callback, filter_non_downloads=is_cached)
-            
-            print(f"Loading MLX TTS model {model_size}...")
-            
-            # Only track download progress if model is NOT cached
-            if not is_cached:
-                # Start tracking download task
-                task_manager.start_download(model_name)
-                
-                # Initialize progress state so SSE endpoint has initial data to send
-                # This provides immediate feedback while HuggingFace fetches metadata
-                progress_manager.update_progress(
-                    model_name=model_name,
-                    current=0,
-                    total=0,  # Will be updated once actual total is known
-                    filename="Connecting to HuggingFace...",
-                    status="downloading",
-                )
-            
-            # IMPORTANT: Patch tqdm BEFORE importing mlx_audio
-            # Otherwise mlx_audio caches reference to original tqdm
-            tracker_context = tracker.patch_download()
-            tracker_context.__enter__()
-            
-            # PATCH: Force offline mode when model is already cached
-            # This prevents crashes when HuggingFace is unreachable
-            original_hf_hub_offline = os.environ.get("HF_HUB_OFFLINE")
-            if is_cached:
-                os.environ["HF_HUB_OFFLINE"] = "1"
-                print(f"[PATCH] Model {model_size} is cached, forcing HF_HUB_OFFLINE=1 to avoid network requests")
-            
-            # Import mlx_audio AFTER patching tqdm
-            from mlx_audio.tts import load
-            
-            # Load MLX model (downloads automatically)
-            try:
-                self.model = load(model_path)
-            except Exception as load_error:
-                # If offline mode failed, try with network enabled as fallback
-                if is_cached and "offline" in str(load_error).lower():
-                    print(f"[PATCH] Offline load failed, trying with network: {load_error}")
-                    os.environ.pop("HF_HUB_OFFLINE", None)
                     self.model = load(model_path)
-                else:
+                except Exception as load_error:
-                    raise
+                    if is_cached and "offline" in str(load_error).lower():
-            finally:
+                        logger.warning("[PATCH] Offline load failed, trying with network: %s", load_error)
-                # Exit the patch context
+                        os.environ.pop("HF_HUB_OFFLINE", None)
-                tracker_context.__exit__(None, None, None)
+                        self.model = load(model_path)
-                # Restore original HF_HUB_OFFLINE setting
+                    else:
-                if original_hf_hub_offline is not None:
+                        raise
-                    os.environ["HF_HUB_OFFLINE"] = original_hf_hub_offline
+        finally:
-                else:
+            if original_hf_hub_offline is not None:
-                    os.environ.pop("HF_HUB_OFFLINE", None)
+                os.environ["HF_HUB_OFFLINE"] = original_hf_hub_offline
-            
+            else:
-            # Only mark download as complete if we were tracking it
+                os.environ.pop("HF_HUB_OFFLINE", None)
-            if not is_cached:
+
-                progress_manager.mark_complete(model_name)
+        self._current_model_size = model_size
-                task_manager.complete_download(model_name)
+        self.model_size = model_size
-            
+        logger.info("MLX TTS model %s loaded successfully", model_size)
-            self._current_model_size = model_size
+
-            self.model_size = model_size
-            
-            print(f"MLX TTS model {model_size} loaded successfully")
-            
-        except ImportError as e:
-            print(f"Error: mlx_audio package not found. Install with: pip install mlx-audio")
-            progress_manager = get_progress_manager()
-            task_manager = get_task_manager()
-            model_name = f"qwen-tts-{model_size}"
-            progress_manager.mark_error(model_name, str(e))
-            task_manager.error_download(model_name, str(e))
-            raise
-        except Exception as e:
-            print(f"Error loading MLX TTS model: {e}")
-            progress_manager = get_progress_manager()
-            task_manager = get_task_manager()
-            model_name = f"qwen-tts-{model_size}"
-            progress_manager.mark_error(model_name, str(e))
-            task_manager.error_download(model_name, str(e))
-            raise
-    
     def unload_model(self):
         """Unload the model to free memory."""
         if self.model is not None:
             del self.model
             self.model = None
             self._current_model_size = None
-            print("MLX TTS model unloaded")
+            logger.info("MLX TTS model unloaded")
-    
+
     async def create_voice_prompt(
         self,
         audio_path: str,
@@ -245,20 +143,20 @@ class MLXTTSBackend:
     ) -> Tuple[dict, bool]:
         """
         Create voice prompt from reference audio.
-        
+
         MLX backend stores voice prompt as a dict with audio path and text.
         The actual voice prompt processing happens during generation.
-        
+
         Args:
             audio_path: Path to reference audio file
             reference_text: Transcript of reference audio
             use_cache: Whether to use cached prompt if available
-            
+
         Returns:
             Tuple of (voice_prompt_dict, was_cached)
         """
         await self.load_model_async(None)
-        
+
         # Check cache if enabled
         if use_cache:
             cache_key = get_cache_key(audio_path, reference_text)
@@ -272,53 +170,25 @@ class MLXTTSBackend:
                         return cached_prompt, True
                     else:
                         # Cached file no longer exists, invalidate cache
-                        print(f"Cached audio file not found: {cached_audio_path}, regenerating prompt")
+                        logger.warning("Cached audio file not found: %s, regenerating prompt", cached_audio_path)
-        
+
         # MLX voice prompt format - store audio path and text
         # The model will process this during generation
         voice_prompt_items = {
             "ref_audio": str(audio_path),
             "ref_text": reference_text,
         }
-        
+
         # Cache if enabled
         if use_cache:
             cache_key = get_cache_key(audio_path, reference_text)
             cache_voice_prompt(cache_key, voice_prompt_items)
-        
+
         return voice_prompt_items, False
-    
+
-    async def combine_voice_prompts(
+    async def combine_voice_prompts(self, audio_paths, reference_texts):
-        self,
+        return await _combine_voice_prompts(audio_paths, reference_texts)
-        audio_paths: List[str],
+
-        reference_texts: List[str],
-    ) -> Tuple[np.ndarray, str]:
-        """
-        Combine multiple reference samples for better quality.
-        
-        Args:
-            audio_paths: List of audio file paths
-            reference_texts: List of reference texts
-            
-        Returns:
-            Tuple of (combined_audio, combined_text)
-        """
-        combined_audio = []
-        
-        for audio_path in audio_paths:
-            audio, sr = load_audio(audio_path)
-            audio = normalize_audio(audio)
-            combined_audio.append(audio)
-        
-        # Concatenate audio
-        mixed = np.concatenate(combined_audio)
-        mixed = normalize_audio(mixed)
-        
-        # Combine texts
-        combined_text = " ".join(reference_texts)
-        
-        return mixed, combined_text
-    
     async def generate(
         self,
         text: str,
@@ -342,7 +212,7 @@ class MLXTTSBackend:
         """
         await self.load_model_async(None)
 
-        print(f"Generating audio for text: {text}")
+        logger.info("Generating audio for text: %s", text)
 
         def _generate_sync():
             """Run synchronous generation in thread pool."""
@@ -354,20 +224,21 @@ class MLXTTSBackend:
             # Set seed if provided (MLX uses numpy random)
             if seed is not None:
                 import mlx.core as mx
+
                 np.random.seed(seed)
                 mx.random.seed(seed)
-            
+
             # Extract voice prompt info
             ref_audio = voice_prompt.get("ref_audio") or voice_prompt.get("ref_audio_path")
             ref_text = voice_prompt.get("ref_text", "")
-            
+
             # Validate that the audio file exists
             if ref_audio and not Path(ref_audio).exists():
-                print(f"Warning: Audio file not found: {ref_audio}")
+                logger.warning("Audio file not found: %s", ref_audio)
-                print("This may be due to a cached voice prompt referencing a deleted temp file.")
+                logger.warning("This may be due to a cached voice prompt referencing a deleted temp file.")
-                print("Regenerating without voice prompt.")
+                logger.warning("Regenerating without voice prompt.")
                 ref_audio = None
-            
+
             # Check if model supports voice cloning via generate method
             # MLX API may support ref_audio parameter directly
             try:
@@ -375,6 +246,7 @@ class MLXTTSBackend:
                 if ref_audio:
                     # Check if generate accepts ref_audio parameter
                     import inspect
+
                     sig = inspect.signature(self.model.generate)
                     if "ref_audio" in sig.parameters:
                         # Generate with voice cloning
@@ -393,18 +265,18 @@ class MLXTTSBackend:
                         sample_rate = result.sample_rate
             except Exception as e:
                 # If voice cloning fails, try without it
-                print(f"Warning: Voice cloning failed, generating without voice prompt: {e}")
+                logger.warning("Voice cloning failed, generating without voice prompt: %s", e)
                 for result in self.model.generate(text, lang_code=lang):
                     audio_chunks.append(np.array(result.audio))
                     sample_rate = result.sample_rate
-            
+
             # Concatenate all chunks
             if audio_chunks:
                 audio = np.concatenate([np.asarray(chunk, dtype=np.float32) for chunk in audio_chunks])
             else:
                 # Fallback: empty audio
                 audio = np.array([], dtype=np.float32)
-            
+
             return audio, sample_rate
 
         # Run blocking inference in thread pool
@@ -413,183 +285,80 @@ class MLXTTSBackend:
         return audio, sample_rate
 
 
-WHISPER_HF_REPOS = {
-    "base": "openai/whisper-base",
-    "small": "openai/whisper-small",
-    "medium": "openai/whisper-medium",
-    "large": "openai/whisper-large-v3",
-}
-
-
 class MLXSTTBackend:
     """MLX-based STT backend using mlx-audio Whisper."""
 
     def __init__(self, model_size: str = "base"):
         self.model = None
         self.model_size = model_size
-    
+
     def is_loaded(self) -> bool:
         """Check if model is loaded."""
         return self.model is not None
-    
+
     def _is_model_cached(self, model_size: str) -> bool:
-        """
+        hf_repo = WHISPER_HF_REPOS.get(model_size, f"openai/whisper-{model_size}")
-        Check if the Whisper model is already cached locally AND fully downloaded.
+        return is_model_cached(hf_repo, weight_extensions=(".safetensors", ".bin", ".npz"))
-        
+
-        Args:
-            model_size: Model size to check
-            
-        Returns:
-            True if model is fully cached, False if missing or incomplete
-        """
-        try:
-            from huggingface_hub import constants as hf_constants
-            hf_repo = WHISPER_HF_REPOS.get(model_size, f"openai/whisper-{model_size}")
-            repo_cache = Path(hf_constants.HF_HUB_CACHE) / ("models--" + hf_repo.replace("/", "--"))
-            
-            if not repo_cache.exists():
-                return False
-            
-            # Check for .incomplete files - if any exist, download is still in progress
-            blobs_dir = repo_cache / "blobs"
-            if blobs_dir.exists() and any(blobs_dir.glob("*.incomplete")):
-                print(f"[_is_model_cached] Found .incomplete files for whisper-{model_size}, treating as not cached")
-                return False
-            
-            # Check that actual model weight files exist in snapshots
-            snapshots_dir = repo_cache / "snapshots"
-            if snapshots_dir.exists():
-                has_weights = (
-                    any(snapshots_dir.rglob("*.safetensors")) or
-                    any(snapshots_dir.rglob("*.bin")) or
-                    any(snapshots_dir.rglob("*.npz"))
-                )
-                if not has_weights:
-                    print(f"[_is_model_cached] No model weights found for whisper-{model_size}, treating as not cached")
-                    return False
-            
-            return True
-        except Exception as e:
-            print(f"[_is_model_cached] Error checking cache for whisper-{model_size}: {e}")
-            return False
-    
     async def load_model_async(self, model_size: Optional[str] = None):
         """
         Lazy load the MLX Whisper model.
-        
+
         Args:
             model_size: Model size (tiny, base, small, medium, large)
         """
         if model_size is None:
             model_size = self.model_size
-        
+
         if self.model is not None and self.model_size == model_size:
             return
-        
+
         # Run blocking load in thread pool
         await asyncio.to_thread(self._load_model_sync, model_size)
-    
+
     # Alias for compatibility
     load_model = load_model_async
-    
+
     def _load_model_sync(self, model_size: str):
         """Synchronous model loading."""
-        try:
+        progress_model_name = f"whisper-{model_size}"
-            progress_manager = get_progress_manager()
+        is_cached = self._is_model_cached(model_size)
-            task_manager = get_task_manager()
-            progress_model_name = f"whisper-{model_size}"
 
-            # Check if model is already cached
+        with model_load_progress(progress_model_name, is_cached):
-            is_cached = self._is_model_cached(model_size)
-
-            # Set up progress callback and tracker
-            # If cached: filter out non-download progress
-            # If not cached: report all progress (we're actually downloading)
-            progress_callback = create_hf_progress_callback(progress_model_name, progress_manager)
-            tracker = HFProgressTracker(progress_callback, filter_non_downloads=is_cached)
-
-            # Patch tqdm BEFORE importing mlx_audio
-            tracker_context = tracker.patch_download()
-            tracker_context.__enter__()
-
-            # Import mlx_audio
             from mlx_audio.stt import load
 
-            # MLX Whisper uses the standard OpenAI models
             model_name = WHISPER_HF_REPOS.get(model_size, f"openai/whisper-{model_size}")
+            logger.info("Loading MLX Whisper model %s...", model_size)
+            self.model = load(model_name)
 
-            print(f"Loading MLX Whisper model {model_size}...")
+        self.model_size = model_size
+        logger.info("MLX Whisper model %s loaded successfully", model_size)
 
-            # Only track download progress if model is NOT cached
-            if not is_cached:
-                # Start tracking download task
-                task_manager.start_download(progress_model_name)
-                
-                # Initialize progress state so SSE endpoint has initial data to send
-                progress_manager.update_progress(
-                    model_name=progress_model_name,
-                    current=0,
-                    total=0,
-                    filename="Connecting to HuggingFace...",
-                    status="downloading",
-                )
-
-            # Load the model (tqdm is patched, but filters out non-download progress)
-            try:
-                self.model = load(model_name)
-            finally:
-                # Exit the patch context
-                tracker_context.__exit__(None, None, None)
-            
-            # Only mark download as complete if we were tracking it
-            if not is_cached:
-                progress_manager.mark_complete(progress_model_name)
-                task_manager.complete_download(progress_model_name)
-            
-            self.model_size = model_size
-            
-            print(f"MLX Whisper model {model_size} loaded successfully")
-            
-        except ImportError as e:
-            print(f"Error: mlx_audio package not found. Install with: pip install mlx-audio")
-            progress_manager = get_progress_manager()
-            task_manager = get_task_manager()
-            progress_model_name = f"whisper-{model_size}"
-            progress_manager.mark_error(progress_model_name, str(e))
-            task_manager.error_download(progress_model_name, str(e))
-            raise
-        except Exception as e:
-            print(f"Error loading MLX Whisper model: {e}")
-            progress_manager = get_progress_manager()
-            task_manager = get_task_manager()
-            progress_model_name = f"whisper-{model_size}"
-            progress_manager.mark_error(progress_model_name, str(e))
-            task_manager.error_download(progress_model_name, str(e))
-            raise
-    
     def unload_model(self):
         """Unload the model to free memory."""
         if self.model is not None:
             del self.model
             self.model = None
-            print("MLX Whisper model unloaded")
+            logger.info("MLX Whisper model unloaded")
-    
+
     async def transcribe(
         self,
         audio_path: str,
         language: Optional[str] = None,
+        model_size: Optional[str] = None,
     ) -> str:
         """
         Transcribe audio to text.
 
         Args:
             audio_path: Path to audio file
-            language: Optional language hint (en or zh)
+            language: Optional language hint
+            model_size: Optional model size override
 
         Returns:
             Transcribed text
         """
-        await self.load_model_async(None)
+        await self.load_model_async(model_size)
 
         def _transcribe_sync():
             """Run synchronous transcription in thread pool."""

backend/backends/pytorch_backend.py

@@ -4,67 +4,47 @@ PyTorch backend implementation for TTS and STT.
 
 from typing import Optional, List, Tuple
 import asyncio
+import logging
 import torch
 import numpy as np
-from pathlib import Path
 
-from . import TTSBackend, STTBackend
+logger = logging.getLogger(__name__)
+
+from . import TTSBackend, STTBackend, LANGUAGE_CODE_TO_NAME, WHISPER_HF_REPOS
+from .base import (
+    is_model_cached,
+    get_torch_device,
+    combine_voice_prompts as _combine_voice_prompts,
+    model_load_progress,
+)
 from ..utils.cache import get_cache_key, get_cached_voice_prompt, cache_voice_prompt
-from ..utils.audio import normalize_audio, load_audio
+from ..utils.audio import load_audio
-from ..utils.progress import get_progress_manager
-from ..utils.hf_progress import HFProgressTracker, create_hf_progress_callback
-from ..utils.tasks import get_task_manager
-
-LANGUAGE_CODE_TO_NAME = {
-    "zh": "chinese", "en": "english", "ja": "japanese", "ko": "korean",
-    "de": "german", "fr": "french", "ru": "russian", "pt": "portuguese",
-    "es": "spanish", "it": "italian",
-}
 
 
 class PyTorchTTSBackend:
     """PyTorch-based TTS backend using Qwen3-TTS."""
-    
+
     def __init__(self, model_size: str = "1.7B"):
         self.model = None
         self.model_size = model_size
         self.device = self._get_device()
         self._current_model_size = None
-    
+
     def _get_device(self) -> str:
         """Get the best available device."""
-        if torch.cuda.is_available():
+        return get_torch_device(allow_xpu=True, allow_directml=True)
-            return "cuda"
+
-        # Intel Arc / Intel Xe GPU via intel-extension-for-pytorch (IPEX)
-        try:
-            import intel_extension_for_pytorch  # noqa: F401
-            if hasattr(torch, 'xpu') and torch.xpu.is_available():
-                return "xpu"
-        except ImportError:
-            pass
-        # Any GPU on Windows via DirectML (torch-directml)
-        try:
-            import torch_directml
-            if torch_directml.device_count() > 0:
-                return torch_directml.device(0)
-        except ImportError:
-            pass
-        # MPS (Apple Silicon) — kept for completeness but MLX backend is preferred
-        if hasattr(torch.backends, 'mps') and torch.backends.mps.is_available():
-            return "cpu"  # MPS disabled for stability; MLX backend handles Apple Silicon
-        return "cpu"
-    
     def is_loaded(self) -> bool:
         """Check if model is loaded."""
         return self.model is not None
-    
+
     def _get_model_path(self, model_size: str) -> str:
         """
         Get the HuggingFace Hub model ID.
-        
+
         Args:
             model_size: Model size (1.7B or 0.6B)
-            
+
         Returns:
             HuggingFace Hub model ID
         """
@@ -72,179 +52,79 @@ class PyTorchTTSBackend:
             "1.7B": "Qwen/Qwen3-TTS-12Hz-1.7B-Base",
             "0.6B": "Qwen/Qwen3-TTS-12Hz-0.6B-Base",
         }
-        
+
         if model_size not in hf_model_map:
             raise ValueError(f"Unknown model size: {model_size}")
-        
+
         return hf_model_map[model_size]
-    
+
     def _is_model_cached(self, model_size: str) -> bool:
-        """
+        return is_model_cached(self._get_model_path(model_size))
-        Check if the model is already cached locally AND fully downloaded.
+
-        
-        Args:
-            model_size: Model size to check
-            
-        Returns:
-            True if model is fully cached, False if missing or incomplete
-        """
-        try:
-            from huggingface_hub import constants as hf_constants
-            model_path = self._get_model_path(model_size)
-            repo_cache = Path(hf_constants.HF_HUB_CACHE) / ("models--" + model_path.replace("/", "--"))
-            
-            if not repo_cache.exists():
-                return False
-            
-            # Check for .incomplete files - if any exist, download is still in progress
-            blobs_dir = repo_cache / "blobs"
-            if blobs_dir.exists() and any(blobs_dir.glob("*.incomplete")):
-                print(f"[_is_model_cached] Found .incomplete files for {model_size}, treating as not cached")
-                return False
-            
-            # Check that actual model weight files exist in snapshots
-            snapshots_dir = repo_cache / "snapshots"
-            if snapshots_dir.exists():
-                has_weights = (
-                    any(snapshots_dir.rglob("*.safetensors")) or
-                    any(snapshots_dir.rglob("*.bin"))
-                )
-                if not has_weights:
-                    print(f"[_is_model_cached] No model weights found for {model_size}, treating as not cached")
-                    return False
-            
-            return True
-        except Exception as e:
-            print(f"[_is_model_cached] Error checking cache for {model_size}: {e}")
-            return False
-    
     async def load_model_async(self, model_size: Optional[str] = None):
         """
         Lazy load the TTS model with automatic downloading from HuggingFace Hub.
-        
+
         Args:
             model_size: Model size to load (1.7B or 0.6B)
         """
         if model_size is None:
             model_size = self.model_size
-            
+
         # If already loaded with correct size, return
         if self.model is not None and self._current_model_size == model_size:
             return
-        
+
         # Unload existing model if different size requested
         if self.model is not None and self._current_model_size != model_size:
             self.unload_model()
-        
+
         # Run blocking load in thread pool
         await asyncio.to_thread(self._load_model_sync, model_size)
-    
+
     # Alias for compatibility
     load_model = load_model_async
-    
+
     def _load_model_sync(self, model_size: str):
         """Synchronous model loading."""
-        try:
+        model_name = f"qwen-tts-{model_size}"
-            progress_manager = get_progress_manager()
+        is_cached = self._is_model_cached(model_size)
-            task_manager = get_task_manager()
-            model_name = f"qwen-tts-{model_size}"
 
-            # Check if model is already cached
+        with model_load_progress(model_name, is_cached):
-            is_cached = self._is_model_cached(model_size)
-
-            # Set up progress callback and tracker
-            # If cached: filter out non-download progress (like "Segment 1/1" during generation)
-            # If not cached: report all progress (we're actually downloading)
-            progress_callback = create_hf_progress_callback(model_name, progress_manager)
-            tracker = HFProgressTracker(progress_callback, filter_non_downloads=is_cached)
-
-            # Patch tqdm BEFORE importing qwen_tts
-            tracker_context = tracker.patch_download()
-            tracker_context.__enter__()
-
-            # Import qwen_tts
             from qwen_tts import Qwen3TTSModel
 
-            # Get model path (local or HuggingFace Hub ID)
             model_path = self._get_model_path(model_size)
+            logger.info("Loading TTS model %s on %s...", model_size, self.device)
 
-            print(f"Loading TTS model {model_size} on {self.device}...")
+            if self.device == "cpu":
-
+                self.model = Qwen3TTSModel.from_pretrained(
-            # Only track download progress if model is NOT cached
+                    model_path,
-            if not is_cached:
+                    torch_dtype=torch.float32,
-                # Start tracking download task
+                    low_cpu_mem_usage=False,
-                task_manager.start_download(model_name)
+                )
-
+            else:
-                # Initialize progress state so SSE endpoint has initial data to send
+                self.model = Qwen3TTSModel.from_pretrained(
-                progress_manager.update_progress(
+                    model_path,
-                    model_name=model_name,
+                    device_map=self.device,
-                    current=0,
+                    torch_dtype=torch.bfloat16,
-                    total=0,  # Will be updated once actual total is known
-                    filename="Connecting to HuggingFace...",
-                    status="downloading",
                 )
 
-            # Load the model (tqdm is patched, but filters out non-download progress)
+        self._current_model_size = model_size
-            try:
+        self.model_size = model_size
-                # Don't pass device_map on CPU: accelerate's meta-tensor mechanism
+        logger.info("TTS model %s loaded successfully", model_size)
-                # causes "Cannot copy out of meta tensor" when moving to CPU.
+
-                # Instead load directly then call .to(device) if needed.
-                if self.device == "cpu":
-                    self.model = Qwen3TTSModel.from_pretrained(
-                        model_path,
-                        torch_dtype=torch.float32,
-                        low_cpu_mem_usage=False,
-                    )
-                else:
-                    self.model = Qwen3TTSModel.from_pretrained(
-                        model_path,
-                        device_map=self.device,
-                        torch_dtype=torch.bfloat16,
-                    )
-            finally:
-                # Exit the patch context
-                tracker_context.__exit__(None, None, None)
-            
-            # Only mark download as complete if we were tracking it
-            if not is_cached:
-                progress_manager.mark_complete(model_name)
-                task_manager.complete_download(model_name)
-            
-            self._current_model_size = model_size
-            self.model_size = model_size
-            
-            print(f"TTS model {model_size} loaded successfully")
-            
-        except ImportError as e:
-            print(f"Error: qwen_tts package not found. Install with: pip install git+https://github.com/QwenLM/Qwen3-TTS.git")
-            progress_manager = get_progress_manager()
-            task_manager = get_task_manager()
-            model_name = f"qwen-tts-{model_size}"
-            progress_manager.mark_error(model_name, str(e))
-            task_manager.error_download(model_name, str(e))
-            raise
-        except Exception as e:
-            print(f"Error loading TTS model: {e}")
-            print(f"Tip: The model will be automatically downloaded from HuggingFace Hub on first use.")
-            progress_manager = get_progress_manager()
-            task_manager = get_task_manager()
-            model_name = f"qwen-tts-{model_size}"
-            progress_manager.mark_error(model_name, str(e))
-            task_manager.error_download(model_name, str(e))
-            raise
-    
     def unload_model(self):
         """Unload the model to free memory."""
         if self.model is not None:
             del self.model
             self.model = None
             self._current_model_size = None
-            
+
             if torch.cuda.is_available():
                 torch.cuda.empty_cache()
-            
+
-            print("TTS model unloaded")
+            logger.info("TTS model unloaded")
-    
+
     async def create_voice_prompt(
         self,
         audio_path: str,
@@ -253,17 +133,17 @@ class PyTorchTTSBackend:
     ) -> Tuple[dict, bool]:
         """
         Create voice prompt from reference audio.
-        
+
         Args:
             audio_path: Path to reference audio file
             reference_text: Transcript of reference audio
             use_cache: Whether to use cached prompt if available
-            
+
         Returns:
             Tuple of (voice_prompt_dict, was_cached)
         """
         await self.load_model_async(None)
-        
+
         # Check cache if enabled
         if use_cache:
             cache_key = get_cache_key(audio_path, reference_text)
@@ -279,7 +159,7 @@ class PyTorchTTSBackend:
                     # Legacy cache format - convert to dict
                     # This shouldn't happen in practice, but handle it
                     return {"prompt": cached_prompt}, True
-        
+
         def _create_prompt_sync():
             """Run synchronous voice prompt creation in thread pool."""
             return self.model.create_voice_clone_prompt(
@@ -287,48 +167,24 @@ class PyTorchTTSBackend:
                 ref_text=reference_text,
                 x_vector_only_mode=False,
             )
-        
+
         # Run blocking operation in thread pool
         voice_prompt_items = await asyncio.to_thread(_create_prompt_sync)
-        
+
         # Cache if enabled
         if use_cache:
             cache_key = get_cache_key(audio_path, reference_text)
             cache_voice_prompt(cache_key, voice_prompt_items)
-        
+
         return voice_prompt_items, False
-    
+
     async def combine_voice_prompts(
         self,
         audio_paths: List[str],
         reference_texts: List[str],
     ) -> Tuple[np.ndarray, str]:
-        """
+        return await _combine_voice_prompts(audio_paths, reference_texts)
-        Combine multiple reference samples for better quality.
+
-        
-        Args:
-            audio_paths: List of audio file paths
-            reference_texts: List of reference texts
-            
-        Returns:
-            Tuple of (combined_audio, combined_text)
-        """
-        combined_audio = []
-        
-        for audio_path in audio_paths:
-            audio, sr = load_audio(audio_path)
-            audio = normalize_audio(audio)
-            combined_audio.append(audio)
-        
-        # Concatenate audio
-        mixed = np.concatenate(combined_audio)
-        mixed = normalize_audio(mixed)
-        
-        # Combine texts
-        combined_text = " ".join(reference_texts)
-        
-        return mixed, combined_text
-    
     async def generate(
         self,
         text: str,
@@ -376,15 +232,6 @@ class PyTorchTTSBackend:
         return audio, sample_rate
 
 
-WHISPER_HF_REPOS = {
-    "base": "openai/whisper-base",
-    "small": "openai/whisper-small",
-    "medium": "openai/whisper-medium",
-    "large": "openai/whisper-large-v3",
-    "turbo": "openai/whisper-large-v3-turbo",
-}
-
-
 class PyTorchSTTBackend:
     """PyTorch-based STT backend using Whisper."""
 
@@ -393,72 +240,18 @@ class PyTorchSTTBackend:
         self.processor = None
         self.model_size = model_size
         self.device = self._get_device()
-    
+
     def _get_device(self) -> str:
         """Get the best available device."""
-        if torch.cuda.is_available():
+        return get_torch_device(allow_xpu=True, allow_directml=True)
-            return "cuda"
+
-        # Intel Arc / Intel Xe GPU via intel-extension-for-pytorch (IPEX)
-        try:
-            import intel_extension_for_pytorch  # noqa: F401
-            if hasattr(torch, 'xpu') and torch.xpu.is_available():
-                return "xpu"
-        except ImportError:
-            pass
-        # Any GPU on Windows via DirectML (torch-directml)
-        try:
-            import torch_directml
-            if torch_directml.device_count() > 0:
-                return torch_directml.device(0)
-        except ImportError:
-            pass
-        if hasattr(torch.backends, 'mps') and torch.backends.mps.is_available():
-            return "cpu"  # MPS disabled for stability
-        return "cpu"
-    
     def is_loaded(self) -> bool:
         """Check if model is loaded."""
         return self.model is not None
-    
+
     def _is_model_cached(self, model_size: str) -> bool:
-        """
+        hf_repo = WHISPER_HF_REPOS.get(model_size, f"openai/whisper-{model_size}")
-        Check if the Whisper model is already cached locally AND fully downloaded.
+        return is_model_cached(hf_repo)
-        
-        Args:
-            model_size: Model size to check
-            
-        Returns:
-            True if model is fully cached, False if missing or incomplete
-        """
-        try:
-            from huggingface_hub import constants as hf_constants
-            hf_repo = WHISPER_HF_REPOS.get(model_size, f"openai/whisper-{model_size}")
-            repo_cache = Path(hf_constants.HF_HUB_CACHE) / ("models--" + hf_repo.replace("/", "--"))
-
-            if not repo_cache.exists():
-                return False
-
-            # Check for .incomplete files - if any exist, download is still in progress
-            blobs_dir = repo_cache / "blobs"
-            if blobs_dir.exists() and any(blobs_dir.glob("*.incomplete")):
-                print(f"[_is_model_cached] Found .incomplete files for whisper-{model_size}, treating as not cached")
-                return False
-
-            # Check that actual model weight files exist in snapshots
-            snapshots_dir = repo_cache / "snapshots"
-            if snapshots_dir.exists():
-                has_weights = (
-                    any(snapshots_dir.rglob("*.safetensors")) or
-                    any(snapshots_dir.rglob("*.bin"))
-                )
-                if not has_weights:
-                    print(f"[_is_model_cached] No model weights found for whisper-{model_size}, treating as not cached")
-                    return False
-
-            return True
-        except Exception as e:
-            print(f"[_is_model_cached] Error checking cache for whisper-{model_size}: {e}")
-            return False
 
     async def load_model_async(self, model_size: Optional[str] = None):
         """
@@ -467,95 +260,35 @@ class PyTorchSTTBackend:
         Args:
             model_size: Model size (tiny, base, small, medium, large)
         """
-        print(f"[DEBUG] load_model_async called with size: {model_size}")
         if model_size is None:
             model_size = self.model_size
 
-        print(f"[DEBUG] Model already loaded? {self.model is not None}, current size: {self.model_size}, requested: {model_size}")
         if self.model is not None and self.model_size == model_size:
-            print(f"[DEBUG] Early return - model already loaded")
             return
 
-        print(f"[DEBUG] Calling asyncio.to_thread for _load_model_sync")
-        # Run blocking load in thread pool
         await asyncio.to_thread(self._load_model_sync, model_size)
-        print(f"[DEBUG] asyncio.to_thread completed")
+
-    
     # Alias for compatibility
     load_model = load_model_async
-    
+
     def _load_model_sync(self, model_size: str):
         """Synchronous model loading."""
-        print(f"[DEBUG] _load_model_sync called for Whisper {model_size}")
+        progress_model_name = f"whisper-{model_size}"
-        try:
+        is_cached = self._is_model_cached(model_size)
-            progress_manager = get_progress_manager()
-            task_manager = get_task_manager()
-            progress_model_name = f"whisper-{model_size}"
 
-            # Check if model is already cached
+        with model_load_progress(progress_model_name, is_cached):
-            is_cached = self._is_model_cached(model_size)
-
-            # Set up progress callback and tracker
-            # If cached: filter out non-download progress
-            # If not cached: report all progress (we're actually downloading)
-            progress_callback = create_hf_progress_callback(progress_model_name, progress_manager)
-            tracker = HFProgressTracker(progress_callback, filter_non_downloads=is_cached)
-
-            # Patch tqdm BEFORE importing transformers
-            print("[DEBUG] Starting tqdm patch BEFORE transformers import")
-            tracker_context = tracker.patch_download()
-            tracker_context.__enter__()
-            print("[DEBUG] tqdm patched, now importing transformers")
-
-            # Import transformers
             from transformers import WhisperProcessor, WhisperForConditionalGeneration
 
             model_name = WHISPER_HF_REPOS.get(model_size, f"openai/whisper-{model_size}")
-            print(f"[DEBUG] Model name: {model_name}")
+            logger.info("Loading Whisper model %s on %s...", model_size, self.device)
 
-            print(f"Loading Whisper model {model_size} on {self.device}...")
+            self.processor = WhisperProcessor.from_pretrained(model_name)
+            self.model = WhisperForConditionalGeneration.from_pretrained(model_name)
 
-            # Only track download progress if model is NOT cached
+        self.model.to(self.device)
-            if not is_cached:
+        self.model_size = model_size
-                # Start tracking download task
+        logger.info("Whisper model %s loaded successfully", model_size)
-                task_manager.start_download(progress_model_name)
 
-                # Initialize progress state so SSE endpoint has initial data to send
-                progress_manager.update_progress(
-                    model_name=progress_model_name,
-                    current=0,
-                    total=0,  # Will be updated once actual total is known
-                    filename="Connecting to HuggingFace...",
-                    status="downloading",
-                )
-
-            # Load models (tqdm is patched, but filters out non-download progress)
-            try:
-                self.processor = WhisperProcessor.from_pretrained(model_name)
-                self.model = WhisperForConditionalGeneration.from_pretrained(model_name)
-            finally:
-                # Exit the patch context
-                tracker_context.__exit__(None, None, None)
-            
-            # Only mark download as complete if we were tracking it
-            if not is_cached:
-                progress_manager.mark_complete(progress_model_name)
-                task_manager.complete_download(progress_model_name)
-            
-            self.model.to(self.device)
-            self.model_size = model_size
-            
-            print(f"Whisper model {model_size} loaded successfully")
-            
-        except Exception as e:
-            print(f"Error loading Whisper model: {e}")
-            progress_manager = get_progress_manager()
-            task_manager = get_task_manager()
-            progress_model_name = f"whisper-{model_size}"
-            progress_manager.mark_error(progress_model_name, str(e))
-            task_manager.error_download(progress_model_name, str(e))
-            raise
-    
     def unload_model(self):
         """Unload the model to free memory."""
         if self.model is not None:
@@ -563,34 +296,36 @@ class PyTorchSTTBackend:
             del self.processor
             self.model = None
             self.processor = None
-            
+
             if torch.cuda.is_available():
                 torch.cuda.empty_cache()
-            
+
-            print("Whisper model unloaded")
+            logger.info("Whisper model unloaded")
-    
+
     async def transcribe(
         self,
         audio_path: str,
         language: Optional[str] = None,
+        model_size: Optional[str] = None,
     ) -> str:
         """
         Transcribe audio to text.
-        
+
         Args:
             audio_path: Path to audio file
-            language: Optional language hint (en or zh)
+            language: Optional language hint
-            
+            model_size: Optional model size override
+
         Returns:
             Transcribed text
         """
-        await self.load_model_async(None)
+        await self.load_model_async(model_size)
-        
+
         def _transcribe_sync():
             """Run synchronous transcription in thread pool."""
             # Load audio
             audio, sr = load_audio(audio_path, sample_rate=16000)
-            
+
             # Process audio
             inputs = self.processor(
                 audio,
@@ -598,7 +333,7 @@ class PyTorchSTTBackend:
                 return_tensors="pt",
             )
             inputs = inputs.to(self.device)
-            
+
             # Generate transcription
             # If language is provided, force it; otherwise let Whisper auto-detect
             generate_kwargs = {}
@@ -608,20 +343,20 @@ class PyTorchSTTBackend:
                     task="transcribe",
                 )
                 generate_kwargs["forced_decoder_ids"] = forced_decoder_ids
-            
+
             with torch.no_grad():
                 predicted_ids = self.model.generate(
                     inputs["input_features"],
                     **generate_kwargs,
                 )
-            
+
             # Decode
             transcription = self.processor.batch_decode(
                 predicted_ids,
                 skip_special_tokens=True,
             )[0]
-            
+
             return transcription.strip()
-        
+
         # Run blocking transcription in thread pool
         return await asyncio.to_thread(_transcribe_sync)

backend/build_binary.py

@@ -8,11 +8,14 @@ Usage:
 
 import PyInstaller.__main__
 import argparse
+import logging
 import os
 import platform
 import sys
 from pathlib import Path
 
+logger = logging.getLogger(__name__)
+
 
 def is_apple_silicon():
     """Check if running on Apple Silicon."""
@@ -28,134 +31,252 @@ def build_server(cuda=False):
     """
     backend_dir = Path(__file__).parent
 
-    binary_name = 'voicebox-server-cuda' if cuda else 'voicebox-server'
+    binary_name = "voicebox-server-cuda" if cuda else "voicebox-server"
 
     # PyInstaller arguments
     args = [
-        'server.py',  # Use server.py as entry point instead of main.py
+        "server.py",  # Use server.py as entry point instead of main.py
-        '--onefile',
+        "--onefile",
-        '--noconsole',  # No visible console window on Windows
+        "--name",
-        '--name', binary_name,
+        binary_name,
     ]
 
+    # Hide console window on Windows only. On macOS/Linux the sidecar needs
+    # stdout/stderr for Tauri to capture logs.
+    if platform.system() == "Windows":
+        args.append("--noconsole")
+
     # Add local qwen_tts path if specified (for editable installs)
-    qwen_tts_path = os.getenv('QWEN_TTS_PATH')
+    qwen_tts_path = os.getenv("QWEN_TTS_PATH")
     if qwen_tts_path and Path(qwen_tts_path).exists():
-        args.extend(['--paths', str(qwen_tts_path)])
+        args.extend(["--paths", str(qwen_tts_path)])
-        print(f"Using local qwen_tts source from: {qwen_tts_path}")
+        logger.info("Using local qwen_tts source from: %s", qwen_tts_path)
 
     # Add common hidden imports
-    args.extend([
+    args.extend(
-        '--hidden-import', 'backend',
+        [
-        '--hidden-import', 'backend.main',
+            "--hidden-import",
-        '--hidden-import', 'backend.config',
+            "backend",
-        '--hidden-import', 'backend.database',
+            "--hidden-import",
-        '--hidden-import', 'backend.models',
+            "backend.main",
-        '--hidden-import', 'backend.profiles',
+            "--hidden-import",
-        '--hidden-import', 'backend.history',
+            "backend.config",
-        '--hidden-import', 'backend.tts',
+            "--hidden-import",
-        '--hidden-import', 'backend.transcribe',
+            "backend.database",
-        '--hidden-import', 'backend.platform_detect',
+            "--hidden-import",
-        '--hidden-import', 'backend.backends',
+            "backend.models",
-        '--hidden-import', 'backend.backends.pytorch_backend',
+            "--hidden-import",
-        '--hidden-import', 'backend.utils.audio',
+            "backend.services.profiles",
-        '--hidden-import', 'backend.utils.cache',
+            "--hidden-import",
-        '--hidden-import', 'backend.utils.progress',
+            "backend.services.history",
-        '--hidden-import', 'backend.utils.hf_progress',
+            "--hidden-import",
-        '--hidden-import', 'backend.utils.validation',
+            "backend.services.tts",
-        '--hidden-import', 'backend.cuda_download',
+            "--hidden-import",
-        '--hidden-import', 'backend.effects',
+            "backend.services.transcribe",
-        '--hidden-import', 'backend.utils.effects',
+            "--hidden-import",
-        '--hidden-import', 'backend.versions',
+            "backend.utils.platform_detect",
-        '--hidden-import', 'pedalboard',
+            "--hidden-import",
-        '--hidden-import', 'chatterbox',
+            "backend.backends",
-        '--hidden-import', 'chatterbox.tts_turbo',
+            "--hidden-import",
-        '--hidden-import', 'chatterbox.mtl_tts',
+            "backend.backends.pytorch_backend",
-        '--hidden-import', 'backend.backends.chatterbox_backend',
+            "--hidden-import",
-        '--hidden-import', 'backend.backends.chatterbox_turbo_backend',
+            "backend.utils.audio",
-        '--hidden-import', 'backend.backends.luxtts_backend',
+            "--hidden-import",
-        '--hidden-import', 'zipvoice',
+            "backend.utils.cache",
-        '--hidden-import', 'zipvoice.luxvoice',
+            "--hidden-import",
-        '--collect-all', 'zipvoice',
+            "backend.utils.progress",
-        '--hidden-import', 'torch',
+            "--hidden-import",
-        '--hidden-import', 'transformers',
+            "backend.utils.hf_progress",
-        '--hidden-import', 'fastapi',
+            "--hidden-import",
-        '--hidden-import', 'uvicorn',
+            "backend.services.cuda",
-        '--hidden-import', 'sqlalchemy',
+            "--hidden-import",
-        '--hidden-import', 'librosa',
+            "backend.services.effects",
-        '--hidden-import', 'soundfile',
+            "--hidden-import",
-        '--hidden-import', 'qwen_tts',
+            "backend.utils.effects",
-        '--hidden-import', 'qwen_tts.inference',
+            "--hidden-import",
-        '--hidden-import', 'qwen_tts.inference.qwen3_tts_model',
+            "backend.services.versions",
-        '--hidden-import', 'qwen_tts.inference.qwen3_tts_tokenizer',
+            "--hidden-import",
-        '--hidden-import', 'qwen_tts.core',
+            "pedalboard",
-        '--hidden-import', 'qwen_tts.cli',
+            "--hidden-import",
-        '--copy-metadata', 'qwen-tts',
+            "chatterbox",
-        '--collect-submodules', 'qwen_tts',
+            "--hidden-import",
-        '--collect-data', 'qwen_tts',
+            "chatterbox.tts_turbo",
-        # Fix for pkg_resources and jaraco namespace packages
+            "--hidden-import",
-        '--hidden-import', 'pkg_resources.extern',
+            "chatterbox.mtl_tts",
-        '--collect-submodules', 'jaraco',
+            "--hidden-import",
-    ])
+            "backend.backends.chatterbox_backend",
+            "--hidden-import",
+            "backend.backends.chatterbox_turbo_backend",
+            "--hidden-import",
+            "backend.backends.luxtts_backend",
+            "--hidden-import",
+            "zipvoice",
+            "--hidden-import",
+            "zipvoice.luxvoice",
+            "--collect-all",
+            "zipvoice",
+            "--collect-all",
+            "linacodec",
+            "--hidden-import",
+            "torch",
+            "--hidden-import",
+            "transformers",
+            "--hidden-import",
+            "fastapi",
+            "--hidden-import",
+            "uvicorn",
+            "--hidden-import",
+            "sqlalchemy",
+            # librosa uses lazy_loader which generates .pyi stub files at
+            # install time and reads them at runtime to discover submodules.
+            # --hidden-import alone doesn't bundle the stubs, causing
+            # "Cannot load imports from non-existent stub" at runtime.
+            "--collect-all",
+            "lazy_loader",
+            "--collect-all",
+            "librosa",
+            "--hidden-import",
+            "soundfile",
+            "--hidden-import",
+            "qwen_tts",
+            "--hidden-import",
+            "qwen_tts.inference",
+            "--hidden-import",
+            "qwen_tts.inference.qwen3_tts_model",
+            "--hidden-import",
+            "qwen_tts.inference.qwen3_tts_tokenizer",
+            "--hidden-import",
+            "qwen_tts.core",
+            "--hidden-import",
+            "qwen_tts.cli",
+            "--copy-metadata",
+            "qwen-tts",
+            "--copy-metadata",
+            "requests",
+            "--copy-metadata",
+            "transformers",
+            "--copy-metadata",
+            "huggingface-hub",
+            "--copy-metadata",
+            "tokenizers",
+            "--copy-metadata",
+            "safetensors",
+            "--copy-metadata",
+            "tqdm",
+            "--hidden-import",
+            "requests",
+            "--collect-submodules",
+            "qwen_tts",
+            "--collect-data",
+            "qwen_tts",
+            # Fix for pkg_resources and jaraco namespace packages
+            "--hidden-import",
+            "pkg_resources.extern",
+            "--collect-submodules",
+            "jaraco",
+            # inflect uses typeguard @typechecked which calls inspect.getsource()
+            # at import time — needs .py source files, not just .pyc bytecode
+            "--collect-all",
+            "inflect",
+            # perth ships pretrained watermark model files (hparams.yaml, .pth.tar)
+            # in perth/perth_net/pretrained/ — needed by chatterbox at runtime
+            "--collect-all",
+            "perth",
+            # piper_phonemize ships espeak-ng-data/ (phoneme tables, language dicts)
+            # needed by LuxTTS for text-to-phoneme conversion
+            "--collect-all",
+            "piper_phonemize",
+        ]
+    )
 
     # Add CUDA-specific hidden imports
     if cuda:
-        print("Building with CUDA support")
+        logger.info("Building with CUDA support")
-        args.extend([
+        args.extend(
-            '--hidden-import', 'torch.cuda',
+            [
-            '--hidden-import', 'torch.backends.cudnn',
+                "--hidden-import",
-        ])
+                "torch.cuda",
+                "--hidden-import",
+                "torch.backends.cudnn",
+            ]
+        )
     else:
         # Exclude NVIDIA CUDA packages from CPU-only builds to keep binary small.
         # When building from a venv with CUDA torch installed, PyInstaller would
         # bundle ~3GB of NVIDIA shared libraries. We exclude both the Python
         # modules and the binary DLLs.
         nvidia_packages = [
-            'nvidia', 'nvidia.cublas', 'nvidia.cuda_cupti', 'nvidia.cuda_nvrtc',
+            "nvidia",
-            'nvidia.cuda_runtime', 'nvidia.cudnn', 'nvidia.cufft', 'nvidia.curand',
+            "nvidia.cublas",
-            'nvidia.cusolver', 'nvidia.cusparse', 'nvidia.nccl', 'nvidia.nvjitlink',
+            "nvidia.cuda_cupti",
-            'nvidia.nvtx',
+            "nvidia.cuda_nvrtc",
+            "nvidia.cuda_runtime",
+            "nvidia.cudnn",
+            "nvidia.cufft",
+            "nvidia.curand",
+            "nvidia.cusolver",
+            "nvidia.cusparse",
+            "nvidia.nccl",
+            "nvidia.nvjitlink",
+            "nvidia.nvtx",
         ]
         for pkg in nvidia_packages:
-            args.extend(['--exclude-module', pkg])
+            args.extend(["--exclude-module", pkg])
 
     # Add MLX-specific imports if building on Apple Silicon (never for CUDA builds)
     if is_apple_silicon() and not cuda:
-        print("Building for Apple Silicon - including MLX dependencies")
+        logger.info("Building for Apple Silicon - including MLX dependencies")
-        args.extend([
+        args.extend(
-            '--hidden-import', 'backend.backends.mlx_backend',
+            [
-            '--hidden-import', 'mlx',
+                "--hidden-import",
-            '--hidden-import', 'mlx.core',
+                "backend.backends.mlx_backend",
-            '--hidden-import', 'mlx.nn',
+                "--hidden-import",
-            '--hidden-import', 'mlx_audio',
+                "mlx",
-            '--hidden-import', 'mlx_audio.tts',
+                "--hidden-import",
-            '--hidden-import', 'mlx_audio.stt',
+                "mlx.core",
-            '--collect-submodules', 'mlx',
+                "--hidden-import",
-            '--collect-submodules', 'mlx_audio',
+                "mlx.nn",
-            # Use --collect-all so PyInstaller bundles both data files AND
+                "--hidden-import",
-            # native shared libraries (.dylib, .metallib) for MLX.
+                "mlx_audio",
-            # Previously only --collect-data was used, which caused MLX to
+                "--hidden-import",
-            # raise OSError at runtime inside the bundled binary because
+                "mlx_audio.tts",
-            # the Metal shader libraries were missing.
+                "--hidden-import",
-            '--collect-all', 'mlx',
+                "mlx_audio.stt",
-            '--collect-all', 'mlx_audio',
+                "--collect-submodules",
-        ])
+                "mlx",
+                "--collect-submodules",
+                "mlx_audio",
+                # Use --collect-all so PyInstaller bundles both data files AND
+                # native shared libraries (.dylib, .metallib) for MLX.
+                # Previously only --collect-data was used, which caused MLX to
+                # raise OSError at runtime inside the bundled binary because
+                # the Metal shader libraries were missing.
+                "--collect-all",
+                "mlx",
+                "--collect-all",
+                "mlx_audio",
+            ]
+        )
     elif not cuda:
-        print("Building for non-Apple Silicon platform - PyTorch only")
+        logger.info("Building for non-Apple Silicon platform - PyTorch only")
 
-    dist_dir = str(backend_dir / 'dist')
+    dist_dir = str(backend_dir / "dist")
-    build_dir = str(backend_dir / 'build')
+    build_dir = str(backend_dir / "build")
 
-    args.extend([
+    args.extend(
-        '--distpath', dist_dir,
+        [
-        '--workpath', build_dir,
+            "--distpath",
-        '--noconfirm',
+            dist_dir,
-        '--clean',
+            "--workpath",
-    ])
+            build_dir,
+            "--noconfirm",
+            "--clean",
+        ]
+    )
 
     # Change to backend directory
     os.chdir(backend_dir)
-    
+
     # For CPU builds on Windows, ensure we're using CPU-only torch.
     # If CUDA torch is installed (local dev), swap to CPU torch before building,
     # then restore CUDA torch after. This prevents PyInstaller from bundling
@@ -163,17 +284,28 @@ def build_server(cuda=False):
     restore_cuda = False
     if not cuda and platform.system() == "Windows":
         import subprocess
+
         result = subprocess.run(
-            [sys.executable, "-c", "import torch; print(torch.version.cuda or '')"],
+            [sys.executable, "-c", "import torch; print(torch.version.cuda or '')"], capture_output=True, text=True
-            capture_output=True, text=True
         )
         has_cuda_torch = bool(result.stdout.strip())
         if has_cuda_torch:
-            print("CUDA torch detected — installing CPU torch for CPU build...")
+            logger.info("CUDA torch detected — installing CPU torch for CPU build...")
             subprocess.run(
-                [sys.executable, "-m", "pip", "install", "torch", "torchvision", "torchaudio",
+                [
-                 "--index-url", "https://download.pytorch.org/whl/cpu", "--force-reinstall", "-q"],
+                    sys.executable,
-                check=True
+                    "-m",
+                    "pip",
+                    "install",
+                    "torch",
+                    "torchvision",
+                    "torchaudio",
+                    "--index-url",
+                    "https://download.pytorch.org/whl/cpu",
+                    "--force-reinstall",
+                    "-q",
+                ],
+                check=True,
             )
             restore_cuda = True
 
@@ -183,57 +315,34 @@ def build_server(cuda=False):
     finally:
         # Restore CUDA torch if we swapped it out (even on build failure)
         if restore_cuda:
-            print("Restoring CUDA torch...")
+            logger.info("Restoring CUDA torch...")
             import subprocess
+
             subprocess.run(
-                [sys.executable, "-m", "pip", "install", "torch", "torchvision", "torchaudio",
+                [
-                 "--index-url", "https://download.pytorch.org/whl/cu126", "--force-reinstall", "-q"],
+                    sys.executable,
-                check=True
+                    "-m",
+                    "pip",
+                    "install",
+                    "torch",
+                    "torchvision",
+                    "torchaudio",
+                    "--index-url",
+                    "https://download.pytorch.org/whl/cu126",
+                    "--force-reinstall",
+                    "-q",
+                ],
+                check=True,
             )
-    
+
-    print(f"Binary built in {backend_dir / 'dist' / binary_name}")
+    logger.info("Binary built in %s", backend_dir / "dist" / binary_name)
 
 
-def _get_cuda_dll_excludes():
+if __name__ == "__main__":
-    """Get list of CUDA DLL filenames to exclude from CPU builds.
-    
-    When building locally with CUDA torch installed, PyInstaller bundles ~3GB of
-    CUDA DLLs from torch/lib/. Returns a list of DLL filenames to exclude.
-    """
-    try:
-        import torch
-        torch_lib = Path(torch.__file__).parent / 'lib'
-    except ImportError:
-        return []
-    
-    cuda_prefixes = (
-        'torch_cuda', 'cublas', 'cublasLt', 'cudnn', 'cusparse', 'cufft',
-        'cusolver', 'cusolverMg', 'curand', 'nvrtc', 'nvJitLink', 'nccl',
-        'nvperf', 'nvrtc-builtins',
-    )
-    
-    exclude_dlls = []
-    if torch_lib.exists():
-        for f in torch_lib.iterdir():
-            if f.suffix == '.dll' and any(f.name.startswith(p) for p in cuda_prefixes):
-                exclude_dlls.append(f.name)
-    
-    if exclude_dlls:
-        total_mb = sum(
-            (torch_lib / dll).stat().st_size 
-            for dll in exclude_dlls 
-            if (torch_lib / dll).exists()
-        ) / 1024 / 1024
-        print(f"CPU build: will exclude {len(exclude_dlls)} CUDA DLLs ({total_mb:.0f} MB)")
-    
-    return exclude_dlls
-
-
-if __name__ == '__main__':
     parser = argparse.ArgumentParser(description="Build voicebox-server binary")
     parser.add_argument(
-        '--cuda',
+        "--cuda",
-        action='store_true',
+        action="store_true",
         help="Build CUDA-enabled binary (voicebox-server-cuda)",
     )
     cli_args = parser.parse_args()

backend/config.py

@@ -4,20 +4,24 @@ Configuration module for voicebox backend.
 Handles data directory configuration for production bundling.
 """
 
+import logging
 import os
 from pathlib import Path
 
+logger = logging.getLogger(__name__)
+
 # Allow users to override the HuggingFace model download directory.
 # Set VOICEBOX_MODELS_DIR to an absolute path before starting the server.
 # This sets HF_HUB_CACHE so all huggingface_hub downloads go to that path.
 _custom_models_dir = os.environ.get("VOICEBOX_MODELS_DIR")
 if _custom_models_dir:
     os.environ["HF_HUB_CACHE"] = _custom_models_dir
-    print(f"[config] Model download path set to: {_custom_models_dir}")
+    logger.info("Model download path set to: %s", _custom_models_dir)
 
 # Default data directory (used in development)
 _data_dir = Path("data")
 
+
 def set_data_dir(path: str | Path):
     """
     Set the data directory path.
@@ -28,7 +32,8 @@ def set_data_dir(path: str | Path):
     global _data_dir
     _data_dir = Path(path)
     _data_dir.mkdir(parents=True, exist_ok=True)
-    print(f"Data directory set to: {_data_dir.absolute()}")
+    logger.info("Data directory set to: %s", _data_dir.absolute())
+
 
 def get_data_dir() -> Path:
     """
@@ -39,28 +44,33 @@ def get_data_dir() -> Path:
     """
     return _data_dir
 
+
 def get_db_path() -> Path:
     """Get database file path."""
     return _data_dir / "voicebox.db"
 
+
 def get_profiles_dir() -> Path:
     """Get profiles directory path."""
     path = _data_dir / "profiles"
     path.mkdir(parents=True, exist_ok=True)
     return path
 
+
 def get_generations_dir() -> Path:
     """Get generations directory path."""
     path = _data_dir / "generations"
     path.mkdir(parents=True, exist_ok=True)
     return path
 
+
 def get_cache_dir() -> Path:
     """Get cache directory path."""
     path = _data_dir / "cache"
     path.mkdir(parents=True, exist_ok=True)
     return path
 
+
 def get_models_dir() -> Path:
     """Get models directory path."""
     path = _data_dir / "models"

backend/database.py

@@ -1,487 +0,0 @@
-"""
-SQLite database ORM using SQLAlchemy.
-"""
-
-from sqlalchemy import create_engine, Column, String, Integer, Float, DateTime, Text, ForeignKey, Boolean
-from sqlalchemy.ext.declarative import declarative_base
-from sqlalchemy.orm import sessionmaker, Session
-from datetime import datetime
-import uuid
-from pathlib import Path
-
-from . import config
-
-Base = declarative_base()
-
-
-class VoiceProfile(Base):
-    """Voice profile database model."""
-    __tablename__ = "profiles"
-
-    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
-    name = Column(String, unique=True, nullable=False)
-    description = Column(Text)
-    language = Column(String, default="en")
-    avatar_path = Column(String, nullable=True)
-    effects_chain = Column(Text, nullable=True)  # JSON-serialized default effects chain
-    created_at = Column(DateTime, default=datetime.utcnow)
-    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
-
-
-class ProfileSample(Base):
-    """Voice profile sample database model."""
-    __tablename__ = "profile_samples"
-    
-    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
-    profile_id = Column(String, ForeignKey("profiles.id"), nullable=False)
-    audio_path = Column(String, nullable=False)
-    reference_text = Column(Text, nullable=False)
-
-
-class Generation(Base):
-    """Generation history database model."""
-    __tablename__ = "generations"
-
-    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
-    profile_id = Column(String, ForeignKey("profiles.id"), nullable=False)
-    text = Column(Text, nullable=False)
-    language = Column(String, default="en")
-    audio_path = Column(String, nullable=True)
-    duration = Column(Float, nullable=True)
-    seed = Column(Integer)
-    instruct = Column(Text)
-    engine = Column(String, default="qwen")
-    model_size = Column(String, nullable=True)
-    status = Column(String, default="completed")  # generating, completed, failed
-    error = Column(Text, nullable=True)
-    is_favorited = Column(Boolean, default=False)
-    created_at = Column(DateTime, default=datetime.utcnow)
-
-
-class Story(Base):
-    """Story database model."""
-    __tablename__ = "stories"
-    
-    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
-    name = Column(String, nullable=False)
-    description = Column(Text)
-    created_at = Column(DateTime, default=datetime.utcnow)
-    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
-
-
-class StoryItem(Base):
-    """Story item database model (links generations to stories)."""
-    __tablename__ = "story_items"
-    
-    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
-    story_id = Column(String, ForeignKey("stories.id"), nullable=False)
-    generation_id = Column(String, ForeignKey("generations.id"), nullable=False)
-    version_id = Column(String, ForeignKey("generation_versions.id"), nullable=True)  # Pin to specific version, null = use generation default
-    start_time_ms = Column(Integer, nullable=False, default=0)  # Milliseconds from story start
-    track = Column(Integer, nullable=False, default=0)  # Track number (0 = main track)
-    trim_start_ms = Column(Integer, nullable=False, default=0)  # Milliseconds trimmed from start
-    trim_end_ms = Column(Integer, nullable=False, default=0)  # Milliseconds trimmed from end
-    created_at = Column(DateTime, default=datetime.utcnow)
-
-
-class Project(Base):
-    """Audio studio project database model."""
-    __tablename__ = "projects"
-    
-    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
-    name = Column(String, nullable=False)
-    data = Column(Text)  # JSON string
-    created_at = Column(DateTime, default=datetime.utcnow)
-    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
-
-
-class GenerationVersion(Base):
-    """A version of a generation's audio (clean, processed, alternate takes)."""
-    __tablename__ = "generation_versions"
-
-    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
-    generation_id = Column(String, ForeignKey("generations.id"), nullable=False)
-    label = Column(String, nullable=False)  # "clean", "processed", or user-defined
-    audio_path = Column(String, nullable=False)
-    effects_chain = Column(Text, nullable=True)  # JSON-serialized effects config, null for clean
-    source_version_id = Column(String, ForeignKey("generation_versions.id"), nullable=True)  # Which version was used as input
-    is_default = Column(Boolean, default=False)
-    created_at = Column(DateTime, default=datetime.utcnow)
-
-
-class EffectPreset(Base):
-    """Saved effect chain preset."""
-    __tablename__ = "effect_presets"
-
-    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
-    name = Column(String, unique=True, nullable=False)
-    description = Column(Text, nullable=True)
-    effects_chain = Column(Text, nullable=False)  # JSON-serialized effects config
-    is_builtin = Column(Boolean, default=False)
-    sort_order = Column(Integer, default=100)
-    created_at = Column(DateTime, default=datetime.utcnow)
-
-
-class AudioChannel(Base):
-    """Audio channel (bus) database model."""
-    __tablename__ = "audio_channels"
-    
-    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
-    name = Column(String, nullable=False)
-    is_default = Column(Boolean, default=False)
-    created_at = Column(DateTime, default=datetime.utcnow)
-
-
-class ChannelDeviceMapping(Base):
-    """Mapping between channels and OS audio devices."""
-    __tablename__ = "channel_device_mappings"
-    
-    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
-    channel_id = Column(String, ForeignKey("audio_channels.id"), nullable=False)
-    device_id = Column(String, nullable=False)  # OS device identifier
-
-
-class ProfileChannelMapping(Base):
-    """Mapping between voice profiles and audio channels (many-to-many)."""
-    __tablename__ = "profile_channel_mappings"
-    
-    profile_id = Column(String, ForeignKey("profiles.id"), primary_key=True)
-    channel_id = Column(String, ForeignKey("audio_channels.id"), primary_key=True)
-
-
-# Database setup will be initialized in init_db()
-engine = None
-SessionLocal = None
-_db_path = None
-
-
-def init_db():
-    """Initialize database tables."""
-    global engine, SessionLocal, _db_path
-
-    _db_path = config.get_db_path()
-    _db_path.parent.mkdir(parents=True, exist_ok=True)
-
-    engine = create_engine(
-        f"sqlite:///{_db_path}",
-        connect_args={"check_same_thread": False},
-    )
-
-    SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
-    
-    # Run migrations before creating tables
-    _run_migrations(engine)
-    
-    Base.metadata.create_all(bind=engine)
-    
-    # Create default channel if it doesn't exist
-    db = SessionLocal()
-    try:
-        default_channel = db.query(AudioChannel).filter(AudioChannel.is_default == True).first()
-        if not default_channel:
-            default_channel = AudioChannel(
-                id=str(uuid.uuid4()),
-                name="Default",
-                is_default=True
-            )
-            db.add(default_channel)
-            
-            # Assign all existing profiles to default channel
-            profiles = db.query(VoiceProfile).all()
-            for profile in profiles:
-                mapping = ProfileChannelMapping(
-                    profile_id=profile.id,
-                    channel_id=default_channel.id
-                )
-                db.add(mapping)
-            
-            db.commit()
-    finally:
-        db.close()
-
-    # Backfill: create "clean" GenerationVersion entries for existing generations
-    _backfill_generation_versions()
-
-    # Seed built-in effect presets
-    _seed_builtin_presets()
-
-
-def _run_migrations(engine):
-    """Run database migrations."""
-    from sqlalchemy import inspect, text
-    
-    inspector = inspect(engine)
-    
-    # Check if story_items table exists
-    if 'story_items' not in inspector.get_table_names():
-        return  # Table doesn't exist yet, will be created fresh
-    
-    # Get columns in story_items table
-    columns = {col['name'] for col in inspector.get_columns('story_items')}
-    
-    # Migration: Remove position column and ensure start_time_ms exists
-    # SQLite doesn't support DROP COLUMN easily, so we recreate the table
-    if 'position' in columns:
-        print("Migrating story_items: removing position column, using start_time_ms")
-        
-        with engine.connect() as conn:
-            # Check if start_time_ms already exists
-            has_start_time = 'start_time_ms' in columns
-            
-            if not has_start_time:
-                # First, add the new column temporarily
-                conn.execute(text("ALTER TABLE story_items ADD COLUMN start_time_ms INTEGER DEFAULT 0"))
-                
-                # Calculate timecodes from position ordering
-                result = conn.execute(text("""
-                    SELECT si.id, si.story_id, si.position, g.duration
-                    FROM story_items si
-                    JOIN generations g ON si.generation_id = g.id
-                    ORDER BY si.story_id, si.position
-                """))
-                
-                rows = result.fetchall()
-                
-                current_story_id = None
-                current_time_ms = 0
-                
-                for row in rows:
-                    item_id, story_id, position, duration = row
-                    
-                    if story_id != current_story_id:
-                        current_story_id = story_id
-                        current_time_ms = 0
-                    
-                    conn.execute(
-                        text("UPDATE story_items SET start_time_ms = :time WHERE id = :id"),
-                        {"time": current_time_ms, "id": item_id}
-                    )
-                    
-                    current_time_ms += int(duration * 1000) + 200
-                
-                conn.commit()
-            
-            # Now recreate the table without the position column
-            # 1. Create new table
-            conn.execute(text("""
-                CREATE TABLE story_items_new (
-                    id VARCHAR PRIMARY KEY,
-                    story_id VARCHAR NOT NULL,
-                    generation_id VARCHAR NOT NULL,
-                    start_time_ms INTEGER NOT NULL DEFAULT 0,
-                    created_at DATETIME,
-                    FOREIGN KEY (story_id) REFERENCES stories(id),
-                    FOREIGN KEY (generation_id) REFERENCES generations(id)
-                )
-            """))
-            
-            # 2. Copy data
-            conn.execute(text("""
-                INSERT INTO story_items_new (id, story_id, generation_id, start_time_ms, created_at)
-                SELECT id, story_id, generation_id, start_time_ms, created_at FROM story_items
-            """))
-            
-            # 3. Drop old table
-            conn.execute(text("DROP TABLE story_items"))
-            
-            # 4. Rename new table
-            conn.execute(text("ALTER TABLE story_items_new RENAME TO story_items"))
-            
-            conn.commit()
-            print("Migrated story_items table to use start_time_ms (removed position column)")
-    
-    # Migration: Add track column if it doesn't exist
-    # Re-check columns after potential position migration
-    columns = {col['name'] for col in inspector.get_columns('story_items')}
-    if 'track' not in columns:
-        print("Migrating story_items: adding track column")
-        with engine.connect() as conn:
-            conn.execute(text("ALTER TABLE story_items ADD COLUMN track INTEGER NOT NULL DEFAULT 0"))
-            conn.commit()
-            print("Added track column to story_items")
-    
-    # Migration: Add trim columns if they don't exist
-    # Re-check columns after potential track migration
-    columns = {col['name'] for col in inspector.get_columns('story_items')}
-    if 'trim_start_ms' not in columns:
-        print("Migrating story_items: adding trim_start_ms column")
-        with engine.connect() as conn:
-            conn.execute(text("ALTER TABLE story_items ADD COLUMN trim_start_ms INTEGER NOT NULL DEFAULT 0"))
-            conn.commit()
-            print("Added trim_start_ms column to story_items")
-    
-    columns = {col['name'] for col in inspector.get_columns('story_items')}
-    if 'trim_end_ms' not in columns:
-        print("Migrating story_items: adding trim_end_ms column")
-        with engine.connect() as conn:
-            conn.execute(text("ALTER TABLE story_items ADD COLUMN trim_end_ms INTEGER NOT NULL DEFAULT 0"))
-            conn.commit()
-            print("Added trim_end_ms column to story_items")
-
-    # Migration: Add avatar_path to profiles table
-    if 'profiles' in inspector.get_table_names():
-        columns = {col['name'] for col in inspector.get_columns('profiles')}
-        if 'avatar_path' not in columns:
-            print("Migrating profiles: adding avatar_path column")
-            with engine.connect() as conn:
-                conn.execute(text("ALTER TABLE profiles ADD COLUMN avatar_path VARCHAR"))
-                conn.commit()
-                print("Added avatar_path column to profiles")
-
-    # Migration: Add status and error columns to generations table
-    if 'generations' in inspector.get_table_names():
-        columns = {col['name'] for col in inspector.get_columns('generations')}
-        if 'status' not in columns:
-            print("Migrating generations: adding status column")
-            with engine.connect() as conn:
-                conn.execute(text("ALTER TABLE generations ADD COLUMN status VARCHAR DEFAULT 'completed'"))
-                conn.commit()
-                print("Added status column to generations")
-        if 'error' not in columns:
-            print("Migrating generations: adding error column")
-            with engine.connect() as conn:
-                conn.execute(text("ALTER TABLE generations ADD COLUMN error TEXT"))
-                conn.commit()
-                print("Added error column to generations")
-        if 'engine' not in columns:
-            print("Migrating generations: adding engine column")
-            with engine.connect() as conn:
-                conn.execute(text("ALTER TABLE generations ADD COLUMN engine VARCHAR DEFAULT 'qwen'"))
-                conn.commit()
-                print("Added engine column to generations")
-        # Re-read columns after engine migration (variable name shadows outer `engine`)
-        columns = {col['name'] for col in inspector.get_columns('generations')}
-        if 'model_size' not in columns:
-            print("Migrating generations: adding model_size column")
-            with engine.connect() as conn:
-                conn.execute(text("ALTER TABLE generations ADD COLUMN model_size VARCHAR"))
-                conn.commit()
-                print("Added model_size column to generations")
-
-    # Migration: Add effects_chain to profiles table
-    if 'profiles' in inspector.get_table_names():
-        columns = {col['name'] for col in inspector.get_columns('profiles')}
-        if 'effects_chain' not in columns:
-            print("Migrating profiles: adding effects_chain column")
-            with engine.connect() as conn:
-                conn.execute(text("ALTER TABLE profiles ADD COLUMN effects_chain TEXT"))
-                conn.commit()
-                print("Added effects_chain column to profiles")
-
-    # Migration: Add sort_order to effect_presets table
-    if 'effect_presets' in inspector.get_table_names():
-        columns = {col['name'] for col in inspector.get_columns('effect_presets')}
-        if 'sort_order' not in columns:
-            print("Migrating effect_presets: adding sort_order column")
-            with engine.connect() as conn:
-                conn.execute(text("ALTER TABLE effect_presets ADD COLUMN sort_order INTEGER DEFAULT 100"))
-                conn.commit()
-                print("Added sort_order column to effect_presets")
-
-    # Migration: Add version_id column to story_items table
-    if 'story_items' in inspector.get_table_names():
-        columns = {col['name'] for col in inspector.get_columns('story_items')}
-        if 'version_id' not in columns:
-            print("Migrating story_items: adding version_id column")
-            with engine.connect() as conn:
-                conn.execute(text("ALTER TABLE story_items ADD COLUMN version_id VARCHAR"))
-                conn.commit()
-                print("Added version_id column to story_items")
-
-    # Migration: Add source_version_id to generation_versions table
-    if 'generation_versions' in inspector.get_table_names():
-        columns = {col['name'] for col in inspector.get_columns('generation_versions')}
-        if 'source_version_id' not in columns:
-            print("Migrating generation_versions: adding source_version_id column")
-            with engine.connect() as conn:
-                conn.execute(text("ALTER TABLE generation_versions ADD COLUMN source_version_id VARCHAR"))
-                conn.commit()
-                print("Added source_version_id column to generation_versions")
-
-    if 'generations' in inspector.get_table_names():
-        columns = {col['name'] for col in inspector.get_columns('generations')}
-        if 'is_favorited' not in columns:
-            print("Migrating generations: adding is_favorited column")
-            with engine.connect() as conn:
-                conn.execute(text("ALTER TABLE generations ADD COLUMN is_favorited BOOLEAN DEFAULT 0"))
-                conn.commit()
-                print("Added is_favorited column to generations")
-
-    # Migration: Create generation_versions for existing generations
-    # (populate after tables are created, handled in init_db)
-
-
-def _backfill_generation_versions():
-    """Create 'clean' version entries for existing generations that don't have any."""
-    db = SessionLocal()
-    try:
-        from pathlib import Path as _Path
-
-        # Find generations that have no version entries
-        existing_version_gen_ids = {
-            row[0] for row in db.query(GenerationVersion.generation_id).all()
-        }
-        generations = db.query(Generation).filter(
-            Generation.status == "completed",
-            Generation.audio_path.isnot(None),
-            Generation.audio_path != "",
-        ).all()
-
-        count = 0
-        for gen in generations:
-            if gen.id in existing_version_gen_ids:
-                continue
-            if not _Path(gen.audio_path).exists():
-                continue
-            version = GenerationVersion(
-                id=str(uuid.uuid4()),
-                generation_id=gen.id,
-                label="clean",
-                audio_path=gen.audio_path,
-                effects_chain=None,
-                is_default=True,
-            )
-            db.add(version)
-            count += 1
-
-        if count > 0:
-            db.commit()
-            print(f"Backfilled {count} generation version entries")
-    finally:
-        db.close()
-
-
-def _seed_builtin_presets():
-    """Ensure built-in effect presets exist in the database."""
-    import json
-    from .utils.effects import BUILTIN_PRESETS
-
-    db = SessionLocal()
-    try:
-        for idx, (key, preset_data) in enumerate(BUILTIN_PRESETS.items()):
-            sort_order = preset_data.get("sort_order", idx)
-            existing = db.query(EffectPreset).filter_by(name=preset_data["name"]).first()
-            if not existing:
-                preset = EffectPreset(
-                    id=str(uuid.uuid4()),
-                    name=preset_data["name"],
-                    description=preset_data.get("description"),
-                    effects_chain=json.dumps(preset_data["effects_chain"]),
-                    is_builtin=True,
-                    sort_order=sort_order,
-                )
-                db.add(preset)
-            elif existing.sort_order != sort_order:
-                existing.sort_order = sort_order
-        db.commit()
-    finally:
-        db.close()
-
-
-def get_db():
-    """Get database session (generator for dependency injection)."""
-    db = SessionLocal()
-    try:
-        yield db
-    finally:
-        db.close()

backend/database/__init__.py

@@ -0,0 +1,44 @@
+"""Database package — ORM models, session management, and migrations.
+
+Re-exports all public symbols so that ``from .database import get_db``
+and ``from .database import Generation as DBGeneration`` continue to work
+without changing any importers.
+"""
+
+from .models import (
+    Base,
+    AudioChannel,
+    ChannelDeviceMapping,
+    EffectPreset,
+    Generation,
+    GenerationVersion,
+    ProfileChannelMapping,
+    ProfileSample,
+    Project,
+    Story,
+    StoryItem,
+    VoiceProfile,
+)
+from .session import engine, SessionLocal, _db_path, init_db, get_db
+
+__all__ = [
+    # Models
+    "Base",
+    "AudioChannel",
+    "ChannelDeviceMapping",
+    "EffectPreset",
+    "Generation",
+    "GenerationVersion",
+    "ProfileChannelMapping",
+    "ProfileSample",
+    "Project",
+    "Story",
+    "StoryItem",
+    "VoiceProfile",
+    # Session
+    "engine",
+    "SessionLocal",
+    "_db_path",
+    "init_db",
+    "get_db",
+]

backend/database/migrations.py

@@ -0,0 +1,170 @@
+"""Column-level migrations for the voicebox SQLite database.
+
+Why not Alembic?  voicebox is a single-user desktop app shipping as a
+PyInstaller binary.  Every user has exactly one SQLite file.  Alembic's
+strengths -- migration tracking across environments, rollback, team
+coordination -- don't apply here and would add bundling complexity
+(alembic.ini, env.py, versions/ directory all need to survive
+PyInstaller).  The column-existence checks below are idempotent, run in
+<50 ms on startup, and have worked reliably across 12 schema changes.
+If the project ever moves to a server-based deployment or Postgres, this
+decision should be revisited.
+
+Adding a new migration:
+    1. Append a new ``_migrate_*`` helper at the bottom of this file.
+    2. Call it from ``run_migrations()`` in the appropriate spot.
+    3. The helper should check column/table existence before acting
+       (idempotent) and print a short message when it does real work.
+"""
+
+import logging
+
+from sqlalchemy import inspect, text
+
+logger = logging.getLogger(__name__)
+
+
+def run_migrations(engine) -> None:
+    """Run all schema migrations.  Safe to call on every startup."""
+    inspector = inspect(engine)
+    tables = set(inspector.get_table_names())
+
+    _migrate_story_items(engine, inspector, tables)
+    _migrate_profiles(engine, inspector, tables)
+    _migrate_generations(engine, inspector, tables)
+    _migrate_effect_presets(engine, inspector, tables)
+    _migrate_generation_versions(engine, inspector, tables)
+
+
+# -- helpers ---------------------------------------------------------------
+
+def _get_columns(inspector, table: str) -> set[str]:
+    return {col["name"] for col in inspector.get_columns(table)}
+
+
+def _add_column(engine, table: str, column_sql: str, label: str) -> None:
+    """Add a column if it doesn't already exist."""
+    with engine.connect() as conn:
+        conn.execute(text(f"ALTER TABLE {table} ADD COLUMN {column_sql}"))
+        conn.commit()
+    logger.info("Added %s column to %s", label, table)
+
+
+# -- per-table migrations --------------------------------------------------
+
+def _migrate_story_items(engine, inspector, tables: set[str]) -> None:
+    if "story_items" not in tables:
+        return
+
+    columns = _get_columns(inspector, "story_items")
+
+    # Replace position-based ordering with absolute timecodes
+    if "position" in columns:
+        logger.info("Migrating story_items: removing position column, using start_time_ms")
+        with engine.connect() as conn:
+            if "start_time_ms" not in columns:
+                conn.execute(text(
+                    "ALTER TABLE story_items ADD COLUMN start_time_ms INTEGER DEFAULT 0"
+                ))
+                result = conn.execute(text("""
+                    SELECT si.id, si.story_id, si.position, g.duration
+                    FROM story_items si
+                    JOIN generations g ON si.generation_id = g.id
+                    ORDER BY si.story_id, si.position
+                """))
+                current_story_id = None
+                current_time_ms = 0
+                for item_id, story_id, _position, duration in result.fetchall():
+                    if story_id != current_story_id:
+                        current_story_id = story_id
+                        current_time_ms = 0
+                    conn.execute(
+                        text("UPDATE story_items SET start_time_ms = :time WHERE id = :id"),
+                        {"time": current_time_ms, "id": item_id},
+                    )
+                    current_time_ms += int((duration or 0) * 1000) + 200
+                conn.commit()
+
+            # Recreate table without the position column (SQLite lacks DROP COLUMN)
+            conn.execute(text("""
+                CREATE TABLE story_items_new (
+                    id VARCHAR PRIMARY KEY,
+                    story_id VARCHAR NOT NULL,
+                    generation_id VARCHAR NOT NULL,
+                    start_time_ms INTEGER NOT NULL DEFAULT 0,
+                    track INTEGER NOT NULL DEFAULT 0,
+                    trim_start_ms INTEGER NOT NULL DEFAULT 0,
+                    trim_end_ms INTEGER NOT NULL DEFAULT 0,
+                    version_id VARCHAR,
+                    created_at DATETIME,
+                    FOREIGN KEY (story_id) REFERENCES stories(id),
+                    FOREIGN KEY (generation_id) REFERENCES generations(id)
+                )
+            """))
+            conn.execute(text("""
+                INSERT INTO story_items_new (id, story_id, generation_id, start_time_ms, track, trim_start_ms, trim_end_ms, version_id, created_at)
+                SELECT id, story_id, generation_id, start_time_ms,
+                    COALESCE(track, 0), COALESCE(trim_start_ms, 0), COALESCE(trim_end_ms, 0), version_id, created_at
+                FROM story_items
+            """))
+            conn.execute(text("DROP TABLE story_items"))
+            conn.execute(text("ALTER TABLE story_items_new RENAME TO story_items"))
+            conn.commit()
+
+        # Re-read after table recreation
+        columns = _get_columns(inspector, "story_items")
+
+    if "track" not in columns:
+        _add_column(engine, "story_items", "track INTEGER NOT NULL DEFAULT 0", "track")
+    # Re-read so subsequent checks see new columns
+    columns = _get_columns(inspector, "story_items")
+    if "trim_start_ms" not in columns:
+        _add_column(engine, "story_items", "trim_start_ms INTEGER NOT NULL DEFAULT 0", "trim_start_ms")
+    if "trim_end_ms" not in columns:
+        _add_column(engine, "story_items", "trim_end_ms INTEGER NOT NULL DEFAULT 0", "trim_end_ms")
+    if "version_id" not in columns:
+        _add_column(engine, "story_items", "version_id VARCHAR", "version_id")
+
+
+def _migrate_profiles(engine, inspector, tables: set[str]) -> None:
+    if "profiles" not in tables:
+        return
+    columns = _get_columns(inspector, "profiles")
+    if "avatar_path" not in columns:
+        _add_column(engine, "profiles", "avatar_path VARCHAR", "avatar_path")
+    if "effects_chain" not in columns:
+        _add_column(engine, "profiles", "effects_chain TEXT", "effects_chain")
+
+
+def _migrate_generations(engine, inspector, tables: set[str]) -> None:
+    if "generations" not in tables:
+        return
+    columns = _get_columns(inspector, "generations")
+    if "status" not in columns:
+        _add_column(engine, "generations", "status VARCHAR DEFAULT 'completed'", "status")
+    if "error" not in columns:
+        _add_column(engine, "generations", "error TEXT", "error")
+    if "engine" not in columns:
+        _add_column(engine, "generations", "engine VARCHAR DEFAULT 'qwen'", "engine")
+    # Re-read after engine column (variable name shadows outer scope in old code)
+    columns = _get_columns(inspector, "generations")
+    if "model_size" not in columns:
+        _add_column(engine, "generations", "model_size VARCHAR", "model_size")
+    if "is_favorited" not in columns:
+        _add_column(engine, "generations", "is_favorited BOOLEAN DEFAULT 0", "is_favorited")
+
+
+def _migrate_effect_presets(engine, inspector, tables: set[str]) -> None:
+    if "effect_presets" not in tables:
+        return
+    columns = _get_columns(inspector, "effect_presets")
+    if "sort_order" not in columns:
+        _add_column(engine, "effect_presets", "sort_order INTEGER DEFAULT 100", "sort_order")
+
+
+def _migrate_generation_versions(engine, inspector, tables: set[str]) -> None:
+    if "generation_versions" not in tables:
+        return
+    columns = _get_columns(inspector, "generation_versions")
+    if "source_version_id" not in columns:
+        _add_column(engine, "generation_versions", "source_version_id VARCHAR", "source_version_id")

backend/database/models.py

@@ -0,0 +1,155 @@
+"""ORM model definitions for the voicebox SQLite database."""
+
+from datetime import datetime
+import uuid
+
+from sqlalchemy import Column, String, Integer, Float, DateTime, Text, ForeignKey, Boolean
+from sqlalchemy.ext.declarative import declarative_base
+
+Base = declarative_base()
+
+
+class VoiceProfile(Base):
+    """Voice profile."""
+
+    __tablename__ = "profiles"
+
+    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
+    name = Column(String, unique=True, nullable=False)
+    description = Column(Text)
+    language = Column(String, default="en")
+    avatar_path = Column(String, nullable=True)
+    effects_chain = Column(Text, nullable=True)
+    created_at = Column(DateTime, default=datetime.utcnow)
+    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+
+
+class ProfileSample(Base):
+    """Audio sample attached to a voice profile."""
+
+    __tablename__ = "profile_samples"
+
+    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
+    profile_id = Column(String, ForeignKey("profiles.id"), nullable=False)
+    audio_path = Column(String, nullable=False)
+    reference_text = Column(Text, nullable=False)
+
+
+class Generation(Base):
+    """A single TTS generation."""
+
+    __tablename__ = "generations"
+
+    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
+    profile_id = Column(String, ForeignKey("profiles.id"), nullable=False)
+    text = Column(Text, nullable=False)
+    language = Column(String, default="en")
+    audio_path = Column(String, nullable=True)
+    duration = Column(Float, nullable=True)
+    seed = Column(Integer)
+    instruct = Column(Text)
+    engine = Column(String, default="qwen")
+    model_size = Column(String, nullable=True)
+    status = Column(String, default="completed")
+    error = Column(Text, nullable=True)
+    is_favorited = Column(Boolean, default=False)
+    created_at = Column(DateTime, default=datetime.utcnow)
+
+
+class Story(Base):
+    """A story that sequences multiple generations."""
+
+    __tablename__ = "stories"
+
+    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
+    name = Column(String, nullable=False)
+    description = Column(Text)
+    created_at = Column(DateTime, default=datetime.utcnow)
+    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+
+
+class StoryItem(Base):
+    """Links a generation to a story at a specific timecode."""
+
+    __tablename__ = "story_items"
+
+    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
+    story_id = Column(String, ForeignKey("stories.id"), nullable=False)
+    generation_id = Column(String, ForeignKey("generations.id"), nullable=False)
+    version_id = Column(String, ForeignKey("generation_versions.id"), nullable=True)
+    start_time_ms = Column(Integer, nullable=False, default=0)
+    track = Column(Integer, nullable=False, default=0)
+    trim_start_ms = Column(Integer, nullable=False, default=0)
+    trim_end_ms = Column(Integer, nullable=False, default=0)
+    created_at = Column(DateTime, default=datetime.utcnow)
+
+
+class Project(Base):
+    """Audio studio project (JSON blob)."""
+
+    __tablename__ = "projects"
+
+    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
+    name = Column(String, nullable=False)
+    data = Column(Text)
+    created_at = Column(DateTime, default=datetime.utcnow)
+    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+
+
+class GenerationVersion(Base):
+    """A version of a generation's audio (original, processed, alternate takes)."""
+
+    __tablename__ = "generation_versions"
+
+    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
+    generation_id = Column(String, ForeignKey("generations.id"), nullable=False)
+    label = Column(String, nullable=False)
+    audio_path = Column(String, nullable=False)
+    effects_chain = Column(Text, nullable=True)
+    source_version_id = Column(String, ForeignKey("generation_versions.id"), nullable=True)
+    is_default = Column(Boolean, default=False)
+    created_at = Column(DateTime, default=datetime.utcnow)
+
+
+class EffectPreset(Base):
+    """Saved effect chain preset."""
+
+    __tablename__ = "effect_presets"
+
+    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
+    name = Column(String, unique=True, nullable=False)
+    description = Column(Text, nullable=True)
+    effects_chain = Column(Text, nullable=False)
+    is_builtin = Column(Boolean, default=False)
+    sort_order = Column(Integer, default=100)
+    created_at = Column(DateTime, default=datetime.utcnow)
+
+
+class AudioChannel(Base):
+    """Audio output channel (bus)."""
+
+    __tablename__ = "audio_channels"
+
+    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
+    name = Column(String, nullable=False)
+    is_default = Column(Boolean, default=False)
+    created_at = Column(DateTime, default=datetime.utcnow)
+
+
+class ChannelDeviceMapping(Base):
+    """Mapping between a channel and an OS audio device."""
+
+    __tablename__ = "channel_device_mappings"
+
+    id = Column(String, primary_key=True, default=lambda: str(uuid.uuid4()))
+    channel_id = Column(String, ForeignKey("audio_channels.id"), nullable=False)
+    device_id = Column(String, nullable=False)
+
+
+class ProfileChannelMapping(Base):
+    """Many-to-many mapping between voice profiles and audio channels."""
+
+    __tablename__ = "profile_channel_mappings"
+
+    profile_id = Column(String, ForeignKey("profiles.id"), primary_key=True)
+    channel_id = Column(String, ForeignKey("audio_channels.id"), primary_key=True)

backend/database/seed.py

@@ -0,0 +1,71 @@
+"""Post-migration data seeding and backfills."""
+
+import json
+import logging
+import uuid
+from pathlib import Path
+
+logger = logging.getLogger(__name__)
+
+
+def backfill_generation_versions(SessionLocal, Generation, GenerationVersion) -> None:
+    """Create 'clean' version entries for generations that predate the versions feature."""
+    db = SessionLocal()
+    try:
+        existing_version_gen_ids = {
+            row[0] for row in db.query(GenerationVersion.generation_id).all()
+        }
+        generations = db.query(Generation).filter(
+            Generation.status == "completed",
+            Generation.audio_path.isnot(None),
+            Generation.audio_path != "",
+        ).all()
+
+        count = 0
+        for gen in generations:
+            if gen.id in existing_version_gen_ids:
+                continue
+            if not Path(gen.audio_path).exists():
+                continue
+            version = GenerationVersion(
+                id=str(uuid.uuid4()),
+                generation_id=gen.id,
+                label="clean",
+                audio_path=gen.audio_path,
+                effects_chain=None,
+                is_default=True,
+            )
+            db.add(version)
+            count += 1
+
+        if count > 0:
+            db.commit()
+            logger.info("Backfilled %d generation version entries", count)
+    finally:
+        db.close()
+
+
+def seed_builtin_presets(SessionLocal, EffectPreset) -> None:
+    """Ensure built-in effect presets exist in the database."""
+    from ..utils.effects import BUILTIN_PRESETS
+
+    db = SessionLocal()
+    try:
+        for idx, (_key, preset_data) in enumerate(BUILTIN_PRESETS.items()):
+            sort_order = preset_data.get("sort_order", idx)
+            existing = db.query(EffectPreset).filter_by(name=preset_data["name"]).first()
+            if not existing:
+                preset = EffectPreset(
+                    id=str(uuid.uuid4()),
+                    name=preset_data["name"],
+                    description=preset_data.get("description"),
+                    effects_chain=json.dumps(preset_data["effects_chain"]),
+                    is_builtin=True,
+                    sort_order=sort_order,
+                )
+                db.add(preset)
+            elif existing.sort_order != sort_order:
+                existing.sort_order = sort_order
+        db.commit()
+    finally:
+        db.close()

backend/database/session.py

@@ -0,0 +1,78 @@
+"""Engine creation, initialization, and session management."""
+
+import logging
+import uuid
+
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+
+from .. import config
+from .models import (
+    Base,
+    AudioChannel,
+    EffectPreset,
+    Generation,
+    GenerationVersion,
+    ProfileChannelMapping,
+    VoiceProfile,
+)
+from .migrations import run_migrations
+from .seed import backfill_generation_versions, seed_builtin_presets
+
+logger = logging.getLogger(__name__)
+
+# Initialized by init_db()
+engine = None
+SessionLocal = None
+_db_path = None
+
+
+def init_db() -> None:
+    """Initialize the database engine, run migrations, create tables, and seed data."""
+    global engine, SessionLocal, _db_path
+
+    _db_path = config.get_db_path()
+    _db_path.parent.mkdir(parents=True, exist_ok=True)
+
+    engine = create_engine(
+        f"sqlite:///{_db_path}",
+        connect_args={"check_same_thread": False},
+    )
+
+    SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+    run_migrations(engine)
+    Base.metadata.create_all(bind=engine)
+
+    # Create default audio channel if it doesn't exist
+    db = SessionLocal()
+    try:
+        default_channel = db.query(AudioChannel).filter(AudioChannel.is_default == True).first()
+        if not default_channel:
+            default_channel = AudioChannel(
+                id=str(uuid.uuid4()),
+                name="Default",
+                is_default=True,
+            )
+            db.add(default_channel)
+
+            for profile in db.query(VoiceProfile).all():
+                db.add(ProfileChannelMapping(
+                    profile_id=profile.id,
+                    channel_id=default_channel.id,
+                ))
+            db.commit()
+    finally:
+        db.close()
+
+    backfill_generation_versions(SessionLocal, Generation, GenerationVersion)
+    seed_builtin_presets(SessionLocal, EffectPreset)
+
+
+def get_db():
+    """Yield a database session (FastAPI dependency)."""
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()

backend/example_usage.py

@@ -1,221 +0,0 @@
-"""
-Example usage of the voicebox backend API.
-
-This script demonstrates how to:
-1. Create a voice profile
-2. Add samples to the profile
-3. Generate speech
-4. List history
-"""
-
-import requests
-import time
-from pathlib import Path
-
-# API base URL
-BASE_URL = "http://localhost:8000"
-
-
-def check_health():
-    """Check if the server is running."""
-    response = requests.get(f"{BASE_URL}/health")
-    data = response.json()
-    print(f"Server status: {data['status']}")
-    print(f"Model loaded: {data['model_loaded']}")
-    print(f"GPU available: {data['gpu_available']}")
-    print()
-    return data
-
-
-def create_profile(name: str, description: str = None, language: str = "en"):
-    """Create a new voice profile."""
-    response = requests.post(
-        f"{BASE_URL}/profiles",
-        json={
-            "name": name,
-            "description": description,
-            "language": language,
-        },
-    )
-    response.raise_for_status()
-    profile = response.json()
-    print(f"Created profile: {profile['name']} (ID: {profile['id']})")
-    return profile
-
-
-def add_sample(profile_id: str, audio_file: str, reference_text: str):
-    """Add a sample to a voice profile."""
-    with open(audio_file, "rb") as f:
-        files = {"file": f}
-        data = {"reference_text": reference_text}
-        response = requests.post(
-            f"{BASE_URL}/profiles/{profile_id}/samples",
-            files=files,
-            data=data,
-        )
-    response.raise_for_status()
-    sample = response.json()
-    print(f"Added sample: {sample['id']}")
-    return sample
-
-
-def generate_speech(profile_id: str, text: str, language: str = "en", seed: int = None):
-    """Generate speech using a voice profile."""
-    print(f"Generating speech: '{text[:50]}...'")
-    start_time = time.time()
-    
-    response = requests.post(
-        f"{BASE_URL}/generate",
-        json={
-            "profile_id": profile_id,
-            "text": text,
-            "language": language,
-            "seed": seed,
-        },
-    )
-    response.raise_for_status()
-    generation = response.json()
-    
-    elapsed = time.time() - start_time
-    print(f"Generated in {elapsed:.2f}s (duration: {generation['duration']:.2f}s)")
-    print(f"Generation ID: {generation['id']}")
-    return generation
-
-
-def download_audio(generation_id: str, output_file: str):
-    """Download generated audio."""
-    response = requests.get(f"{BASE_URL}/audio/{generation_id}")
-    response.raise_for_status()
-    
-    with open(output_file, "wb") as f:
-        f.write(response.content)
-    
-    print(f"Saved audio to: {output_file}")
-
-
-def list_profiles():
-    """List all voice profiles."""
-    response = requests.get(f"{BASE_URL}/profiles")
-    response.raise_for_status()
-    profiles = response.json()
-    
-    print(f"Found {len(profiles)} profiles:")
-    for profile in profiles:
-        print(f"  - {profile['name']} (ID: {profile['id']})")
-    
-    return profiles
-
-
-def list_history(profile_id: str = None, limit: int = 10):
-    """List generation history."""
-    params = {"limit": limit}
-    if profile_id:
-        params["profile_id"] = profile_id
-    
-    response = requests.get(f"{BASE_URL}/history", params=params)
-    response.raise_for_status()
-    history = response.json()
-    
-    print(f"Found {len(history)} generations:")
-    for gen in history:
-        print(f"  - {gen['text'][:50]}... ({gen['duration']:.2f}s)")
-    
-    return history
-
-
-def transcribe_audio(audio_file: str, language: str = None):
-    """Transcribe audio file."""
-    print(f"Transcribing: {audio_file}")
-    
-    with open(audio_file, "rb") as f:
-        files = {"file": f}
-        data = {}
-        if language:
-            data["language"] = language
-        
-        response = requests.post(
-            f"{BASE_URL}/transcribe",
-            files=files,
-            data=data,
-        )
-    
-    response.raise_for_status()
-    result = response.json()
-    
-    print(f"Transcription: {result['text']}")
-    print(f"Duration: {result['duration']:.2f}s")
-    return result
-
-
-def main():
-    """Run example workflow."""
-    print("=" * 60)
-    print("voicebox Backend API Example")
-    print("=" * 60)
-    print()
-    
-    # 1. Check health
-    print("1. Checking server health...")
-    check_health()
-    
-    # 2. Create a profile
-    print("2. Creating voice profile...")
-    profile = create_profile(
-        name="Example Voice",
-        description="A test voice profile",
-        language="en",
-    )
-    profile_id = profile["id"]
-    print()
-    
-    # 3. Add samples (you'll need actual audio files)
-    print("3. Adding samples...")
-    print("   (Skipping - add your own audio files here)")
-    # Uncomment and add your audio file:
-    # sample = add_sample(
-    #     profile_id,
-    #     "path/to/your/sample.wav",
-    #     "This is the transcript of the audio",
-    # )
-    print()
-    
-    # 4. Generate speech (requires samples to be added first)
-    print("4. Generating speech...")
-    print("   (Skipping - add samples first)")
-    # Uncomment after adding samples:
-    # generation = generate_speech(
-    #     profile_id,
-    #     "Hello, this is a test of the voice cloning system.",
-    #     language="en",
-    #     seed=42,
-    # )
-    # 
-    # # 5. Download audio
-    # print("\n5. Downloading audio...")
-    # download_audio(generation["id"], "output.wav")
-    print()
-    
-    # 6. List profiles
-    print("6. Listing all profiles...")
-    list_profiles()
-    print()
-    
-    # 7. List history
-    print("7. Listing generation history...")
-    list_history(limit=5)
-    print()
-    
-    # 8. Transcribe audio (you'll need an audio file)
-    print("8. Transcribing audio...")
-    print("   (Skipping - add your own audio file here)")
-    # Uncomment and add your audio file:
-    # transcribe_audio("path/to/audio.wav", language="en")
-    print()
-    
-    print("=" * 60)
-    print("Example complete!")
-    print("=" * 60)
-
-
-if __name__ == "__main__":
-    main()

backend/migrate_add_instruct.py

@@ -1,48 +0,0 @@
-"""
-Database migration script to add instruct column to generations table.
-
-Run this once to update existing databases:
-    python -m backend.migrate_add_instruct
-"""
-
-import sqlite3
-import os
-from pathlib import Path
-
-
-def migrate():
-    """Add instruct column to generations table if it doesn't exist."""
-    # Get data directory
-    data_dir = os.environ.get("VOICEBOX_DATA_DIR")
-    if data_dir:
-        db_path = Path(data_dir) / "voicebox.db"
-    else:
-        db_path = Path.cwd() / "data" / "voicebox.db"
-
-    if not db_path.exists():
-        print(f"Database not found at {db_path}, skipping migration")
-        return
-
-    conn = sqlite3.connect(db_path)
-    cursor = conn.cursor()
-
-    # Check if instruct column already exists
-    cursor.execute("PRAGMA table_info(generations)")
-    columns = [row[1] for row in cursor.fetchall()]
-
-    if 'instruct' in columns:
-        print("instruct column already exists, skipping migration")
-        conn.close()
-        return
-
-    # Add instruct column
-    print("Adding instruct column to generations table...")
-    cursor.execute("ALTER TABLE generations ADD COLUMN instruct TEXT")
-    conn.commit()
-    conn.close()
-
-    print("Migration complete!")
-
-
-if __name__ == "__main__":
-    migrate()

backend/models.py

@@ -9,13 +9,17 @@ from datetime import datetime
 
 class VoiceProfileCreate(BaseModel):
     """Request model for creating a voice profile."""
+
     name: str = Field(..., min_length=1, max_length=100)
     description: Optional[str] = Field(None, max_length=500)
-    language: str = Field(default="en", pattern="^(zh|en|ja|ko|de|fr|ru|pt|es|it|he|ar|da|el|fi|hi|ms|nl|no|pl|sv|sw|tr)$")
+    language: str = Field(
+        default="en", pattern="^(zh|en|ja|ko|de|fr|ru|pt|es|it|he|ar|da|el|fi|hi|ms|nl|no|pl|sv|sw|tr)$"
+    )
 
 
 class VoiceProfileResponse(BaseModel):
     """Response model for voice profile."""
+
     id: str
     name: str
     description: Optional[str]
@@ -33,16 +37,19 @@ class VoiceProfileResponse(BaseModel):
 
 class ProfileSampleCreate(BaseModel):
     """Request model for adding a sample to a profile."""
+
     reference_text: str = Field(..., min_length=1, max_length=1000)
 
 
 class ProfileSampleUpdate(BaseModel):
     """Request model for updating a profile sample."""
+
     reference_text: str = Field(..., min_length=1, max_length=1000)
 
 
 class ProfileSampleResponse(BaseModel):
     """Response model for profile sample."""
+
     id: str
     profile_id: str
     audio_path: str
@@ -54,21 +61,29 @@ class ProfileSampleResponse(BaseModel):
 
 class GenerationRequest(BaseModel):
     """Request model for voice generation."""
+
     profile_id: str
     text: str = Field(..., min_length=1, max_length=50000)
-    language: str = Field(default="en", pattern="^(zh|en|ja|ko|de|fr|ru|pt|es|it|he)$")
+    language: str = Field(default="en", pattern="^(zh|en|ja|ko|de|fr|ru|pt|es|it|he|ar|da|el|fi|hi|ms|nl|no|pl|sv|sw|tr)$")
     seed: Optional[int] = Field(None, ge=0)
     model_size: Optional[str] = Field(default="1.7B", pattern="^(1\\.7B|0\\.6B)$")
     instruct: Optional[str] = Field(None, max_length=500)
     engine: Optional[str] = Field(default="qwen", pattern="^(qwen|luxtts|chatterbox|chatterbox_turbo)$")
-    max_chunk_chars: int = Field(default=800, ge=100, le=5000, description="Max characters per chunk for long text splitting")
+    max_chunk_chars: int = Field(
-    crossfade_ms: int = Field(default=50, ge=0, le=500, description="Crossfade duration in ms between chunks (0 for hard cut)")
+        default=800, ge=100, le=5000, description="Max characters per chunk for long text splitting"
+    )
+    crossfade_ms: int = Field(
+        default=50, ge=0, le=500, description="Crossfade duration in ms between chunks (0 for hard cut)"
+    )
     normalize: bool = Field(default=True, description="Normalize output audio volume")
-    effects_chain: Optional[List["EffectConfig"]] = Field(None, description="Effects chain to apply after generation (overrides profile default)")
+    effects_chain: Optional[List["EffectConfig"]] = Field(
+        None, description="Effects chain to apply after generation (overrides profile default)"
+    )
 
 
 class GenerationResponse(BaseModel):
     """Response model for voice generation."""
+
     id: str
     profile_id: str
     text: str
@@ -92,6 +107,7 @@ class GenerationResponse(BaseModel):
 
 class HistoryQuery(BaseModel):
     """Query model for generation history."""
+
     profile_id: Optional[str] = None
     search: Optional[str] = None
     limit: int = Field(default=50, ge=1, le=100)
@@ -100,6 +116,7 @@ class HistoryQuery(BaseModel):
 
 class HistoryResponse(BaseModel):
     """Response model for history entry (includes profile name)."""
+
     id: str
     profile_id: str
     profile_name: str
@@ -124,23 +141,28 @@ class HistoryResponse(BaseModel):
 
 class HistoryListResponse(BaseModel):
     """Response model for history list."""
+
     items: List[HistoryResponse]
     total: int
 
 
 class TranscriptionRequest(BaseModel):
     """Request model for audio transcription."""
-    language: Optional[str] = Field(None, pattern="^(en|zh)$")
+
+    language: Optional[str] = Field(None, pattern="^(en|zh|ja|ko|de|fr|ru|pt|es|it)$")
+    model: Optional[str] = Field(None, pattern="^(base|small|medium|large|turbo)$")
 
 
 class TranscriptionResponse(BaseModel):
     """Response model for transcription."""
+
     text: str
     duration: float
 
 
 class HealthResponse(BaseModel):
     """Response model for health check."""
+
     status: str
     model_loaded: bool
     model_downloaded: Optional[bool] = None  # Whether model is cached/downloaded
@@ -154,6 +176,7 @@ class HealthResponse(BaseModel):
 
 class DirectoryCheck(BaseModel):
     """Health status for a single directory."""
+
     path: str
     exists: bool
     writable: bool
@@ -162,6 +185,7 @@ class DirectoryCheck(BaseModel):
 
 class FilesystemHealthResponse(BaseModel):
     """Response model for filesystem health check."""
+
     healthy: bool
     disk_free_mb: Optional[float] = None
     disk_total_mb: Optional[float] = None
@@ -170,6 +194,7 @@ class FilesystemHealthResponse(BaseModel):
 
 class ModelStatus(BaseModel):
     """Response model for model status."""
+
     model_name: str
     display_name: str
     hf_repo_id: Optional[str] = None  # HuggingFace repository ID
@@ -181,33 +206,38 @@ class ModelStatus(BaseModel):
 
 class ModelStatusListResponse(BaseModel):
     """Response model for model status list."""
+
     models: List[ModelStatus]
 
 
 class ModelDownloadRequest(BaseModel):
     """Request model for triggering model download."""
+
     model_name: str
 
 
 class ModelMigrateRequest(BaseModel):
     """Request model for migrating models to a new directory."""
+
     destination: str
 
 
 class ActiveDownloadTask(BaseModel):
     """Response model for active download task."""
+
     model_name: str
     status: str
     started_at: datetime
     error: Optional[str] = None
     progress: Optional[float] = None  # 0-100 percentage
-    current: Optional[int] = None     # bytes downloaded
+    current: Optional[int] = None  # bytes downloaded
-    total: Optional[int] = None       # total bytes
+    total: Optional[int] = None  # total bytes
-    filename: Optional[str] = None    # current file being downloaded
+    filename: Optional[str] = None  # current file being downloaded
 
 
 class ActiveGenerationTask(BaseModel):
     """Response model for active generation task."""
+
     task_id: str
     profile_id: str
     text_preview: str
@@ -216,24 +246,28 @@ class ActiveGenerationTask(BaseModel):
 
 class ActiveTasksResponse(BaseModel):
     """Response model for active tasks."""
+
     downloads: List[ActiveDownloadTask]
     generations: List[ActiveGenerationTask]
 
 
 class AudioChannelCreate(BaseModel):
     """Request model for creating an audio channel."""
+
     name: str = Field(..., min_length=1, max_length=100)
     device_ids: List[str] = Field(default_factory=list)
 
 
 class AudioChannelUpdate(BaseModel):
     """Request model for updating an audio channel."""
+
     name: Optional[str] = Field(None, min_length=1, max_length=100)
     device_ids: Optional[List[str]] = None
 
 
 class AudioChannelResponse(BaseModel):
     """Response model for audio channel."""
+
     id: str
     name: str
     is_default: bool
@@ -246,22 +280,26 @@ class AudioChannelResponse(BaseModel):
 
 class ChannelVoiceAssignment(BaseModel):
     """Request model for assigning voices to a channel."""
+
     profile_ids: List[str]
 
 
 class ProfileChannelAssignment(BaseModel):
     """Request model for assigning channels to a profile."""
+
     channel_ids: List[str]
 
 
 class StoryCreate(BaseModel):
     """Request model for creating a story."""
+
     name: str = Field(..., min_length=1, max_length=100)
     description: Optional[str] = Field(None, max_length=500)
 
 
 class StoryResponse(BaseModel):
     """Response model for story (list view)."""
+
     id: str
     name: str
     description: Optional[str]
@@ -275,6 +313,7 @@ class StoryResponse(BaseModel):
 
 class StoryItemDetail(BaseModel):
     """Detail model for story item with generation info."""
+
     id: str
     story_id: str
     generation_id: str
@@ -304,6 +343,7 @@ class StoryItemDetail(BaseModel):
 
 class StoryDetailResponse(BaseModel):
     """Response model for story with items."""
+
     id: str
     name: str
     description: Optional[str]
@@ -317,6 +357,7 @@ class StoryDetailResponse(BaseModel):
 
 class StoryItemCreate(BaseModel):
     """Request model for adding a generation to a story."""
+
     generation_id: str
     start_time_ms: Optional[int] = None  # If not provided, will be calculated automatically
     track: Optional[int] = 0  # Track number (0 = main track)
@@ -324,48 +365,52 @@ class StoryItemCreate(BaseModel):
 
 class StoryItemUpdateTime(BaseModel):
     """Request model for updating a story item's timecode."""
+
     generation_id: str
     start_time_ms: int = Field(..., ge=0)
 
 
 class StoryItemBatchUpdate(BaseModel):
     """Request model for batch updating story item timecodes."""
+
     updates: List[StoryItemUpdateTime]
 
 
 class StoryItemReorder(BaseModel):
     """Request model for reordering story items."""
+
     generation_ids: List[str] = Field(..., min_length=1)
 
 
 class StoryItemMove(BaseModel):
     """Request model for moving a story item (position and/or track)."""
+
     start_time_ms: int = Field(..., ge=0)
     track: int = 0
 
 
 class StoryItemTrim(BaseModel):
     """Request model for trimming a story item."""
+
     trim_start_ms: int = Field(..., ge=0)
     trim_end_ms: int = Field(..., ge=0)
 
 
 class StoryItemSplit(BaseModel):
     """Request model for splitting a story item."""
+
     split_time_ms: int = Field(..., ge=0)  # Time within the clip to split at (relative to clip start)
 
 
 class StoryItemVersionUpdate(BaseModel):
     """Request model for setting a story item's pinned version."""
+
     version_id: Optional[str] = None  # null = use generation default
 
 
-# ============================================
-# Effects & Versions
-# ============================================
-
 class EffectConfig(BaseModel):
     """A single effect in an effects chain."""
+
     type: str
     enabled: bool = True
     params: dict = Field(default_factory=dict)
@@ -373,11 +418,13 @@ class EffectConfig(BaseModel):
 
 class EffectsChain(BaseModel):
     """An ordered list of effects to apply."""
+
     effects: List[EffectConfig] = Field(default_factory=list)
 
 
 class EffectPresetCreate(BaseModel):
     """Request model for creating an effect preset."""
+
     name: str = Field(..., min_length=1, max_length=100)
     description: Optional[str] = Field(None, max_length=500)
     effects_chain: List[EffectConfig]
@@ -385,6 +432,7 @@ class EffectPresetCreate(BaseModel):
 
 class EffectPresetUpdate(BaseModel):
     """Request model for updating an effect preset."""
+
     name: Optional[str] = Field(None, min_length=1, max_length=100)
     description: Optional[str] = None
     effects_chain: Optional[List[EffectConfig]] = None
@@ -392,6 +440,7 @@ class EffectPresetUpdate(BaseModel):
 
 class EffectPresetResponse(BaseModel):
     """Response model for effect preset."""
+
     id: str
     name: str
     description: Optional[str] = None
@@ -405,6 +454,7 @@ class EffectPresetResponse(BaseModel):
 
 class GenerationVersionResponse(BaseModel):
     """Response model for a generation version."""
+
     id: str
     generation_id: str
     label: str
@@ -420,19 +470,24 @@ class GenerationVersionResponse(BaseModel):
 
 class ApplyEffectsRequest(BaseModel):
     """Request to apply effects to an existing generation."""
+
     effects_chain: List[EffectConfig]
-    source_version_id: Optional[str] = Field(None, description="Version to use as source audio (defaults to clean/original)")
+    source_version_id: Optional[str] = Field(
+        None, description="Version to use as source audio (defaults to clean/original)"
+    )
     label: Optional[str] = Field(None, max_length=100, description="Label for this version (auto-generated if omitted)")
     set_as_default: bool = Field(default=True, description="Set this version as the default")
 
 
 class ProfileEffectsUpdate(BaseModel):
     """Request to update the default effects chain on a profile."""
+
     effects_chain: Optional[List[EffectConfig]] = Field(None, description="Effects chain (null to remove)")
 
 
 class AvailableEffectParam(BaseModel):
     """Description of a single effect parameter."""
+
     default: float
     min: float
     max: float
@@ -442,6 +497,7 @@ class AvailableEffectParam(BaseModel):
 
 class AvailableEffect(BaseModel):
     """Description of an available effect type."""
+
     type: str
     label: str
     description: str
@@ -450,4 +506,5 @@ class AvailableEffect(BaseModel):
 
 class AvailableEffectsResponse(BaseModel):
     """Response listing all available effect types."""
+
     effects: List[AvailableEffect]

backend/pyproject.toml

@@ -0,0 +1,83 @@
+[project]
+name = "voicebox-backend"
+version = "0.2.3"
+requires-python = ">=3.12"
+
+# ---------------------------------------------------------------------------
+# Ruff – linter + formatter
+# ---------------------------------------------------------------------------
+
+[tool.ruff]
+target-version = "py312"
+line-length = 120
+src = ["."]
+
+# Files/dirs to skip entirely.
+extend-exclude = [
+    "voicebox-server.spec",
+    "build_binary.py",
+]
+
+[tool.ruff.lint]
+select = [
+    "F",     # pyflakes
+    "E",     # pycodestyle errors
+    "W",     # pycodestyle warnings
+    "I",     # isort
+    "N",     # pep8-naming
+    "UP",    # pyupgrade (modernize syntax for 3.12)
+    "B",     # flake8-bugbear
+    "A",     # flake8-builtins (shadowing built-in names)
+    "SIM",   # flake8-simplify
+    "T20",   # flake8-print (flag print() calls)
+    "RET",   # flake8-return
+    "PIE",   # misc lints
+    "PT",    # flake8-pytest-style
+    "RUF",   # ruff-specific rules
+    "ERA",   # commented-out code detection
+    "FIX",   # flag TODO/FIXME/HACK/XXX for review
+]
+
+ignore = [
+    # Allow print() in existing code -- remove items from this list as files
+    # are migrated to logging during the refactor.
+    "T201",   # print() found
+
+    # These conflict with the formatter or are too noisy during migration:
+    "E501",   # line too long (formatter handles this)
+    "RET504", # unnecessary assignment before return
+    "SIM108", # use ternary operator (sometimes less readable)
+    "B008",   # function call in default argument (FastAPI Depends() pattern)
+    "UP007",  # use X | Y for union (auto-fixed by UP, but noisy on big diffs)
+]
+
+# Per-file rule overrides.
+[tool.ruff.lint.per-file-ignores]
+# Tests can use assert, print, and magic values freely.
+"tests/**" = ["S101", "T201", "PLR2004", "ERA001"]
+# __init__.py re-exports are expected to have unused imports.
+"**/__init__.py" = ["F401"]
+# Entry points and scripts legitimately use print.
+"server.py" = ["T201"]
+"main.py" = ["T201"]
+# AMD GPU env vars must be set before torch import.
+"app.py" = ["E402"]
+
+[tool.ruff.lint.isort]
+known-first-party = ["backend"]
+# Group "from backend.*" imports into the first-party section.
+force-single-line = false
+combine-as-imports = true
+
+[tool.ruff.format]
+quote-style = "double"
+indent-style = "space"
+docstring-code-format = true
+
+# ---------------------------------------------------------------------------
+# pytest
+# ---------------------------------------------------------------------------
+
+[tool.pytest.ini_options]
+testpaths = ["tests"]
+asyncio_mode = "auto"

backend/routes/__init__.py

@@ -0,0 +1,32 @@
+"""Route registration for the voicebox API."""
+
+from fastapi import FastAPI
+
+
+def register_routers(app: FastAPI) -> None:
+    """Include all domain routers on the application."""
+    from .health import router as health_router
+    from .profiles import router as profiles_router
+    from .channels import router as channels_router
+    from .generations import router as generations_router
+    from .history import router as history_router
+    from .transcription import router as transcription_router
+    from .stories import router as stories_router
+    from .effects import router as effects_router
+    from .audio import router as audio_router
+    from .models import router as models_router
+    from .tasks import router as tasks_router
+    from .cuda import router as cuda_router
+
+    app.include_router(health_router)
+    app.include_router(profiles_router)
+    app.include_router(channels_router)
+    app.include_router(generations_router)
+    app.include_router(history_router)
+    app.include_router(transcription_router)
+    app.include_router(stories_router)
+    app.include_router(effects_router)
+    app.include_router(audio_router)
+    app.include_router(models_router)
+    app.include_router(tasks_router)
+    app.include_router(cuda_router)

backend/routes/audio.py

@@ -0,0 +1,71 @@
+"""Audio file serving endpoints."""
+
+from pathlib import Path
+
+from fastapi import APIRouter, Depends, HTTPException
+from fastapi.responses import FileResponse
+from sqlalchemy.orm import Session
+
+from .. import models
+from ..services import history
+from ..database import get_db
+
+router = APIRouter()
+
+
+@router.get("/audio/version/{version_id}")
+async def get_version_audio(version_id: str, db: Session = Depends(get_db)):
+    """Serve audio for a specific version."""
+    from ..services import versions as versions_mod
+
+    version = versions_mod.get_version(version_id, db)
+    if not version:
+        raise HTTPException(status_code=404, detail="Version not found")
+
+    audio_path = Path(version.audio_path)
+    if not audio_path.exists():
+        raise HTTPException(status_code=404, detail="Audio file not found")
+
+    return FileResponse(
+        audio_path,
+        media_type="audio/wav",
+        filename=f"generation_{version.generation_id}_{version.label}.wav",
+    )
+
+
+@router.get("/audio/{generation_id}")
+async def get_audio(generation_id: str, db: Session = Depends(get_db)):
+    """Serve generated audio file (serves the default version)."""
+    generation = await history.get_generation(generation_id, db)
+    if not generation:
+        raise HTTPException(status_code=404, detail="Generation not found")
+
+    audio_path = Path(generation.audio_path)
+    if not audio_path.exists():
+        raise HTTPException(status_code=404, detail="Audio file not found")
+
+    return FileResponse(
+        audio_path,
+        media_type="audio/wav",
+        filename=f"generation_{generation_id}.wav",
+    )
+
+
+@router.get("/samples/{sample_id}")
+async def get_sample_audio(sample_id: str, db: Session = Depends(get_db)):
+    """Serve profile sample audio file."""
+    from ..database import ProfileSample as DBProfileSample
+
+    sample = db.query(DBProfileSample).filter_by(id=sample_id).first()
+    if not sample:
+        raise HTTPException(status_code=404, detail="Sample not found")
+
+    audio_path = Path(sample.audio_path)
+    if not audio_path.exists():
+        raise HTTPException(status_code=404, detail="Audio file not found")
+
+    return FileResponse(
+        audio_path,
+        media_type="audio/wav",
+        filename=f"sample_{sample_id}.wav",
+    )

backend/routes/channels.py

@@ -0,0 +1,98 @@
+"""Audio channel endpoints."""
+
+from fastapi import APIRouter, Depends, HTTPException
+from sqlalchemy.orm import Session
+
+from .. import models
+from ..services import channels
+from ..database import get_db
+
+router = APIRouter()
+
+
+@router.get("/channels", response_model=list[models.AudioChannelResponse])
+async def list_channels(db: Session = Depends(get_db)):
+    """List all audio channels."""
+    return await channels.list_channels(db)
+
+
+@router.post("/channels", response_model=models.AudioChannelResponse)
+async def create_channel(
+    data: models.AudioChannelCreate,
+    db: Session = Depends(get_db),
+):
+    """Create a new audio channel."""
+    try:
+        return await channels.create_channel(data, db)
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.get("/channels/{channel_id}", response_model=models.AudioChannelResponse)
+async def get_channel(
+    channel_id: str,
+    db: Session = Depends(get_db),
+):
+    """Get an audio channel by ID."""
+    channel = await channels.get_channel(channel_id, db)
+    if not channel:
+        raise HTTPException(status_code=404, detail="Channel not found")
+    return channel
+
+
+@router.put("/channels/{channel_id}", response_model=models.AudioChannelResponse)
+async def update_channel(
+    channel_id: str,
+    data: models.AudioChannelUpdate,
+    db: Session = Depends(get_db),
+):
+    """Update an audio channel."""
+    try:
+        channel = await channels.update_channel(channel_id, data, db)
+        if not channel:
+            raise HTTPException(status_code=404, detail="Channel not found")
+        return channel
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.delete("/channels/{channel_id}")
+async def delete_channel(
+    channel_id: str,
+    db: Session = Depends(get_db),
+):
+    """Delete an audio channel."""
+    try:
+        success = await channels.delete_channel(channel_id, db)
+        if not success:
+            raise HTTPException(status_code=404, detail="Channel not found")
+        return {"message": "Channel deleted successfully"}
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.get("/channels/{channel_id}/voices")
+async def get_channel_voices(
+    channel_id: str,
+    db: Session = Depends(get_db),
+):
+    """Get list of profile IDs assigned to a channel."""
+    try:
+        profile_ids = await channels.get_channel_voices(channel_id, db)
+        return {"profile_ids": profile_ids}
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.put("/channels/{channel_id}/voices")
+async def set_channel_voices(
+    channel_id: str,
+    data: models.ChannelVoiceAssignment,
+    db: Session = Depends(get_db),
+):
+    """Set which voices are assigned to a channel."""
+    try:
+        await channels.set_channel_voices(channel_id, data, db)
+        return {"message": "Channel voices updated successfully"}
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))

backend/routes/cuda.py

@@ -0,0 +1,82 @@
+"""CUDA backend management endpoints."""
+
+import logging
+
+from fastapi import APIRouter, HTTPException
+from fastapi.responses import StreamingResponse
+
+from ..services.task_queue import create_background_task
+from ..utils.progress import get_progress_manager
+
+router = APIRouter()
+
+logger = logging.getLogger(__name__)
+
+
+@router.get("/backend/cuda-status")
+async def get_cuda_status():
+    """Get CUDA backend download/availability status."""
+    from ..services import cuda
+
+    return cuda.get_cuda_status()
+
+
+@router.post("/backend/download-cuda")
+async def download_cuda_backend():
+    """Download the CUDA backend binary."""
+    from ..services import cuda
+
+    if cuda.get_cuda_binary_path() is not None:
+        raise HTTPException(status_code=409, detail="CUDA backend already downloaded")
+
+    progress_manager = get_progress_manager()
+    existing = progress_manager.get_progress(cuda.PROGRESS_KEY)
+    if existing and existing.get("status") == "downloading":
+        raise HTTPException(status_code=409, detail="CUDA backend download already in progress")
+
+    async def _download():
+        try:
+            await cuda.download_cuda_binary()
+        except Exception as e:
+            logger.error("CUDA download failed: %s", e)
+
+    create_background_task(_download())
+    return {"message": "CUDA backend download started", "progress_key": "cuda-backend"}
+
+
+@router.delete("/backend/cuda")
+async def delete_cuda_backend():
+    """Delete the downloaded CUDA backend binary."""
+    from ..services import cuda
+
+    if cuda.is_cuda_active():
+        raise HTTPException(
+            status_code=409,
+            detail="Cannot delete CUDA backend while it is active. Switch to CPU first.",
+        )
+
+    deleted = await cuda.delete_cuda_binary()
+    if not deleted:
+        raise HTTPException(status_code=404, detail="No CUDA backend found to delete")
+
+    return {"message": "CUDA backend deleted"}
+
+
+@router.get("/backend/cuda-progress")
+async def get_cuda_download_progress():
+    """Get CUDA backend download progress via Server-Sent Events."""
+    progress_manager = get_progress_manager()
+
+    async def event_generator():
+        async for event in progress_manager.subscribe("cuda-backend"):
+            yield event
+
+    return StreamingResponse(
+        event_generator(),
+        media_type="text/event-stream",
+        headers={
+            "Cache-Control": "no-cache",
+            "Connection": "keep-alive",
+            "X-Accel-Buffering": "no",
+        },
+    )

backend/routes/effects.py

@@ -0,0 +1,261 @@
+"""Effects presets and generation version endpoints."""
+
+import asyncio
+import io
+import uuid
+from pathlib import Path
+
+from fastapi import APIRouter, Depends, HTTPException
+from fastapi.responses import StreamingResponse
+from sqlalchemy.orm import Session
+
+from .. import config, models
+from ..services import history
+from ..database import Generation as DBGeneration, get_db
+
+router = APIRouter()
+
+
+@router.post("/effects/preview/{generation_id}")
+async def preview_effects(
+    generation_id: str,
+    data: models.ApplyEffectsRequest,
+    db: Session = Depends(get_db),
+):
+    """Apply effects to a generation's clean audio and stream back without saving."""
+    gen = db.query(DBGeneration).filter_by(id=generation_id).first()
+    if not gen:
+        raise HTTPException(status_code=404, detail="Generation not found")
+    if (gen.status or "completed") != "completed":
+        raise HTTPException(status_code=400, detail="Generation is not completed")
+
+    from ..services import versions as versions_mod
+    from ..utils.effects import apply_effects, validate_effects_chain
+    from ..utils.audio import load_audio
+
+    chain_dicts = [e.model_dump() for e in data.effects_chain]
+    error = validate_effects_chain(chain_dicts)
+    if error:
+        raise HTTPException(status_code=400, detail=error)
+
+    all_versions = versions_mod.list_versions(generation_id, db)
+    clean_version = next((v for v in all_versions if v.effects_chain is None), None)
+    source_path = clean_version.audio_path if clean_version else gen.audio_path
+    if not source_path or not Path(source_path).exists():
+        raise HTTPException(status_code=404, detail="Source audio file not found")
+
+    audio, sample_rate = await asyncio.to_thread(load_audio, source_path)
+    processed = await asyncio.to_thread(apply_effects, audio, sample_rate, chain_dicts)
+
+    import soundfile as sf
+
+    buf = io.BytesIO()
+    await asyncio.to_thread(lambda: sf.write(buf, processed, sample_rate, format="WAV"))
+    buf.seek(0)
+
+    return StreamingResponse(
+        buf,
+        media_type="audio/wav",
+        headers={
+            "Content-Disposition": f'inline; filename="preview_{generation_id}.wav"',
+            "Cache-Control": "no-cache, no-store",
+        },
+    )
+
+
+@router.get("/effects/available", response_model=models.AvailableEffectsResponse)
+async def get_available_effects():
+    """List all available effect types with parameter definitions."""
+    from ..utils.effects import get_available_effects as _get_effects
+
+    return models.AvailableEffectsResponse(effects=[models.AvailableEffect(**e) for e in _get_effects()])
+
+
+@router.get("/effects/presets", response_model=list[models.EffectPresetResponse])
+async def list_effect_presets(db: Session = Depends(get_db)):
+    """List all effect presets (built-in + user-created)."""
+    from ..services import effects as effects_mod
+
+    return effects_mod.list_presets(db)
+
+
+@router.get("/effects/presets/{preset_id}", response_model=models.EffectPresetResponse)
+async def get_effect_preset(preset_id: str, db: Session = Depends(get_db)):
+    """Get a specific effect preset."""
+    from ..services import effects as effects_mod
+
+    preset = effects_mod.get_preset(preset_id, db)
+    if not preset:
+        raise HTTPException(status_code=404, detail="Preset not found")
+    return preset
+
+
+@router.post("/effects/presets", response_model=models.EffectPresetResponse)
+async def create_effect_preset(
+    data: models.EffectPresetCreate,
+    db: Session = Depends(get_db),
+):
+    """Create a new effect preset."""
+    from ..services import effects as effects_mod
+
+    try:
+        return effects_mod.create_preset(data, db)
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.put("/effects/presets/{preset_id}", response_model=models.EffectPresetResponse)
+async def update_effect_preset(
+    preset_id: str,
+    data: models.EffectPresetUpdate,
+    db: Session = Depends(get_db),
+):
+    """Update an effect preset."""
+    from ..services import effects as effects_mod
+
+    try:
+        result = effects_mod.update_preset(preset_id, data, db)
+        if not result:
+            raise HTTPException(status_code=404, detail="Preset not found")
+        return result
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.delete("/effects/presets/{preset_id}")
+async def delete_effect_preset(preset_id: str, db: Session = Depends(get_db)):
+    """Delete a user effect preset."""
+    from ..services import effects as effects_mod
+
+    try:
+        if not effects_mod.delete_preset(preset_id, db):
+            raise HTTPException(status_code=404, detail="Preset not found")
+        return {"status": "deleted"}
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.get(
+    "/generations/{generation_id}/versions",
+    response_model=list[models.GenerationVersionResponse],
+)
+async def list_generation_versions(
+    generation_id: str,
+    db: Session = Depends(get_db),
+):
+    """List all versions for a generation."""
+    gen = await history.get_generation(generation_id, db)
+    if not gen:
+        raise HTTPException(status_code=404, detail="Generation not found")
+
+    from ..services import versions as versions_mod
+
+    return versions_mod.list_versions(generation_id, db)
+
+
+@router.post(
+    "/generations/{generation_id}/versions/apply-effects",
+    response_model=models.GenerationVersionResponse,
+)
+async def apply_effects_to_generation(
+    generation_id: str,
+    data: models.ApplyEffectsRequest,
+    db: Session = Depends(get_db),
+):
+    """Apply an effects chain to an existing generation, creating a new version."""
+    gen = db.query(DBGeneration).filter_by(id=generation_id).first()
+    if not gen:
+        raise HTTPException(status_code=404, detail="Generation not found")
+    if (gen.status or "completed") != "completed":
+        raise HTTPException(status_code=400, detail="Generation is not completed")
+
+    from ..services import versions as versions_mod
+    from ..utils.effects import apply_effects, validate_effects_chain
+    from ..utils.audio import load_audio, save_audio
+
+    chain_dicts = [e.model_dump() for e in data.effects_chain]
+    error = validate_effects_chain(chain_dicts)
+    if error:
+        raise HTTPException(status_code=400, detail=error)
+
+    all_versions = versions_mod.list_versions(generation_id, db)
+    source_version_id = data.source_version_id
+    if source_version_id:
+        source_version = next((v for v in all_versions if v.id == source_version_id), None)
+        if not source_version:
+            raise HTTPException(status_code=404, detail="Source version not found")
+        source_path = source_version.audio_path
+    else:
+        clean_version = next((v for v in all_versions if v.effects_chain is None), None)
+        if not clean_version:
+            source_path = gen.audio_path
+        else:
+            source_path = clean_version.audio_path
+            source_version_id = clean_version.id
+
+    if not source_path or not Path(source_path).exists():
+        raise HTTPException(status_code=404, detail="Source audio file not found")
+
+    audio, sample_rate = await asyncio.to_thread(load_audio, source_path)
+    processed_audio = await asyncio.to_thread(apply_effects, audio, sample_rate, chain_dicts)
+
+    version_id = str(uuid.uuid4())
+    processed_path = config.get_generations_dir() / f"{generation_id}_{version_id[:8]}.wav"
+    await asyncio.to_thread(save_audio, processed_audio, str(processed_path), sample_rate)
+
+    label = data.label or f"version-{len(all_versions) + 1}"
+
+    version = versions_mod.create_version(
+        generation_id=generation_id,
+        label=label,
+        audio_path=str(processed_path),
+        db=db,
+        effects_chain=chain_dicts,
+        is_default=data.set_as_default,
+        source_version_id=source_version_id,
+    )
+
+    return version
+
+
+@router.put(
+    "/generations/{generation_id}/versions/{version_id}/set-default",
+    response_model=models.GenerationVersionResponse,
+)
+async def set_default_version(
+    generation_id: str,
+    version_id: str,
+    db: Session = Depends(get_db),
+):
+    """Set a specific version as the default for a generation."""
+    from ..services import versions as versions_mod
+
+    version = versions_mod.get_version(version_id, db)
+    if not version or version.generation_id != generation_id:
+        raise HTTPException(status_code=404, detail="Version not found")
+
+    result = versions_mod.set_default_version(version_id, db)
+    if not result:
+        raise HTTPException(status_code=404, detail="Version not found")
+    return result
+
+
+@router.delete("/generations/{generation_id}/versions/{version_id}")
+async def delete_generation_version(
+    generation_id: str,
+    version_id: str,
+    db: Session = Depends(get_db),
+):
+    """Delete a version. Cannot delete the last remaining version."""
+    from ..services import versions as versions_mod
+
+    version = versions_mod.get_version(version_id, db)
+    if not version or version.generation_id != generation_id:
+        raise HTTPException(status_code=404, detail="Version not found")
+
+    if not versions_mod.delete_version(version_id, db):
+        raise HTTPException(
+            status_code=400,
+            detail="Cannot delete the last remaining version",
+        )
+    return {"status": "deleted"}

backend/routes/generations.py

@@ -0,0 +1,285 @@
+"""TTS generation endpoints."""
+
+import asyncio
+import logging
+import uuid
+
+from fastapi import APIRouter, Depends, HTTPException
+from fastapi.responses import StreamingResponse
+from sqlalchemy.orm import Session
+
+logger = logging.getLogger(__name__)
+
+from .. import models
+from ..services import history, profiles, tts
+from ..database import Generation as DBGeneration, VoiceProfile as DBVoiceProfile, get_db
+from ..services.generation import run_generation
+from ..services.task_queue import enqueue_generation
+from ..utils.tasks import get_task_manager
+
+router = APIRouter()
+
+
+@router.post("/generate", response_model=models.GenerationResponse)
+async def generate_speech(
+    data: models.GenerationRequest,
+    db: Session = Depends(get_db),
+):
+    """Generate speech from text using a voice profile."""
+    task_manager = get_task_manager()
+    generation_id = str(uuid.uuid4())
+
+    profile = await profiles.get_profile(data.profile_id, db)
+    if not profile:
+        raise HTTPException(status_code=404, detail="Profile not found")
+
+    from ..backends import engine_has_model_sizes
+
+    engine = data.engine or "qwen"
+    model_size = (data.model_size or "1.7B") if engine_has_model_sizes(engine) else None
+
+    generation = await history.create_generation(
+        profile_id=data.profile_id,
+        text=data.text,
+        language=data.language,
+        audio_path="",
+        duration=0,
+        seed=data.seed,
+        db=db,
+        instruct=data.instruct,
+        generation_id=generation_id,
+        status="generating",
+        engine=engine,
+        model_size=model_size if engine_has_model_sizes(engine) else None,
+    )
+
+    task_manager.start_generation(
+        task_id=generation_id,
+        profile_id=data.profile_id,
+        text=data.text,
+    )
+
+    effects_chain_config = None
+    if data.effects_chain is not None:
+        effects_chain_config = [e.model_dump() for e in data.effects_chain]
+    else:
+        import json as _json
+
+        profile_obj = db.query(DBVoiceProfile).filter_by(id=data.profile_id).first()
+        if profile_obj and profile_obj.effects_chain:
+            try:
+                effects_chain_config = _json.loads(profile_obj.effects_chain)
+            except Exception:
+                pass
+
+    enqueue_generation(
+        run_generation(
+            generation_id=generation_id,
+            profile_id=data.profile_id,
+            text=data.text,
+            language=data.language,
+            engine=engine,
+            model_size=model_size,
+            seed=data.seed,
+            normalize=data.normalize,
+            effects_chain=effects_chain_config,
+            instruct=data.instruct,
+            mode="generate",
+            max_chunk_chars=data.max_chunk_chars,
+            crossfade_ms=data.crossfade_ms,
+        )
+    )
+
+    return generation
+
+
+@router.post("/generate/{generation_id}/retry", response_model=models.GenerationResponse)
+async def retry_generation(generation_id: str, db: Session = Depends(get_db)):
+    """Retry a failed generation using the same parameters."""
+    gen = db.query(DBGeneration).filter_by(id=generation_id).first()
+    if not gen:
+        raise HTTPException(status_code=404, detail="Generation not found")
+
+    if (gen.status or "completed") != "failed":
+        raise HTTPException(status_code=400, detail="Only failed generations can be retried")
+
+    gen.status = "generating"
+    gen.error = None
+    gen.audio_path = ""
+    gen.duration = 0
+    db.commit()
+    db.refresh(gen)
+
+    task_manager = get_task_manager()
+    task_manager.start_generation(
+        task_id=generation_id,
+        profile_id=gen.profile_id,
+        text=gen.text,
+    )
+
+    enqueue_generation(
+        run_generation(
+            generation_id=generation_id,
+            profile_id=gen.profile_id,
+            text=gen.text,
+            language=gen.language,
+            engine=gen.engine or "qwen",
+            model_size=gen.model_size or "1.7B",
+            seed=gen.seed,
+            instruct=gen.instruct,
+            mode="retry",
+        )
+    )
+
+    return models.GenerationResponse.model_validate(gen)
+
+
+@router.post(
+    "/generate/{generation_id}/regenerate",
+    response_model=models.GenerationResponse,
+)
+async def regenerate_generation(generation_id: str, db: Session = Depends(get_db)):
+    """Re-run TTS with the same parameters and save the result as a new version."""
+    gen = db.query(DBGeneration).filter_by(id=generation_id).first()
+    if not gen:
+        raise HTTPException(status_code=404, detail="Generation not found")
+    if (gen.status or "completed") != "completed":
+        raise HTTPException(status_code=400, detail="Generation must be completed to regenerate")
+
+    gen.status = "generating"
+    gen.error = None
+    db.commit()
+    db.refresh(gen)
+
+    task_manager = get_task_manager()
+    task_manager.start_generation(
+        task_id=generation_id,
+        profile_id=gen.profile_id,
+        text=gen.text,
+    )
+
+    version_id = str(uuid.uuid4())
+
+    enqueue_generation(
+        run_generation(
+            generation_id=generation_id,
+            profile_id=gen.profile_id,
+            text=gen.text,
+            language=gen.language,
+            engine=gen.engine or "qwen",
+            model_size=gen.model_size or "1.7B",
+            seed=gen.seed,
+            instruct=gen.instruct,
+            mode="regenerate",
+            version_id=version_id,
+        )
+    )
+
+    return models.GenerationResponse.model_validate(gen)
+
+
+@router.get("/generate/{generation_id}/status")
+async def get_generation_status(generation_id: str, db: Session = Depends(get_db)):
+    """SSE endpoint that streams generation status updates."""
+    import json
+
+    async def event_stream():
+        try:
+            while True:
+                db.expire_all()
+                gen = db.query(DBGeneration).filter_by(id=generation_id).first()
+                if not gen:
+                    yield f"data: {json.dumps({'status': 'not_found', 'id': generation_id})}\n\n"
+                    return
+
+                payload = {
+                    "id": gen.id,
+                    "status": gen.status or "completed",
+                    "duration": gen.duration,
+                    "error": gen.error,
+                }
+                yield f"data: {json.dumps(payload)}\n\n"
+
+                if (gen.status or "completed") in ("completed", "failed"):
+                    return
+
+                await asyncio.sleep(1)
+        except (BrokenPipeError, ConnectionResetError, asyncio.CancelledError):
+            logger.debug("SSE client disconnected for generation %s", generation_id)
+
+    return StreamingResponse(
+        event_stream(),
+        media_type="text/event-stream",
+        headers={
+            "Cache-Control": "no-cache",
+            "Connection": "keep-alive",
+            "X-Accel-Buffering": "no",
+        },
+    )
+
+
+@router.post("/generate/stream")
+async def stream_speech(
+    data: models.GenerationRequest,
+    db: Session = Depends(get_db),
+):
+    """Generate speech and stream the WAV audio directly without saving to disk."""
+    from ..backends import get_tts_backend_for_engine, ensure_model_cached_or_raise, load_engine_model, engine_needs_trim
+
+    profile = await profiles.get_profile(data.profile_id, db)
+    if not profile:
+        raise HTTPException(status_code=404, detail="Profile not found")
+
+    engine = data.engine or "qwen"
+    tts_model = get_tts_backend_for_engine(engine)
+    model_size = data.model_size or "1.7B"
+
+    await ensure_model_cached_or_raise(engine, model_size)
+    await load_engine_model(engine, model_size)
+
+    voice_prompt = await profiles.create_voice_prompt_for_profile(
+        data.profile_id,
+        db,
+        engine=engine,
+    )
+
+    from ..utils.chunked_tts import generate_chunked
+
+    trim_fn = None
+    if engine_needs_trim(engine):
+        from ..utils.audio import trim_tts_output
+
+        trim_fn = trim_tts_output
+
+    audio, sample_rate = await generate_chunked(
+        tts_model,
+        data.text,
+        voice_prompt,
+        language=data.language,
+        seed=data.seed,
+        instruct=data.instruct,
+        max_chunk_chars=data.max_chunk_chars,
+        crossfade_ms=data.crossfade_ms,
+        trim_fn=trim_fn,
+    )
+
+    if data.normalize:
+        from ..utils.audio import normalize_audio
+
+        audio = normalize_audio(audio)
+
+    wav_bytes = tts.audio_to_wav_bytes(audio, sample_rate)
+
+    async def _wav_stream():
+        try:
+            chunk_size = 64 * 1024
+            for i in range(0, len(wav_bytes), chunk_size):
+                yield wav_bytes[i : i + chunk_size]
+        except (BrokenPipeError, ConnectionResetError, asyncio.CancelledError):
+            logger.debug("Client disconnected during audio stream")
+
+    return StreamingResponse(
+        _wav_stream(),
+        media_type="audio/wav",
+        headers={"Content-Disposition": 'attachment; filename="speech.wav"'},
+    )

backend/routes/health.py

@@ -0,0 +1,233 @@
+"""Health and infrastructure endpoints."""
+
+import asyncio
+import os
+import signal
+from pathlib import Path
+
+import torch
+from fastapi import APIRouter, Depends
+from fastapi.responses import FileResponse
+from sqlalchemy.orm import Session
+
+from .. import config, models
+from ..services import tts
+from ..database import get_db
+from ..utils.platform_detect import get_backend_type
+
+router = APIRouter()
+
+# Frontend build directory — present in Docker, absent in dev/API-only mode
+_frontend_dir = Path(__file__).resolve().parent.parent.parent / "frontend"
+
+
+@router.get("/")
+async def root():
+    """Root endpoint — serves SPA index.html in Docker, JSON otherwise."""
+    from .. import __version__
+
+    index = _frontend_dir / "index.html"
+    if index.is_file():
+        return FileResponse(index, media_type="text/html")
+    return {"message": "voicebox API", "version": __version__}
+
+
+@router.post("/shutdown")
+async def shutdown():
+    """Gracefully shutdown the server."""
+
+    async def shutdown_async():
+        await asyncio.sleep(0.1)
+        os.kill(os.getpid(), signal.SIGTERM)
+
+    asyncio.create_task(shutdown_async())
+    return {"message": "Shutting down..."}
+
+
+@router.post("/watchdog/disable")
+async def watchdog_disable():
+    """Disable the parent process watchdog so the server keeps running."""
+    from backend.server import disable_watchdog
+
+    disable_watchdog()
+    return {"message": "Watchdog disabled"}
+
+
+@router.get("/health", response_model=models.HealthResponse)
+async def health():
+    """Health check endpoint."""
+    from huggingface_hub import constants as hf_constants
+    from pathlib import Path
+
+    tts_model = tts.get_tts_model()
+    backend_type = get_backend_type()
+
+    has_cuda = torch.cuda.is_available()
+    has_mps = hasattr(torch.backends, "mps") and torch.backends.mps.is_available()
+
+    has_xpu = False
+    xpu_name = None
+    try:
+        import intel_extension_for_pytorch as ipex  # noqa: F401 -- side-effect import enables XPU
+
+        if hasattr(torch, "xpu") and torch.xpu.is_available():
+            has_xpu = True
+            try:
+                xpu_name = torch.xpu.get_device_name(0)
+            except Exception:
+                xpu_name = "Intel GPU"
+    except ImportError:
+        pass
+
+    has_directml = False
+    directml_name = None
+    try:
+        import torch_directml
+
+        if torch_directml.device_count() > 0:
+            has_directml = True
+            try:
+                directml_name = torch_directml.device_name(0)
+            except Exception:
+                directml_name = "DirectML GPU"
+    except ImportError:
+        pass
+
+    gpu_available = has_cuda or has_mps or has_xpu or has_directml or backend_type == "mlx"
+
+    gpu_type = None
+    if has_cuda:
+        gpu_type = f"CUDA ({torch.cuda.get_device_name(0)})"
+    elif has_mps:
+        gpu_type = "MPS (Apple Silicon)"
+    elif backend_type == "mlx":
+        gpu_type = "Metal (Apple Silicon via MLX)"
+    elif has_xpu:
+        gpu_type = f"XPU ({xpu_name})"
+    elif has_directml:
+        gpu_type = f"DirectML ({directml_name})"
+
+    vram_used = None
+    if has_cuda:
+        vram_used = torch.cuda.memory_allocated() / 1024 / 1024
+
+    model_loaded = False
+    model_size = None
+    try:
+        if tts_model.is_loaded():
+            model_loaded = True
+            model_size = getattr(tts_model, "_current_model_size", None)
+            if not model_size:
+                model_size = getattr(tts_model, "model_size", None)
+    except Exception:
+        model_loaded = False
+        model_size = None
+
+    model_downloaded = None
+    try:
+        from ..backends import get_model_config
+
+        default_config = get_model_config("qwen-tts-1.7B")
+        default_model_id = default_config.hf_repo_id if default_config else "Qwen/Qwen3-TTS-12Hz-1.7B-Base"
+
+        try:
+            from huggingface_hub import scan_cache_dir
+
+            cache_info = scan_cache_dir()
+            for repo in cache_info.repos:
+                if repo.repo_id == default_model_id:
+                    model_downloaded = True
+                    break
+        except (ImportError, Exception):
+            cache_dir = hf_constants.HF_HUB_CACHE
+            repo_cache = Path(cache_dir) / ("models--" + default_model_id.replace("/", "--"))
+            if repo_cache.exists():
+                has_model_files = (
+                    any(repo_cache.rglob("*.bin"))
+                    or any(repo_cache.rglob("*.safetensors"))
+                    or any(repo_cache.rglob("*.pt"))
+                    or any(repo_cache.rglob("*.pth"))
+                    or any(repo_cache.rglob("*.npz"))
+                )
+                model_downloaded = has_model_files
+    except Exception:
+        pass
+
+    return models.HealthResponse(
+        status="healthy",
+        model_loaded=model_loaded,
+        model_downloaded=model_downloaded,
+        model_size=model_size,
+        gpu_available=gpu_available,
+        gpu_type=gpu_type,
+        vram_used_mb=vram_used,
+        backend_type=backend_type,
+        backend_variant=os.environ.get("VOICEBOX_BACKEND_VARIANT", "cuda" if torch.cuda.is_available() else "cpu"),
+    )
+
+
+@router.get("/health/filesystem", response_model=models.FilesystemHealthResponse)
+async def filesystem_health():
+    """Check filesystem health: directory existence, write permissions, and disk space."""
+    import shutil
+
+    dirs_to_check = {
+        "generations": config.get_generations_dir(),
+        "profiles": config.get_profiles_dir(),
+        "data": config.get_data_dir(),
+    }
+
+    checks: list[models.DirectoryCheck] = []
+    all_ok = True
+
+    for _label, dir_path in dirs_to_check.items():
+        exists = dir_path.exists()
+        writable = False
+        error = None
+        if exists:
+            probe = dir_path / ".voicebox_probe"
+            try:
+                probe.write_text("ok")
+                probe.unlink()
+                writable = True
+            except PermissionError:
+                error = "Permission denied"
+            except OSError as e:
+                error = str(e)
+            finally:
+                try:
+                    probe.unlink(missing_ok=True)
+                except Exception:
+                    pass
+        else:
+            error = "Directory does not exist"
+
+        if not exists or not writable:
+            all_ok = False
+
+        checks.append(
+            models.DirectoryCheck(
+                path=str(dir_path.resolve()),
+                exists=exists,
+                writable=writable,
+                error=error,
+            )
+        )
+
+    disk_free_mb = None
+    disk_total_mb = None
+    try:
+        usage = shutil.disk_usage(str(config.get_data_dir()))
+        disk_free_mb = round(usage.free / (1024 * 1024), 1)
+        disk_total_mb = round(usage.total / (1024 * 1024), 1)
+        if disk_free_mb < 500:
+            all_ok = False
+    except OSError:
+        all_ok = False
+
+    return models.FilesystemHealthResponse(
+        healthy=all_ok,
+        disk_free_mb=disk_free_mb,
+        disk_total_mb=disk_total_mb,
+        directories=checks,
+    )

backend/routes/history.py

@@ -0,0 +1,178 @@
+"""Generation history endpoints."""
+
+import io
+from pathlib import Path
+
+from fastapi import APIRouter, Depends, File, HTTPException, UploadFile
+from fastapi.responses import FileResponse, StreamingResponse
+from sqlalchemy.orm import Session
+
+from .. import models
+from ..services import export_import, history
+from ..app import safe_content_disposition
+from ..database import Generation as DBGeneration, VoiceProfile as DBVoiceProfile, get_db
+
+router = APIRouter()
+
+
+@router.get("/history", response_model=models.HistoryListResponse)
+async def list_history(
+    profile_id: str | None = None,
+    search: str | None = None,
+    limit: int = 50,
+    offset: int = 0,
+    db: Session = Depends(get_db),
+):
+    """List generation history with optional filters."""
+    query = models.HistoryQuery(
+        profile_id=profile_id,
+        search=search,
+        limit=limit,
+        offset=offset,
+    )
+    return await history.list_generations(query, db)
+
+
+@router.get("/history/stats")
+async def get_stats(db: Session = Depends(get_db)):
+    """Get generation statistics."""
+    return await history.get_generation_stats(db)
+
+
+@router.post("/history/import")
+async def import_generation(
+    file: UploadFile = File(...),
+    db: Session = Depends(get_db),
+):
+    """Import a generation from a ZIP archive."""
+    MAX_FILE_SIZE = 50 * 1024 * 1024
+
+    content = await file.read()
+
+    if len(content) > MAX_FILE_SIZE:
+        raise HTTPException(
+            status_code=400, detail=f"File too large. Maximum size is {MAX_FILE_SIZE / (1024 * 1024)}MB"
+        )
+
+    try:
+        result = await export_import.import_generation_from_zip(content, db)
+        return result
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.get("/history/{generation_id}", response_model=models.HistoryResponse)
+async def get_generation(
+    generation_id: str,
+    db: Session = Depends(get_db),
+):
+    """Get a generation by ID."""
+    result = (
+        db.query(DBGeneration, DBVoiceProfile.name.label("profile_name"))
+        .join(DBVoiceProfile, DBGeneration.profile_id == DBVoiceProfile.id)
+        .filter(DBGeneration.id == generation_id)
+        .first()
+    )
+
+    if not result:
+        raise HTTPException(status_code=404, detail="Generation not found")
+
+    gen, profile_name = result
+    return models.HistoryResponse(
+        id=gen.id,
+        profile_id=gen.profile_id,
+        profile_name=profile_name,
+        text=gen.text,
+        language=gen.language,
+        audio_path=gen.audio_path,
+        duration=gen.duration,
+        seed=gen.seed,
+        instruct=gen.instruct,
+        created_at=gen.created_at,
+    )
+
+
+@router.post("/history/{generation_id}/favorite")
+async def toggle_favorite(
+    generation_id: str,
+    db: Session = Depends(get_db),
+):
+    """Toggle the favorite status of a generation."""
+    gen = db.query(DBGeneration).filter_by(id=generation_id).first()
+    if not gen:
+        raise HTTPException(status_code=404, detail="Generation not found")
+    gen.is_favorited = not gen.is_favorited
+    db.commit()
+    return {"is_favorited": gen.is_favorited}
+
+
+@router.delete("/history/{generation_id}")
+async def delete_generation(
+    generation_id: str,
+    db: Session = Depends(get_db),
+):
+    """Delete a generation."""
+    success = await history.delete_generation(generation_id, db)
+    if not success:
+        raise HTTPException(status_code=404, detail="Generation not found")
+    return {"message": "Generation deleted successfully"}
+
+
+@router.get("/history/{generation_id}/export")
+async def export_generation(
+    generation_id: str,
+    db: Session = Depends(get_db),
+):
+    """Export a generation as a ZIP archive."""
+    generation = db.query(DBGeneration).filter_by(id=generation_id).first()
+    if not generation:
+        raise HTTPException(status_code=404, detail="Generation not found")
+
+    try:
+        zip_bytes = export_import.export_generation_to_zip(generation_id, db)
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+    safe_text = "".join(c for c in generation.text[:30] if c.isalnum() or c in (" ", "-", "_")).strip()
+    if not safe_text:
+        safe_text = "generation"
+    filename = f"generation-{safe_text}.voicebox.zip"
+
+    return StreamingResponse(
+        io.BytesIO(zip_bytes),
+        media_type="application/zip",
+        headers={"Content-Disposition": safe_content_disposition("attachment", filename)},
+    )
+
+
+@router.get("/history/{generation_id}/export-audio")
+async def export_generation_audio(
+    generation_id: str,
+    db: Session = Depends(get_db),
+):
+    """Export only the audio file from a generation."""
+    generation = db.query(DBGeneration).filter_by(id=generation_id).first()
+    if not generation:
+        raise HTTPException(status_code=404, detail="Generation not found")
+
+    if not generation.audio_path:
+        raise HTTPException(status_code=404, detail="Generation has no audio file")
+
+    audio_path = Path(generation.audio_path)
+    if not audio_path.is_file():
+        raise HTTPException(status_code=404, detail="Audio file not found")
+
+    safe_text = "".join(c for c in generation.text[:30] if c.isalnum() or c in (" ", "-", "_")).strip()
+    if not safe_text:
+        safe_text = "generation"
+    filename = f"{safe_text}.wav"
+
+    return FileResponse(
+        audio_path,
+        media_type="audio/wav",
+        headers={"Content-Disposition": safe_content_disposition("attachment", filename)},
+    )

backend/routes/models.py

@@ -0,0 +1,474 @@
+"""Model management endpoints."""
+
+import asyncio
+import shutil
+from pathlib import Path
+
+from fastapi import APIRouter, Depends, HTTPException
+from fastapi.responses import StreamingResponse
+from sqlalchemy.orm import Session
+
+from .. import models
+from ..utils.platform_detect import get_backend_type
+from ..services.task_queue import create_background_task
+from ..utils.progress import get_progress_manager
+from ..utils.tasks import get_task_manager
+
+router = APIRouter()
+
+
+def _get_dir_size(path: Path) -> int:
+    """Get total size of a directory in bytes."""
+    total = 0
+    for f in path.rglob("*"):
+        if f.is_file():
+            total += f.stat().st_size
+    return total
+
+
+def _copy_with_progress(src: Path, dst: Path, progress_manager, copied_so_far: int, total_bytes: int) -> int:
+    """Copy a directory tree with byte-level progress tracking."""
+    dst.mkdir(parents=True, exist_ok=True)
+    for item in src.iterdir():
+        dest_item = dst / item.name
+        if item.is_dir():
+            copied_so_far = _copy_with_progress(item, dest_item, progress_manager, copied_so_far, total_bytes)
+        else:
+            size = item.stat().st_size
+            shutil.copy2(str(item), str(dest_item))
+            copied_so_far += size
+            progress_manager.update_progress(
+                "migration",
+                copied_so_far,
+                total_bytes,
+                filename=item.name,
+                status="downloading",
+            )
+    return copied_so_far
+
+
+@router.post("/models/load")
+async def load_model(model_size: str = "1.7B"):
+    """Manually load TTS model."""
+    from ..services import tts
+
+    try:
+        tts_model = tts.get_tts_model()
+        await tts_model.load_model_async(model_size)
+        return {"message": f"Model {model_size} loaded successfully"}
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.post("/models/unload")
+async def unload_model():
+    """Unload the default Qwen TTS model to free memory."""
+    from ..services import tts
+
+    try:
+        tts.unload_tts_model()
+        return {"message": "Model unloaded successfully"}
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.post("/models/{model_name}/unload")
+async def unload_model_by_name(model_name: str):
+    """Unload a specific model from memory without deleting it from disk."""
+    from ..backends import get_model_config, unload_model_by_config
+
+    config = get_model_config(model_name)
+    if not config:
+        raise HTTPException(status_code=400, detail=f"Unknown model: {model_name}")
+
+    try:
+        was_loaded = unload_model_by_config(config)
+        if not was_loaded:
+            return {"message": f"Model {model_name} is not loaded"}
+        return {"message": f"Model {model_name} unloaded successfully"}
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e)) from e
+
+
+@router.get("/models/progress/{model_name}")
+async def get_model_progress(model_name: str):
+    """Get model download progress via Server-Sent Events."""
+    progress_manager = get_progress_manager()
+
+    async def event_generator():
+        async for event in progress_manager.subscribe(model_name):
+            yield event
+
+    return StreamingResponse(
+        event_generator(),
+        media_type="text/event-stream",
+        headers={
+            "Cache-Control": "no-cache",
+            "Connection": "keep-alive",
+            "X-Accel-Buffering": "no",
+        },
+    )
+
+
+@router.get("/models/cache-dir")
+async def get_models_cache_dir():
+    """Get the path to the HuggingFace model cache directory."""
+    from huggingface_hub import constants as hf_constants
+
+    return {"path": str(Path(hf_constants.HF_HUB_CACHE))}
+
+
+@router.post("/models/migrate")
+async def migrate_models(request: models.ModelMigrateRequest):
+    """Move all downloaded models to a new directory with byte-level progress via SSE."""
+    from huggingface_hub import constants as hf_constants
+
+    source = Path(hf_constants.HF_HUB_CACHE)
+    destination = Path(request.destination)
+
+    if not source.exists():
+        raise HTTPException(status_code=404, detail="Current model cache directory not found")
+
+    if source.resolve() == destination.resolve():
+        raise HTTPException(status_code=400, detail="Source and destination are the same directory")
+
+    if destination.resolve().is_relative_to(source.resolve()):
+        raise HTTPException(status_code=400, detail="Destination cannot be inside the current cache directory")
+
+    model_dirs = [d for d in source.iterdir() if d.name.startswith("models--") and d.is_dir()]
+    if not model_dirs:
+        return {"moved": 0, "errors": [], "source": str(source), "destination": str(destination)}
+
+    destination.mkdir(parents=True, exist_ok=True)
+
+    progress_manager = get_progress_manager()
+
+    same_fs = False
+    try:
+        same_fs = source.stat().st_dev == destination.stat().st_dev
+    except OSError:
+        pass
+
+    async def migrate_background():
+        moved = 0
+        errors = []
+        try:
+            if same_fs:
+                total = len(model_dirs)
+                for i, item in enumerate(model_dirs):
+                    dest_item = destination / item.name
+                    try:
+                        if dest_item.exists():
+                            shutil.rmtree(dest_item)
+                        shutil.move(str(item), str(dest_item))
+                        moved += 1
+                        progress_manager.update_progress(
+                            "migration",
+                            i + 1,
+                            total,
+                            filename=item.name,
+                            status="downloading",
+                        )
+                    except Exception as e:
+                        errors.append(f"{item.name}: {str(e)}")
+            else:
+                total_bytes = sum(_get_dir_size(d) for d in model_dirs)
+                progress_manager.update_progress(
+                    "migration", 0, total_bytes, filename="Calculating...", status="downloading"
+                )
+
+                copied = 0
+                for item in model_dirs:
+                    dest_item = destination / item.name
+                    try:
+                        if dest_item.exists():
+                            shutil.rmtree(dest_item)
+                        copied = await asyncio.to_thread(
+                            _copy_with_progress, item, dest_item, progress_manager, copied, total_bytes
+                        )
+                        await asyncio.to_thread(shutil.rmtree, str(item))
+                        moved += 1
+                    except Exception as e:
+                        errors.append(f"{item.name}: {str(e)}")
+
+            progress_manager.update_progress("migration", 1, 1, status="complete")
+            progress_manager.mark_complete("migration")
+        except Exception as e:
+            progress_manager.update_progress("migration", 0, 0, status="error")
+            progress_manager.mark_error("migration", str(e))
+
+    create_background_task(migrate_background())
+
+    return {"source": str(source), "destination": str(destination)}
+
+
+@router.get("/models/migrate/progress")
+async def get_migration_progress():
+    """Get model migration progress via Server-Sent Events."""
+    progress_manager = get_progress_manager()
+
+    async def event_generator():
+        async for event in progress_manager.subscribe("migration"):
+            yield event
+
+    return StreamingResponse(
+        event_generator(),
+        media_type="text/event-stream",
+        headers={
+            "Cache-Control": "no-cache",
+            "Connection": "keep-alive",
+            "X-Accel-Buffering": "no",
+        },
+    )
+
+
+@router.get("/models/status", response_model=models.ModelStatusListResponse)
+async def get_model_status():
+    """Get status of all available models."""
+    from huggingface_hub import constants as hf_constants
+
+    backend_type = get_backend_type()
+    task_manager = get_task_manager()
+
+    active_download_names = {task.model_name for task in task_manager.get_active_downloads()}
+
+    try:
+        from huggingface_hub import scan_cache_dir
+
+        use_scan_cache = True
+    except ImportError:
+        use_scan_cache = False
+
+    from ..backends import get_all_model_configs, check_model_loaded
+
+    registry_configs = get_all_model_configs()
+    model_configs = [
+        {
+            "model_name": cfg.model_name,
+            "display_name": cfg.display_name,
+            "hf_repo_id": cfg.hf_repo_id,
+            "model_size": cfg.model_size,
+            "check_loaded": lambda c=cfg: check_model_loaded(c),
+        }
+        for cfg in registry_configs
+    ]
+
+    model_to_repo = {cfg["model_name"]: cfg["hf_repo_id"] for cfg in model_configs}
+    active_download_repos = {model_to_repo.get(name) for name in active_download_names if name in model_to_repo}
+
+    cache_info = None
+    if use_scan_cache:
+        try:
+            cache_info = scan_cache_dir()
+        except Exception:
+            pass
+
+    statuses = []
+
+    for config in model_configs:
+        try:
+            downloaded = False
+            size_mb = None
+            loaded = False
+
+            if cache_info:
+                repo_id = config["hf_repo_id"]
+                for repo in cache_info.repos:
+                    if repo.repo_id == repo_id:
+                        has_model_weights = False
+                        for rev in repo.revisions:
+                            for f in rev.files:
+                                fname = f.file_name.lower()
+                                if fname.endswith((".safetensors", ".bin", ".pt", ".pth", ".npz")):
+                                    has_model_weights = True
+                                    break
+                            if has_model_weights:
+                                break
+
+                        has_incomplete = False
+                        try:
+                            cache_dir = hf_constants.HF_HUB_CACHE
+                            blobs_dir = Path(cache_dir) / ("models--" + repo_id.replace("/", "--")) / "blobs"
+                            if blobs_dir.exists():
+                                has_incomplete = any(blobs_dir.glob("*.incomplete"))
+                        except Exception:
+                            pass
+
+                        if has_model_weights and not has_incomplete:
+                            downloaded = True
+                            try:
+                                total_size = sum(revision.size_on_disk for revision in repo.revisions)
+                                size_mb = total_size / (1024 * 1024)
+                            except Exception:
+                                pass
+                        break
+
+            if not downloaded:
+                try:
+                    cache_dir = hf_constants.HF_HUB_CACHE
+                    repo_cache = Path(cache_dir) / ("models--" + config["hf_repo_id"].replace("/", "--"))
+
+                    if repo_cache.exists():
+                        blobs_dir = repo_cache / "blobs"
+                        has_incomplete = blobs_dir.exists() and any(blobs_dir.glob("*.incomplete"))
+
+                        if not has_incomplete:
+                            snapshots_dir = repo_cache / "snapshots"
+                            has_model_files = False
+                            if snapshots_dir.exists():
+                                has_model_files = (
+                                    any(snapshots_dir.rglob("*.bin"))
+                                    or any(snapshots_dir.rglob("*.safetensors"))
+                                    or any(snapshots_dir.rglob("*.pt"))
+                                    or any(snapshots_dir.rglob("*.pth"))
+                                    or any(snapshots_dir.rglob("*.npz"))
+                                )
+
+                            if has_model_files:
+                                downloaded = True
+                                try:
+                                    total_size = sum(
+                                        f.stat().st_size
+                                        for f in repo_cache.rglob("*")
+                                        if f.is_file() and not f.name.endswith(".incomplete")
+                                    )
+                                    size_mb = total_size / (1024 * 1024)
+                                except Exception:
+                                    pass
+                except Exception:
+                    pass
+
+            try:
+                loaded = config["check_loaded"]()
+            except Exception:
+                loaded = False
+
+            is_downloading = config["hf_repo_id"] in active_download_repos
+
+            if is_downloading:
+                downloaded = False
+                size_mb = None
+
+            statuses.append(
+                models.ModelStatus(
+                    model_name=config["model_name"],
+                    display_name=config["display_name"],
+                    hf_repo_id=config["hf_repo_id"],
+                    downloaded=downloaded,
+                    downloading=is_downloading,
+                    size_mb=size_mb,
+                    loaded=loaded,
+                )
+            )
+        except Exception:
+            try:
+                loaded = config["check_loaded"]()
+            except Exception:
+                loaded = False
+
+            is_downloading = config["hf_repo_id"] in active_download_repos
+
+            statuses.append(
+                models.ModelStatus(
+                    model_name=config["model_name"],
+                    display_name=config["display_name"],
+                    hf_repo_id=config["hf_repo_id"],
+                    downloaded=False,
+                    downloading=is_downloading,
+                    size_mb=None,
+                    loaded=loaded,
+                )
+            )
+
+    return models.ModelStatusListResponse(models=statuses)
+
+
+@router.post("/models/download")
+async def trigger_model_download(request: models.ModelDownloadRequest):
+    """Trigger download of a specific model."""
+    from ..backends import get_model_config, get_model_load_func
+
+    task_manager = get_task_manager()
+    progress_manager = get_progress_manager()
+
+    config = get_model_config(request.model_name)
+    if not config:
+        raise HTTPException(status_code=400, detail=f"Unknown model: {request.model_name}")
+
+    load_func = get_model_load_func(config)
+
+    async def download_in_background():
+        try:
+            result = load_func()
+            if asyncio.iscoroutine(result):
+                await result
+            task_manager.complete_download(request.model_name)
+        except Exception as e:
+            task_manager.error_download(request.model_name, str(e))
+
+    task_manager.start_download(request.model_name)
+
+    progress_manager.update_progress(
+        model_name=request.model_name,
+        current=0,
+        total=0,
+        filename="Connecting to HuggingFace...",
+        status="downloading",
+    )
+
+    create_background_task(download_in_background())
+
+    return {"message": f"Model {request.model_name} download started"}
+
+
+@router.post("/models/download/cancel")
+async def cancel_model_download(request: models.ModelDownloadRequest):
+    """Cancel or dismiss an errored/stale download task."""
+    task_manager = get_task_manager()
+    progress_manager = get_progress_manager()
+
+    removed = task_manager.cancel_download(request.model_name)
+
+    progress_removed = False
+    with progress_manager._lock:
+        if request.model_name in progress_manager._progress:
+            del progress_manager._progress[request.model_name]
+            progress_removed = True
+
+    if removed or progress_removed:
+        return {"message": f"Download task for {request.model_name} cancelled"}
+    return {"message": f"No active task found for {request.model_name}"}
+
+
+@router.delete("/models/{model_name}")
+async def delete_model(model_name: str):
+    """Delete a downloaded model from the HuggingFace cache."""
+    from huggingface_hub import constants as hf_constants
+    from ..backends import get_model_config, unload_model_by_config
+
+    config = get_model_config(model_name)
+    if not config:
+        raise HTTPException(status_code=400, detail=f"Unknown model: {model_name}")
+
+    hf_repo_id = config.hf_repo_id
+
+    try:
+        unload_model_by_config(config)
+
+        cache_dir = hf_constants.HF_HUB_CACHE
+        repo_cache_dir = Path(cache_dir) / ("models--" + hf_repo_id.replace("/", "--"))
+
+        if not repo_cache_dir.exists():
+            raise HTTPException(status_code=404, detail=f"Model {model_name} not found in cache")
+
+        try:
+            shutil.rmtree(repo_cache_dir)
+        except OSError as e:
+            raise HTTPException(status_code=500, detail=f"Failed to delete model cache directory: {str(e)}")
+
+        return {"message": f"Model {model_name} deleted successfully"}
+
+    except HTTPException:
+        raise
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=f"Failed to delete model: {str(e)}")

backend/routes/profiles.py

@@ -0,0 +1,321 @@
+"""Voice profile endpoints."""
+
+import io
+import tempfile
+from datetime import datetime
+from pathlib import Path
+
+from fastapi import APIRouter, Depends, File, Form, HTTPException, UploadFile
+from fastapi.responses import FileResponse, StreamingResponse
+from sqlalchemy.orm import Session
+
+from .. import config, models
+from ..app import safe_content_disposition
+from ..database import VoiceProfile as DBVoiceProfile, get_db
+from ..services import channels, export_import, profiles
+from ..services.profiles import _profile_to_response
+
+router = APIRouter()
+
+
+@router.post("/profiles", response_model=models.VoiceProfileResponse)
+async def create_profile(
+    data: models.VoiceProfileCreate,
+    db: Session = Depends(get_db),
+):
+    """Create a new voice profile."""
+    try:
+        return await profiles.create_profile(data, db)
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    except Exception as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.get("/profiles", response_model=list[models.VoiceProfileResponse])
+async def list_profiles(db: Session = Depends(get_db)):
+    """List all voice profiles."""
+    return await profiles.list_profiles(db)
+
+
+@router.post("/profiles/import", response_model=models.VoiceProfileResponse)
+async def import_profile(
+    file: UploadFile = File(...),
+    db: Session = Depends(get_db),
+):
+    """Import a voice profile from a ZIP archive."""
+    MAX_FILE_SIZE = 100 * 1024 * 1024
+
+    content = await file.read()
+
+    if len(content) > MAX_FILE_SIZE:
+        raise HTTPException(
+            status_code=400, detail=f"File too large. Maximum size is {MAX_FILE_SIZE / (1024 * 1024)}MB"
+        )
+
+    try:
+        profile = await export_import.import_profile_from_zip(content, db)
+        return profile
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.get("/profiles/{profile_id}", response_model=models.VoiceProfileResponse)
+async def get_profile(
+    profile_id: str,
+    db: Session = Depends(get_db),
+):
+    """Get a voice profile by ID."""
+    profile = await profiles.get_profile(profile_id, db)
+    if not profile:
+        raise HTTPException(status_code=404, detail="Profile not found")
+    return profile
+
+
+@router.put("/profiles/{profile_id}", response_model=models.VoiceProfileResponse)
+async def update_profile(
+    profile_id: str,
+    data: models.VoiceProfileCreate,
+    db: Session = Depends(get_db),
+):
+    """Update a voice profile."""
+    try:
+        profile = await profiles.update_profile(profile_id, data, db)
+        if not profile:
+            raise HTTPException(status_code=404, detail="Profile not found")
+        return profile
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.delete("/profiles/{profile_id}")
+async def delete_profile(
+    profile_id: str,
+    db: Session = Depends(get_db),
+):
+    """Delete a voice profile."""
+    success = await profiles.delete_profile(profile_id, db)
+    if not success:
+        raise HTTPException(status_code=404, detail="Profile not found")
+    return {"message": "Profile deleted successfully"}
+
+
+SAMPLE_MAX_FILE_SIZE = 50 * 1024 * 1024  # 50 MB
+SAMPLE_UPLOAD_CHUNK_SIZE = 1024 * 1024  # 1 MB
+
+
+@router.post("/profiles/{profile_id}/samples", response_model=models.ProfileSampleResponse)
+async def add_profile_sample(
+    profile_id: str,
+    file: UploadFile = File(...),
+    reference_text: str = Form(...),
+    db: Session = Depends(get_db),
+):
+    """Add a sample to a voice profile."""
+    _allowed_audio_exts = {".wav", ".mp3", ".m4a", ".ogg", ".flac", ".aac", ".webm", ".opus"}
+    _uploaded_ext = Path(file.filename or "").suffix.lower()
+    file_suffix = _uploaded_ext if _uploaded_ext in _allowed_audio_exts else ".wav"
+
+    with tempfile.NamedTemporaryFile(suffix=file_suffix, delete=False) as tmp:
+        total_size = 0
+        while chunk := await file.read(SAMPLE_UPLOAD_CHUNK_SIZE):
+            total_size += len(chunk)
+            if total_size > SAMPLE_MAX_FILE_SIZE:
+                Path(tmp.name).unlink(missing_ok=True)
+                raise HTTPException(
+                    status_code=413,
+                    detail=f"File too large (max {SAMPLE_MAX_FILE_SIZE // (1024 * 1024)} MB)",
+                )
+            tmp.write(chunk)
+        tmp_path = tmp.name
+
+    try:
+        sample = await profiles.add_profile_sample(
+            profile_id,
+            tmp_path,
+            reference_text,
+            db,
+        )
+        return sample
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=f"Failed to process audio file: {str(e)}")
+    finally:
+        Path(tmp_path).unlink(missing_ok=True)
+
+
+@router.get("/profiles/{profile_id}/samples", response_model=list[models.ProfileSampleResponse])
+async def get_profile_samples(
+    profile_id: str,
+    db: Session = Depends(get_db),
+):
+    """Get all samples for a profile."""
+    return await profiles.get_profile_samples(profile_id, db)
+
+
+@router.delete("/profiles/samples/{sample_id}")
+async def delete_profile_sample(
+    sample_id: str,
+    db: Session = Depends(get_db),
+):
+    """Delete a profile sample."""
+    success = await profiles.delete_profile_sample(sample_id, db)
+    if not success:
+        raise HTTPException(status_code=404, detail="Sample not found")
+    return {"message": "Sample deleted successfully"}
+
+
+@router.put("/profiles/samples/{sample_id}", response_model=models.ProfileSampleResponse)
+async def update_profile_sample(
+    sample_id: str,
+    data: models.ProfileSampleUpdate,
+    db: Session = Depends(get_db),
+):
+    """Update a profile sample's reference text."""
+    sample = await profiles.update_profile_sample(sample_id, data.reference_text, db)
+    if not sample:
+        raise HTTPException(status_code=404, detail="Sample not found")
+    return sample
+
+
+@router.post("/profiles/{profile_id}/avatar", response_model=models.VoiceProfileResponse)
+async def upload_profile_avatar(
+    profile_id: str,
+    file: UploadFile = File(...),
+    db: Session = Depends(get_db),
+):
+    """Upload or update avatar image for a profile."""
+    with tempfile.NamedTemporaryFile(delete=False, suffix=Path(file.filename).suffix) as tmp:
+        content = await file.read()
+        tmp.write(content)
+        tmp_path = tmp.name
+
+    try:
+        profile = await profiles.upload_avatar(profile_id, tmp_path, db)
+        return profile
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    finally:
+        Path(tmp_path).unlink(missing_ok=True)
+
+
+@router.get("/profiles/{profile_id}/avatar")
+async def get_profile_avatar(
+    profile_id: str,
+    db: Session = Depends(get_db),
+):
+    """Get avatar image for a profile."""
+    profile = await profiles.get_profile(profile_id, db)
+    if not profile:
+        raise HTTPException(status_code=404, detail="Profile not found")
+
+    if not profile.avatar_path:
+        raise HTTPException(status_code=404, detail="No avatar found for this profile")
+
+    avatar_path = Path(profile.avatar_path)
+    if not avatar_path.exists():
+        raise HTTPException(status_code=404, detail="Avatar file not found")
+
+    return FileResponse(avatar_path)
+
+
+@router.delete("/profiles/{profile_id}/avatar")
+async def delete_profile_avatar(
+    profile_id: str,
+    db: Session = Depends(get_db),
+):
+    """Delete avatar image for a profile."""
+    success = await profiles.delete_avatar(profile_id, db)
+    if not success:
+        raise HTTPException(status_code=404, detail="Profile not found or no avatar to delete")
+    return {"message": "Avatar deleted successfully"}
+
+
+@router.get("/profiles/{profile_id}/export")
+async def export_profile(
+    profile_id: str,
+    db: Session = Depends(get_db),
+):
+    """Export a voice profile as a ZIP archive."""
+    try:
+        profile = await profiles.get_profile(profile_id, db)
+        if not profile:
+            raise HTTPException(status_code=404, detail="Profile not found")
+
+        zip_bytes = export_import.export_profile_to_zip(profile_id, db)
+
+        safe_name = "".join(c for c in profile.name if c.isalnum() or c in (" ", "-", "_")).strip()
+        if not safe_name:
+            safe_name = "profile"
+        filename = f"profile-{safe_name}.voicebox.zip"
+
+        return StreamingResponse(
+            io.BytesIO(zip_bytes),
+            media_type="application/zip",
+            headers={"Content-Disposition": safe_content_disposition("attachment", filename)},
+        )
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.get("/profiles/{profile_id}/channels")
+async def get_profile_channels(
+    profile_id: str,
+    db: Session = Depends(get_db),
+):
+    """Get list of channel IDs assigned to a profile."""
+    try:
+        channel_ids = await channels.get_profile_channels(profile_id, db)
+        return {"channel_ids": channel_ids}
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.put("/profiles/{profile_id}/channels")
+async def set_profile_channels(
+    profile_id: str,
+    data: models.ProfileChannelAssignment,
+    db: Session = Depends(get_db),
+):
+    """Set which channels a profile is assigned to."""
+    try:
+        await channels.set_profile_channels(profile_id, data, db)
+        return {"message": "Profile channels updated successfully"}
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.put("/profiles/{profile_id}/effects", response_model=models.VoiceProfileResponse)
+async def update_profile_effects(
+    profile_id: str,
+    data: models.ProfileEffectsUpdate,
+    db: Session = Depends(get_db),
+):
+    """Set or clear the default effects chain for a voice profile."""
+    import json as _json
+
+    profile = db.query(DBVoiceProfile).filter_by(id=profile_id).first()
+    if not profile:
+        raise HTTPException(status_code=404, detail="Profile not found")
+
+    if data.effects_chain is not None:
+        from ..utils.effects import validate_effects_chain
+
+        chain_dicts = [e.model_dump() for e in data.effects_chain]
+        error = validate_effects_chain(chain_dicts)
+        if error:
+            raise HTTPException(status_code=400, detail=error)
+        profile.effects_chain = _json.dumps(chain_dicts)
+    else:
+        profile.effects_chain = None
+
+    profile.updated_at = datetime.utcnow()
+    db.commit()
+    db.refresh(profile)
+
+    return _profile_to_response(profile)

backend/routes/stories.py

@@ -0,0 +1,223 @@
+"""Story endpoints."""
+
+import io
+
+from fastapi import APIRouter, Depends, HTTPException
+from fastapi.responses import StreamingResponse
+from sqlalchemy.orm import Session
+
+from .. import database, models
+from ..services import stories
+from ..app import safe_content_disposition
+from ..database import get_db
+
+router = APIRouter()
+
+
+@router.get("/stories", response_model=list[models.StoryResponse])
+async def list_stories(db: Session = Depends(get_db)):
+    """List all stories."""
+    return await stories.list_stories(db)
+
+
+@router.post("/stories", response_model=models.StoryResponse)
+async def create_story(
+    data: models.StoryCreate,
+    db: Session = Depends(get_db),
+):
+    """Create a new story."""
+    try:
+        return await stories.create_story(data, db)
+    except Exception as e:
+        raise HTTPException(status_code=400, detail=str(e))
+
+
+@router.get("/stories/{story_id}", response_model=models.StoryDetailResponse)
+async def get_story(
+    story_id: str,
+    db: Session = Depends(get_db),
+):
+    """Get a story with all its items."""
+    story = await stories.get_story(story_id, db)
+    if not story:
+        raise HTTPException(status_code=404, detail="Story not found")
+    return story
+
+
+@router.put("/stories/{story_id}", response_model=models.StoryResponse)
+async def update_story(
+    story_id: str,
+    data: models.StoryCreate,
+    db: Session = Depends(get_db),
+):
+    """Update a story."""
+    story = await stories.update_story(story_id, data, db)
+    if not story:
+        raise HTTPException(status_code=404, detail="Story not found")
+    return story
+
+
+@router.delete("/stories/{story_id}")
+async def delete_story(
+    story_id: str,
+    db: Session = Depends(get_db),
+):
+    """Delete a story."""
+    success = await stories.delete_story(story_id, db)
+    if not success:
+        raise HTTPException(status_code=404, detail="Story not found")
+    return {"message": "Story deleted successfully"}
+
+
+@router.post("/stories/{story_id}/items", response_model=models.StoryItemDetail)
+async def add_story_item(
+    story_id: str,
+    data: models.StoryItemCreate,
+    db: Session = Depends(get_db),
+):
+    """Add a generation to a story."""
+    item = await stories.add_item_to_story(story_id, data, db)
+    if not item:
+        raise HTTPException(status_code=404, detail="Story or generation not found")
+    return item
+
+
+@router.delete("/stories/{story_id}/items/{item_id}")
+async def remove_story_item(
+    story_id: str,
+    item_id: str,
+    db: Session = Depends(get_db),
+):
+    """Remove a story item from a story."""
+    success = await stories.remove_item_from_story(story_id, item_id, db)
+    if not success:
+        raise HTTPException(status_code=404, detail="Story item not found")
+    return {"message": "Item removed successfully"}
+
+
+@router.put("/stories/{story_id}/items/times")
+async def update_story_item_times(
+    story_id: str,
+    data: models.StoryItemBatchUpdate,
+    db: Session = Depends(get_db),
+):
+    """Update story item timecodes."""
+    success = await stories.update_story_item_times(story_id, data, db)
+    if not success:
+        raise HTTPException(status_code=400, detail="Invalid timecode update request")
+    return {"message": "Item timecodes updated successfully"}
+
+
+@router.put("/stories/{story_id}/items/reorder", response_model=list[models.StoryItemDetail])
+async def reorder_story_items(
+    story_id: str,
+    data: models.StoryItemReorder,
+    db: Session = Depends(get_db),
+):
+    """Reorder story items and recalculate timecodes."""
+    items = await stories.reorder_story_items(story_id, data.generation_ids, db)
+    if items is None:
+        raise HTTPException(
+            status_code=400, detail="Invalid reorder request - ensure all generation IDs belong to this story"
+        )
+    return items
+
+
+@router.put("/stories/{story_id}/items/{item_id}/move", response_model=models.StoryItemDetail)
+async def move_story_item(
+    story_id: str,
+    item_id: str,
+    data: models.StoryItemMove,
+    db: Session = Depends(get_db),
+):
+    """Move a story item (update position and/or track)."""
+    item = await stories.move_story_item(story_id, item_id, data, db)
+    if item is None:
+        raise HTTPException(status_code=404, detail="Story item not found")
+    return item
+
+
+@router.put("/stories/{story_id}/items/{item_id}/trim", response_model=models.StoryItemDetail)
+async def trim_story_item(
+    story_id: str,
+    item_id: str,
+    data: models.StoryItemTrim,
+    db: Session = Depends(get_db),
+):
+    """Trim a story item."""
+    item = await stories.trim_story_item(story_id, item_id, data, db)
+    if item is None:
+        raise HTTPException(status_code=404, detail="Story item not found or invalid trim values")
+    return item
+
+
+@router.post("/stories/{story_id}/items/{item_id}/split", response_model=list[models.StoryItemDetail])
+async def split_story_item(
+    story_id: str,
+    item_id: str,
+    data: models.StoryItemSplit,
+    db: Session = Depends(get_db),
+):
+    """Split a story item at a given time, creating two clips."""
+    items = await stories.split_story_item(story_id, item_id, data, db)
+    if items is None:
+        raise HTTPException(status_code=404, detail="Story item not found or invalid split point")
+    return items
+
+
+@router.post("/stories/{story_id}/items/{item_id}/duplicate", response_model=models.StoryItemDetail)
+async def duplicate_story_item(
+    story_id: str,
+    item_id: str,
+    db: Session = Depends(get_db),
+):
+    """Duplicate a story item."""
+    item = await stories.duplicate_story_item(story_id, item_id, db)
+    if item is None:
+        raise HTTPException(status_code=404, detail="Story item not found")
+    return item
+
+
+@router.put("/stories/{story_id}/items/{item_id}/version", response_model=models.StoryItemDetail)
+async def set_story_item_version(
+    story_id: str,
+    item_id: str,
+    data: models.StoryItemVersionUpdate,
+    db: Session = Depends(get_db),
+):
+    """Pin a story item to a specific generation version."""
+    item = await stories.set_story_item_version(story_id, item_id, data, db)
+    if item is None:
+        raise HTTPException(status_code=404, detail="Story item or version not found")
+    return item
+
+
+@router.get("/stories/{story_id}/export-audio")
+async def export_story_audio(
+    story_id: str,
+    db: Session = Depends(get_db),
+):
+    """Export story as single mixed audio file."""
+    try:
+        story = db.query(database.Story).filter_by(id=story_id).first()
+        if not story:
+            raise HTTPException(status_code=404, detail="Story not found")
+
+        audio_bytes = await stories.export_story_audio(story_id, db)
+        if not audio_bytes:
+            raise HTTPException(status_code=400, detail="Story has no audio items")
+
+        safe_name = "".join(c for c in story.name if c.isalnum() or c in (" ", "-", "_")).strip()
+        if not safe_name:
+            safe_name = "story"
+        filename = f"{safe_name}.wav"
+
+        return StreamingResponse(
+            io.BytesIO(audio_bytes),
+            media_type="audio/wav",
+            headers={"Content-Disposition": safe_content_disposition("attachment", filename)},
+        )
+    except HTTPException:
+        raise
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))

backend/routes/tasks.py

@@ -0,0 +1,125 @@
+"""Task and cache management endpoints."""
+
+from datetime import datetime
+
+from fastapi import APIRouter
+
+from .. import models
+from ..utils.cache import clear_voice_prompt_cache
+from ..utils.progress import get_progress_manager
+from ..utils.tasks import get_task_manager
+from fastapi import HTTPException
+
+router = APIRouter()
+
+
+@router.post("/tasks/clear")
+async def clear_all_tasks():
+    """Clear all download tasks and progress state."""
+    task_manager = get_task_manager()
+    progress_manager = get_progress_manager()
+
+    task_manager.clear_all()
+
+    with progress_manager._lock:
+        progress_manager._progress.clear()
+        progress_manager._last_notify_time.clear()
+        progress_manager._last_notify_progress.clear()
+
+    return {"message": "All task state cleared"}
+
+
+@router.post("/cache/clear")
+async def clear_cache():
+    """Clear all voice prompt caches (memory and disk)."""
+    try:
+        deleted_count = clear_voice_prompt_cache()
+        return {
+            "message": "Voice prompt cache cleared successfully",
+            "files_deleted": deleted_count,
+        }
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=f"Failed to clear cache: {str(e)}")
+
+
+@router.get("/tasks/active", response_model=models.ActiveTasksResponse)
+async def get_active_tasks():
+    """Return all currently active downloads and generations."""
+    task_manager = get_task_manager()
+    progress_manager = get_progress_manager()
+
+    active_downloads = []
+    task_manager_downloads = task_manager.get_active_downloads()
+    progress_active = progress_manager.get_all_active()
+
+    download_map = {task.model_name: task for task in task_manager_downloads}
+    progress_map = {p["model_name"]: p for p in progress_active}
+
+    all_model_names = set(download_map.keys()) | set(progress_map.keys())
+    for model_name in all_model_names:
+        task = download_map.get(model_name)
+        progress = progress_map.get(model_name)
+
+        if task:
+            error = task.error
+            if not error:
+                with progress_manager._lock:
+                    pm_data = progress_manager._progress.get(model_name)
+                    if pm_data:
+                        error = pm_data.get("error")
+            prog = progress or {}
+            if not prog:
+                with progress_manager._lock:
+                    pm_data = progress_manager._progress.get(model_name)
+                    if pm_data:
+                        prog = pm_data
+            active_downloads.append(
+                models.ActiveDownloadTask(
+                    model_name=model_name,
+                    status=task.status,
+                    started_at=task.started_at,
+                    error=error,
+                    progress=prog.get("progress"),
+                    current=prog.get("current"),
+                    total=prog.get("total"),
+                    filename=prog.get("filename"),
+                )
+            )
+        elif progress:
+            timestamp_str = progress.get("timestamp")
+            if timestamp_str:
+                try:
+                    started_at = datetime.fromisoformat(timestamp_str.replace("Z", "+00:00"))
+                except (ValueError, AttributeError):
+                    started_at = datetime.utcnow()
+            else:
+                started_at = datetime.utcnow()
+
+            active_downloads.append(
+                models.ActiveDownloadTask(
+                    model_name=model_name,
+                    status=progress.get("status", "downloading"),
+                    started_at=started_at,
+                    error=progress.get("error"),
+                    progress=progress.get("progress"),
+                    current=progress.get("current"),
+                    total=progress.get("total"),
+                    filename=progress.get("filename"),
+                )
+            )
+
+    active_generations = []
+    for gen_task in task_manager.get_active_generations():
+        active_generations.append(
+            models.ActiveGenerationTask(
+                task_id=gen_task.task_id,
+                profile_id=gen_task.profile_id,
+                text_preview=gen_task.text_preview,
+                started_at=gen_task.started_at,
+            )
+        )
+
+    return models.ActiveTasksResponse(
+        downloads=active_downloads,
+        generations=active_generations,
+    )

backend/routes/transcription.py

@@ -0,0 +1,84 @@
+"""Transcription endpoints."""
+
+import asyncio
+import tempfile
+from pathlib import Path
+
+from fastapi import APIRouter, File, Form, HTTPException, UploadFile
+
+from .. import models
+from ..services import transcribe
+from ..services.task_queue import create_background_task
+from ..utils.tasks import get_task_manager
+
+router = APIRouter()
+
+UPLOAD_CHUNK_SIZE = 1024 * 1024  # 1MB
+
+
+@router.post("/transcribe", response_model=models.TranscriptionResponse)
+async def transcribe_audio(
+    file: UploadFile = File(...),
+    language: str | None = Form(None),
+    model: str | None = Form(None),
+):
+    """Transcribe audio file to text."""
+    with tempfile.NamedTemporaryFile(suffix=".wav", delete=False) as tmp:
+        while chunk := await file.read(UPLOAD_CHUNK_SIZE):
+            tmp.write(chunk)
+        tmp_path = tmp.name
+
+    try:
+        from ..utils.audio import load_audio
+        from ..backends import WHISPER_HF_REPOS
+
+        audio, sr = await asyncio.to_thread(load_audio, tmp_path)
+        duration = len(audio) / sr
+
+        whisper_model = transcribe.get_whisper_model()
+        model_size = model if model else whisper_model.model_size
+
+        valid_sizes = list(WHISPER_HF_REPOS.keys())
+        if model_size not in valid_sizes:
+            raise HTTPException(
+                status_code=400,
+                detail=f"Invalid model size '{model_size}'. Must be one of: {', '.join(valid_sizes)}",
+            )
+
+        already_loaded = whisper_model.is_loaded() and whisper_model.model_size == model_size
+        if not already_loaded and not whisper_model._is_model_cached(model_size):
+            progress_model_name = f"whisper-{model_size}"
+            task_manager = get_task_manager()
+
+            async def download_whisper_background():
+                try:
+                    await whisper_model.load_model_async(model_size)
+                    task_manager.complete_download(progress_model_name)
+                except Exception as e:
+                    task_manager.error_download(progress_model_name, str(e))
+
+            task_manager.start_download(progress_model_name)
+            create_background_task(download_whisper_background())
+
+            raise HTTPException(
+                status_code=202,
+                detail={
+                    "message": f"Whisper model {model_size} is being downloaded. Please wait and try again.",
+                    "model_name": progress_model_name,
+                    "downloading": True,
+                },
+            )
+
+        text = await whisper_model.transcribe(tmp_path, language, model_size)
+
+        return models.TranscriptionResponse(
+            text=text,
+            duration=duration,
+        )
+
+    except HTTPException:
+        raise
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+    finally:
+        Path(tmp_path).unlink(missing_ok=True)

backend/server.py

@@ -6,6 +6,39 @@ absolute imports instead of relative imports.
 """
 
 import sys
+import os
+
+# On Windows with --noconsole (PyInstaller), sys.stdout/stderr are None.
+# They can also be broken file objects in some edge cases.
+# Redirect to devnull to prevent crashes from print()/tqdm/logging.
+def _is_writable(stream):
+    """Check if a stream is usable for writing."""
+    if stream is None:
+        return False
+    try:
+        stream.write("")
+        return True
+    except Exception:
+        return False
+
+if not _is_writable(sys.stdout):
+    sys.stdout = open(os.devnull, 'w')
+if not _is_writable(sys.stderr):
+    sys.stderr = open(os.devnull, 'w')
+
+# PyInstaller + multiprocessing: child processes re-execute the frozen binary
+# with internal arguments. freeze_support() handles this and exits early.
+import multiprocessing
+multiprocessing.freeze_support()
+
+# In frozen builds, piper_phonemize's espeak-ng C library falls back to
+# /usr/share/espeak-ng-data/ which doesn't exist.  Point it at the bundled
+# data directory instead.
+if getattr(sys, 'frozen', False):
+    _meipass = getattr(sys, '_MEIPASS', os.path.dirname(sys.executable))
+    _espeak_data = os.path.join(_meipass, 'piper_phonemize', 'espeak-ng-data')
+    if os.path.isdir(_espeak_data):
+        os.environ.setdefault('ESPEAK_DATA_PATH', _espeak_data)
 
 # Fast path: handle --version before any heavy imports so the Rust
 # version check doesn't block for 30+ seconds loading torch etc.

backend/services/__init__.py

@@ -0,0 +1 @@
+# Services layer — generation orchestration and background task management.

backend/services/channels.py

@@ -7,14 +7,14 @@ from datetime import datetime
 import uuid
 from sqlalchemy.orm import Session
 
-from .models import (
+from ..models import (
     AudioChannelCreate,
     AudioChannelUpdate,
     AudioChannelResponse,
     ChannelVoiceAssignment,
     ProfileChannelAssignment,
 )
-from .database import (
+from ..database import (
     AudioChannel as DBAudioChannel,
     ChannelDeviceMapping as DBChannelDeviceMapping,
     ProfileChannelMapping as DBProfileChannelMapping,

backend/services/cuda.py

@@ -14,9 +14,9 @@ import sys
 from pathlib import Path
 from typing import Optional
 
-from .config import get_data_dir
+from ..config import get_data_dir
-from .utils.progress import get_progress_manager
+from ..utils.progress import get_progress_manager
-from . import __version__
+from .. import __version__
 
 logger = logging.getLogger(__name__)
 

backend/services/effects.py

@@ -11,8 +11,8 @@ from typing import List, Optional
 from sqlalchemy.orm import Session
 from sqlalchemy.exc import IntegrityError
 
-from .database import EffectPreset as DBEffectPreset
+from ..database import EffectPreset as DBEffectPreset
-from .models import EffectPresetResponse, EffectPresetCreate, EffectPresetUpdate, EffectConfig
+from ..models import EffectPresetResponse, EffectPresetCreate, EffectPresetUpdate, EffectConfig
 
 
 def _preset_response(p: DBEffectPreset) -> EffectPresetResponse:

backend/services/export_import.py

@@ -12,16 +12,11 @@ from pathlib import Path
 from typing import Optional
 from sqlalchemy.orm import Session
 
-from .models import VoiceProfileResponse
+from ..models import VoiceProfileResponse
-from .database import VoiceProfile as DBVoiceProfile, ProfileSample as DBProfileSample, Generation as DBGeneration, GenerationVersion as DBGenerationVersion
+from ..database import VoiceProfile as DBVoiceProfile, ProfileSample as DBProfileSample, Generation as DBGeneration, GenerationVersion as DBGenerationVersion
 from .profiles import create_profile, add_profile_sample
-from .models import VoiceProfileCreate
+from ..models import VoiceProfileCreate
-from . import config
+from .. import config
-
-
-def _get_profiles_dir() -> Path:
-    """Get profiles directory from config."""
-    return config.get_profiles_dir()
 
 
 def _get_unique_profile_name(name: str, db: Session) -> str:
@@ -99,7 +94,7 @@ def export_profile_to_zip(profile_id: str, db: Session) -> bytes:
 
         # Create samples.json mapping
         samples_data = {}
-        profile_dir = _get_profiles_dir() / profile_id
+        profile_dir = config.get_profiles_dir() / profile_id
 
         for sample in samples:
             # Get filename from audio_path (should be {sample_id}.wav)
@@ -181,7 +176,7 @@ async def import_profile_from_zip(file_bytes: bytes, db: Session) -> VoiceProfil
             profile = await create_profile(profile_create, db)
 
             # Extract and add samples
-            profile_dir = _get_profiles_dir() / profile.id
+            profile_dir = config.get_profiles_dir() / profile.id
             profile_dir.mkdir(parents=True, exist_ok=True)
 
             # Handle avatar if present
@@ -351,7 +346,7 @@ async def import_generation_from_zip(file_bytes: bytes, db: Session) -> dict:
     import tempfile
     import shutil
     from datetime import datetime
-    from . import config
+    from .. import config
     
     zip_buffer = io.BytesIO(file_bytes)
     

backend/services/generation.py

@@ -0,0 +1,253 @@
+"""
+Unified TTS generation orchestration.
+
+Replaces the three near-identical closures (_run_generation, _run_retry,
+_run_regenerate) that lived in main.py with a single ``run_generation()``
+function parameterized by *mode*.
+
+Mode differences:
+  - "generate"   : full pipeline -- save clean version, optionally apply
+                    effects and create a processed version.
+  - "retry"      : re-runs a failed generation with the same seed.
+                    No effects, no version creation.
+  - "regenerate" : re-runs with seed=None for variation.  Creates a new
+                    version with an auto-incremented "take-N" label.
+"""
+
+from __future__ import annotations
+
+import traceback
+from typing import Literal, Optional
+
+from .. import config
+from . import history, profiles
+from ..database import get_db
+from ..utils.tasks import get_task_manager
+
+
+async def run_generation(
+    *,
+    generation_id: str,
+    profile_id: str,
+    text: str,
+    language: str,
+    engine: str,
+    model_size: str,
+    seed: Optional[int],
+    normalize: bool = False,
+    effects_chain: Optional[list] = None,
+    instruct: Optional[str] = None,
+    mode: Literal["generate", "retry", "regenerate"],
+    max_chunk_chars: Optional[int] = None,
+    crossfade_ms: Optional[int] = None,
+    version_id: Optional[str] = None,
+) -> None:
+    """Execute TTS inference and persist the result.
+
+    This is the single entry point for all background generation work.
+    It is designed to be enqueued via ``services.task_queue.enqueue_generation``.
+    """
+    from ..backends import load_engine_model, get_tts_backend_for_engine, engine_needs_trim
+    from ..utils.chunked_tts import generate_chunked
+    from ..utils.audio import normalize_audio, save_audio, trim_tts_output
+
+    task_manager = get_task_manager()
+    bg_db = next(get_db())
+
+    try:
+        tts_model = get_tts_backend_for_engine(engine)
+
+        if not tts_model.is_loaded():
+            await history.update_generation_status(generation_id, "loading_model", bg_db)
+
+        await load_engine_model(engine, model_size)
+
+        voice_prompt = await profiles.create_voice_prompt_for_profile(
+            profile_id,
+            bg_db,
+            use_cache=True,
+            engine=engine,
+        )
+
+        await history.update_generation_status(generation_id, "generating", bg_db)
+        trim_fn = trim_tts_output if engine_needs_trim(engine) else None
+
+        gen_kwargs: dict = dict(
+            language=language,
+            seed=seed if mode != "regenerate" else None,
+            instruct=instruct,
+            trim_fn=trim_fn,
+        )
+        if max_chunk_chars is not None:
+            gen_kwargs["max_chunk_chars"] = max_chunk_chars
+        if crossfade_ms is not None:
+            gen_kwargs["crossfade_ms"] = crossfade_ms
+
+        audio, sample_rate = await generate_chunked(tts_model, text, voice_prompt, **gen_kwargs)
+
+        # --- Normalize (generate and regenerate always; retry skips) -----
+        if normalize or mode == "regenerate":
+            audio = normalize_audio(audio)
+
+        duration = len(audio) / sample_rate
+
+        # --- Persist audio and update status -----------------------------
+        if mode == "generate":
+            final_path = _save_generate(
+                generation_id=generation_id,
+                audio=audio,
+                sample_rate=sample_rate,
+                effects_chain=effects_chain,
+                save_audio=save_audio,
+                db=bg_db,
+            )
+        elif mode == "retry":
+            final_path = _save_retry(
+                generation_id=generation_id,
+                audio=audio,
+                sample_rate=sample_rate,
+                save_audio=save_audio,
+            )
+        elif mode == "regenerate":
+            final_path = _save_regenerate(
+                generation_id=generation_id,
+                version_id=version_id,
+                audio=audio,
+                sample_rate=sample_rate,
+                save_audio=save_audio,
+                db=bg_db,
+            )
+
+        await history.update_generation_status(
+            generation_id=generation_id,
+            status="completed",
+            db=bg_db,
+            audio_path=final_path,
+            duration=duration,
+        )
+
+    except Exception as e:
+        traceback.print_exc()
+        await history.update_generation_status(
+            generation_id=generation_id,
+            status="failed",
+            db=bg_db,
+            error=str(e),
+        )
+    finally:
+        task_manager.complete_generation(generation_id)
+        bg_db.close()
+
+
+def _save_generate(
+    *,
+    generation_id: str,
+    audio,
+    sample_rate: int,
+    effects_chain: Optional[list],
+    save_audio,
+    db,
+) -> str:
+    """Save clean version and optionally an effects-processed version.
+
+    Returns the final audio path (processed if effects were applied,
+    otherwise clean).
+    """
+    from . import versions as versions_mod
+
+    clean_audio_path = config.get_generations_dir() / f"{generation_id}.wav"
+    save_audio(audio, str(clean_audio_path), sample_rate)
+
+    has_effects = effects_chain and any(e.get("enabled", True) for e in effects_chain)
+
+    versions_mod.create_version(
+        generation_id=generation_id,
+        label="original",
+        audio_path=str(clean_audio_path),
+        db=db,
+        effects_chain=None,
+        is_default=not has_effects,
+    )
+
+    final_audio_path = str(clean_audio_path)
+
+    if has_effects:
+        from ..utils.effects import apply_effects, validate_effects_chain
+
+        error_msg = validate_effects_chain(effects_chain)
+        if error_msg:
+            import logging
+            logging.getLogger(__name__).warning("invalid effects chain, skipping: %s", error_msg)
+            versions_mod.set_default_version(
+                versions_mod.list_versions(generation_id, db)[0].id, db
+            )
+        else:
+            processed_audio = apply_effects(audio, sample_rate, effects_chain)
+            processed_path = config.get_generations_dir() / f"{generation_id}_processed.wav"
+            save_audio(processed_audio, str(processed_path), sample_rate)
+            final_audio_path = str(processed_path)
+            versions_mod.create_version(
+                generation_id=generation_id,
+                label="version-2",
+                audio_path=str(processed_path),
+                db=db,
+                effects_chain=effects_chain,
+                is_default=True,
+            )
+
+    return final_audio_path
+
+
+def _save_retry(
+    *,
+    generation_id: str,
+    audio,
+    sample_rate: int,
+    save_audio,
+) -> str:
+    """Save retry output -- single file, no versions.
+
+    Returns the audio path.
+    """
+    audio_path = config.get_generations_dir() / f"{generation_id}.wav"
+    save_audio(audio, str(audio_path), sample_rate)
+    return str(audio_path)
+
+
+def _save_regenerate(
+    *,
+    generation_id: str,
+    version_id: Optional[str],
+    audio,
+    sample_rate: int,
+    save_audio,
+    db,
+) -> str:
+    """Save regeneration output as a new version with auto-label.
+
+    Returns the audio path.
+    """
+    from . import versions as versions_mod
+
+    import uuid as _uuid
+
+    suffix = _uuid.uuid4().hex[:8]
+    audio_path = config.get_generations_dir() / f"{generation_id}_{suffix}.wav"
+    save_audio(audio, str(audio_path), sample_rate)
+
+    # Count via DB query rather than list length to avoid TOCTOU race
+    from ..database import GenerationVersion as DBGenerationVersion
+
+    count = db.query(DBGenerationVersion).filter_by(generation_id=generation_id).count()
+    label = f"take-{count + 1}"
+
+    versions_mod.create_version(
+        generation_id=generation_id,
+        label=label,
+        audio_path=str(audio_path),
+        db=db,
+        effects_chain=None,
+        is_default=True,
+    )
+
+    return str(audio_path)

backend/services/history.py

@@ -10,14 +10,9 @@ from pathlib import Path
 from sqlalchemy.orm import Session
 from sqlalchemy import or_
 
-from .models import GenerationRequest, GenerationResponse, HistoryQuery, HistoryResponse, HistoryListResponse, GenerationVersionResponse, EffectConfig
+from ..models import GenerationRequest, GenerationResponse, HistoryQuery, HistoryResponse, HistoryListResponse, GenerationVersionResponse, EffectConfig
-from .database import Generation as DBGeneration, GenerationVersion as DBGenerationVersion, VoiceProfile as DBVoiceProfile
+from ..database import Generation as DBGeneration, GenerationVersion as DBGenerationVersion, VoiceProfile as DBVoiceProfile
-from . import config
+from .. import config
-
-
-def _get_generations_dir() -> Path:
-    """Get generations directory from config."""
-    return config.get_generations_dir()
 
 
 def _get_versions_for_generation(generation_id: str, db: Session) -> tuple:

backend/services/profiles.py

@@ -10,23 +10,23 @@ from pathlib import Path
 from sqlalchemy.orm import Session
 from sqlalchemy import func, select
 
-from .models import (
+from ..models import (
     VoiceProfileCreate,
     VoiceProfileResponse,
     ProfileSampleCreate,
     ProfileSampleResponse,
 )
-from .database import (
+from ..database import (
     VoiceProfile as DBVoiceProfile,
     ProfileSample as DBProfileSample,
     Generation as DBGeneration,
 )
-from .models import EffectConfig
+from ..models import EffectConfig
-from .utils.audio import validate_reference_audio, load_audio, save_audio
+from ..utils.audio import validate_reference_audio, validate_and_load_reference_audio, load_audio, save_audio
-from .utils.images import validate_image, process_avatar
+from ..utils.images import validate_image, process_avatar
-from .utils.cache import _get_cache_dir, clear_profile_cache
+from ..utils.cache import _get_cache_dir, clear_profile_cache
 from .tts import get_tts_model
-from . import config
+from .. import config
 import json as _json
 
 
@@ -43,6 +43,7 @@ def _profile_to_response(
             effects_chain = [EffectConfig(**e) for e in raw]
         except Exception as e:
             import logging
+
             logging.warning(f"Failed to parse effects_chain for profile {profile.id}: {e}")
     return VoiceProfileResponse(
         id=profile.id,
@@ -58,11 +59,6 @@ def _profile_to_response(
     )
 
 
-def _get_profiles_dir() -> Path:
-    """Get profiles directory from config."""
-    return config.get_profiles_dir()
-
-
 async def create_profile(
     data: VoiceProfileCreate,
     db: Session,
@@ -80,12 +76,10 @@ async def create_profile(
     Raises:
         ValueError: If a profile with the same name already exists
     """
-    # Check if profile name already exists
     existing_profile = db.query(DBVoiceProfile).filter_by(name=data.name).first()
     if existing_profile:
         raise ValueError(f"A profile with the name '{data.name}' already exists. Please choose a different name.")
 
-    # Create profile in database
     db_profile = DBVoiceProfile(
         id=str(uuid.uuid4()),
         name=data.name,
@@ -99,8 +93,7 @@ async def create_profile(
     db.commit()
     db.refresh(db_profile)
 
-    # Create profile directory
+    profile_dir = config.get_profiles_dir() / db_profile.id
-    profile_dir = _get_profiles_dir() / db_profile.id
     profile_dir.mkdir(parents=True, exist_ok=True)
 
     return _profile_to_response(db_profile)
@@ -114,56 +107,54 @@ async def add_profile_sample(
 ) -> ProfileSampleResponse:
     """
     Add a sample to a voice profile.
-    
+
     Args:
         profile_id: Profile ID
         audio_path: Path to temporary audio file
         reference_text: Transcript of audio
         db: Database session
-        
+
     Returns:
         Created sample
     """
-    # Validate profile exists
+    import asyncio
+
     profile = db.query(DBVoiceProfile).filter_by(id=profile_id).first()
     if not profile:
         raise ValueError(f"Profile {profile_id} not found")
-    
+
-    # Validate audio
+    # Validate and load audio in a single pass, off the event loop
-    is_valid, error_msg = validate_reference_audio(audio_path)
+    is_valid, error_msg, audio, sr = await asyncio.to_thread(
+        validate_and_load_reference_audio, audio_path
+    )
     if not is_valid:
         raise ValueError(f"Invalid reference audio: {error_msg}")
-    
+
-    # Create sample ID and directory
     sample_id = str(uuid.uuid4())
-    profile_dir = _get_profiles_dir() / profile_id
+    profile_dir = config.get_profiles_dir() / profile_id
     profile_dir.mkdir(parents=True, exist_ok=True)
-    
+
-    # Copy audio file to profile directory
     dest_path = profile_dir / f"{sample_id}.wav"
-    audio, sr = load_audio(audio_path)
+    await asyncio.to_thread(save_audio, audio, str(dest_path), sr)
-    save_audio(audio, str(dest_path), sr)
+
-    
-    # Create database entry
     db_sample = DBProfileSample(
         id=sample_id,
         profile_id=profile_id,
         audio_path=str(dest_path),
         reference_text=reference_text,
     )
-    
+
     db.add(db_sample)
-    
+
-    # Update profile timestamp
     profile.updated_at = datetime.utcnow()
-    
+
     db.commit()
     db.refresh(db_sample)
-    
+
     # Invalidate combined audio cache for this profile
     # Since a new sample was added, any cached combined audio is now stale
     clear_profile_cache(profile_id)
-    
+
     return ProfileSampleResponse.model_validate(db_sample)
 
 
@@ -173,18 +164,18 @@ async def get_profile(
 ) -> Optional[VoiceProfileResponse]:
     """
     Get a voice profile by ID.
-    
+
     Args:
         profile_id: Profile ID
         db: Database session
-        
+
     Returns:
         Profile or None if not found
     """
     profile = db.query(DBVoiceProfile).filter_by(id=profile_id).first()
     if not profile:
         return None
-    
+
     return _profile_to_response(profile)
 
 
@@ -194,11 +185,11 @@ async def get_profile_samples(
 ) -> List[ProfileSampleResponse]:
     """
     Get all samples for a profile.
-    
+
     Args:
         profile_id: Profile ID
         db: Database session
-        
+
     Returns:
         List of samples
     """
@@ -209,33 +200,27 @@ async def get_profile_samples(
 async def list_profiles(db: Session) -> List[VoiceProfileResponse]:
     """
     List all voice profiles with generation and sample counts.
-    
+
     Args:
         db: Database session
-        
+
     Returns:
         List of profiles
     """
-    profiles = db.query(DBVoiceProfile).order_by(
+    profiles = db.query(DBVoiceProfile).order_by(DBVoiceProfile.created_at.desc()).all()
-        DBVoiceProfile.created_at.desc()
-    ).all()
 
     if not profiles:
         return []
 
     # Batch-fetch generation counts
     gen_counts_rows = (
-        db.query(DBGeneration.profile_id, func.count(DBGeneration.id))
+        db.query(DBGeneration.profile_id, func.count(DBGeneration.id)).group_by(DBGeneration.profile_id).all()
-        .group_by(DBGeneration.profile_id)
-        .all()
     )
     gen_counts = {row[0]: row[1] for row in gen_counts_rows}
 
     # Batch-fetch sample counts
     sample_counts_rows = (
-        db.query(DBProfileSample.profile_id, func.count(DBProfileSample.id))
+        db.query(DBProfileSample.profile_id, func.count(DBProfileSample.id)).group_by(DBProfileSample.profile_id).all()
-        .group_by(DBProfileSample.profile_id)
-        .all()
     )
     sample_counts = {row[0]: row[1] for row in sample_counts_rows}
 
@@ -272,13 +257,11 @@ async def update_profile(
     if not profile:
         return None
 
-    # Check if the new name conflicts with another profile
     if profile.name != data.name:
         existing_profile = db.query(DBVoiceProfile).filter_by(name=data.name).first()
         if existing_profile:
             raise ValueError(f"A profile with the name '{data.name}' already exists. Please choose a different name.")
 
-    # Update fields
     profile.name = data.name
     profile.description = data.description
     profile.language = data.language
@@ -296,33 +279,30 @@ async def delete_profile(
 ) -> bool:
     """
     Delete a voice profile and all associated data.
-    
+
     Args:
         profile_id: Profile ID
         db: Database session
-        
+
     Returns:
         True if deleted, False if not found
     """
     profile = db.query(DBVoiceProfile).filter_by(id=profile_id).first()
     if not profile:
         return False
-    
+
-    # Delete samples from database
     db.query(DBProfileSample).filter_by(profile_id=profile_id).delete()
-    
+
-    # Delete profile from database
     db.delete(profile)
     db.commit()
-    
+
-    # Delete profile directory
+    profile_dir = config.get_profiles_dir() / profile_id
-    profile_dir = _get_profiles_dir() / profile_id
     if profile_dir.exists():
         shutil.rmtree(profile_dir)
-    
+
     # Clean up combined audio cache files for this profile
     clear_profile_cache(profile_id)
-    
+
     return True
 
 
@@ -332,34 +312,32 @@ async def delete_profile_sample(
 ) -> bool:
     """
     Delete a profile sample.
-    
+
     Args:
         sample_id: Sample ID
         db: Database session
-        
+
     Returns:
         True if deleted, False if not found
     """
     sample = db.query(DBProfileSample).filter_by(id=sample_id).first()
     if not sample:
         return False
-    
+
     # Store profile_id before deleting
     profile_id = sample.profile_id
-    
+
-    # Delete audio file
     audio_path = Path(sample.audio_path)
     if audio_path.exists():
         audio_path.unlink()
-    
+
-    # Delete from database
     db.delete(sample)
     db.commit()
-    
+
     # Invalidate combined audio cache for this profile
     # Since the sample set changed, any cached combined audio is now stale
     clear_profile_cache(profile_id)
-    
+
     return True
 
 
@@ -370,30 +348,30 @@ async def update_profile_sample(
 ) -> Optional[ProfileSampleResponse]:
     """
     Update a profile sample's reference text.
-    
+
     Args:
         sample_id: Sample ID
         reference_text: Updated reference text
         db: Database session
-        
+
     Returns:
         Updated sample or None if not found
     """
     sample = db.query(DBProfileSample).filter_by(id=sample_id).first()
     if not sample:
         return None
-    
+
     # Store profile_id before updating
     profile_id = sample.profile_id
-    
+
     sample.reference_text = reference_text
     db.commit()
     db.refresh(sample)
-    
+
     # Invalidate combined audio cache for this profile
     # Since the reference text changed, cache keys and combined text are now stale
     clear_profile_cache(profile_id)
-    
+
     return ProfileSampleResponse.model_validate(sample)
 
 
@@ -415,9 +393,8 @@ async def create_voice_prompt_for_profile(
     Returns:
         Voice prompt dictionary
     """
-    from .backends import get_tts_backend_for_engine
+    from ..backends import get_tts_backend_for_engine
 
-    # Get all samples for profile
     samples = db.query(DBProfileSample).filter_by(profile_id=profile_id).all()
 
     if not samples:
@@ -426,7 +403,6 @@ async def create_voice_prompt_for_profile(
     tts_model = get_tts_backend_for_engine(engine)
 
     if len(samples) == 1:
-        # Single sample - use directly
         sample = samples[0]
         voice_prompt, _ = await tts_model.create_voice_prompt(
             sample.audio_path,
@@ -435,11 +411,9 @@ async def create_voice_prompt_for_profile(
         )
         return voice_prompt
     else:
-        # Multiple samples - combine them
         audio_paths = [s.audio_path for s in samples]
         reference_texts = [s.reference_text for s in samples]
 
-        # Combine audio
         combined_audio, combined_text = await tts_model.combine_voice_prompts(
             audio_paths,
             reference_texts,
@@ -448,18 +422,16 @@ async def create_voice_prompt_for_profile(
         # Save combined audio to cache directory (persistent)
         # Create a hash of sample IDs to identify this specific combination
         import hashlib
+
         sample_ids_str = "-".join(sorted([s.id for s in samples]))
         combination_hash = hashlib.md5(sample_ids_str.encode()).hexdigest()[:12]
-        
+
-        # Store in cache directory
         cache_dir = _get_cache_dir()
         cache_dir.mkdir(parents=True, exist_ok=True)
         combined_path = cache_dir / f"combined_{profile_id}_{combination_hash}.wav"
-        
+
-        # Save combined audio
         save_audio(combined_audio, str(combined_path), 24000)
 
-        # Create prompt from combined audio
         voice_prompt, _ = await tts_model.create_voice_prompt(
             str(combined_path),
             combined_text,
@@ -484,17 +456,14 @@ async def upload_avatar(
     Returns:
         Updated profile
     """
-    # Validate profile exists
     profile = db.query(DBVoiceProfile).filter_by(id=profile_id).first()
     if not profile:
         raise ValueError(f"Profile {profile_id} not found")
 
-    # Validate image
     is_valid, error_msg = validate_image(image_path)
     if not is_valid:
         raise ValueError(error_msg)
 
-    # Delete existing avatar if present
     if profile.avatar_path:
         old_avatar = Path(profile.avatar_path)
         if old_avatar.exists():
@@ -502,27 +471,22 @@ async def upload_avatar(
 
     # Determine file extension from uploaded file
     from PIL import Image
+
     with Image.open(image_path) as img:
         # Normalize JPEG variants (MPO is multi-picture format from some cameras)
         img_format = img.format
-        if img_format in ('MPO', 'JPG'):
+        if img_format in ("MPO", "JPG"):
-            img_format = 'JPEG'
+            img_format = "JPEG"
-        
-        ext_map = {
-            'PNG': '.png',
-            'JPEG': '.jpg',
-            'WEBP': '.webp'
-        }
-        ext = ext_map.get(img_format, '.png')
 
-    # Save processed image to profile directory
+        ext_map = {"PNG": ".png", "JPEG": ".jpg", "WEBP": ".webp"}
-    profile_dir = _get_profiles_dir() / profile_id
+        ext = ext_map.get(img_format, ".png")
+
+    profile_dir = config.get_profiles_dir() / profile_id
     profile_dir.mkdir(parents=True, exist_ok=True)
     output_path = profile_dir / f"avatar{ext}"
 
     process_avatar(image_path, str(output_path))
 
-    # Update database
     profile.avatar_path = str(output_path)
     profile.updated_at = datetime.utcnow()
 
@@ -550,12 +514,10 @@ async def delete_avatar(
     if not profile or not profile.avatar_path:
         return False
 
-    # Delete avatar file
     avatar_path = Path(profile.avatar_path)
     if avatar_path.exists():
         avatar_path.unlink()
 
-    # Update database
     profile.avatar_path = None
     profile.updated_at = datetime.utcnow()
 

backend/services/stories.py

@@ -10,7 +10,7 @@ from pathlib import Path
 from sqlalchemy.orm import Session
 from sqlalchemy import func
 
-from .models import (
+from ..models import (
     StoryCreate,
     StoryResponse,
     StoryDetailResponse,
@@ -22,9 +22,14 @@ from .models import (
     StoryItemSplit,
     StoryItemVersionUpdate,
 )
-from .database import Story as DBStory, StoryItem as DBStoryItem, Generation as DBGeneration, VoiceProfile as DBVoiceProfile
+from ..database import (
+    Story as DBStory,
+    StoryItem as DBStoryItem,
+    Generation as DBGeneration,
+    VoiceProfile as DBVoiceProfile,
+)
 from .history import _get_versions_for_generation
-from .utils.audio import load_audio, save_audio
+from ..utils.audio import load_audio, save_audio
 import numpy as np
 
 
@@ -49,11 +54,11 @@ def _build_item_detail(
         id=item.id,
         story_id=item.story_id,
         generation_id=item.generation_id,
-        version_id=getattr(item, 'version_id', None),
+        version_id=getattr(item, "version_id", None),
         start_time_ms=item.start_time_ms,
         track=item.track,
-        trim_start_ms=getattr(item, 'trim_start_ms', 0),
+        trim_start_ms=getattr(item, "trim_start_ms", 0),
-        trim_end_ms=getattr(item, 'trim_end_ms', 0),
+        trim_end_ms=getattr(item, "trim_end_ms", 0),
         created_at=item.created_at,
         profile_id=generation.profile_id,
         profile_name=profile_name,
@@ -95,10 +100,7 @@ async def create_story(
     db.commit()
     db.refresh(db_story)
 
-    # Get item count
+    item_count = db.query(func.count(DBStoryItem.id)).filter(DBStoryItem.story_id == db_story.id).scalar()
-    item_count = db.query(func.count(DBStoryItem.id)).filter(
-        DBStoryItem.story_id == db_story.id
-    ).scalar()
 
     response = StoryResponse.model_validate(db_story)
     response.item_count = item_count
@@ -118,17 +120,15 @@ async def list_stories(
         List of stories with item counts
     """
     stories = db.query(DBStory).order_by(DBStory.updated_at.desc()).all()
-    
+
     result = []
     for story in stories:
-        item_count = db.query(func.count(DBStoryItem.id)).filter(
+        item_count = db.query(func.count(DBStoryItem.id)).filter(DBStoryItem.story_id == story.id).scalar()
-            DBStoryItem.story_id == story.id
+
-        ).scalar()
-        
         response = StoryResponse.model_validate(story)
         response.item_count = item_count
         result.append(response)
-    
+
     return result
 
 
@@ -150,22 +150,15 @@ async def get_story(
     if not story:
         return None
 
-    # Get all items ordered by start_time_ms
+    items = (
-    items = db.query(
+        db.query(DBStoryItem, DBGeneration, DBVoiceProfile.name.label("profile_name"))
-        DBStoryItem,
+        .join(DBGeneration, DBStoryItem.generation_id == DBGeneration.id)
-        DBGeneration,
+        .join(DBVoiceProfile, DBGeneration.profile_id == DBVoiceProfile.id)
-        DBVoiceProfile.name.label('profile_name')
+        .filter(DBStoryItem.story_id == story_id)
-    ).join(
+        .order_by(DBStoryItem.start_time_ms)
-        DBGeneration,
+        .all()
-        DBStoryItem.generation_id == DBGeneration.id
+    )
-    ).join(
-        DBVoiceProfile,
-        DBGeneration.profile_id == DBVoiceProfile.id
-    ).filter(
-        DBStoryItem.story_id == story_id
-    ).order_by(DBStoryItem.start_time_ms).all()
 
-    # Build item details
     item_details = []
     for item, generation, profile_name in items:
         item_details.append(_build_item_detail(item, generation, profile_name, db))
@@ -202,10 +195,7 @@ async def update_story(
     db.commit()
     db.refresh(story)
 
-    # Get item count
+    item_count = db.query(func.count(DBStoryItem.id)).filter(DBStoryItem.story_id == story.id).scalar()
-    item_count = db.query(func.count(DBStoryItem.id)).filter(
-        DBStoryItem.story_id == story.id
-    ).scalar()
 
     response = StoryResponse.model_validate(story)
     response.item_count = item_count
@@ -267,10 +257,7 @@ async def add_item_to_story(
         return None
 
     # Check if generation is already in story
-    existing = db.query(DBStoryItem).filter_by(
+    existing = db.query(DBStoryItem).filter_by(story_id=story_id, generation_id=data.generation_id).first()
-        story_id=story_id,
-        generation_id=data.generation_id
-    ).first()
     if existing:
         # Return existing item
         profile = db.query(DBVoiceProfile).filter_by(id=generation.profile_id).first()
@@ -283,18 +270,16 @@ async def add_item_to_story(
     if data.start_time_ms is not None:
         start_time_ms = data.start_time_ms
     else:
-        # Find the maximum end time on the target track only
+        existing_items = (
-        existing_items = db.query(
+            db.query(DBStoryItem, DBGeneration)
-            DBStoryItem,
+            .join(DBGeneration, DBStoryItem.generation_id == DBGeneration.id)
-            DBGeneration
+            .filter(
-        ).join(
+                DBStoryItem.story_id == story_id,
-            DBGeneration,
+                DBStoryItem.track == track,
-            DBStoryItem.generation_id == DBGeneration.id
+            )
-        ).filter(
+            .all()
-            DBStoryItem.story_id == story_id,
+        )
-            DBStoryItem.track == track,
+
-        ).all()
-        
         if not existing_items:
             start_time_ms = 0
         else:
@@ -302,7 +287,7 @@ async def add_item_to_story(
             for item, gen in existing_items:
                 item_end_ms = item.start_time_ms + int(gen.duration * 1000)
                 max_end_time_ms = max(max_end_time_ms, item_end_ms)
-            
+
             # Add 200ms gap after the last item
             start_time_ms = max_end_time_ms + 200
 
@@ -317,10 +302,10 @@ async def add_item_to_story(
     )
 
     db.add(item)
-    
+
     # Update story updated_at
     story.updated_at = datetime.utcnow()
-    
+
     db.commit()
     db.refresh(item)
 
@@ -349,10 +334,14 @@ async def move_story_item(
         Updated item detail or None if not found
     """
     # Get the item
-    item = db.query(DBStoryItem).filter_by(
+    item = (
-        id=item_id,
+        db.query(DBStoryItem)
-        story_id=story_id,
+        .filter_by(
-    ).first()
+            id=item_id,
+            story_id=story_id,
+        )
+        .first()
+    )
     if not item:
         return None
 
@@ -395,10 +384,14 @@ async def remove_item_from_story(
     Returns:
         True if removed, False if not found
     """
-    item = db.query(DBStoryItem).filter_by(
+    item = (
-        id=item_id,
+        db.query(DBStoryItem)
-        story_id=story_id,
+        .filter_by(
-    ).first()
+            id=item_id,
+            story_id=story_id,
+        )
+        .first()
+    )
     if not item:
         return False
 
@@ -433,10 +426,14 @@ async def trim_story_item(
         Updated item detail or None if not found
     """
     # Get the item
-    item = db.query(DBStoryItem).filter_by(
+    item = (
-        id=item_id,
+        db.query(DBStoryItem)
-        story_id=story_id,
+        .filter_by(
-    ).first()
+            id=item_id,
+            story_id=story_id,
+        )
+        .first()
+    )
     if not item:
         return None
 
@@ -487,10 +484,14 @@ async def split_story_item(
         List of two updated item details (original and new) or None if not found/invalid
     """
     # Get the item
-    item = db.query(DBStoryItem).filter_by(
+    item = (
-        id=item_id,
+        db.query(DBStoryItem)
-        story_id=story_id,
+        .filter_by(
-    ).first()
+            id=item_id,
+            story_id=story_id,
+        )
+        .first()
+    )
     if not item:
         return None
 
@@ -500,8 +501,8 @@ async def split_story_item(
         return None
 
     # Calculate effective duration and validate split point
-    current_trim_start = getattr(item, 'trim_start_ms', 0)
+    current_trim_start = getattr(item, "trim_start_ms", 0)
-    current_trim_end = getattr(item, 'trim_end_ms', 0)
+    current_trim_end = getattr(item, "trim_end_ms", 0)
     original_duration_ms = int(generation.duration * 1000)
     effective_duration_ms = original_duration_ms - current_trim_start - current_trim_end
 
@@ -520,7 +521,7 @@ async def split_story_item(
         id=str(uuid.uuid4()),
         story_id=story_id,
         generation_id=item.generation_id,  # Same generation, different trim
-        version_id=getattr(item, 'version_id', None),  # Preserve pinned version
+        version_id=getattr(item, "version_id", None),  # Preserve pinned version
         start_time_ms=item.start_time_ms + data.split_time_ms,
         track=item.track,
         trim_start_ms=absolute_split_ms,
@@ -566,10 +567,14 @@ async def duplicate_story_item(
         New item detail or None if not found
     """
     # Get the original item
-    original_item = db.query(DBStoryItem).filter_by(
+    original_item = (
-        id=item_id,
+        db.query(DBStoryItem)
-        story_id=story_id,
+        .filter_by(
-    ).first()
+            id=item_id,
+            story_id=story_id,
+        )
+        .first()
+    )
     if not original_item:
         return None
 
@@ -579,8 +584,8 @@ async def duplicate_story_item(
         return None
 
     # Calculate effective duration
-    current_trim_start = getattr(original_item, 'trim_start_ms', 0)
+    current_trim_start = getattr(original_item, "trim_start_ms", 0)
-    current_trim_end = getattr(original_item, 'trim_end_ms', 0)
+    current_trim_end = getattr(original_item, "trim_end_ms", 0)
     original_duration_ms = int(generation.duration * 1000)
     effective_duration_ms = original_duration_ms - current_trim_start - current_trim_end
 
@@ -589,7 +594,7 @@ async def duplicate_story_item(
         id=str(uuid.uuid4()),
         story_id=story_id,
         generation_id=original_item.generation_id,  # Same generation as original
-        version_id=getattr(original_item, 'version_id', None),  # Preserve pinned version
+        version_id=getattr(original_item, "version_id", None),  # Preserve pinned version
         start_time_ms=original_item.start_time_ms + effective_duration_ms + 200,  # 200ms gap
         track=original_item.track,
         trim_start_ms=current_trim_start,
@@ -673,19 +678,13 @@ async def reorder_story_items(
         return None
 
     # Get all items for this story with their generation data
-    items_with_gen = db.query(
+    items_with_gen = (
-        DBStoryItem,
+        db.query(DBStoryItem, DBGeneration, DBVoiceProfile.name.label("profile_name"))
-        DBGeneration,
+        .join(DBGeneration, DBStoryItem.generation_id == DBGeneration.id)
-        DBVoiceProfile.name.label('profile_name')
+        .join(DBVoiceProfile, DBGeneration.profile_id == DBVoiceProfile.id)
-    ).join(
+        .filter(DBStoryItem.story_id == story_id)
-        DBGeneration,
+        .all()
-        DBStoryItem.generation_id == DBGeneration.id
+    )
-    ).join(
-        DBVoiceProfile,
-        DBGeneration.profile_id == DBVoiceProfile.id
-    ).filter(
-        DBStoryItem.story_id == story_id
-    ).all()
 
     # Create maps for quick lookup
     item_map = {item.generation_id: (item, gen, profile_name) for item, gen, profile_name in items_with_gen}
@@ -700,13 +699,13 @@ async def reorder_story_items(
 
     for gen_id in generation_ids:
         item, generation, profile_name = item_map[gen_id]
-        
+
         # Update the item's start time
         item.start_time_ms = current_time_ms
-        
+
         # Calculate the duration in ms
         duration_ms = int(generation.duration * 1000)
-        
+
         # Move to next position (current end + gap)
         current_time_ms += duration_ms + gap_ms
 
@@ -738,10 +737,14 @@ async def set_story_item_version(
     Returns:
         Updated item detail or None if not found
     """
-    item = db.query(DBStoryItem).filter_by(
+    item = (
-        id=item_id,
+        db.query(DBStoryItem)
-        story_id=story_id,
+        .filter_by(
-    ).first()
+            id=item_id,
+            story_id=story_id,
+        )
+        .first()
+    )
     if not item:
         return None
 
@@ -751,11 +754,16 @@ async def set_story_item_version(
 
     # Validate version_id belongs to this generation if provided
     if data.version_id:
-        from .database import GenerationVersion as DBGenerationVersion
+        from ..database import GenerationVersion as DBGenerationVersion
-        version = db.query(DBGenerationVersion).filter_by(
+
-            id=data.version_id,
+        version = (
-            generation_id=item.generation_id,
+            db.query(DBGenerationVersion)
-        ).first()
+            .filter_by(
+                id=data.version_id,
+                generation_id=item.generation_id,
+            )
+            .first()
+        )
         if not version:
             return None
 
@@ -793,15 +801,13 @@ async def export_story_audio(
         return None
 
     # Get all items ordered by start_time_ms
-    items = db.query(
+    items = (
-        DBStoryItem,
+        db.query(DBStoryItem, DBGeneration)
-        DBGeneration
+        .join(DBGeneration, DBStoryItem.generation_id == DBGeneration.id)
-    ).join(
+        .filter(DBStoryItem.story_id == story_id)
-        DBGeneration,
+        .order_by(DBStoryItem.start_time_ms)
-        DBStoryItem.generation_id == DBGeneration.id
+        .all()
-    ).filter(
+    )
-        DBStoryItem.story_id == story_id
-    ).order_by(DBStoryItem.start_time_ms).all()
 
     if not items:
         return None
@@ -813,8 +819,9 @@ async def export_story_audio(
     for item, generation in items:
         # Resolve audio path: use pinned version if set, otherwise generation default
         resolved_audio_path = generation.audio_path
-        if getattr(item, 'version_id', None):
+        if getattr(item, "version_id", None):
-            from .database import GenerationVersion as DBGenerationVersion
+            from ..database import GenerationVersion as DBGenerationVersion
+
             version = db.query(DBGenerationVersion).filter_by(id=item.version_id).first()
             if version:
                 resolved_audio_path = version.audio_path
@@ -826,33 +833,37 @@ async def export_story_audio(
         try:
             audio, sr = load_audio(str(audio_path), sample_rate=sample_rate)
             sample_rate = sr  # Use actual sample rate from first file
-            
+
             # Get trim values
-            trim_start_ms = getattr(item, 'trim_start_ms', 0)
+            trim_start_ms = getattr(item, "trim_start_ms", 0)
-            trim_end_ms = getattr(item, 'trim_end_ms', 0)
+            trim_end_ms = getattr(item, "trim_end_ms", 0)
-            
+
             # Calculate effective duration
             original_duration_ms = int(generation.duration * 1000)
             effective_duration_ms = original_duration_ms - trim_start_ms - trim_end_ms
-            
+
             # Slice audio based on trim values
             trim_start_sample = int((trim_start_ms / 1000.0) * sample_rate)
             trim_end_sample = int((trim_end_ms / 1000.0) * sample_rate)
-            
+
             # Extract the trimmed portion
             if trim_end_ms > 0:
-                trimmed_audio = audio[trim_start_sample:-trim_end_sample] if trim_end_sample > 0 else audio[trim_start_sample:]
+                trimmed_audio = (
+                    audio[trim_start_sample:-trim_end_sample] if trim_end_sample > 0 else audio[trim_start_sample:]
+                )
             else:
                 trimmed_audio = audio[trim_start_sample:]
-            
+
             # Store audio with its timecode info
             start_time_ms = item.start_time_ms
-            
+
-            audio_data.append({
+            audio_data.append(
-                'audio': trimmed_audio,
+                {
-                'start_time_ms': start_time_ms,
+                    "audio": trimmed_audio,
-                'duration_ms': effective_duration_ms,
+                    "start_time_ms": start_time_ms,
-            })
+                    "duration_ms": effective_duration_ms,
+                }
+            )
         except Exception:
             # Skip files that can't be loaded
             continue
@@ -861,33 +872,30 @@ async def export_story_audio(
         return None
 
     # Calculate total duration: max(start_time_ms + duration_ms)
-    max_end_time_ms = max(
+    max_end_time_ms = max((data["start_time_ms"] + data["duration_ms"] for data in audio_data), default=0)
-        (data['start_time_ms'] + data['duration_ms'] for data in audio_data),
+
-        default=0
-    )
-    
     # Convert to samples
     total_samples = int((max_end_time_ms / 1000.0) * sample_rate)
-    
+
     # Create output buffer initialized to zeros
     final_audio = np.zeros(total_samples, dtype=np.float32)
 
     # Mix each audio segment at its timecode position
     for data in audio_data:
-        audio = data['audio']
+        audio = data["audio"]
-        start_time_ms = data['start_time_ms']
+        start_time_ms = data["start_time_ms"]
-        
+
         # Calculate start sample index
         start_sample = int((start_time_ms / 1000.0) * sample_rate)
-        
+
         # Ensure we don't exceed buffer bounds
         audio_length = len(audio)
         end_sample = min(start_sample + audio_length, total_samples)
-        
+
         if start_sample < total_samples:
             # Trim audio if it extends beyond buffer
-            audio_to_mix = audio[:end_sample - start_sample]
+            audio_to_mix = audio[: end_sample - start_sample]
-            
+
             # Mix: add audio to existing buffer (overlapping audio will sum)
             # Normalize to prevent clipping (simple approach: divide by max)
             final_audio[start_sample:end_sample] += audio_to_mix
@@ -898,14 +906,14 @@ async def export_story_audio(
         final_audio = final_audio / max_val
 
     # Save to temporary file
-    with tempfile.NamedTemporaryFile(suffix='.wav', delete=False) as tmp:
+    with tempfile.NamedTemporaryFile(suffix=".wav", delete=False) as tmp:
         tmp_path = tmp.name
 
     try:
         save_audio(final_audio, tmp_path, sample_rate)
 
         # Read file bytes
-        with open(tmp_path, 'rb') as f:
+        with open(tmp_path, "rb") as f:
             audio_bytes = f.read()
 
         return audio_bytes

backend/services/task_queue.py

@@ -0,0 +1,48 @@
+"""
+Serial generation queue — ensures only one TTS inference runs at a time
+to avoid GPU contention.
+"""
+
+import asyncio
+import traceback
+
+# Keep references to fire-and-forget background tasks to prevent GC
+_background_tasks: set = set()
+
+# Generation queue — serializes TTS inference to avoid GPU contention
+_generation_queue: asyncio.Queue = None  # type: ignore  # initialized at startup
+
+
+def create_background_task(coro) -> asyncio.Task:
+    """Create a background task and prevent it from being garbage collected."""
+    task = asyncio.create_task(coro)
+    _background_tasks.add(task)
+    task.add_done_callback(_background_tasks.discard)
+    return task
+
+
+async def _generation_worker():
+    """Worker that processes generation tasks one at a time."""
+    while True:
+        coro = await _generation_queue.get()
+        try:
+            await coro
+        except Exception:
+            traceback.print_exc()
+        finally:
+            _generation_queue.task_done()
+
+
+def enqueue_generation(coro):
+    """Add a generation coroutine to the serial queue."""
+    _generation_queue.put_nowait(coro)
+
+
+def init_queue():
+    """Initialize the generation queue and start the worker.
+
+    Must be called once during application startup (inside a running event loop).
+    """
+    global _generation_queue
+    _generation_queue = asyncio.Queue()
+    create_background_task(_generation_worker())

backend/services/transcribe.py

@@ -3,7 +3,7 @@ STT (Speech-to-Text) module - delegates to backend abstraction layer.
 """
 
 from typing import Optional
-from .backends import get_stt_backend, STTBackend
+from ..backends import get_stt_backend, STTBackend
 
 
 def get_whisper_model() -> STTBackend:

backend/services/tts.py

@@ -7,7 +7,7 @@ import numpy as np
 import io
 import soundfile as sf
 
-from .backends import get_tts_backend, TTSBackend
+from ..backends import get_tts_backend, TTSBackend
 
 
 def get_tts_model() -> TTSBackend:

backend/services/versions.py

@@ -14,12 +14,12 @@ from typing import List, Optional
 
 from sqlalchemy.orm import Session
 
-from .database import (
+from ..database import (
     GenerationVersion as DBGenerationVersion,
     Generation as DBGeneration,
 )
-from .models import GenerationVersionResponse, EffectConfig
+from ..models import GenerationVersionResponse, EffectConfig
-from . import config
+from .. import config
 
 
 def _version_response(v: DBGenerationVersion) -> GenerationVersionResponse:

backend/studio.py

@@ -1,66 +0,0 @@
-"""
-Audio studio module for timeline editing.
-"""
-
-from typing import List, Dict, Optional
-import numpy as np
-
-
-class AudioStudio:
-    """Audio editing and timeline management."""
-    
-    async def get_word_timestamps(
-        self,
-        audio_path: str,
-        text: str,
-    ) -> List[Dict[str, float]]:
-        """
-        Get word-level timestamps for audio.
-        
-        Args:
-            audio_path: Path to audio file
-            text: Corresponding text
-            
-        Returns:
-            List of word timestamps: [{"word": "...", "start": 0.0, "end": 0.5}, ...]
-        """
-        # TODO: Implement Whisper alignment
-        raise NotImplementedError("Word timestamps not yet implemented")
-    
-    async def mix_audio(
-        self,
-        audio_paths: List[str],
-        volumes: Optional[List[float]] = None,
-    ) -> bytes:
-        """
-        Mix multiple audio files together.
-        
-        Args:
-            audio_paths: List of audio file paths
-            volumes: Optional volume levels (0.0-1.0) for each track
-            
-        Returns:
-            Mixed audio bytes (WAV format)
-        """
-        # TODO: Implement audio mixing
-        raise NotImplementedError("Audio mixing not yet implemented")
-    
-    async def trim_audio(
-        self,
-        audio_path: str,
-        start: float,
-        end: float,
-    ) -> bytes:
-        """
-        Trim audio to specified time range.
-        
-        Args:
-            audio_path: Path to audio file
-            start: Start time in seconds
-            end: End time in seconds
-            
-        Returns:
-            Trimmed audio bytes (WAV format)
-        """
-        # TODO: Implement audio trimming
-        raise NotImplementedError("Audio trimming not yet implemented")

backend/tests/test_generation_download.py

@@ -37,11 +37,10 @@ async def monitor_sse_stream(model_name: str, timeout: int = 120):
                     if line.startswith("data: "):
                         try:
                             data = json.loads(line[6:])
-                            print(f"[{timestamp}] → SSE Event: {data['status']:12} {data.get('progress', 0):6.1f}% {data.get('filename', '')}")
+                            print(
-                            events.append({
+                                f"[{timestamp}] → SSE Event: {data['status']:12} {data.get('progress', 0):6.1f}% {data.get('filename', '')}"
-                                **data,
+                            )
-                                "_timestamp": timestamp
+                            events.append({**data, "_timestamp": timestamp})
-                            })
 
                             # Stop if complete or error
                             if data.get("status") in ("complete", "error"):
@@ -74,12 +73,15 @@ async def trigger_generation(profile_id: str, text: str, model_size: str = "1.7B
 
     try:
         async with httpx.AsyncClient(timeout=120) as client:
-            response = await client.post(url, json={
+            response = await client.post(
-                "profile_id": profile_id,
+                url,
-                "text": text,
+                json={
-                "language": "en",
+                    "profile_id": profile_id,
-                "model_size": model_size,
+                    "text": text,
-            })
+                    "language": "en",
+                    "model_size": model_size,
+                },
+            )
 
             print(f"[{_timestamp()}] Response: {response.status_code}")
 
@@ -140,7 +142,7 @@ def _timestamp():
 async def test_generation_with_cached_model():
     """
     Test Case 1: Generation when model is already cached.
-    
+
     This should NOT show any download progress events.
     If it does, that's the UX bug we're trying to fix.
     """
@@ -194,7 +196,7 @@ async def test_generation_with_cached_model():
 async def test_generation_with_fresh_download():
     """
     Test Case 2: Generation when model needs to be downloaded.
-    
+
     This SHOULD show download progress events.
     """
     print("\n" + "=" * 80)
@@ -292,24 +294,6 @@ async def main():
         print("  Users see progress events even when the model is already cached,")
         print("  making them think the model is downloading again.")
 
-    # Test Case 2: Fresh download (optional, commented out by default)
-    # Uncomment if you want to test download progress
-    # print("\n" + "🧪 " * 20)
-    # events_download = await test_generation_with_fresh_download()
-    #
-    # print("\n" + "=" * 80)
-    # print("TEST CASE 2 RESULTS: Generation with Model Download")
-    # print("=" * 80)
-    #
-    # if not events_download:
-    #     print("ℹ Model was already cached, no download occurred")
-    # else:
-    #     print(f"✓ Received {len(events_download)} download progress events")
-    #     print("\nDownload Timeline:")
-    #     for i, event in enumerate(events_download, 1):
-    #         timestamp = event.pop("_timestamp", "??:??:??.???")
-    #         print(f"  {i}. [{timestamp}] {event}")
-
     print("\n" + "=" * 80)
     print("Test Complete!")
     print("=" * 80)

backend/tests/test_profile_duplicate_names.py

@@ -45,8 +45,8 @@ def test_db():
 @pytest.fixture
 def mock_profiles_dir(monkeypatch, tmp_path):
     """Mock the profiles directory to use a temporary path."""
-    import profiles
+    from backend import config
-    monkeypatch.setattr(profiles, '_get_profiles_dir', lambda: tmp_path)
+    monkeypatch.setattr(config, 'get_profiles_dir', lambda: tmp_path)
     return tmp_path
 
 

backend/utils/audio.py

@@ -217,22 +217,40 @@ def validate_reference_audio(
     Returns:
         Tuple of (is_valid, error_message)
     """
+    result = validate_and_load_reference_audio(
+        audio_path, min_duration, max_duration, min_rms
+    )
+    return (result[0], result[1])
+
+
+def validate_and_load_reference_audio(
+    audio_path: str,
+    min_duration: float = 2.0,
+    max_duration: float = 30.0,
+    min_rms: float = 0.01,
+) -> Tuple[bool, Optional[str], Optional[np.ndarray], Optional[int]]:
+    """
+    Validate and load reference audio in a single pass.
+    
+    Returns:
+        Tuple of (is_valid, error_message, audio_array, sample_rate)
+    """
     try:
         audio, sr = load_audio(audio_path)
         duration = len(audio) / sr
         
         if duration < min_duration:
-            return False, f"Audio too short (minimum {min_duration} seconds)"
+            return False, f"Audio too short (minimum {min_duration} seconds)", None, None
         if duration > max_duration:
-            return False, f"Audio too long (maximum {max_duration} seconds)"
+            return False, f"Audio too long (maximum {max_duration} seconds)", None, None
         
         rms = np.sqrt(np.mean(audio**2))
         if rms < min_rms:
-            return False, "Audio is too quiet or silent"
+            return False, "Audio is too quiet or silent", None, None
         
         if np.abs(audio).max() > 0.99:
-            return False, "Audio is clipping (reduce input gain)"
+            return False, "Audio is clipping (reduce input gain)", None, None
         
-        return True, None
+        return True, None, audio, sr
     except Exception as e:
-        return False, f"Error validating audio: {str(e)}"
+        return False, f"Error validating audio: {str(e)}", None, None

backend/utils/cache.py

@@ -3,12 +3,15 @@ Voice prompt caching utilities.
 """
 
 import hashlib
+import logging
 import torch
 from pathlib import Path
 from typing import Optional, Union, Dict, Any
 
 from .. import config
 
+logger = logging.getLogger(__name__)
+
 
 def _get_cache_dir() -> Path:
     """Get cache directory from config."""
@@ -93,17 +96,17 @@ def cache_voice_prompt(
 def clear_voice_prompt_cache() -> int:
     """
     Clear all voice prompt caches (memory and disk).
-    
+
     Returns:
         Number of cache files deleted
     """
     # Clear memory cache
     _memory_cache.clear()
-    
+
     # Clear disk cache
     cache_dir = _get_cache_dir()
     deleted_count = 0
-    
+
     if cache_dir.exists():
         # Delete prompt cache files
         for cache_file in cache_dir.glob("*.prompt"):
@@ -111,32 +114,32 @@ def clear_voice_prompt_cache() -> int:
                 cache_file.unlink()
                 deleted_count += 1
             except Exception as e:
-                print(f"Failed to delete cache file {cache_file}: {e}")
+                logger.warning("Failed to delete cache file %s: %s", cache_file, e)
-        
+
         # Delete combined audio files
         for audio_file in cache_dir.glob("combined_*.wav"):
             try:
                 audio_file.unlink()
                 deleted_count += 1
             except Exception as e:
-                print(f"Failed to delete combined audio file {audio_file}: {e}")
+                logger.warning("Failed to delete combined audio file %s: %s", audio_file, e)
-    
+
     return deleted_count
 
 
 def clear_profile_cache(profile_id: str) -> int:
     """
     Clear cache files for a specific profile.
-    
+
     Args:
         profile_id: Profile ID
-    
+
     Returns:
         Number of cache files deleted
     """
     cache_dir = _get_cache_dir()
     deleted_count = 0
-    
+
     if cache_dir.exists():
         # Delete combined audio files for this profile
         pattern = f"combined_{profile_id}_*.wav"
@@ -145,6 +148,6 @@ def clear_profile_cache(profile_id: str) -> int:
                 audio_file.unlink()
                 deleted_count += 1
             except Exception as e:
-                print(f"Failed to delete combined audio file {audio_file}: {e}")
+                logger.warning("Failed to delete combined audio file %s: %s", audio_file, e)
-    
+
     return deleted_count

backend/utils/chunked_tts.py

@@ -58,11 +58,6 @@ _ABBREVIATIONS = frozenset(
 _PARA_TAG_RE = re.compile(r"\[[^\]]*\]")
 
 
-# ---------------------------------------------------------------------------
-# Text splitting
-# ---------------------------------------------------------------------------
-
-
 def split_text_into_chunks(text: str, max_chars: int = DEFAULT_MAX_CHUNK_CHARS) -> List[str]:
     """Split *text* at natural boundaries into chunks of at most *max_chars*.
 
@@ -174,11 +169,6 @@ def _safe_hard_cut(segment: str, max_chars: int) -> int:
     return cut
 
 
-# ---------------------------------------------------------------------------
-# Audio concatenation
-# ---------------------------------------------------------------------------
-
-
 def concatenate_audio_chunks(
     chunks: List[np.ndarray],
     sample_rate: int,
@@ -211,11 +201,6 @@ def concatenate_audio_chunks(
     return result
 
 
-# ---------------------------------------------------------------------------
-# Engine-agnostic chunked generation
-# ---------------------------------------------------------------------------
-
-
 async def generate_chunked(
     backend,
     text: str,
@@ -264,7 +249,11 @@ async def generate_chunked(
     if len(chunks) <= 1:
         # Short text — single-shot fast path
         audio, sample_rate = await backend.generate(
-            text, voice_prompt, language, seed, instruct,
+            text,
+            voice_prompt,
+            language,
+            seed,
+            instruct,
         )
         if trim_fn is not None:
             audio = trim_fn(audio, sample_rate)
@@ -273,7 +262,9 @@ async def generate_chunked(
     # Long text — chunked generation
     logger.info(
         "Splitting %d chars into %d chunks (max %d chars each)",
-        len(text), len(chunks), max_chunk_chars,
+        len(text),
+        len(chunks),
+        max_chunk_chars,
     )
     audio_chunks: List[np.ndarray] = []
     sample_rate: int | None = None
@@ -281,7 +272,9 @@ async def generate_chunked(
     for i, chunk_text in enumerate(chunks):
         logger.info(
             "Generating chunk %d/%d (%d chars)",
-            i + 1, len(chunks), len(chunk_text),
+            i + 1,
+            len(chunks),
+            len(chunk_text),
         )
         # Vary the seed per chunk to avoid correlated RNG artefacts,
         # but keep it deterministic so the same (text, seed) pair
@@ -289,7 +282,11 @@ async def generate_chunked(
         chunk_seed = (seed + i) if seed is not None else None
 
         chunk_audio, chunk_sr = await backend.generate(
-            chunk_text, voice_prompt, language, chunk_seed, instruct,
+            chunk_text,
+            voice_prompt,
+            language,
+            chunk_seed,
+            instruct,
         )
         if trim_fn is not None:
             chunk_audio = trim_fn(chunk_audio, chunk_sr)