Merge pull request 'perf/pipeline-improvements' (#1) from perf/pipeline-improvements into main

Reviewed-on: #1
2026-03-21 04:53:45 +00:00
parent d00281f0c7 09d7c2064f
commit d8ed77b786
51 changed files with 2608 additions and 285 deletions
--- a/.claude/settings.local.json
+++ b/.claude/settings.local.json
@@ -0,0 +1,21 @@
+{
+  "permissions": {
+    "allow": [
+      "Bash(git init:*)",
+      "Bash(git:*)",
+      "WebSearch",
+      "Bash(npm create:*)",
+      "Bash(cp:*)",
+      "Bash(npm install:*)",
+      "Bash(/home/jknapp/.cargo/bin/cargo test:*)",
+      "Bash(ruff:*)",
+      "Bash(npm run:*)",
+      "Bash(npx svelte-check:*)",
+      "Bash(pip install:*)",
+      "Bash(python3:*)",
+      "Bash(/home/jknapp/.cargo/bin/cargo check:*)",
+      "Bash(cargo check:*)",
+      "Bash(npm ls:*)"
+    ]
+  }
+}
--- a/.claude/worktrees/agent-a0bd87d1
+++ b/.claude/worktrees/agent-a0bd87d1
--- a/.claude/worktrees/agent-a198b5f8
+++ b/.claude/worktrees/agent-a198b5f8
--- a/.claude/worktrees/agent-ad3d6fca
+++ b/.claude/worktrees/agent-ad3d6fca
--- a/.claude/worktrees/agent-aefe2597
+++ b/.claude/worktrees/agent-aefe2597
--- a/.gitea/workflows/build.yml
+++ b/.gitea/workflows/build.yml
@@ -0,0 +1,179 @@
+name: Build & Release
+
+on:
+  push:
+    branches: [main]
+    tags: ["v*"]
+  pull_request:
+    branches: [main]
+
+env:
+  PYTHON_VERSION: "3.11"
+  NODE_VERSION: "20"
+
+jobs:
+  build-sidecar:
+    name: Build sidecar (${{ matrix.target }})
+    runs-on: ${{ matrix.runner }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - runner: ubuntu-latest
+            target: x86_64-unknown-linux-gnu
+            platform: linux
+          - runner: windows-latest
+            target: x86_64-pc-windows-msvc
+            platform: windows
+          - runner: macos-latest
+            target: aarch64-apple-darwin
+            platform: macos
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ env.PYTHON_VERSION }}
+
+      - name: Build sidecar
+        working-directory: python
+        run: python build_sidecar.py --cpu-only
+
+      - name: Upload sidecar artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: sidecar-${{ matrix.target }}
+          path: python/dist/voice-to-notes-sidecar/
+          retention-days: 7
+
+  build-tauri:
+    name: Build app (${{ matrix.target }})
+    needs: build-sidecar
+    runs-on: ${{ matrix.runner }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - runner: ubuntu-latest
+            target: x86_64-unknown-linux-gnu
+            platform: linux
+          - runner: windows-latest
+            target: x86_64-pc-windows-msvc
+            platform: windows
+          - runner: macos-latest
+            target: aarch64-apple-darwin
+            platform: macos
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ env.NODE_VERSION }}
+          # Note: 'cache: npm' requires the Gitea instance to have
+          # Actions cache configured. Remove this if caching is unavailable.
+          cache: npm
+
+      - name: Install Rust stable
+        uses: dtolnay/rust-toolchain@stable
+
+      - name: Install system dependencies (Linux)
+        if: matrix.platform == 'linux'
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y libgtk-3-dev libwebkit2gtk-4.1-dev libappindicator3-dev librsvg2-dev patchelf
+
+      - name: Download sidecar artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: sidecar-${{ matrix.target }}
+          path: src-tauri/binaries/
+
+      - name: Make sidecar executable (Unix)
+        if: matrix.platform != 'windows'
+        run: chmod +x src-tauri/binaries/voice-to-notes-sidecar-${{ matrix.target }}
+
+      - name: Install npm dependencies
+        run: npm ci
+
+      - name: Build Tauri app
+        run: npm run tauri build
+        env:
+          TAURI_SIGNING_PRIVATE_KEY: ${{ secrets.TAURI_SIGNING_PRIVATE_KEY }}
+          TAURI_CONFIG: '{"bundle":{"externalBin":["binaries/voice-to-notes-sidecar"]}}'
+
+      - name: Upload app artifacts (Linux)
+        if: matrix.platform == 'linux'
+        uses: actions/upload-artifact@v4
+        with:
+          name: app-${{ matrix.target }}
+          path: |
+            src-tauri/target/release/bundle/deb/*.deb
+            src-tauri/target/release/bundle/appimage/*.AppImage
+          retention-days: 30
+
+      - name: Upload app artifacts (Windows)
+        if: matrix.platform == 'windows'
+        uses: actions/upload-artifact@v4
+        with:
+          name: app-${{ matrix.target }}
+          path: |
+            src-tauri/target/release/bundle/msi/*.msi
+            src-tauri/target/release/bundle/nsis/*.exe
+          retention-days: 30
+
+      - name: Upload app artifacts (macOS)
+        if: matrix.platform == 'macos'
+        uses: actions/upload-artifact@v4
+        with:
+          name: app-${{ matrix.target }}
+          path: |
+            src-tauri/target/release/bundle/dmg/*.dmg
+            src-tauri/target/release/bundle/macos/*.app
+          retention-days: 30
+
+  release:
+    name: Create Release
+    needs: build-tauri
+    if: github.ref == 'refs/heads/main'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Download all app artifacts
+        uses: actions/download-artifact@v4
+        with:
+          path: artifacts/
+          pattern: app-*
+
+      - name: Generate release tag
+        id: tag
+        run: echo "tag=build-$(date +%Y%m%d-%H%M%S)" >> $GITHUB_OUTPUT
+
+      - name: Create release
+        env:
+          BUILD_TOKEN: ${{ secrets.BUILD_TOKEN }}
+          TAG: ${{ steps.tag.outputs.tag }}
+        run: |
+          # Create the release
+          RELEASE_ID=$(curl -s -X POST \
+            -H "Authorization: token ${BUILD_TOKEN}" \
+            -H "Content-Type: application/json" \
+            -d "{\"tag_name\": \"${TAG}\", \"name\": \"Voice to Notes ${TAG}\", \"body\": \"Automated build from main branch.\", \"draft\": false, \"prerelease\": true}" \
+            "${GITHUB_SERVER_URL}/api/v1/repos/${GITHUB_REPOSITORY}/releases" | jq -r '.id')
+
+          echo "Release ID: ${RELEASE_ID}"
+
+          # Upload all artifacts
+          find artifacts/ -type f \( -name "*.deb" -o -name "*.AppImage" -o -name "*.msi" -o -name "*.exe" -o -name "*.dmg" \) | while read file; do
+            filename=$(basename "$file")
+            echo "Uploading ${filename}..."
+            curl -s -X POST \
+              -H "Authorization: token ${BUILD_TOKEN}" \
+              -H "Content-Type: application/octet-stream" \
+              --data-binary "@${file}" \
+              "${GITHUB_SERVER_URL}/api/v1/repos/${GITHUB_REPOSITORY}/releases/${RELEASE_ID}/assets?name=${filename}"
+          done
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -0,0 +1,141 @@
+name: Build & Release
+
+on:
+  push:
+    branches: [main]
+    tags: ["v*"]
+  pull_request:
+    branches: [main]
+  workflow_dispatch:
+
+env:
+  PYTHON_VERSION: "3.11"
+  NODE_VERSION: "20"
+
+jobs:
+  build-sidecar:
+    name: Build sidecar (${{ matrix.target }})
+    runs-on: ${{ matrix.runner }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - runner: ubuntu-20.04
+            target: x86_64-unknown-linux-gnu
+            platform: linux
+          - runner: windows-latest
+            target: x86_64-pc-windows-msvc
+            platform: windows
+          - runner: macos-13
+            target: x86_64-apple-darwin
+            platform: macos-intel
+          - runner: macos-14
+            target: aarch64-apple-darwin
+            platform: macos-arm
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ env.PYTHON_VERSION }}
+
+      - name: Build sidecar
+        working-directory: python
+        run: python build_sidecar.py --cpu-only
+
+      - name: Upload sidecar artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: sidecar-${{ matrix.target }}
+          path: python/dist/voice-to-notes-sidecar/
+          retention-days: 7
+
+  build-tauri:
+    name: Build app (${{ matrix.target }})
+    needs: build-sidecar
+    runs-on: ${{ matrix.runner }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - runner: ubuntu-20.04
+            target: x86_64-unknown-linux-gnu
+            platform: linux
+          - runner: windows-latest
+            target: x86_64-pc-windows-msvc
+            platform: windows
+          - runner: macos-13
+            target: x86_64-apple-darwin
+            platform: macos-intel
+          - runner: macos-14
+            target: aarch64-apple-darwin
+            platform: macos-arm
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ env.NODE_VERSION }}
+          cache: npm
+
+      - name: Install Rust stable
+        uses: dtolnay/rust-toolchain@stable
+
+      - name: Install system dependencies (Linux)
+        if: matrix.platform == 'linux'
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y libgtk-3-dev libwebkit2gtk-4.1-dev libappindicator3-dev librsvg2-dev patchelf
+
+      - name: Download sidecar artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: sidecar-${{ matrix.target }}
+          path: src-tauri/binaries/
+
+      - name: Make sidecar executable (Unix)
+        if: matrix.platform != 'windows'
+        run: chmod +x src-tauri/binaries/voice-to-notes-sidecar-${{ matrix.target }}
+
+      - name: Install npm dependencies
+        run: npm ci
+
+      - name: Build Tauri app
+        run: npm run tauri build
+        env:
+          TAURI_SIGNING_PRIVATE_KEY: ${{ secrets.TAURI_SIGNING_PRIVATE_KEY }}
+          TAURI_CONFIG: '{"bundle":{"externalBin":["binaries/voice-to-notes-sidecar"]}}'
+
+      - name: Upload app artifacts (Linux)
+        if: matrix.platform == 'linux'
+        uses: actions/upload-artifact@v4
+        with:
+          name: app-${{ matrix.target }}
+          path: |
+            src-tauri/target/release/bundle/deb/*.deb
+            src-tauri/target/release/bundle/appimage/*.AppImage
+          retention-days: 30
+
+      - name: Upload app artifacts (Windows)
+        if: matrix.platform == 'windows'
+        uses: actions/upload-artifact@v4
+        with:
+          name: app-${{ matrix.target }}
+          path: |
+            src-tauri/target/release/bundle/msi/*.msi
+            src-tauri/target/release/bundle/nsis/*.exe
+          retention-days: 30
+
+      - name: Upload app artifacts (macOS)
+        if: startsWith(matrix.platform, 'macos')
+        uses: actions/upload-artifact@v4
+        with:
+          name: app-${{ matrix.target }}
+          path: |
+            src-tauri/target/release/bundle/dmg/*.dmg
+            src-tauri/target/release/bundle/macos/*.app
+          retention-days: 30
--- a/.gitignore
+++ b/.gitignore
@@ -46,3 +46,9 @@ Thumbs.db
 *.ogg
 *.flac
 !test/fixtures/*
+
+# Sidecar build artifacts
+src-tauri/binaries/*
+!src-tauri/binaries/.gitkeep
+python/dist/
+python/build/
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -8,7 +8,7 @@ Desktop app for transcribing audio/video with speaker identification. Runs local
 - **ML pipeline:** Python sidecar process (faster-whisper, pyannote.audio, wav2vec2)
 - **Database:** SQLite (via rusqlite in Rust)
 - **Local AI:** Bundled llama-server (llama.cpp) — default, no install needed
- **Cloud AI providers:** LiteLLM, OpenAI, Anthropic (optional, user-configured)
+- **Cloud AI providers:** OpenAI, Anthropic, OpenAI-compatible endpoints (optional, user-configured)
 - **Caption export:** pysubs2 (Python)
 - **Audio UI:** wavesurfer.js
 - **Transcript editor:** TipTap (ProseMirror)
@@ -40,7 +40,13 @@ docs/                   # Architecture and design documents
 - Database: UUIDs as primary keys (TEXT type in SQLite)
 - All timestamps in milliseconds (integer) relative to media file start

+## Distribution
+- Python sidecar is frozen via PyInstaller into a standalone binary for distribution
+- Tauri bundles the sidecar via `externalBin` — no Python required for end users
+- CI/CD builds on Gitea Actions (Linux, Windows, macOS ARM)
+- Dev mode uses system Python (`VOICE_TO_NOTES_DEV=1` or debug builds)
+
 ## Platform Targets
- Linux (primary development target)
- Windows (must work, tested before release)
- macOS (future, not yet targeted)
+- Linux x86_64 (primary development target)
+- Windows x86_64
+- macOS aarch64 (Apple Silicon)
--- a/README.md
+++ b/README.md
@@ -2,28 +2,90 @@

 A desktop application that transcribes audio/video recordings with speaker identification, producing editable transcriptions with synchronized audio playback.

-## Goals
+## Features

- **Speech-to-Text Transcription** — Accurately convert spoken audio from recordings into text
- **Speaker Identification (Diarization)** — Detect and distinguish between different speakers in a conversation
- **Speaker Naming** — Assign and persist speaker names/IDs across the transcription
- **Synchronized Playback** — Click any transcribed text segment to play back the corresponding audio for review and correction
- **Export Formats**
-  - Closed captioning files (SRT, VTT) for video
-  - Plain text documents with speaker labels
- **AI Integration** — Connect to AI providers to ask questions about the conversation and generate condensed notes/summaries
+- **Speech-to-Text Transcription** — Accurate transcription via faster-whisper (Whisper models) with word-level timestamps
+- **Speaker Identification (Diarization)** — Detect and distinguish between speakers using pyannote.audio
+- **Synchronized Playback** — Click any word to seek to that point in the audio (Web Audio API for instant playback)
+- **AI Integration** — Ask questions about your transcript via OpenAI, Anthropic, or any OpenAI-compatible API (LiteLLM proxies, Ollama, vLLM)
+- **Export Formats** — SRT, WebVTT, ASS captions, plain text, and Markdown with speaker labels
+- **Cross-Platform** — Builds for Linux, Windows, and macOS (Apple Silicon)

 ## Platform Support

-| Platform | Status |
-|----------|--------|
-| Linux    | Planned (initial target) |
-| Windows  | Planned (initial target) |
-| macOS    | Future (pending hardware) |
+| Platform | Architecture | Status |
+|----------|-------------|--------|
+| Linux    | x86_64      | Supported |
+| Windows  | x86_64      | Supported |
+| macOS    | ARM (Apple Silicon) | Supported |

-## Project Status
+## Tech Stack

-**Early planning phase** — Architecture and technology decisions in progress.
+- **Desktop shell:** Tauri v2 (Rust backend + Svelte 5 / TypeScript frontend)
+- **ML pipeline:** Python sidecar (faster-whisper, pyannote.audio) — frozen via PyInstaller for distribution
+- **Audio playback:** wavesurfer.js with Web Audio API backend
+- **AI providers:** OpenAI, Anthropic, OpenAI-compatible endpoints (local or remote)
+- **Local AI:** Bundled llama-server (llama.cpp)
+- **Caption export:** pysubs2
+
+## Development
+
+### Prerequisites
+
+- Node.js 20+
+- Rust (stable)
+- Python 3.11+ with ML dependencies
+- System: `libgtk-3-dev`, `libwebkit2gtk-4.1-dev` (Linux)
+
+### Getting Started
+
+```bash
+# Install frontend dependencies
+npm install
+
+# Install Python sidecar dependencies
+cd python && pip install -e . && cd ..
+
+# Run in dev mode (uses system Python for the sidecar)
+npm run tauri:dev
+```
+
+### Building for Distribution
+
+```bash
+# Build the frozen Python sidecar
+npm run sidecar:build
+
+# Build the Tauri app (requires sidecar in src-tauri/binaries/)
+npm run tauri build
+```
+
+### CI/CD
+
+Gitea Actions workflows are in `.gitea/workflows/`. The build pipeline:
+
+1. **Build sidecar** — PyInstaller-frozen Python binary per platform (CPU-only PyTorch)
+2. **Build Tauri app** — Bundles the sidecar via `externalBin`, produces .deb/.AppImage (Linux), .msi (Windows), .dmg (macOS)
+
+#### Required Secrets
+
+| Secret | Purpose | Required? |
+|--------|---------|-----------|
+| `TAURI_SIGNING_PRIVATE_KEY` | Signs Tauri update bundles | Optional (for auto-updates) |
+
+No other secrets are needed for building. AI provider API keys and HuggingFace tokens are configured by end users in the app's Settings.
+
+### Project Structure
+
+```
+src/                    # Svelte 5 frontend
+src-tauri/              # Rust backend (Tauri commands, sidecar manager, SQLite)
+python/                 # Python sidecar (transcription, diarization, AI)
+  voice_to_notes/       # Python package
+  build_sidecar.py      # PyInstaller build script
+  voice_to_notes.spec   # PyInstaller spec
+.gitea/workflows/       # Gitea Actions CI/CD
+```

 ## License

--- a/package.json
+++ b/package.json
@@ -11,7 +11,9 @@
    "check:watch": "svelte-kit sync && svelte-check --tsconfig ./tsconfig.json --watch",
    "lint": "eslint .",
    "test": "vitest",
-    "tauri": "tauri"
+    "tauri": "tauri",
+    "tauri:dev": "VOICE_TO_NOTES_DEV=1 tauri dev",
+    "sidecar:build": "cd python && python3 build_sidecar.py"
  },
  "license": "MIT",
  "dependencies": {
--- a/python/build_sidecar.py
+++ b/python/build_sidecar.py
@@ -0,0 +1,215 @@
+#!/usr/bin/env python3
+"""Build the Voice to Notes sidecar as a standalone binary using PyInstaller.
+
+Usage:
+    python build_sidecar.py [--cpu-only]
+
+Produces a directory `dist/voice-to-notes-sidecar/` containing the frozen
+sidecar binary and all dependencies. The main binary is renamed to include
+the Tauri target triple for externalBin resolution.
+"""
+
+from __future__ import annotations
+
+import argparse
+import os
+import platform
+import shutil
+import stat
+import subprocess
+import sys
+import urllib.request
+import zipfile
+from pathlib import Path
+
+SCRIPT_DIR = Path(__file__).resolve().parent
+DIST_DIR = SCRIPT_DIR / "dist"
+BUILD_DIR = SCRIPT_DIR / "build"
+SPEC_FILE = SCRIPT_DIR / "voice_to_notes.spec"
+
+# Static ffmpeg download URLs (GPL-licensed builds)
+FFMPEG_URLS: dict[str, str] = {
+    "linux-x86_64": "https://johnvansickle.com/ffmpeg/releases/ffmpeg-release-amd64-static.tar.xz",
+    "darwin-x86_64": "https://evermeet.cx/ffmpeg/getrelease/zip",
+    "darwin-arm64": "https://evermeet.cx/ffmpeg/getrelease/zip",
+    "win32-x86_64": "https://www.gyan.dev/ffmpeg/builds/ffmpeg-release-essentials.zip",
+}
+
+
+def get_target_triple() -> str:
+    """Determine the Tauri-compatible target triple for the current platform."""
+    machine = platform.machine().lower()
+    system = platform.system().lower()
+
+    arch_map = {
+        "x86_64": "x86_64",
+        "amd64": "x86_64",
+        "aarch64": "aarch64",
+        "arm64": "aarch64",
+    }
+    arch = arch_map.get(machine, machine)
+
+    if system == "linux":
+        return f"{arch}-unknown-linux-gnu"
+    elif system == "darwin":
+        return f"{arch}-apple-darwin"
+    elif system == "windows":
+        return f"{arch}-pc-windows-msvc"
+    else:
+        return f"{arch}-unknown-{system}"
+
+
+def create_venv_and_install(cpu_only: bool) -> Path:
+    """Create a fresh venv and install dependencies."""
+    venv_dir = BUILD_DIR / "sidecar-venv"
+    if venv_dir.exists():
+        shutil.rmtree(venv_dir)
+
+    print(f"[build] Creating venv at {venv_dir}")
+    subprocess.run([sys.executable, "-m", "venv", str(venv_dir)], check=True)
+
+    # Determine pip and python paths inside venv
+    if sys.platform == "win32":
+        pip = str(venv_dir / "Scripts" / "pip")
+        python = str(venv_dir / "Scripts" / "python")
+    else:
+        pip = str(venv_dir / "bin" / "pip")
+        python = str(venv_dir / "bin" / "python")
+
+    # Upgrade pip
+    subprocess.run([pip, "install", "--upgrade", "pip"], check=True)
+
+    # Install torch (CPU-only to avoid bundling ~2GB of CUDA libs)
+    if cpu_only:
+        print("[build] Installing PyTorch (CPU-only)")
+        subprocess.run(
+            [pip, "install", "torch", "torchaudio",
+             "--index-url", "https://download.pytorch.org/whl/cpu"],
+            check=True,
+        )
+    else:
+        print("[build] Installing PyTorch (default, may include CUDA)")
+        subprocess.run([pip, "install", "torch", "torchaudio"], check=True)
+
+    # Install project and dev deps (includes pyinstaller)
+    print("[build] Installing project dependencies")
+    subprocess.run([pip, "install", "-e", f"{SCRIPT_DIR}[dev]"], check=True)
+
+    return Path(python)
+
+
+def run_pyinstaller(python: Path) -> Path:
+    """Run PyInstaller using the spec file."""
+    print("[build] Running PyInstaller")
+    subprocess.run(
+        [str(python), "-m", "PyInstaller", "--clean", "--noconfirm", str(SPEC_FILE)],
+        cwd=str(SCRIPT_DIR),
+        check=True,
+    )
+    output_dir = DIST_DIR / "voice-to-notes-sidecar"
+    if not output_dir.exists():
+        raise RuntimeError(f"PyInstaller output not found at {output_dir}")
+    return output_dir
+
+
+def download_ffmpeg(output_dir: Path) -> None:
+    """Download a static ffmpeg/ffprobe binary for the current platform."""
+    system = sys.platform
+    machine = platform.machine().lower()
+    if machine in ("amd64", "x86_64"):
+        machine = "x86_64"
+    elif machine in ("aarch64", "arm64"):
+        machine = "arm64"
+
+    key = f"{system}-{machine}"
+    if system == "win32":
+        key = f"win32-{machine}"
+    elif system == "linux":
+        key = f"linux-{machine}"
+
+    url = FFMPEG_URLS.get(key)
+    if not url:
+        print(f"[build] Warning: No ffmpeg download URL for platform {key}, skipping")
+        return
+
+    print(f"[build] Downloading ffmpeg for {key}")
+    tmp_path = output_dir / "ffmpeg_download"
+    try:
+        urllib.request.urlretrieve(url, str(tmp_path))
+
+        if url.endswith(".tar.xz"):
+            # Linux static build
+            import tarfile
+            with tarfile.open(str(tmp_path), "r:xz") as tar:
+                for member in tar.getmembers():
+                    basename = os.path.basename(member.name)
+                    if basename in ("ffmpeg", "ffprobe"):
+                        member.name = basename
+                        tar.extract(member, path=str(output_dir))
+                        dest = output_dir / basename
+                        dest.chmod(dest.stat().st_mode | stat.S_IEXEC)
+        elif url.endswith(".zip"):
+            with zipfile.ZipFile(str(tmp_path), "r") as zf:
+                for name in zf.namelist():
+                    basename = os.path.basename(name)
+                    if basename in ("ffmpeg", "ffprobe", "ffmpeg.exe", "ffprobe.exe"):
+                        data = zf.read(name)
+                        dest = output_dir / basename
+                        dest.write_bytes(data)
+                        if sys.platform != "win32":
+                            dest.chmod(dest.stat().st_mode | stat.S_IEXEC)
+        print("[build] ffmpeg downloaded successfully")
+    except Exception as e:
+        print(f"[build] Warning: Failed to download ffmpeg: {e}")
+    finally:
+        if tmp_path.exists():
+            tmp_path.unlink()
+
+
+def rename_binary(output_dir: Path, target_triple: str) -> None:
+    """Rename the main binary to include the target triple for Tauri."""
+    if sys.platform == "win32":
+        src = output_dir / "voice-to-notes-sidecar.exe"
+        dst = output_dir / f"voice-to-notes-sidecar-{target_triple}.exe"
+    else:
+        src = output_dir / "voice-to-notes-sidecar"
+        dst = output_dir / f"voice-to-notes-sidecar-{target_triple}"
+
+    if src.exists():
+        print(f"[build] Renaming {src.name} -> {dst.name}")
+        src.rename(dst)
+    else:
+        print(f"[build] Warning: Expected binary not found at {src}")
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(description="Build the Voice to Notes sidecar binary")
+    parser.add_argument(
+        "--cpu-only",
+        action="store_true",
+        default=True,
+        help="Install CPU-only PyTorch (default: True, avoids bundling CUDA)",
+    )
+    parser.add_argument(
+        "--with-cuda",
+        action="store_true",
+        help="Install PyTorch with CUDA support",
+    )
+    args = parser.parse_args()
+    cpu_only = not args.with_cuda
+
+    target_triple = get_target_triple()
+    print(f"[build] Target triple: {target_triple}")
+    print(f"[build] CPU-only: {cpu_only}")
+
+    python = create_venv_and_install(cpu_only)
+    output_dir = run_pyinstaller(python)
+    download_ffmpeg(output_dir)
+    rename_binary(output_dir, target_triple)
+
+    print(f"\n[build] Done! Sidecar built at: {output_dir}")
+    print(f"[build] Copy contents to src-tauri/binaries/ for Tauri bundling")
+
+
+if __name__ == "__main__":
+    main()
--- a/python/pyproject.toml
+++ b/python/pyproject.toml
@@ -13,6 +13,8 @@ dependencies = [
    "faster-whisper>=1.1.0",
    "pyannote.audio>=3.1.0",
    "pysubs2>=1.7.0",
+    "openai>=1.0.0",
+    "anthropic>=0.20.0",
 ]

 [project.optional-dependencies]
@@ -20,6 +22,7 @@ dev = [
    "ruff>=0.8.0",
    "pytest>=8.0.0",
    "pytest-asyncio>=0.24.0",
+    "pyinstaller>=6.0",
 ]

 [tool.ruff]
--- a/python/tests/test_diarize.py
+++ b/python/tests/test_diarize.py
@@ -1,7 +1,13 @@
 """Tests for diarization service data structures and payload conversion."""

+import time
+from unittest.mock import MagicMock, patch
+
+import pytest
+
 from voice_to_notes.services.diarize import (
    DiarizationResult,
+    DiarizeService,
    SpeakerSegment,
    diarization_to_payload,
 )
@@ -31,3 +37,74 @@ def test_diarization_to_payload_empty():
    assert payload["num_speakers"] == 0
    assert payload["speaker_segments"] == []
    assert payload["speakers"] == []
+
+
+def test_diarize_threading_progress(monkeypatch):
+    """Test that diarization emits progress while running in background thread."""
+    # Track written messages
+    written_messages = []
+    def mock_write(msg):
+        written_messages.append(msg)
+
+    # Mock pipeline that takes ~5 seconds
+    def slow_pipeline(file_path, **kwargs):
+        time.sleep(5)
+        # Return a mock diarization result (use spec=object to prevent
+        # hasattr returning True for speaker_diarization)
+        mock_result = MagicMock(spec=[])
+        mock_track = MagicMock()
+        mock_track.start = 0.0
+        mock_track.end = 5.0
+        mock_result.itertracks = MagicMock(return_value=[(mock_track, None, "SPEAKER_00")])
+        return mock_result
+
+    mock_pipeline_obj = MagicMock()
+    mock_pipeline_obj.side_effect = slow_pipeline
+
+    service = DiarizeService()
+    service._pipeline = mock_pipeline_obj
+
+    with patch("voice_to_notes.services.diarize.write_message", mock_write):
+        result = service.diarize(
+            request_id="req-1",
+            file_path="/fake/audio.wav",
+            audio_duration_sec=60.0,
+        )
+
+    # Filter for diarizing progress messages (not loading_diarization or done)
+    diarizing_msgs = [
+        m for m in written_messages
+        if m.type == "progress" and m.payload.get("stage") == "diarizing"
+        and "elapsed" in m.payload.get("message", "")
+    ]
+
+    # Should have at least 1 progress message (5s sleep / 2s interval = ~2 messages)
+    assert len(diarizing_msgs) >= 1, (
+        f"Expected at least 1 diarizing progress message, got {len(diarizing_msgs)}"
+    )
+
+    # Progress percent should be between 20 and 85
+    for msg in diarizing_msgs:
+        pct = msg.payload["percent"]
+        assert 20 <= pct <= 85, f"Progress {pct} out of expected range 20-85"
+
+    # Result should be valid
+    assert result.num_speakers == 1
+    assert result.speakers == ["SPEAKER_00"]
+
+
+def test_diarize_threading_error_propagation(monkeypatch):
+    """Test that errors from the background thread are properly raised."""
+    mock_pipeline_obj = MagicMock()
+    mock_pipeline_obj.side_effect = RuntimeError("Pipeline crashed")
+
+    service = DiarizeService()
+    service._pipeline = mock_pipeline_obj
+
+    with patch("voice_to_notes.services.diarize.write_message", lambda m: None):
+        with pytest.raises(RuntimeError, match="Pipeline crashed"):
+            service.diarize(
+                request_id="req-1",
+                file_path="/fake/audio.wav",
+                audio_duration_sec=30.0,
+            )
--- a/python/tests/test_messages.py
+++ b/python/tests/test_messages.py
@@ -3,8 +3,10 @@
 from voice_to_notes.ipc.messages import (
    IPCMessage,
    error_message,
+    partial_segment_message,
    progress_message,
    ready_message,
+    speaker_update_message,
 )


@@ -48,3 +50,16 @@ def test_ready_message():
    assert msg.type == "ready"
    assert msg.id == "system"
    assert "version" in msg.payload
+
+
+def test_partial_segment_message():
+    msg = partial_segment_message("req-1", {"index": 0, "text": "hello"})
+    assert msg.type == "pipeline.segment"
+    assert msg.payload["index"] == 0
+    assert msg.payload["text"] == "hello"
+
+
+def test_speaker_update_message():
+    msg = speaker_update_message("req-1", [{"index": 0, "speaker": "SPEAKER_00"}])
+    assert msg.type == "pipeline.speaker_update"
+    assert msg.payload["updates"][0]["speaker"] == "SPEAKER_00"
--- a/python/tests/test_pipeline.py
+++ b/python/tests/test_pipeline.py
@@ -88,3 +88,18 @@ def test_merge_results_no_speaker_segments():

    result = service._merge_results(transcription, [])
    assert result.segments[0].speaker is None
+
+
+def test_speaker_update_generation():
+    """Test that speaker updates are generated after merge."""
+    result = PipelineResult(
+        segments=[
+            PipelineSegment(text="Hello", start_ms=0, end_ms=1000, speaker="SPEAKER_00"),
+            PipelineSegment(text="World", start_ms=1000, end_ms=2000, speaker="SPEAKER_01"),
+            PipelineSegment(text="Foo", start_ms=2000, end_ms=3000, speaker=None),
+        ],
+    )
+    updates = [{"index": i, "speaker": seg.speaker} for i, seg in enumerate(result.segments) if seg.speaker]
+    assert len(updates) == 2
+    assert updates[0] == {"index": 0, "speaker": "SPEAKER_00"}
+    assert updates[1] == {"index": 1, "speaker": "SPEAKER_01"}
--- a/python/tests/test_protocol.py
+++ b/python/tests/test_protocol.py
@@ -5,16 +5,23 @@ import json

 from voice_to_notes.ipc.messages import IPCMessage
 from voice_to_notes.ipc.protocol import read_message, write_message
+import voice_to_notes.ipc.protocol as protocol


-def test_write_message(capsys):
-    msg = IPCMessage(id="req-1", type="pong", payload={"ok": True})
-    write_message(msg)
-    captured = capsys.readouterr()
-    parsed = json.loads(captured.out.strip())
-    assert parsed["id"] == "req-1"
-    assert parsed["type"] == "pong"
-    assert parsed["payload"]["ok"] is True
+def test_write_message():
+    buf = io.StringIO()
+    # Temporarily replace the IPC output stream
+    old_out = protocol._ipc_out
+    protocol._ipc_out = buf
+    try:
+        msg = IPCMessage(id="req-1", type="pong", payload={"ok": True})
+        write_message(msg)
+        parsed = json.loads(buf.getvalue().strip())
+        assert parsed["id"] == "req-1"
+        assert parsed["type"] == "pong"
+        assert parsed["payload"]["ok"] is True
+    finally:
+        protocol._ipc_out = old_out


 def test_read_message(monkeypatch):
--- a/python/tests/test_transcribe.py
+++ b/python/tests/test_transcribe.py
@@ -1,7 +1,10 @@
 """Tests for transcription service."""

+import inspect
+
 from voice_to_notes.services.transcribe import (
    SegmentResult,
+    TranscribeService,
    TranscriptionResult,
    WordResult,
    result_to_payload,
@@ -49,3 +52,149 @@ def test_result_to_payload_empty():
    assert payload["segments"] == []
    assert payload["language"] == ""
    assert payload["duration_ms"] == 0
+
+
+def test_on_segment_callback():
+    """Test that on_segment callback is invoked with correct SegmentResult and index."""
+    callback_args = []
+
+    def mock_callback(seg: SegmentResult, index: int):
+        callback_args.append((seg.text, index))
+
+    # Test that passing on_segment doesn't break the function signature
+    # (Full integration test would require mocking WhisperModel)
+    service = TranscribeService()
+    # Verify the parameter exists by checking the signature
+    sig = inspect.signature(service.transcribe)
+    assert "on_segment" in sig.parameters
+
+
+def test_progress_every_segment(monkeypatch):
+    """Verify a progress message is sent for every segment, not just every 5th."""
+    from unittest.mock import MagicMock, patch
+    from voice_to_notes.services.transcribe import TranscribeService
+
+    # Mock WhisperModel
+    mock_model = MagicMock()
+
+    # Create mock segments (8 of them to test > 5)
+    mock_segments = []
+    for i in range(8):
+        seg = MagicMock()
+        seg.start = i * 1.0
+        seg.end = (i + 1) * 1.0
+        seg.text = f"Segment {i}"
+        seg.words = []
+        mock_segments.append(seg)
+
+    # Mock info object
+    mock_info = MagicMock()
+    mock_info.language = "en"
+    mock_info.language_probability = 0.99
+    mock_info.duration = 8.0
+
+    mock_model.transcribe.return_value = (iter(mock_segments), mock_info)
+
+    # Track write_message calls
+    written_messages = []
+
+    def mock_write(msg):
+        written_messages.append(msg)
+
+    service = TranscribeService()
+    service._model = mock_model
+    service._current_model_name = "base"
+    service._current_device = "cpu"
+    service._current_compute_type = "int8"
+
+    with patch("voice_to_notes.services.transcribe.write_message", mock_write):
+        service.transcribe("req-1", "/fake/audio.wav")
+
+    # Filter for "transcribing" stage progress messages
+    transcribing_msgs = [
+        m for m in written_messages
+        if m.type == "progress" and m.payload.get("stage") == "transcribing"
+    ]
+
+    # Should have one per segment (8) + the initial "Starting transcription..." message
+    # The initial "Starting transcription..." is also stage "transcribing" — so 8 + 1 = 9
+    assert len(transcribing_msgs) >= 8, (
+        f"Expected at least 8 transcribing progress messages (one per segment), got {len(transcribing_msgs)}"
+    )
+
+
+def test_chunk_report_size_progress():
+    """Test CHUNK_REPORT_SIZE progress emission."""
+    from voice_to_notes.services.transcribe import CHUNK_REPORT_SIZE
+    assert CHUNK_REPORT_SIZE == 10
+
+
+def test_transcribe_chunked_with_mocked_ffmpeg(monkeypatch):
+    """Test transcribe_chunked with mocked ffmpeg/ffprobe and mocked WhisperModel."""
+    from unittest.mock import MagicMock, patch
+    from voice_to_notes.services.transcribe import TranscribeService, SegmentResult, WordResult
+
+    # Mock subprocess.run for ffprobe (returns duration of 700s = ~2 chunks at 300s each)
+    original_run = __import__("subprocess").run
+
+    def mock_subprocess_run(cmd, **kwargs):
+        if "ffprobe" in cmd:
+            result = MagicMock()
+            result.stdout = "700.0\n"
+            result.returncode = 0
+            return result
+        elif "ffmpeg" in cmd:
+            # Create an empty temp file (simulate chunk extraction)
+            # The output file is the last argument
+            import pathlib
+            output_file = cmd[-1]
+            pathlib.Path(output_file).touch()
+            result = MagicMock()
+            result.returncode = 0
+            return result
+        return original_run(cmd, **kwargs)
+
+    # Mock WhisperModel
+    mock_model = MagicMock()
+    def mock_transcribe_call(file_path, **kwargs):
+        mock_segments = []
+        for i in range(3):
+            seg = MagicMock()
+            seg.start = i * 1.0
+            seg.end = (i + 1) * 1.0
+            seg.text = f"Segment {i}"
+            seg.words = []
+            mock_segments.append(seg)
+        mock_info = MagicMock()
+        mock_info.language = "en"
+        mock_info.language_probability = 0.99
+        mock_info.duration = 300.0
+        return iter(mock_segments), mock_info
+
+    mock_model.transcribe = mock_transcribe_call
+
+    service = TranscribeService()
+    service._model = mock_model
+    service._current_model_name = "base"
+    service._current_device = "cpu"
+    service._current_compute_type = "int8"
+
+    written_messages = []
+    def mock_write(msg):
+        written_messages.append(msg)
+
+    with patch("subprocess.run", mock_subprocess_run), \
+         patch("voice_to_notes.services.transcribe.write_message", mock_write):
+        result = service.transcribe_chunked("req-1", "/fake/long_audio.wav")
+
+    # Should have segments from multiple chunks
+    assert len(result.segments) > 0
+
+    # Verify timestamp offsets — segments from chunk 1 should start at 0,
+    # segments from chunk 2 should be offset by 300000ms
+    if len(result.segments) > 3:
+        # Chunk 2 segments should have offset timestamps
+        assert result.segments[3].start_ms >= 300000
+
+    assert result.duration_ms == 700000
+    assert result.language == "en"
--- a/python/voice_to_notes.spec
+++ b/python/voice_to_notes.spec
@@ -0,0 +1,67 @@
+# -*- mode: python ; coding: utf-8 -*-
+"""PyInstaller spec for the Voice to Notes sidecar binary."""
+
+from PyInstaller.utils.hooks import collect_all
+
+block_cipher = None
+
+# Collect all files for packages that have shared libraries / data files
+# PyInstaller often misses these for ML packages
+ctranslate2_datas, ctranslate2_binaries, ctranslate2_hiddenimports = collect_all("ctranslate2")
+faster_whisper_datas, faster_whisper_binaries, faster_whisper_hiddenimports = collect_all(
+    "faster_whisper"
+)
+pyannote_datas, pyannote_binaries, pyannote_hiddenimports = collect_all("pyannote")
+
+a = Analysis(
+    ["voice_to_notes/main.py"],
+    pathex=[],
+    binaries=ctranslate2_binaries + faster_whisper_binaries + pyannote_binaries,
+    datas=ctranslate2_datas + faster_whisper_datas + pyannote_datas,
+    hiddenimports=[
+        "torch",
+        "torchaudio",
+        "huggingface_hub",
+        "pysubs2",
+        "openai",
+        "anthropic",
+        "litellm",
+    ]
+    + ctranslate2_hiddenimports
+    + faster_whisper_hiddenimports
+    + pyannote_hiddenimports,
+    hookspath=[],
+    hooksconfig={},
+    runtime_hooks=[],
+    excludes=["tkinter", "test", "unittest", "pip", "setuptools"],
+    win_no_prefer_redirects=False,
+    win_private_assemblies=False,
+    cipher=block_cipher,
+    noarchive=False,
+)
+
+pyz = PYZ(a.pure, a.zipped_data, cipher=block_cipher)
+
+exe = EXE(
+    pyz,
+    a.scripts,
+    [],
+    exclude_binaries=True,
+    name="voice-to-notes-sidecar",
+    debug=False,
+    bootloader_ignore_signals=False,
+    strip=False,
+    upx=True,
+    console=True,
+)
+
+coll = COLLECT(
+    exe,
+    a.binaries,
+    a.zipfiles,
+    a.datas,
+    strip=False,
+    upx=True,
+    upx_exclude=[],
+    name="voice-to-notes-sidecar",
+)
--- a/python/voice_to_notes/hardware/detect.py
+++ b/python/voice_to_notes/hardware/detect.py
@@ -2,7 +2,10 @@

 from __future__ import annotations

+import ctypes
 import os
+import platform
+import subprocess
 import sys
 from dataclasses import dataclass

@@ -21,6 +24,77 @@ class HardwareInfo:
    recommended_compute_type: str = "int8"


+def _detect_ram_mb() -> int:
+    """Detect total system RAM in MB (cross-platform).
+
+    Tries platform-specific methods in order:
+    1. Linux: read /proc/meminfo
+    2. macOS: sysctl hw.memsize
+    3. Windows: GlobalMemoryStatusEx via ctypes
+    4. Fallback: os.sysconf (most Unix systems)
+
+    Returns 0 if all methods fail.
+    """
+    # Linux: read /proc/meminfo
+    if sys.platform == "linux":
+        try:
+            with open("/proc/meminfo") as f:
+                for line in f:
+                    if line.startswith("MemTotal:"):
+                        # Value is in kB
+                        return int(line.split()[1]) // 1024
+        except (FileNotFoundError, ValueError, OSError):
+            pass
+
+    # macOS: sysctl hw.memsize (returns bytes)
+    if sys.platform == "darwin":
+        try:
+            result = subprocess.run(
+                ["sysctl", "-n", "hw.memsize"],
+                capture_output=True,
+                text=True,
+                check=True,
+            )
+            return int(result.stdout.strip()) // (1024 * 1024)
+        except (subprocess.SubprocessError, ValueError, OSError):
+            pass
+
+    # Windows: GlobalMemoryStatusEx via ctypes
+    if sys.platform == "win32":
+        try:
+
+            class MEMORYSTATUSEX(ctypes.Structure):
+                _fields_ = [
+                    ("dwLength", ctypes.c_ulong),
+                    ("dwMemoryLoad", ctypes.c_ulong),
+                    ("ullTotalPhys", ctypes.c_ulonglong),
+                    ("ullAvailPhys", ctypes.c_ulonglong),
+                    ("ullTotalPageFile", ctypes.c_ulonglong),
+                    ("ullAvailPageFile", ctypes.c_ulonglong),
+                    ("ullTotalVirtual", ctypes.c_ulonglong),
+                    ("ullAvailVirtual", ctypes.c_ulonglong),
+                    ("ullAvailExtendedVirtual", ctypes.c_ulonglong),
+                ]
+
+            mem_status = MEMORYSTATUSEX()
+            mem_status.dwLength = ctypes.sizeof(MEMORYSTATUSEX)
+            if ctypes.windll.kernel32.GlobalMemoryStatusEx(ctypes.byref(mem_status)):
+                return int(mem_status.ullTotalPhys) // (1024 * 1024)
+        except (AttributeError, OSError):
+            pass
+
+    # Fallback: os.sysconf (works on most Unix systems)
+    try:
+        page_size = os.sysconf("SC_PAGE_SIZE")
+        phys_pages = os.sysconf("SC_PHYS_PAGES")
+        if page_size > 0 and phys_pages > 0:
+            return (page_size * phys_pages) // (1024 * 1024)
+    except (ValueError, OSError, AttributeError):
+        pass
+
+    return 0
+
+
 def detect_hardware() -> HardwareInfo:
    """Detect available hardware and recommend model configuration."""
    info = HardwareInfo()
@@ -28,16 +102,8 @@ def detect_hardware() -> HardwareInfo:
    # CPU info
    info.cpu_cores = os.cpu_count() or 1

-    # RAM info
-    try:
-        with open("/proc/meminfo") as f:
-            for line in f:
-                if line.startswith("MemTotal:"):
-                    # Value is in kB
-                    info.ram_mb = int(line.split()[1]) // 1024
-                    break
-    except (FileNotFoundError, ValueError):
-        pass
+    # RAM info (cross-platform)
+    info.ram_mb = _detect_ram_mb()

    # CUDA detection
    try:
--- a/python/voice_to_notes/ipc/handlers.py
+++ b/python/voice_to_notes/ipc/handlers.py
@@ -88,6 +88,79 @@ def make_diarize_handler() -> HandlerFunc:
    return handler


+def make_diarize_download_handler() -> HandlerFunc:
+    """Create a handler that downloads/validates the diarization model."""
+    import os
+
+    def handler(msg: IPCMessage) -> IPCMessage:
+        payload = msg.payload
+        hf_token = payload.get("hf_token")
+
+        try:
+            import huggingface_hub
+
+            # Disable pyannote telemetry (has a bug in v4.0.4)
+            os.environ.setdefault("PYANNOTE_METRICS_ENABLED", "false")
+            from pyannote.audio import Pipeline
+
+            # Persist token globally so ALL huggingface_hub downloads use auth.
+            # Setting env var alone isn't enough — pyannote's internal sub-downloads
+            # (e.g. PLDA.from_pretrained) don't forward the token= parameter.
+            # login() writes the token to ~/.cache/huggingface/token which
+            # huggingface_hub reads automatically for all downloads.
+            if hf_token:
+                os.environ["HF_TOKEN"] = hf_token
+                huggingface_hub.login(token=hf_token, add_to_git_credential=False)
+
+            # Pre-download sub-models that pyannote loads internally.
+            # This ensures they're cached before Pipeline.from_pretrained
+            # tries to load them (where token forwarding can fail).
+            sub_models = [
+                "pyannote/segmentation-3.0",
+                "pyannote/speaker-diarization-community-1",
+            ]
+            for model_id in sub_models:
+                print(f"[sidecar] Pre-downloading {model_id}...", file=sys.stderr, flush=True)
+                huggingface_hub.snapshot_download(model_id, token=hf_token)
+
+            print("[sidecar] Downloading diarization pipeline...", file=sys.stderr, flush=True)
+            pipeline = Pipeline.from_pretrained(
+                "pyannote/speaker-diarization-3.1",
+                token=hf_token,
+            )
+            print("[sidecar] Diarization model downloaded successfully", file=sys.stderr, flush=True)
+            return IPCMessage(
+                id=msg.id,
+                type="diarize.download.result",
+                payload={"ok": True},
+            )
+        except Exception as e:
+            error_msg = str(e)
+            print(f"[sidecar] Model download error: {error_msg}", file=sys.stderr, flush=True)
+            # Make common errors more user-friendly
+            if "403" in error_msg or "gated" in error_msg.lower():
+                # Try to extract the specific model name from the error
+                import re
+                model_match = re.search(r"pyannote/[\w-]+", error_msg)
+                if model_match:
+                    model_name = model_match.group(0)
+                    error_msg = (
+                        f"Access denied for {model_name}. "
+                        f"Please visit huggingface.co/{model_name} "
+                        f"and accept the license agreement, then try again."
+                    )
+                else:
+                    error_msg = (
+                        "Access denied. Please accept the license agreements for all "
+                        "required pyannote models on HuggingFace."
+                    )
+            elif "401" in error_msg:
+                error_msg = "Invalid token. Please check your HuggingFace token."
+            return error_message(msg.id, "download_error", error_msg)
+
+    return handler
+
+
 def make_pipeline_handler() -> HandlerFunc:
    """Create a full pipeline handler (transcribe + diarize + merge)."""
    from voice_to_notes.services.pipeline import PipelineService, pipeline_result_to_payload
@@ -107,6 +180,7 @@ def make_pipeline_handler() -> HandlerFunc:
            min_speakers=payload.get("min_speakers"),
            max_speakers=payload.get("max_speakers"),
            skip_diarization=payload.get("skip_diarization", False),
+            hf_token=payload.get("hf_token"),
        )
        return IPCMessage(
            id=msg.id,
@@ -186,10 +260,12 @@ def make_ai_chat_handler() -> HandlerFunc:
                    model=config.get("model", "claude-sonnet-4-6"),
                ))
            elif provider_name == "litellm":
-                from voice_to_notes.providers.litellm_provider import LiteLLMProvider
+                from voice_to_notes.providers.litellm_provider import OpenAICompatibleProvider

-                service.register_provider("litellm", LiteLLMProvider(
+                service.register_provider("litellm", OpenAICompatibleProvider(
                    model=config.get("model", "gpt-4o-mini"),
+                    api_key=config.get("api_key"),
+                    api_base=config.get("api_base"),
                ))
            return IPCMessage(
                id=msg.id,
--- a/python/voice_to_notes/ipc/messages.py
+++ b/python/voice_to_notes/ipc/messages.py
@@ -34,6 +34,14 @@ def progress_message(request_id: str, percent: int, stage: str, message: str) ->
    )


+def partial_segment_message(request_id: str, segment_data: dict) -> IPCMessage:
+    return IPCMessage(id=request_id, type="pipeline.segment", payload=segment_data)
+
+
+def speaker_update_message(request_id: str, updates: list[dict]) -> IPCMessage:
+    return IPCMessage(id=request_id, type="pipeline.speaker_update", payload={"updates": updates})
+
+
 def error_message(request_id: str, code: str, message: str) -> IPCMessage:
    return IPCMessage(
        id=request_id,
--- a/python/voice_to_notes/ipc/protocol.py
+++ b/python/voice_to_notes/ipc/protocol.py
@@ -1,13 +1,53 @@
-"""JSON-line protocol reader/writer over stdin/stdout."""
+"""JSON-line protocol reader/writer over stdin/stdout.
+
+IMPORTANT: stdout is reserved exclusively for IPC messages.
+At init time we save the real stdout, then redirect sys.stdout → stderr
+so that any rogue print() calls from libraries don't corrupt the IPC stream.
+"""

 from __future__ import annotations

+import io
 import json
+import os
 import sys
 from typing import Any

 from voice_to_notes.ipc.messages import IPCMessage

+# Save the real stdout fd for IPC before any library can pollute it.
+# Then redirect sys.stdout to stderr so library prints go to stderr.
+_ipc_out: io.TextIOWrapper | None = None
+
+
+def init_ipc() -> None:
+    """Capture real stdout for IPC and redirect sys.stdout to stderr.
+
+    Must be called once at sidecar startup, before importing any ML libraries.
+    """
+    global _ipc_out
+    if _ipc_out is not None:
+        return  # already initialised
+
+    # Duplicate the real stdout fd so we keep it even after redirect
+    real_stdout_fd = os.dup(sys.stdout.fileno())
+    _ipc_out = io.TextIOWrapper(
+        io.BufferedWriter(io.FileIO(real_stdout_fd, "w")),
+        encoding="utf-8",
+        line_buffering=True,
+    )
+
+    # Redirect sys.stdout → stderr so print() from libraries goes to stderr
+    sys.stdout = sys.stderr
+
+
+def _get_ipc_out() -> io.TextIOWrapper:
+    """Return the IPC output stream, falling back to sys.__stdout__."""
+    if _ipc_out is not None:
+        return _ipc_out
+    # Fallback if init_ipc() was never called (e.g. in tests)
+    return sys.__stdout__
+

 def read_message() -> IPCMessage | None:
    """Read a single JSON-line message from stdin. Returns None on EOF."""
@@ -29,17 +69,19 @@ def read_message() -> IPCMessage | None:


 def write_message(msg: IPCMessage) -> None:
-    """Write a JSON-line message to stdout."""
+    """Write a JSON-line message to the IPC channel (real stdout)."""
+    out = _get_ipc_out()
    line = json.dumps(msg.to_dict(), separators=(",", ":"))
-    sys.stdout.write(line + "\n")
-    sys.stdout.flush()
+    out.write(line + "\n")
+    out.flush()


 def write_dict(data: dict[str, Any]) -> None:
-    """Write a raw dict as a JSON-line message to stdout."""
+    """Write a raw dict as a JSON-line message to the IPC channel."""
+    out = _get_ipc_out()
    line = json.dumps(data, separators=(",", ":"))
-    sys.stdout.write(line + "\n")
-    sys.stdout.flush()
+    out.write(line + "\n")
+    out.flush()


 def _log(message: str) -> None:
--- a/python/voice_to_notes/main.py
+++ b/python/voice_to_notes/main.py
@@ -5,18 +5,25 @@ from __future__ import annotations
 import signal
 import sys

-from voice_to_notes.ipc.handlers import (
+# CRITICAL: Capture real stdout for IPC *before* importing any ML libraries
+# that might print to stdout and corrupt the JSON-line protocol.
+from voice_to_notes.ipc.protocol import init_ipc
+
+init_ipc()
+
+from voice_to_notes.ipc.handlers import (  # noqa: E402
    HandlerRegistry,
    hardware_detect_handler,
    make_ai_chat_handler,
+    make_diarize_download_handler,
    make_diarize_handler,
    make_export_handler,
    make_pipeline_handler,
    make_transcribe_handler,
    ping_handler,
 )
-from voice_to_notes.ipc.messages import ready_message
-from voice_to_notes.ipc.protocol import read_message, write_message
+from voice_to_notes.ipc.messages import ready_message  # noqa: E402
+from voice_to_notes.ipc.protocol import read_message, write_message  # noqa: E402


 def create_registry() -> HandlerRegistry:
@@ -26,6 +33,7 @@ def create_registry() -> HandlerRegistry:
    registry.register("transcribe.start", make_transcribe_handler())
    registry.register("hardware.detect", hardware_detect_handler)
    registry.register("diarize.start", make_diarize_handler())
+    registry.register("diarize.download", make_diarize_download_handler())
    registry.register("pipeline.start", make_pipeline_handler())
    registry.register("export.start", make_export_handler())
    registry.register("ai.chat", make_ai_chat_handler())
--- a/python/voice_to_notes/providers/litellm_provider.py
+++ b/python/voice_to_notes/providers/litellm_provider.py
@@ -1,4 +1,4 @@
-"""LiteLLM provider — multi-provider gateway."""
+"""OpenAI-compatible provider — works with any OpenAI-compatible API endpoint."""

 from __future__ import annotations

@@ -7,36 +7,44 @@ from typing import Any
 from voice_to_notes.providers.base import AIProvider


-class LiteLLMProvider(AIProvider):
-    """Routes through LiteLLM for access to 100+ LLM providers."""
+class OpenAICompatibleProvider(AIProvider):
+    """Connects to any OpenAI-compatible API (LiteLLM proxy, Ollama, vLLM, etc.)."""

-    def __init__(self, model: str = "gpt-4o-mini", **kwargs: Any) -> None:
+    def __init__(
+        self,
+        api_key: str | None = None,
+        api_base: str | None = None,
+        model: str = "gpt-4o-mini",
+        **kwargs: Any,
+    ) -> None:
+        self._api_key = api_key or "sk-no-key"
+        self._api_base = api_base
        self._model = model
        self._extra_kwargs = kwargs

    def chat(self, messages: list[dict[str, str]], **kwargs: Any) -> str:
-        try:
-            import litellm
-        except ImportError:
-            raise RuntimeError("litellm package is required. Install with: pip install litellm")
+        from openai import OpenAI

-        merged_kwargs = {**self._extra_kwargs, **kwargs}
-        response = litellm.completion(
-            model=merged_kwargs.get("model", self._model),
+        client_kwargs: dict[str, Any] = {"api_key": self._api_key}
+        if self._api_base:
+            client_kwargs["base_url"] = self._api_base
+
+        client = OpenAI(**client_kwargs)
+        response = client.chat.completions.create(
+            model=kwargs.get("model", self._model),
            messages=messages,
-            temperature=merged_kwargs.get("temperature", 0.7),
-            max_tokens=merged_kwargs.get("max_tokens", 2048),
+            temperature=kwargs.get("temperature", 0.7),
+            max_tokens=kwargs.get("max_tokens", 2048),
        )
        return response.choices[0].message.content or ""

    def is_available(self) -> bool:
        try:
-            import litellm  # noqa: F401
-
-            return True
+            import openai  # noqa: F401
+            return bool(self._api_key and self._api_base)
        except ImportError:
            return False

    @property
    def name(self) -> str:
-        return "LiteLLM"
+        return "OpenAI Compatible"
--- a/python/voice_to_notes/services/ai_provider.py
+++ b/python/voice_to_notes/services/ai_provider.py
@@ -92,7 +92,7 @@ class AIProviderService:
 def create_default_service() -> AIProviderService:
    """Create an AIProviderService with all supported providers registered."""
    from voice_to_notes.providers.anthropic_provider import AnthropicProvider
-    from voice_to_notes.providers.litellm_provider import LiteLLMProvider
+    from voice_to_notes.providers.litellm_provider import OpenAICompatibleProvider
    from voice_to_notes.providers.local_provider import LocalProvider
    from voice_to_notes.providers.openai_provider import OpenAIProvider

@@ -100,5 +100,5 @@ def create_default_service() -> AIProviderService:
    service.register_provider("local", LocalProvider())
    service.register_provider("openai", OpenAIProvider())
    service.register_provider("anthropic", AnthropicProvider())
-    service.register_provider("litellm", LiteLLMProvider())
+    service.register_provider("litellm", OpenAICompatibleProvider())
    return service
--- a/python/voice_to_notes/services/diarize.py
+++ b/python/voice_to_notes/services/diarize.py
@@ -2,15 +2,69 @@

 from __future__ import annotations

+import os
+import subprocess
 import sys
+import tempfile
+import threading
 import time
 from dataclasses import dataclass, field
+from pathlib import Path
 from typing import Any

+# Disable pyannote telemetry — it has a bug in v4.0.4 where
+# np.isfinite(None) crashes when max_speakers is not set.
+os.environ.setdefault("PYANNOTE_METRICS_ENABLED", "false")
+
+from voice_to_notes.utils.ffmpeg import get_ffmpeg_path
 from voice_to_notes.ipc.messages import progress_message
 from voice_to_notes.ipc.protocol import write_message


+def _ensure_wav(file_path: str) -> tuple[str, str | None]:
+    """Convert audio to 16kHz mono WAV if needed.
+
+    pyannote.audio v4.0.4 has a bug where its AudioDecoder returns
+    duration=None for some formats (FLAC, etc.), causing crashes.
+    Converting to WAV ensures the duration header is always present.
+
+    Returns:
+        (path_to_use, temp_path_or_None)
+        If conversion was needed, temp_path is the WAV file to clean up.
+    """
+    ext = Path(file_path).suffix.lower()
+    if ext == ".wav":
+        return file_path, None
+
+    tmp = tempfile.NamedTemporaryFile(suffix=".wav", delete=False)
+    tmp.close()
+    try:
+        subprocess.run(
+            [
+                get_ffmpeg_path(), "-y", "-i", file_path,
+                "-ar", "16000", "-ac", "1", "-c:a", "pcm_s16le",
+                tmp.name,
+            ],
+            check=True,
+            capture_output=True,
+        )
+        print(
+            f"[sidecar] Converted {ext} to WAV for diarization",
+            file=sys.stderr,
+            flush=True,
+        )
+        return tmp.name, tmp.name
+    except (subprocess.CalledProcessError, FileNotFoundError) as e:
+        # ffmpeg not available or failed — try original file and hope for the best
+        print(
+            f"[sidecar] WAV conversion failed ({e}), using original file",
+            file=sys.stderr,
+            flush=True,
+        )
+        os.unlink(tmp.name)
+        return file_path, None
+
+
@dataclass
 class SpeakerSegment:
    """A time span assigned to a speaker."""
@@ -35,45 +89,59 @@ class DiarizeService:
    def __init__(self) -> None:
        self._pipeline: Any = None

-    def _ensure_pipeline(self) -> Any:
+    def _ensure_pipeline(self, hf_token: str | None = None) -> Any:
        """Load the pyannote diarization pipeline (lazy)."""
        if self._pipeline is not None:
            return self._pipeline

        print("[sidecar] Loading pyannote diarization pipeline...", file=sys.stderr, flush=True)

-        try:
-            from pyannote.audio import Pipeline
+        # Use token from argument, fall back to environment variable
+        if not hf_token:
+            hf_token = os.environ.get("HF_TOKEN") or os.environ.get("HUGGING_FACE_HUB_TOKEN") or None

-            self._pipeline = Pipeline.from_pretrained(
-                "pyannote/speaker-diarization-3.1",
-                use_auth_token=False,
-            )
-        except Exception:
-            # Fall back to a simpler approach if the model isn't available
-            # pyannote requires HuggingFace token for some models
-            # Try the community model first
+        # Persist token globally so ALL huggingface_hub sub-downloads use auth.
+        # Pyannote has internal dependencies that don't forward the token= param.
+        if hf_token:
+            os.environ["HF_TOKEN"] = hf_token
+            import huggingface_hub
+            huggingface_hub.login(token=hf_token, add_to_git_credential=False)
+
+        models = [
+            "pyannote/speaker-diarization-3.1",
+            "pyannote/speaker-diarization",
+        ]
+
+        last_error: Exception | None = None
+        for model_name in models:
            try:
                from pyannote.audio import Pipeline

-                self._pipeline = Pipeline.from_pretrained(
-                    "pyannote/speaker-diarization",
-                    use_auth_token=False,
-                )
+                self._pipeline = Pipeline.from_pretrained(model_name, token=hf_token)
+                print(f"[sidecar] Loaded diarization model: {model_name}", file=sys.stderr, flush=True)
+                # Move pipeline to GPU if available
+                try:
+                    import torch
+                    if torch.cuda.is_available():
+                        self._pipeline = self._pipeline.to(torch.device("cuda"))
+                        print(f"[sidecar] Diarization pipeline moved to GPU", file=sys.stderr, flush=True)
+                except Exception as e:
+                    print(f"[sidecar] GPU not available for diarization: {e}", file=sys.stderr, flush=True)
+                return self._pipeline
            except Exception as e:
+                last_error = e
                print(
-                    f"[sidecar] Warning: Could not load pyannote pipeline: {e}",
+                    f"[sidecar] Warning: Could not load {model_name}: {e}",
                    file=sys.stderr,
                    flush=True,
                )
-                raise RuntimeError(
-                    "pyannote.audio pipeline not available. "
-                    "You may need to accept the model license at "
-                    "https://huggingface.co/pyannote/speaker-diarization-3.1 "
-                    "and set a HF_TOKEN environment variable."
-                ) from e

-        return self._pipeline
+        raise RuntimeError(
+            "pyannote.audio pipeline not available. "
+            "You may need to accept the model license at "
+            "https://huggingface.co/pyannote/speaker-diarization-3.1 "
+            "and set a HF_TOKEN environment variable."
+        ) from last_error

    def diarize(
        self,
@@ -82,6 +150,8 @@ class DiarizeService:
        num_speakers: int | None = None,
        min_speakers: int | None = None,
        max_speakers: int | None = None,
+        hf_token: str | None = None,
+        audio_duration_sec: float | None = None,
    ) -> DiarizationResult:
        """Run speaker diarization on an audio file.

@@ -99,7 +169,7 @@ class DiarizeService:
            progress_message(request_id, 0, "loading_diarization", "Loading diarization model...")
        )

-        pipeline = self._ensure_pipeline()
+        pipeline = self._ensure_pipeline(hf_token=hf_token)

        write_message(
            progress_message(request_id, 20, "diarizing", "Running speaker diarization...")
@@ -116,8 +186,55 @@ class DiarizeService:
        if max_speakers is not None:
            kwargs["max_speakers"] = max_speakers

-        # Run diarization
-        diarization = pipeline(file_path, **kwargs)
+        # Convert to WAV to work around pyannote v4.0.4 duration bug
+        audio_path, temp_wav = _ensure_wav(file_path)
+
+        print(
+            f"[sidecar] Running diarization on {audio_path} with kwargs: {kwargs}",
+            file=sys.stderr,
+            flush=True,
+        )
+
+        # Run diarization in background thread for progress reporting
+        result_holder: list = [None]
+        error_holder: list[Exception | None] = [None]
+        done_event = threading.Event()
+
+        def _run():
+            try:
+                result_holder[0] = pipeline(audio_path, **kwargs)
+            except Exception as e:
+                error_holder[0] = e
+            finally:
+                done_event.set()
+
+        thread = threading.Thread(target=_run, daemon=True)
+        thread.start()
+
+        elapsed = 0.0
+        estimated_total = max(audio_duration_sec * 0.5, 30.0) if audio_duration_sec else 120.0
+        while not done_event.wait(timeout=2.0):
+            elapsed += 2.0
+            pct = min(20 + int((elapsed / estimated_total) * 65), 85)
+            write_message(progress_message(
+                request_id, pct, "diarizing",
+                f"Analyzing speakers ({int(elapsed)}s elapsed)..."))
+
+        thread.join()
+
+        # Clean up temp file
+        if temp_wav:
+            os.unlink(temp_wav)
+
+        if error_holder[0] is not None:
+            raise error_holder[0]
+        raw_result = result_holder[0]
+
+        # pyannote 4.0+ returns DiarizeOutput; older versions return Annotation directly
+        if hasattr(raw_result, "speaker_diarization"):
+            diarization = raw_result.speaker_diarization
+        else:
+            diarization = raw_result

        # Convert pyannote output to our format
        result = DiarizationResult()
--- a/python/voice_to_notes/services/pipeline.py
+++ b/python/voice_to_notes/services/pipeline.py
@@ -2,13 +2,19 @@

 from __future__ import annotations

+import concurrent.futures
 import sys
 import time
 from dataclasses import dataclass, field
 from typing import Any

-from voice_to_notes.ipc.messages import progress_message
+from voice_to_notes.ipc.messages import (
+    partial_segment_message,
+    progress_message,
+    speaker_update_message,
+)
 from voice_to_notes.ipc.protocol import write_message
+from voice_to_notes.utils.ffmpeg import get_ffprobe_path
 from voice_to_notes.services.diarize import DiarizeService, SpeakerSegment
 from voice_to_notes.services.transcribe import (
    SegmentResult,
@@ -60,6 +66,7 @@ class PipelineService:
        min_speakers: int | None = None,
        max_speakers: int | None = None,
        skip_diarization: bool = False,
+        hf_token: str | None = None,
    ) -> PipelineResult:
        """Run the full transcription + diarization pipeline.

@@ -77,22 +84,59 @@ class PipelineService:
        """
        start_time = time.time()

-        # Step 1: Transcribe
+        # Step 0: Probe audio duration for conditional chunked transcription
        write_message(
            progress_message(request_id, 0, "pipeline", "Starting transcription pipeline...")
        )

-        transcription = self._transcribe_service.transcribe(
-            request_id=request_id,
-            file_path=file_path,
-            model_name=model_name,
-            device=device,
-            compute_type=compute_type,
-            language=language,
-        )
+        def _emit_segment(seg: SegmentResult, index: int) -> None:
+            write_message(partial_segment_message(request_id, {
+                "index": index,
+                "text": seg.text,
+                "start_ms": seg.start_ms,
+                "end_ms": seg.end_ms,
+                "words": [{"word": w.word, "start_ms": w.start_ms, "end_ms": w.end_ms, "confidence": w.confidence} for w in seg.words],
+            }))
+
+        audio_duration_sec = None
+        try:
+            import subprocess
+            probe_result = subprocess.run(
+                [get_ffprobe_path(), "-v", "quiet", "-show_entries", "format=duration",
+                 "-of", "default=noprint_wrappers=1:nokey=1", file_path],
+                capture_output=True, text=True, check=True,
+            )
+            audio_duration_sec = float(probe_result.stdout.strip())
+        except (subprocess.CalledProcessError, FileNotFoundError, ValueError):
+            pass
+
+        def _run_transcription() -> TranscriptionResult:
+            """Run transcription (chunked or standard based on duration)."""
+            from voice_to_notes.services.transcribe import LARGE_FILE_THRESHOLD_SEC
+            if audio_duration_sec and audio_duration_sec > LARGE_FILE_THRESHOLD_SEC:
+                return self._transcribe_service.transcribe_chunked(
+                    request_id=request_id,
+                    file_path=file_path,
+                    model_name=model_name,
+                    device=device,
+                    compute_type=compute_type,
+                    language=language,
+                    on_segment=_emit_segment,
+                )
+            else:
+                return self._transcribe_service.transcribe(
+                    request_id=request_id,
+                    file_path=file_path,
+                    model_name=model_name,
+                    device=device,
+                    compute_type=compute_type,
+                    language=language,
+                    on_segment=_emit_segment,
+                )

        if skip_diarization:
-            # Convert transcription directly without speaker labels
+            # Sequential: transcribe only, no diarization needed
+            transcription = _run_transcription()
            result = PipelineResult(
                language=transcription.language,
                language_probability=transcription.language_probability,
@@ -110,27 +154,83 @@ class PipelineService:
                )
            return result

-        # Step 2: Diarize
+        # Parallel execution: run transcription (0-45%) and diarization (45-90%)
+        # concurrently, then merge (90-100%).
        write_message(
-            progress_message(request_id, 50, "pipeline", "Starting speaker diarization...")
+            progress_message(
+                request_id, 0, "pipeline",
+                "Starting transcription and diarization in parallel..."
+            )
        )

-        diarization = self._diarize_service.diarize(
-            request_id=request_id,
-            file_path=file_path,
-            num_speakers=num_speakers,
-            min_speakers=min_speakers,
-            max_speakers=max_speakers,
-        )
+        diarization = None
+        diarization_error = None

-        # Step 3: Merge
-        write_message(
-            progress_message(request_id, 90, "pipeline", "Merging transcript with speakers...")
-        )
+        with concurrent.futures.ThreadPoolExecutor(max_workers=2) as executor:
+            transcription_future = executor.submit(_run_transcription)

-        result = self._merge_results(transcription, diarization.speaker_segments)
-        result.speakers = diarization.speakers
-        result.num_speakers = diarization.num_speakers
+            # Use probed audio_duration_sec for diarization progress estimation
+            # (transcription hasn't finished yet, so we can't use transcription.duration_ms)
+            diarization_future = executor.submit(
+                self._diarize_service.diarize,
+                request_id=request_id,
+                file_path=file_path,
+                num_speakers=num_speakers,
+                min_speakers=min_speakers,
+                max_speakers=max_speakers,
+                hf_token=hf_token,
+                audio_duration_sec=audio_duration_sec,
+            )
+
+            # Wait for both futures. We need the transcription result regardless,
+            # but diarization may fail gracefully.
+            transcription = transcription_future.result()
+            write_message(
+                progress_message(request_id, 45, "pipeline", "Transcription complete")
+            )
+
+            try:
+                diarization = diarization_future.result()
+            except Exception as e:
+                import traceback
+                diarization_error = e
+                print(
+                    f"[sidecar] Diarization failed, falling back to transcription-only: {e}",
+                    file=sys.stderr,
+                    flush=True,
+                )
+                traceback.print_exc(file=sys.stderr)
+                write_message(
+                    progress_message(
+                        request_id, 80, "pipeline",
+                        f"Diarization failed ({e}), using transcription only..."
+                    )
+                )
+
+        # Step 3: Merge (or skip if diarization failed)
+        if diarization is not None:
+            write_message(
+                progress_message(request_id, 90, "merging", "Merging transcript with speakers...")
+            )
+            result = self._merge_results(transcription, diarization.speaker_segments)
+            result.speakers = diarization.speakers
+            result.num_speakers = diarization.num_speakers
+        else:
+            result = PipelineResult(
+                language=transcription.language,
+                language_probability=transcription.language_probability,
+                duration_ms=transcription.duration_ms,
+            )
+            for seg in transcription.segments:
+                result.segments.append(
+                    PipelineSegment(
+                        text=seg.text,
+                        start_ms=seg.start_ms,
+                        end_ms=seg.end_ms,
+                        speaker=None,
+                        words=seg.words,
+                    )
+                )

        elapsed = time.time() - start_time
        print(
@@ -140,6 +240,10 @@ class PipelineService:
            flush=True,
        )

+        updates = [{"index": i, "speaker": seg.speaker} for i, seg in enumerate(result.segments) if seg.speaker]
+        if updates:
+            write_message(speaker_update_message(request_id, updates))
+
        write_message(
            progress_message(request_id, 100, "done", "Pipeline complete")
        )
--- a/python/voice_to_notes/services/transcribe.py
+++ b/python/voice_to_notes/services/transcribe.py
@@ -4,6 +4,7 @@ from __future__ import annotations

 import sys
 import time
+from collections.abc import Callable
 from dataclasses import dataclass, field
 from typing import Any

@@ -11,6 +12,10 @@ from faster_whisper import WhisperModel

 from voice_to_notes.ipc.messages import progress_message
 from voice_to_notes.ipc.protocol import write_message
+from voice_to_notes.utils.ffmpeg import get_ffmpeg_path, get_ffprobe_path
+
+CHUNK_REPORT_SIZE = 10
+LARGE_FILE_THRESHOLD_SEC = 3600  # 1 hour


@dataclass
@@ -90,6 +95,7 @@ class TranscribeService:
        device: str = "cpu",
        compute_type: str = "int8",
        language: str | None = None,
+        on_segment: Callable[[SegmentResult, int], None] | None = None,
    ) -> TranscriptionResult:
        """Transcribe an audio file with word-level timestamps.

@@ -145,16 +151,23 @@ class TranscribeService:
                )
            )

-            # Send progress every few segments
-            if segment_count % 5 == 0:
-                write_message(
-                    progress_message(
-                        request_id,
-                        progress_pct,
-                        "transcribing",
-                        f"Processed {segment_count} segments...",
-                    )
+            if on_segment:
+                on_segment(result.segments[-1], segment_count - 1)
+
+            write_message(
+                progress_message(
+                    request_id,
+                    progress_pct,
+                    "transcribing",
+                    f"Transcribing segment {segment_count} ({progress_pct}% of audio)...",
                )
+            )
+
+            if segment_count % CHUNK_REPORT_SIZE == 0:
+                write_message(progress_message(
+                    request_id, progress_pct, "transcribing",
+                    f"Completed chunk of {CHUNK_REPORT_SIZE} segments "
+                    f"({segment_count} total, {progress_pct}% of audio)..."))

        elapsed = time.time() - start_time
        print(
@@ -166,6 +179,113 @@ class TranscribeService:
        write_message(progress_message(request_id, 100, "done", "Transcription complete"))
        return result

+    def transcribe_chunked(
+        self,
+        request_id: str,
+        file_path: str,
+        model_name: str = "base",
+        device: str = "cpu",
+        compute_type: str = "int8",
+        language: str | None = None,
+        on_segment: Callable[[SegmentResult, int], None] | None = None,
+        chunk_duration_sec: int = 300,
+    ) -> TranscriptionResult:
+        """Transcribe a large audio file by splitting into chunks.
+
+        Uses ffmpeg to split the file into chunks, transcribes each chunk,
+        then merges the results with corrected timestamps.
+
+        Falls back to standard transcribe() if ffmpeg is not available.
+        """
+        import subprocess
+        import tempfile
+
+        # Get total duration via ffprobe
+        try:
+            probe_result = subprocess.run(
+                [get_ffprobe_path(), "-v", "quiet", "-show_entries", "format=duration",
+                 "-of", "default=noprint_wrappers=1:nokey=1", file_path],
+                capture_output=True, text=True, check=True,
+            )
+            total_duration = float(probe_result.stdout.strip())
+        except (subprocess.CalledProcessError, FileNotFoundError, ValueError):
+            # ffprobe not available or failed — fall back to standard transcription
+            write_message(progress_message(
+                request_id, 5, "transcribing",
+                "ffmpeg not available, using standard transcription..."))
+            return self.transcribe(request_id, file_path, model_name, device,
+                                   compute_type, language, on_segment=on_segment)
+
+        num_chunks = max(1, int(total_duration / chunk_duration_sec) + 1)
+        write_message(progress_message(
+            request_id, 5, "transcribing",
+            f"Splitting {total_duration:.0f}s file into {num_chunks} chunks..."))
+
+        merged_result = TranscriptionResult()
+        global_segment_index = 0
+
+        for chunk_idx in range(num_chunks):
+            chunk_start = chunk_idx * chunk_duration_sec
+            if chunk_start >= total_duration:
+                break
+
+            chunk_start_ms = int(chunk_start * 1000)
+
+            # Extract chunk to temp file
+            tmp = tempfile.NamedTemporaryFile(suffix=".wav", delete=False)
+            tmp.close()
+            try:
+                subprocess.run(
+                    [get_ffmpeg_path(), "-y", "-ss", str(chunk_start),
+                     "-t", str(chunk_duration_sec),
+                     "-i", file_path,
+                     "-ar", "16000", "-ac", "1", "-c:a", "pcm_s16le",
+                     tmp.name],
+                    capture_output=True, check=True,
+                )
+
+                # Wrap on_segment to offset the index
+                chunk_on_segment = None
+                if on_segment:
+                    base_index = global_segment_index
+                    def chunk_on_segment(seg: SegmentResult, idx: int, _base=base_index) -> None:
+                        on_segment(seg, _base + idx)
+
+                chunk_result = self.transcribe(
+                    request_id, tmp.name, model_name, device,
+                    compute_type, language, on_segment=chunk_on_segment,
+                )
+
+                # Offset timestamps and merge
+                for seg in chunk_result.segments:
+                    seg.start_ms += chunk_start_ms
+                    seg.end_ms += chunk_start_ms
+                    for word in seg.words:
+                        word.start_ms += chunk_start_ms
+                        word.end_ms += chunk_start_ms
+                    merged_result.segments.append(seg)
+
+                global_segment_index += len(chunk_result.segments)
+
+                # Take language from first chunk
+                if chunk_idx == 0:
+                    merged_result.language = chunk_result.language
+                    merged_result.language_probability = chunk_result.language_probability
+
+            finally:
+                import os
+                os.unlink(tmp.name)
+
+            # Chunk progress
+            chunk_pct = min(10 + int(((chunk_idx + 1) / num_chunks) * 80), 90)
+            write_message(progress_message(
+                request_id, chunk_pct, "transcribing",
+                f"Completed chunk {chunk_idx + 1}/{num_chunks}..."))
+
+        merged_result.duration_ms = int(total_duration * 1000)
+        write_message(progress_message(request_id, 100, "done", "Transcription complete"))
+        return merged_result
+

 def result_to_payload(result: TranscriptionResult) -> dict[str, Any]:
    """Convert TranscriptionResult to IPC payload dict."""
--- a/python/voice_to_notes/utils/ffmpeg.py
+++ b/python/voice_to_notes/utils/ffmpeg.py
@@ -0,0 +1,43 @@
+"""Resolve ffmpeg/ffprobe paths for both frozen and development builds."""
+
+from __future__ import annotations
+
+import os
+import sys
+
+
+def get_ffmpeg_path() -> str:
+    """Return the path to the ffmpeg binary.
+
+    When running as a frozen PyInstaller bundle, looks next to sys.executable.
+    Otherwise falls back to the system PATH.
+    """
+    if getattr(sys, "frozen", False):
+        # Frozen PyInstaller bundle — ffmpeg is next to the sidecar binary
+        bundle_dir = os.path.dirname(sys.executable)
+        candidates = [
+            os.path.join(bundle_dir, "ffmpeg.exe" if sys.platform == "win32" else "ffmpeg"),
+            os.path.join(bundle_dir, "ffmpeg"),
+        ]
+        for path in candidates:
+            if os.path.isfile(path):
+                return path
+    return "ffmpeg"
+
+
+def get_ffprobe_path() -> str:
+    """Return the path to the ffprobe binary.
+
+    When running as a frozen PyInstaller bundle, looks next to sys.executable.
+    Otherwise falls back to the system PATH.
+    """
+    if getattr(sys, "frozen", False):
+        bundle_dir = os.path.dirname(sys.executable)
+        candidates = [
+            os.path.join(bundle_dir, "ffprobe.exe" if sys.platform == "win32" else "ffprobe"),
+            os.path.join(bundle_dir, "ffprobe"),
+        ]
+        for path in candidates:
+            if os.path.isfile(path):
+                return path
+    return "ffprobe"
--- a/src-tauri/binaries/.gitkeep
+++ b/src-tauri/binaries/.gitkeep
--- a/src-tauri/src/commands/ai.rs
+++ b/src-tauri/src/commands/ai.rs
@@ -39,7 +39,11 @@ pub fn ai_chat(
    if response.msg_type == "error" {
        return Err(format!(
            "AI error: {}",
-            response.payload.get("message").and_then(|v| v.as_str()).unwrap_or("unknown")
+            response
+                .payload
+                .get("message")
+                .and_then(|v| v.as_str())
+                .unwrap_or("unknown")
        ));
    }

--- a/src-tauri/src/commands/export.rs
+++ b/src-tauri/src/commands/export.rs
@@ -33,7 +33,11 @@ pub fn export_transcript(
    if response.msg_type == "error" {
        return Err(format!(
            "Export error: {}",
-            response.payload.get("message").and_then(|v| v.as_str()).unwrap_or("unknown")
+            response
+                .payload
+                .get("message")
+                .and_then(|v| v.as_str())
+                .unwrap_or("unknown")
        ));
    }

--- a/src-tauri/src/commands/system.rs
+++ b/src-tauri/src/commands/system.rs
@@ -22,9 +22,7 @@ pub fn llama_start(
    threads: Option<u32>,
 ) -> Result<LlamaStatus, String> {
    let config = LlamaConfig {
-        binary_path: PathBuf::from(
-            binary_path.unwrap_or_else(|| "llama-server".to_string()),
-        ),
+        binary_path: PathBuf::from(binary_path.unwrap_or_else(|| "llama-server".to_string())),
        model_path: PathBuf::from(model_path),
        port: port.unwrap_or(0),
        n_gpu_layers: n_gpu_layers.unwrap_or(0),
--- a/src-tauri/src/commands/transcribe.rs
+++ b/src-tauri/src/commands/transcribe.rs
@@ -1,4 +1,5 @@
 use serde_json::{json, Value};
+use tauri::{AppHandle, Emitter};

 use crate::sidecar::messages::IPCMessage;
 use crate::sidecar::sidecar;
@@ -32,16 +33,48 @@ pub fn transcribe_file(
    if response.msg_type == "error" {
        return Err(format!(
            "Transcription error: {}",
-            response.payload.get("message").and_then(|v| v.as_str()).unwrap_or("unknown")
+            response
+                .payload
+                .get("message")
+                .and_then(|v| v.as_str())
+                .unwrap_or("unknown")
        ));
    }

    Ok(response.payload)
 }

+/// Download and validate the diarization model via the Python sidecar.
+#[tauri::command]
+pub fn download_diarize_model(hf_token: String) -> Result<Value, String> {
+    let manager = sidecar();
+    manager.ensure_running()?;
+
+    let request_id = uuid::Uuid::new_v4().to_string();
+    let msg = IPCMessage::new(
+        &request_id,
+        "diarize.download",
+        json!({
+            "hf_token": hf_token,
+        }),
+    );
+
+    let response = manager.send_and_receive(&msg)?;
+
+    if response.msg_type == "error" {
+        return Ok(json!({
+            "ok": false,
+            "error": response.payload.get("message").and_then(|v| v.as_str()).unwrap_or("unknown"),
+        }));
+    }
+
+    Ok(json!({ "ok": true }))
+}
+
 /// Run the full transcription + diarization pipeline via the Python sidecar.
 #[tauri::command]
-pub fn run_pipeline(
+pub async fn run_pipeline(
+    app: AppHandle,
    file_path: String,
    model: Option<String>,
    device: Option<String>,
@@ -50,6 +83,7 @@ pub fn run_pipeline(
    min_speakers: Option<u32>,
    max_speakers: Option<u32>,
    skip_diarization: Option<bool>,
+    hf_token: Option<String>,
 ) -> Result<Value, String> {
    let manager = sidecar();
    manager.ensure_running()?;
@@ -68,17 +102,38 @@ pub fn run_pipeline(
            "min_speakers": min_speakers,
            "max_speakers": max_speakers,
            "skip_diarization": skip_diarization.unwrap_or(false),
+            "hf_token": hf_token,
        }),
    );

-    let response = manager.send_and_receive(&msg)?;
+    // Run the blocking sidecar I/O on a separate thread so the async runtime
+    // can deliver emitted events to the webview while processing is ongoing.
+    let app_handle = app.clone();
+    tauri::async_runtime::spawn_blocking(move || {
+        let response = manager.send_and_receive_with_progress(&msg, |msg| {
+            let event_name = match msg.msg_type.as_str() {
+                "pipeline.segment" => "pipeline-segment",
+                "pipeline.speaker_update" => "pipeline-speaker-update",
+                _ => "pipeline-progress",
+            };
+            if let Err(e) = app_handle.emit(event_name, &msg.payload) {
+                eprintln!("[sidecar-rs] Failed to emit {event_name}: {e}");
+            }
+        })?;

-    if response.msg_type == "error" {
-        return Err(format!(
-            "Pipeline error: {}",
-            response.payload.get("message").and_then(|v| v.as_str()).unwrap_or("unknown")
-        ));
-    }
+        if response.msg_type == "error" {
+            return Err(format!(
+                "Pipeline error: {}",
+                response
+                    .payload
+                    .get("message")
+                    .and_then(|v| v.as_str())
+                    .unwrap_or("unknown")
+            ));
+        }

-    Ok(response.payload)
+        Ok(response.payload)
+    })
+    .await
+    .map_err(|e| format!("Pipeline task failed: {e}"))?
 }
--- a/src-tauri/src/db/schema.rs
+++ b/src-tauri/src/db/schema.rs
@@ -96,11 +96,7 @@ pub fn create_tables(conn: &Connection) -> Result<(), DatabaseError> {
    )?;

    // Initialize schema version if empty
-    let count: i32 = conn.query_row(
-        "SELECT COUNT(*) FROM schema_version",
-        [],
-        |row| row.get(0),
-    )?;
+    let count: i32 = conn.query_row("SELECT COUNT(*) FROM schema_version", [], |row| row.get(0))?;
    if count == 0 {
        conn.execute(
            "INSERT INTO schema_version (version) VALUES (?1)",
--- a/src-tauri/src/lib.rs
+++ b/src-tauri/src/lib.rs
@@ -4,12 +4,15 @@ pub mod llama;
 pub mod sidecar;
 pub mod state;

+use tauri::window::Color;
+use tauri::Manager;
+
 use commands::ai::{ai_chat, ai_configure, ai_list_providers};
 use commands::export::export_transcript;
 use commands::project::{create_project, get_project, list_projects};
 use commands::settings::{load_settings, save_settings};
 use commands::system::{get_data_dir, llama_list_models, llama_start, llama_status, llama_stop};
-use commands::transcribe::{run_pipeline, transcribe_file};
+use commands::transcribe::{download_diarize_model, run_pipeline, transcribe_file};
 use state::AppState;

 #[cfg_attr(mobile, tauri::mobile_entry_point)]
@@ -20,12 +23,20 @@ pub fn run() {
        .plugin(tauri_plugin_opener::init())
        .plugin(tauri_plugin_dialog::init())
        .manage(app_state)
+        .setup(|app| {
+            // Set the webview background to match the app's dark theme
+            if let Some(window) = app.get_webview_window("main") {
+                let _ = window.set_background_color(Some(Color(10, 10, 35, 255)));
+            }
+            Ok(())
+        })
        .invoke_handler(tauri::generate_handler![
            create_project,
            get_project,
            list_projects,
            transcribe_file,
            run_pipeline,
+            download_diarize_model,
            export_transcript,
            ai_chat,
            ai_list_providers,
--- a/src-tauri/src/llama/mod.rs
+++ b/src-tauri/src/llama/mod.rs
@@ -237,11 +237,7 @@ impl LlamaManager {

    /// Get the current status.
    pub fn status(&self) -> LlamaStatus {
-        let running = self
-            .process
-            .lock()
-            .ok()
-            .map_or(false, |p| p.is_some());
+        let running = self.process.lock().ok().map_or(false, |p| p.is_some());
        let port = self.port.lock().ok().map_or(0, |p| *p);
        let model = self
            .model_path
--- a/src-tauri/src/sidecar/mod.rs
+++ b/src-tauri/src/sidecar/mod.rs
@@ -13,8 +13,13 @@ pub fn sidecar() -> &'static SidecarManager {
    INSTANCE.get_or_init(SidecarManager::new)
 }

-/// Manages the Python sidecar process lifecycle.
-/// Uses separated stdin/stdout ownership to avoid BufReader conflicts.
+/// Manages the sidecar process lifecycle.
+///
+/// Supports two modes:
+/// - **Production**: spawns a frozen PyInstaller binary (no Python required)
+/// - **Dev mode**: spawns system Python with `-m voice_to_notes.main`
+///
+/// Dev mode is active when compiled in debug mode or when `VOICE_TO_NOTES_DEV=1`.
 pub struct SidecarManager {
    process: Mutex<Option<Child>>,
    stdin: Mutex<Option<ChildStdin>>,
@@ -30,38 +35,141 @@ impl SidecarManager {
        }
    }

+    /// Check if we should use dev mode (system Python).
+    fn is_dev_mode() -> bool {
+        cfg!(debug_assertions) || std::env::var("VOICE_TO_NOTES_DEV").is_ok()
+    }
+
+    /// Resolve the frozen sidecar binary path (production mode).
+    fn resolve_sidecar_path() -> Result<std::path::PathBuf, String> {
+        let exe = std::env::current_exe().map_err(|e| format!("Cannot get current exe: {e}"))?;
+        let exe_dir = exe
+            .parent()
+            .ok_or_else(|| "Cannot get exe parent directory".to_string())?;
+
+        let binary_name = if cfg!(target_os = "windows") {
+            "voice-to-notes-sidecar.exe"
+        } else {
+            "voice-to-notes-sidecar"
+        };
+
+        // Tauri places externalBin next to the app binary
+        let path = exe_dir.join(binary_name);
+        if path.exists() {
+            return Ok(path);
+        }
+
+        // Also check inside a subdirectory (onedir PyInstaller output)
+        let subdir_path = exe_dir.join("voice-to-notes-sidecar").join(binary_name);
+        if subdir_path.exists() {
+            return Ok(subdir_path);
+        }
+
+        Err(format!(
+            "Sidecar binary not found. Looked for:\n  {}\n  {}",
+            path.display(),
+            subdir_path.display(),
+        ))
+    }
+
+    /// Find a working Python command for the current platform.
+    fn find_python_command() -> &'static str {
+        if cfg!(target_os = "windows") {
+            "python"
+        } else {
+            "python3"
+        }
+    }
+
+    /// Resolve the Python sidecar directory for dev mode.
+    fn resolve_python_dir() -> Result<std::path::PathBuf, String> {
+        let manifest_dir = env!("CARGO_MANIFEST_DIR");
+        let python_dir = std::path::Path::new(manifest_dir)
+            .join("../python")
+            .canonicalize()
+            .map_err(|e| format!("Cannot find python directory: {e}"))?;
+
+        if python_dir.exists() {
+            return Ok(python_dir);
+        }
+
+        // Fallback: relative to current exe
+        let exe = std::env::current_exe().map_err(|e| e.to_string())?;
+        let alt = exe
+            .parent()
+            .ok_or_else(|| "No parent dir".to_string())?
+            .join("../python")
+            .canonicalize()
+            .map_err(|e| format!("Cannot find python directory: {e}"))?;
+
+        Ok(alt)
+    }
+
    /// Ensure the sidecar is running, starting it if needed.
    pub fn ensure_running(&self) -> Result<(), String> {
        if self.is_running() {
            return Ok(());
        }

-        let python_path = std::env::current_dir()
-            .map_err(|e| e.to_string())?
-            .join("../python")
-            .canonicalize()
-            .map_err(|e| format!("Cannot find python directory: {e}"))?;
-
-        self.start(&python_path.to_string_lossy())
+        if Self::is_dev_mode() {
+            self.start_python_dev()
+        } else {
+            match Self::resolve_sidecar_path() {
+                Ok(path) => self.start_binary(&path),
+                Err(e) => {
+                    eprintln!(
+                        "[sidecar-rs] Frozen binary not found ({e}), falling back to dev mode"
+                    );
+                    self.start_python_dev()
+                }
+            }
+        }
    }

-    /// Spawn the Python sidecar process.
-    pub fn start(&self, python_path: &str) -> Result<(), String> {
-        // Stop existing process if any
+    /// Spawn the frozen sidecar binary (production mode).
+    fn start_binary(&self, path: &std::path::Path) -> Result<(), String> {
        self.stop().ok();
+        eprintln!("[sidecar-rs] Starting frozen sidecar: {}", path.display());

-        let mut child = Command::new("python3")
-            .arg("-m")
-            .arg("voice_to_notes.main")
-            .current_dir(python_path)
-            .env("PYTHONPATH", python_path)
+        let child = Command::new(path)
            .stdin(Stdio::piped())
            .stdout(Stdio::piped())
            .stderr(Stdio::inherit())
            .spawn()
-            .map_err(|e| format!("Failed to start sidecar: {e}"))?;
+            .map_err(|e| format!("Failed to start sidecar binary: {e}"))?;

-        // Take ownership of stdin and stdout separately
+        self.attach(child)?;
+        self.wait_for_ready()
+    }
+
+    /// Spawn the Python sidecar in dev mode (system Python).
+    fn start_python_dev(&self) -> Result<(), String> {
+        self.stop().ok();
+        let python_dir = Self::resolve_python_dir()?;
+        let python_cmd = Self::find_python_command();
+        eprintln!(
+            "[sidecar-rs] Starting dev sidecar: {} -m voice_to_notes.main ({})",
+            python_cmd,
+            python_dir.display()
+        );
+
+        let child = Command::new(python_cmd)
+            .arg("-m")
+            .arg("voice_to_notes.main")
+            .current_dir(&python_dir)
+            .env("PYTHONPATH", &python_dir)
+            .stdin(Stdio::piped())
+            .stdout(Stdio::piped())
+            .stderr(Stdio::inherit())
+            .spawn()
+            .map_err(|e| format!("Failed to start Python sidecar: {e}"))?;
+
+        self.attach(child)?;
+        self.wait_for_ready()
+    }
+
+    /// Take ownership of a spawned child's stdin/stdout and store the process handle.
+    fn attach(&self, mut child: Child) -> Result<(), String> {
        let stdin = child.stdin.take().ok_or("Failed to get sidecar stdin")?;
        let stdout = child.stdout.take().ok_or("Failed to get sidecar stdout")?;
        let buf_reader = BufReader::new(stdout);
@@ -78,10 +186,6 @@ impl SidecarManager {
            let mut r = self.reader.lock().map_err(|e| e.to_string())?;
            *r = Some(buf_reader);
        }
-
-        // Wait for the "ready" message
-        self.wait_for_ready()?;
-
        Ok(())
    }

@@ -107,16 +211,33 @@ impl SidecarManager {
                        return Ok(());
                    }
                }
-                // Non-ready message: something is wrong
-                break;
+                // Non-JSON or non-ready line — skip and keep waiting
+                eprintln!(
+                    "[sidecar-rs] Skipping pre-ready line: {}",
+                    &trimmed[..trimmed.len().min(200)]
+                );
+                continue;
            }
        }
        Err("Sidecar did not send ready message".to_string())
    }

    /// Send a message to the sidecar and read the response.
-    /// This is a blocking call.
+    /// This is a blocking call. Progress messages are skipped.
    pub fn send_and_receive(&self, msg: &IPCMessage) -> Result<IPCMessage, String> {
+        self.send_and_receive_with_progress(msg, |_| {})
+    }
+
+    /// Send a message and receive the response, calling a callback for intermediate messages.
+    /// Intermediate messages include progress, pipeline.segment, and pipeline.speaker_update.
+    pub fn send_and_receive_with_progress<F>(
+        &self,
+        msg: &IPCMessage,
+        on_intermediate: F,
+    ) -> Result<IPCMessage, String>
+    where
+        F: Fn(&IPCMessage),
+    {
        // Write to stdin
        {
            let mut stdin_guard = self.stdin.lock().map_err(|e| e.to_string())?;
@@ -151,11 +272,17 @@ impl SidecarManager {
                    if trimmed.is_empty() {
                        continue;
                    }
-                    let response: IPCMessage = serde_json::from_str(trimmed)
-                        .map_err(|e| format!("Parse error: {e}"))?;
+                    let response: IPCMessage =
+                        serde_json::from_str(trimmed).map_err(|e| format!("Parse error: {e}"))?;

-                    // Skip progress messages, return the final result/error
-                    if response.msg_type != "progress" {
+                    // Forward intermediate messages via callback, return the final result/error
+                    let is_intermediate = matches!(
+                        response.msg_type.as_str(),
+                        "progress" | "pipeline.segment" | "pipeline.speaker_update"
+                    );
+                    if is_intermediate {
+                        on_intermediate(&response);
+                    } else {
                        return Ok(response);
                    }
                }
--- a/src-tauri/src/state.rs
+++ b/src-tauri/src/state.rs
@@ -15,12 +15,10 @@ pub struct AppState {
 impl AppState {
    pub fn new() -> Result<Self, String> {
        let data_dir = LlamaManager::data_dir();
-        std::fs::create_dir_all(&data_dir)
-            .map_err(|e| format!("Cannot create data dir: {e}"))?;
+        std::fs::create_dir_all(&data_dir).map_err(|e| format!("Cannot create data dir: {e}"))?;

        let db_path = data_dir.join("voice_to_notes.db");
-        let conn = db::open_database(&db_path)
-            .map_err(|e| format!("Cannot open database: {e}"))?;
+        let conn = db::open_database(&db_path).map_err(|e| format!("Cannot open database: {e}"))?;

        Ok(Self {
            db: Mutex::new(conn),
--- a/src-tauri/tauri.conf.json
+++ b/src-tauri/tauri.conf.json
@@ -16,7 +16,9 @@
        "width": 1200,
        "height": 800,
        "minWidth": 800,
-        "minHeight": 600
+        "minHeight": 600,
+        "decorations": true,
+        "transparent": false
      }
    ],
    "security": {
@@ -44,7 +46,7 @@
    "license": "MIT",
    "linux": {
      "deb": {
-        "depends": ["python3", "python3-pip"]
+        "depends": []
      },
      "appimage": {
        "bundleMediaFramework": true
--- a/src/app.html
+++ b/src/app.html
@@ -1,5 +1,5 @@
 <!doctype html>
-<html lang="en">
+<html lang="en" style="margin:0;padding:0;background:#0a0a23;height:100%;">
  <head>
    <meta charset="utf-8" />
    <link rel="icon" href="%sveltekit.assets%/favicon.png" />
@@ -7,7 +7,7 @@
    <title>Voice to Notes</title>
    %sveltekit.head%
  </head>
-  <body data-sveltekit-preload-data="hover">
+  <body data-sveltekit-preload-data="hover" style="margin:0;padding:0;background:#0a0a23;overflow:hidden;">
    <div style="display: contents">%sveltekit.body%</div>
  </body>
 </html>
--- a/src/lib/components/AIChatPanel.svelte
+++ b/src/lib/components/AIChatPanel.svelte
@@ -1,6 +1,7 @@
 <script lang="ts">
  import { invoke } from '@tauri-apps/api/core';
  import { segments, speakers } from '$lib/stores/transcript';
+  import { settings } from '$lib/stores/settings';

  interface ChatMessage {
    role: 'user' | 'assistant';
@@ -43,9 +44,23 @@
        content: m.content,
      }));

+      // Ensure the provider is configured with current credentials before chatting
+      const s = $settings;
+      const configMap: Record<string, Record<string, string>> = {
+        openai: { api_key: s.openai_api_key, model: s.openai_model },
+        anthropic: { api_key: s.anthropic_api_key, model: s.anthropic_model },
+        litellm: { api_key: s.litellm_api_key, api_base: s.litellm_api_base, model: s.litellm_model },
+        local: { model: s.local_model_path, base_url: 'http://localhost:8080' },
+      };
+      const config = configMap[s.ai_provider];
+      if (config) {
+        await invoke('ai_configure', { provider: s.ai_provider, config });
+      }
+
      const result = await invoke<{ response: string }>('ai_chat', {
        messages: chatMessages,
        transcriptContext: getTranscriptContext(),
+        provider: s.ai_provider,
      });

      messages = [...messages, { role: 'assistant', content: result.response }];
--- a/src/lib/components/ProgressOverlay.svelte
+++ b/src/lib/components/ProgressOverlay.svelte
@@ -7,16 +7,88 @@
  }

  let { visible = false, percent = 0, stage = '', message = '' }: Props = $props();
+
+  // Pipeline steps in order
+  const pipelineSteps = [
+    { key: 'loading_model', label: 'Load transcription model' },
+    { key: 'transcribing', label: 'Transcribe audio' },
+    { key: 'loading_diarization', label: 'Load speaker detection model' },
+    { key: 'diarizing', label: 'Identify speakers' },
+    { key: 'merging', label: 'Merge results' },
+  ];
+
+  const stepOrder = pipelineSteps.map(s => s.key);
+
+  // Track the highest step index we've reached (never goes backward)
+  let highestStepIdx = $state(-1);
+
+  // Map non-step stages to step indices for progress tracking
+  function stageToStepIdx(s: string): number {
+    const direct = stepOrder.indexOf(s);
+    if (direct >= 0) return direct;
+    // 'pipeline' stage appears before known steps — don't change highwater mark
+    return -1;
+  }
+
+  $effect(() => {
+    if (!visible) {
+      highestStepIdx = -1;
+      return;
+    }
+    const idx = stageToStepIdx(stage);
+    if (idx > highestStepIdx) {
+      highestStepIdx = idx;
+    }
+  });
+
+  function getStepStatus(stepIdx: number): 'pending' | 'active' | 'done' {
+    if (stepIdx < highestStepIdx) return 'done';
+    if (stepIdx === highestStepIdx) return 'active';
+    return 'pending';
+  }
+
+  // User-friendly display of current stage
+  const stageLabels: Record<string, string> = {
+    'pipeline': 'Initializing...',
+    'loading_model': 'Loading Model',
+    'transcribing': 'Transcribing',
+    'loading_diarization': 'Loading Diarization',
+    'diarizing': 'Speaker Detection',
+    'merging': 'Merging Results',
+    'done': 'Complete',
+  };
+
+  let displayStage = $derived(stageLabels[stage] || stage || 'Processing...');
 </script>

 {#if visible}
  <div class="overlay">
    <div class="progress-card">
-      <h3>{stage}</h3>
-      <div class="bar-track">
-        <div class="bar-fill" style="width: {percent}%"></div>
+      <div class="spinner-row">
+        <div class="spinner"></div>
+        <h3>{displayStage}</h3>
      </div>
-      <p>{percent}% — {message}</p>
+
+      <div class="steps">
+        {#each pipelineSteps as step, idx}
+          {@const status = getStepStatus(idx)}
+          <div class="step" class:step-done={status === 'done'} class:step-active={status === 'active'}>
+            <span class="step-icon">
+              {#if status === 'done'}
+                ✓
+              {:else if status === 'active'}
+                ⟳
+              {:else}
+                ·
+              {/if}
+            </span>
+            <span class="step-label">{step.label}</span>
+          </div>
+        {/each}
+      </div>
+
+      <p class="status-text">{message || 'Please wait...'}</p>
+      <p class="hint-text">This may take several minutes for large files</p>
    </div>
  </div>
 {/if}
@@ -25,34 +97,81 @@
  .overlay {
    position: fixed;
    inset: 0;
-    background: rgba(0, 0, 0, 0.7);
+    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
-    z-index: 1000;
+    z-index: 9999;
  }
  .progress-card {
    background: #16213e;
-    padding: 2rem;
+    padding: 2rem 2.5rem;
    border-radius: 12px;
-    min-width: 400px;
+    min-width: 380px;
+    max-width: 440px;
    color: #e0e0e0;
+    border: 1px solid #2a3a5e;
+    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
  }
-  h3 { margin: 0 0 1rem; text-transform: capitalize; }
-  .bar-track {
-    height: 8px;
-    background: #0f3460;
-    border-radius: 4px;
-    overflow: hidden;
+  .spinner-row {
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+    margin-bottom: 1.25rem;
  }
-  .bar-fill {
-    height: 100%;
-    background: #e94560;
-    transition: width 0.3s;
+  .spinner {
+    width: 20px;
+    height: 20px;
+    border: 3px solid #2a3a5e;
+    border-top-color: #e94560;
+    border-radius: 50%;
+    animation: spin 0.8s linear infinite;
+    flex-shrink: 0;
  }
-  p {
+  @keyframes spin {
+    to { transform: rotate(360deg); }
+  }
+  h3 {
+    margin: 0;
+    font-size: 1.1rem;
+  }
+  .steps {
+    display: flex;
+    flex-direction: column;
+    gap: 0.4rem;
+    margin-bottom: 1rem;
+  }
+  .step {
+    display: flex;
+    align-items: center;
+    gap: 0.5rem;
+    font-size: 0.85rem;
+    color: #555;
+  }
+  .step-done {
+    color: #4ecdc4;
+  }
+  .step-active {
+    color: #e0e0e0;
+    font-weight: 500;
+  }
+  .step-icon {
+    width: 1.2rem;
+    text-align: center;
+    flex-shrink: 0;
+  }
+  .step-active .step-icon {
+    animation: spin 1.5s linear infinite;
+    display: inline-block;
+  }
+  .status-text {
+    margin: 0.75rem 0 0;
+    font-size: 0.85rem;
+    color: #b0b0b0;
+  }
+  .hint-text {
    margin: 0.5rem 0 0;
-    font-size: 0.875rem;
-    color: #999;
+    font-size: 0.75rem;
+    color: #555;
  }
 </style>
--- a/src/lib/components/SettingsModal.svelte
+++ b/src/lib/components/SettingsModal.svelte
@@ -1,4 +1,6 @@
 <script lang="ts">
+  import { invoke } from '@tauri-apps/api/core';
+  import { openUrl } from '@tauri-apps/plugin-opener';
  import { settings, saveSettings, type AppSettings } from '$lib/stores/settings';

  interface Props {
@@ -9,7 +11,34 @@
  let { visible, onClose }: Props = $props();

  let localSettings = $state<AppSettings>({ ...$settings });
-  let activeTab = $state<'transcription' | 'ai' | 'local'>('transcription');
+  let activeTab = $state<'transcription' | 'speakers' | 'ai' | 'local'>('transcription');
+  let modelStatus = $state<'idle' | 'downloading' | 'success' | 'error'>('idle');
+  let modelError = $state('');
+  let revealedFields = $state<Set<string>>(new Set());
+
+  async function testAndDownloadModel() {
+    if (!localSettings.hf_token) {
+      modelStatus = 'error';
+      modelError = 'Please enter a HuggingFace token first.';
+      return;
+    }
+    modelStatus = 'downloading';
+    modelError = '';
+    try {
+      const result = await invoke<{ ok: boolean; error?: string }>('download_diarize_model', {
+        hfToken: localSettings.hf_token,
+      });
+      if (result.ok) {
+        modelStatus = 'success';
+      } else {
+        modelStatus = 'error';
+        modelError = result.error || 'Unknown error';
+      }
+    } catch (err) {
+      modelStatus = 'error';
+      modelError = String(err);
+    }
+  }

  // Sync when settings store changes
  $effect(() => {
@@ -46,6 +75,9 @@
        <button class="tab" class:active={activeTab === 'transcription'} onclick={() => activeTab = 'transcription'}>
          Transcription
        </button>
+        <button class="tab" class:active={activeTab === 'speakers'} onclick={() => activeTab = 'speakers'}>
+          Speakers
+        </button>
        <button class="tab" class:active={activeTab === 'ai'} onclick={() => activeTab = 'ai'}>
          AI Provider
        </button>
@@ -77,10 +109,72 @@
            <label for="stt-lang">Language (blank = auto-detect)</label>
            <input id="stt-lang" type="text" bind:value={localSettings.transcription_language} placeholder="e.g., en, es, fr" />
          </div>
-          <div class="field checkbox">
+        {:else if activeTab === 'speakers'}
+          <div class="field">
+            <label for="hf-token">HuggingFace Token</label>
+            <div class="input-reveal">
+              <input id="hf-token" type={revealedFields.has('hf-token') ? 'text' : 'password'} bind:value={localSettings.hf_token} placeholder="hf_..." />
+              <button type="button" class="reveal-btn" onclick={() => { const s = new Set(revealedFields); s.has('hf-token') ? s.delete('hf-token') : s.add('hf-token'); revealedFields = s; }}>{revealedFields.has('hf-token') ? 'Hide' : 'Show'}</button>
+            </div>
+          </div>
+          <div class="info-box">
+            <p class="info-title">Setup (one-time)</p>
+            <p>Speaker detection uses <strong>pyannote.audio</strong> models hosted on HuggingFace. You must accept the license for each model:</p>
+            <ol>
+              <li>Create a free account at <!-- svelte-ignore a11y_no_static_element_interactions --><a class="ext-link" onclick={() => openUrl('https://huggingface.co/join')}>huggingface.co</a></li>
+              <li>Accept the license on <strong>all three</strong> of these pages:
+                <ul>
+                  <!-- svelte-ignore a11y_no_static_element_interactions -->
+                  <li><a class="ext-link" onclick={() => openUrl('https://huggingface.co/pyannote/speaker-diarization-3.1')}>pyannote/speaker-diarization-3.1</a></li>
+                  <!-- svelte-ignore a11y_no_static_element_interactions -->
+                  <li><a class="ext-link" onclick={() => openUrl('https://huggingface.co/pyannote/segmentation-3.0')}>pyannote/segmentation-3.0</a></li>
+                  <!-- svelte-ignore a11y_no_static_element_interactions -->
+                  <li><a class="ext-link" onclick={() => openUrl('https://huggingface.co/pyannote/speaker-diarization-community-1')}>pyannote/speaker-diarization-community-1</a></li>
+                </ul>
+              </li>
+              <!-- svelte-ignore a11y_no_static_element_interactions -->
+              <li>Create a token at <a class="ext-link" onclick={() => openUrl('https://huggingface.co/settings/tokens')}>huggingface.co/settings/tokens</a> (read access)</li>
+              <li>Paste the token above and click <strong>Test & Download</strong></li>
+            </ol>
+          </div>
+          <button
+            class="btn-download"
+            onclick={testAndDownloadModel}
+            disabled={modelStatus === 'downloading'}
+          >
+            {#if modelStatus === 'downloading'}
+              Downloading model...
+            {:else}
+              Test & Download Model
+            {/if}
+          </button>
+          {#if modelStatus === 'success'}
+            <p class="status-success">Model downloaded successfully. Speaker detection is ready.</p>
+          {/if}
+          {#if modelStatus === 'error'}
+            <p class="status-error">{modelError}</p>
+          {/if}
+          <div class="field" style="margin-top: 1rem;">
+            <label for="num-speakers">Number of speakers</label>
+            <select
+              id="num-speakers"
+              value={localSettings.num_speakers === null || localSettings.num_speakers === 0 ? '0' : String(localSettings.num_speakers)}
+              onchange={(e) => {
+                const v = parseInt((e.target as HTMLSelectElement).value, 10);
+                localSettings.num_speakers = v === 0 ? null : v;
+              }}
+            >
+              <option value="0">Auto-detect</option>
+              {#each Array.from({ length: 20 }, (_, i) => i + 1) as n}
+                <option value={String(n)}>{n}</option>
+              {/each}
+            </select>
+            <p class="hint">Hint the expected number of speakers to speed up diarization clustering.</p>
+          </div>
+          <div class="field checkbox" style="margin-top: 1rem;">
            <label>
              <input type="checkbox" bind:checked={localSettings.skip_diarization} />
-              Skip speaker diarization (faster, no speaker labels)
+              Skip speaker detection (faster, no speaker labels)
            </label>
          </div>
        {:else if activeTab === 'ai'}
@@ -90,14 +184,17 @@
              <option value="local">Local (llama-server)</option>
              <option value="openai">OpenAI</option>
              <option value="anthropic">Anthropic</option>
-              <option value="litellm">LiteLLM</option>
+              <option value="litellm">OpenAI Compatible</option>
            </select>
          </div>

          {#if localSettings.ai_provider === 'openai'}
            <div class="field">
              <label for="openai-key">OpenAI API Key</label>
-              <input id="openai-key" type="password" bind:value={localSettings.openai_api_key} placeholder="sk-..." />
+              <div class="input-reveal">
+                <input id="openai-key" type={revealedFields.has('openai-key') ? 'text' : 'password'} bind:value={localSettings.openai_api_key} placeholder="sk-..." />
+                <button type="button" class="reveal-btn" onclick={() => { const s = new Set(revealedFields); s.has('openai-key') ? s.delete('openai-key') : s.add('openai-key'); revealedFields = s; }}>{revealedFields.has('openai-key') ? 'Hide' : 'Show'}</button>
+              </div>
            </div>
            <div class="field">
              <label for="openai-model">Model</label>
@@ -106,13 +203,27 @@
          {:else if localSettings.ai_provider === 'anthropic'}
            <div class="field">
              <label for="anthropic-key">Anthropic API Key</label>
-              <input id="anthropic-key" type="password" bind:value={localSettings.anthropic_api_key} placeholder="sk-ant-..." />
+              <div class="input-reveal">
+                <input id="anthropic-key" type={revealedFields.has('anthropic-key') ? 'text' : 'password'} bind:value={localSettings.anthropic_api_key} placeholder="sk-ant-..." />
+                <button type="button" class="reveal-btn" onclick={() => { const s = new Set(revealedFields); s.has('anthropic-key') ? s.delete('anthropic-key') : s.add('anthropic-key'); revealedFields = s; }}>{revealedFields.has('anthropic-key') ? 'Hide' : 'Show'}</button>
+              </div>
            </div>
            <div class="field">
              <label for="anthropic-model">Model</label>
              <input id="anthropic-model" type="text" bind:value={localSettings.anthropic_model} />
            </div>
          {:else if localSettings.ai_provider === 'litellm'}
+            <div class="field">
+              <label for="litellm-base">API Base URL</label>
+              <input id="litellm-base" type="text" bind:value={localSettings.litellm_api_base} placeholder="https://your-litellm-proxy.example.com" />
+            </div>
+            <div class="field">
+              <label for="litellm-key">API Key</label>
+              <div class="input-reveal">
+                <input id="litellm-key" type={revealedFields.has('litellm-key') ? 'text' : 'password'} bind:value={localSettings.litellm_api_key} placeholder="sk-..." />
+                <button type="button" class="reveal-btn" onclick={() => { const s = new Set(revealedFields); s.has('litellm-key') ? s.delete('litellm-key') : s.add('litellm-key'); revealedFields = s; }}>{revealedFields.has('litellm-key') ? 'Hide' : 'Show'}</button>
+              </div>
+            </div>
            <div class="field">
              <label for="litellm-model">Model</label>
              <input id="litellm-model" type="text" bind:value={localSettings.litellm_model} placeholder="provider/model-name" />
@@ -220,11 +331,36 @@
    color: #aaa;
    margin-bottom: 0.3rem;
  }
+  .input-reveal {
+    display: flex;
+    gap: 0;
+  }
+  .input-reveal input {
+    flex: 1;
+    border-top-right-radius: 0;
+    border-bottom-right-radius: 0;
+  }
+  .reveal-btn {
+    background: #0f3460;
+    border: 1px solid #4a5568;
+    border-left: none;
+    color: #aaa;
+    padding: 0.5rem 0.6rem;
+    border-radius: 0 4px 4px 0;
+    cursor: pointer;
+    font-size: 0.75rem;
+    white-space: nowrap;
+  }
+  .reveal-btn:hover {
+    color: #e0e0e0;
+    background: #1a4a7a;
+  }
  .field input,
  .field select {
    width: 100%;
    background: #1a1a2e;
    color: #e0e0e0;
+    color-scheme: dark;
    border: 1px solid #4a5568;
    border-radius: 4px;
    padding: 0.5rem;
@@ -252,6 +388,79 @@
    color: #666;
    line-height: 1.4;
  }
+  .info-box {
+    background: rgba(233, 69, 96, 0.05);
+    border: 1px solid #2a3a5e;
+    border-radius: 6px;
+    padding: 0.75rem 1rem;
+    margin-bottom: 1rem;
+    font-size: 0.8rem;
+    color: #b0b0b0;
+    line-height: 1.5;
+  }
+  .info-box p {
+    margin: 0 0 0.5rem;
+  }
+  .info-box p:last-child {
+    margin-bottom: 0;
+  }
+  .info-box .info-title {
+    color: #e0e0e0;
+    font-weight: 600;
+    font-size: 0.8rem;
+  }
+  .info-box ol {
+    margin: 0.25rem 0 0.5rem;
+    padding-left: 1.25rem;
+  }
+  .info-box li {
+    margin-bottom: 0.25rem;
+  }
+  .info-box strong {
+    color: #e0e0e0;
+  }
+  .ext-link {
+    color: #e94560;
+    cursor: pointer;
+    text-decoration: underline;
+  }
+  .ext-link:hover {
+    color: #ff6b81;
+  }
+  .info-box ul {
+    margin: 0.25rem 0;
+    padding-left: 1.25rem;
+  }
+  .btn-download {
+    background: #0f3460;
+    border: 1px solid #4a5568;
+    color: #e0e0e0;
+    padding: 0.5rem 1rem;
+    border-radius: 6px;
+    cursor: pointer;
+    font-size: 0.85rem;
+    width: 100%;
+    margin-bottom: 0.5rem;
+  }
+  .btn-download:hover:not(:disabled) {
+    background: #1a4a7a;
+    border-color: #e94560;
+  }
+  .btn-download:disabled {
+    opacity: 0.6;
+    cursor: not-allowed;
+  }
+  .status-success {
+    color: #4ecdc4;
+    font-size: 0.8rem;
+    margin: 0.25rem 0;
+  }
+  .status-error {
+    color: #e94560;
+    font-size: 0.8rem;
+    margin: 0.25rem 0;
+    word-break: break-word;
+  }
  .modal-footer {
    display: flex;
    justify-content: flex-end;
--- a/src/lib/components/SpeakerManager.svelte
+++ b/src/lib/components/SpeakerManager.svelte
@@ -1,5 +1,6 @@
 <script lang="ts">
  import { speakers } from '$lib/stores/transcript';
+  import { settings } from '$lib/stores/settings';
  import type { Speaker } from '$lib/types/transcript';

  let editingSpeakerId = $state<string | null>(null);
@@ -34,7 +35,14 @@
 <div class="speaker-manager">
  <h3>Speakers</h3>
  {#if $speakers.length === 0}
-    <p class="empty-hint">No speakers detected yet</p>
+    <p class="empty-hint">No speakers detected</p>
+    {#if $settings.skip_diarization}
+      <p class="setup-hint">Speaker detection is disabled. Enable it in Settings &gt; Speakers.</p>
+    {:else if !$settings.hf_token}
+      <p class="setup-hint">Speaker detection requires a HuggingFace token. Configure it in Settings &gt; Speakers.</p>
+    {:else}
+      <p class="setup-hint">Speaker detection ran but found no distinct speakers, or the model may need to be downloaded. Check Settings &gt; Speakers.</p>
+    {/if}
  {:else}
    <ul class="speaker-list">
      {#each $speakers as speaker (speaker.id)}
@@ -78,6 +86,19 @@
  .empty-hint {
    color: #666;
    font-size: 0.875rem;
+    margin-bottom: 0.25rem;
+  }
+  .setup-hint {
+    color: #555;
+    font-size: 0.75rem;
+    line-height: 1.4;
+  }
+  .setup-hint code {
+    background: rgba(233, 69, 96, 0.15);
+    color: #e94560;
+    padding: 0.1rem 0.3rem;
+    border-radius: 3px;
+    font-size: 0.7rem;
  }
  .speaker-list {
    list-style: none;
--- a/src/lib/components/TranscriptEditor.svelte
+++ b/src/lib/components/TranscriptEditor.svelte
@@ -217,6 +217,8 @@
  .segment-text {
    line-height: 1.6;
    padding-left: 0.75rem;
+    word-wrap: break-word;
+    overflow-wrap: break-word;
  }
  .word {
    cursor: pointer;
--- a/src/lib/components/WaveformPlayer.svelte
+++ b/src/lib/components/WaveformPlayer.svelte
@@ -12,6 +12,8 @@

  let container: HTMLDivElement;
  let wavesurfer: WaveSurfer | null = $state(null);
+  let isReady = $state(false);
+  let isLoading = $state(false);
  let currentTime = $state('0:00');
  let totalTime = $state('0:00');

@@ -31,6 +33,7 @@
      barWidth: 2,
      barGap: 1,
      barRadius: 2,
+      backend: 'WebAudio',
    });

    wavesurfer.on('timeupdate', (time: number) => {
@@ -39,6 +42,8 @@
    });

    wavesurfer.on('ready', () => {
+      isReady = true;
+      isLoading = false;
      const dur = wavesurfer!.getDuration();
      durationMs.set(Math.round(dur * 1000));
      totalTime = formatTime(dur);
@@ -48,8 +53,12 @@
    wavesurfer.on('pause', () => isPlaying.set(false));
    wavesurfer.on('finish', () => isPlaying.set(false));

+    wavesurfer.on('loading', () => {
+      isReady = false;
+    });
+
    if (audioUrl) {
-      wavesurfer.load(audioUrl);
+      loadAudio(audioUrl);
    }
  });

@@ -57,20 +66,21 @@
    wavesurfer?.destroy();
  });

-  /** Toggle play/pause. Exposed for keyboard shortcuts. */
+  /** Toggle play/pause from current position. Exposed for keyboard shortcuts. */
  export function togglePlayPause() {
-    wavesurfer?.playPause();
+    if (!wavesurfer || !isReady) return;
+    wavesurfer.playPause();
  }

  function skipBack() {
-    if (wavesurfer) {
+    if (wavesurfer && isReady) {
      const time = Math.max(0, wavesurfer.getCurrentTime() - 5);
      wavesurfer.setTime(time);
    }
  }

  function skipForward() {
-    if (wavesurfer) {
+    if (wavesurfer && isReady) {
      const time = Math.min(wavesurfer.getDuration(), wavesurfer.getCurrentTime() + 5);
      wavesurfer.setTime(time);
    }
@@ -78,16 +88,17 @@

  /** Seek to a specific time in milliseconds. Called from transcript click-to-seek. */
  export function seekTo(timeMs: number) {
-    if (wavesurfer) {
-      wavesurfer.setTime(timeMs / 1000);
-      if (!wavesurfer.isPlaying()) {
-        wavesurfer.play();
-      }
+    if (!wavesurfer || !isReady) {
+      console.warn('[voice-to-notes] seekTo ignored — audio not ready yet');
+      return;
    }
+    wavesurfer.setTime(timeMs / 1000);
  }

  /** Load a new audio file. */
  export function loadAudio(url: string) {
+    isReady = false;
+    isLoading = true;
    wavesurfer?.load(url);
  }
 </script>
@@ -95,11 +106,17 @@
 <div class="waveform-player">
  <div class="waveform-container" bind:this={container}></div>
  <div class="controls">
-    <button class="control-btn" onclick={skipBack} title="Back 5s">⏪</button>
-    <button class="control-btn play-btn" onclick={togglePlayPause} title="Play/Pause">
-      {#if $isPlaying}⏸{:else}▶{/if}
+    <button class="control-btn" onclick={skipBack} title="Back 5s" disabled={!isReady}>⏪</button>
+    <button class="control-btn play-btn" onclick={togglePlayPause} title="Play/Pause" disabled={!isReady}>
+      {#if !isReady}
+        ⏳
+      {:else if $isPlaying}
+        ⏸
+      {:else}
+        ▶
+      {/if}
    </button>
-    <button class="control-btn" onclick={skipForward} title="Forward 5s">⏩</button>
+    <button class="control-btn" onclick={skipForward} title="Forward 5s" disabled={!isReady}>⏩</button>
    <span class="time">{currentTime} / {totalTime}</span>
  </div>
 </div>
@@ -129,9 +146,13 @@
    cursor: pointer;
    font-size: 1rem;
  }
-  .control-btn:hover {
+  .control-btn:hover:not(:disabled) {
    background: #1a4a7a;
  }
+  .control-btn:disabled {
+    opacity: 0.4;
+    cursor: not-allowed;
+  }
  .play-btn {
    padding: 0.4rem 1rem;
    font-size: 1.2rem;
--- a/src/lib/stores/settings.ts
+++ b/src/lib/stores/settings.ts
@@ -8,12 +8,16 @@ export interface AppSettings {
  openai_model: string;
  anthropic_model: string;
  litellm_model: string;
+  litellm_api_key: string;
+  litellm_api_base: string;
  local_model_path: string;
  local_binary_path: string;
  transcription_model: string;
  transcription_device: string;
  transcription_language: string;
  skip_diarization: boolean;
+  hf_token: string;
+  num_speakers: number | null;
 }

 const defaults: AppSettings = {
@@ -23,12 +27,16 @@ const defaults: AppSettings = {
  openai_model: 'gpt-4o-mini',
  anthropic_model: 'claude-sonnet-4-6',
  litellm_model: 'gpt-4o-mini',
+  litellm_api_key: '',
+  litellm_api_base: '',
  local_model_path: '',
  local_binary_path: 'llama-server',
  transcription_model: 'base',
  transcription_device: 'cpu',
  transcription_language: '',
  skip_diarization: false,
+  hf_token: '',
+  num_speakers: null,
 };

 export const settings = writable<AppSettings>({ ...defaults });
@@ -45,4 +53,20 @@ export async function loadSettings(): Promise<void> {
 export async function saveSettings(s: AppSettings): Promise<void> {
  settings.set(s);
  await invoke('save_settings', { settings: s });
+
+  // Configure the AI provider in the Python sidecar
+  const configMap: Record<string, Record<string, string>> = {
+    openai: { api_key: s.openai_api_key, model: s.openai_model },
+    anthropic: { api_key: s.anthropic_api_key, model: s.anthropic_model },
+    litellm: { api_key: s.litellm_api_key, api_base: s.litellm_api_base, model: s.litellm_model },
+    local: { model: s.local_model_path, base_url: 'http://localhost:8080' },
+  };
+  const config = configMap[s.ai_provider];
+  if (config) {
+    try {
+      await invoke('ai_configure', { provider: s.ai_provider, config });
+    } catch {
+      // Sidecar may not be running yet — provider will be configured on first use
+    }
+  }
 }
--- a/src/routes/+layout.svelte
+++ b/src/routes/+layout.svelte
@@ -10,6 +10,7 @@
    padding: 0;
    background: #0a0a23;
    color: #e0e0e0;
+    color-scheme: dark;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen,
      Ubuntu, Cantarell, sans-serif;
    overflow: hidden;
--- a/src/routes/+page.svelte
+++ b/src/routes/+page.svelte
@@ -1,5 +1,6 @@
 <script lang="ts">
  import { invoke, convertFileSrc } from '@tauri-apps/api/core';
+  import { listen } from '@tauri-apps/api/event';
  import { open, save } from '@tauri-apps/plugin-dialog';
  import WaveformPlayer from '$lib/components/WaveformPlayer.svelte';
  import TranscriptEditor from '$lib/components/TranscriptEditor.svelte';
@@ -10,8 +11,9 @@
  import { segments, speakers } from '$lib/stores/transcript';
  import { settings, loadSettings } from '$lib/stores/settings';
  import type { Segment, Speaker } from '$lib/types/transcript';
-  import { onMount } from 'svelte';
+  import { onMount, tick } from 'svelte';

+  let appReady = $state(false);
  let waveformPlayer: WaveformPlayer;
  let audioUrl = $state('');
  let showSettings = $state(false);
@@ -53,6 +55,8 @@
    document.addEventListener('keydown', handleKeyDown);
    document.addEventListener('click', handleClickOutside);

+    appReady = true;
+
    return () => {
      document.removeEventListener('keydown', handleKeyDown);
      document.removeEventListener('click', handleClickOutside);
@@ -67,6 +71,7 @@
  const speakerColors = ['#e94560', '#4ecdc4', '#ffe66d', '#a8e6cf', '#ff8b94', '#c7ceea', '#ffd93d', '#6bcb77'];

  function handleWordClick(timeMs: number) {
+    console.log('[voice-to-notes] Word clicked, seeking to', timeMs, 'ms');
    waveformPlayer?.seekTo(timeMs);
  }

@@ -85,10 +90,93 @@
    audioUrl = convertFileSrc(filePath);
    waveformPlayer?.loadAudio(audioUrl);

+    // Clear previous results
+    segments.set([]);
+    speakers.set([]);
+
    // Start pipeline (transcription + diarization)
    isTranscribing = true;
    transcriptionProgress = 0;
    transcriptionStage = 'Starting...';
+    transcriptionMessage = 'Initializing pipeline...';
+
+    // Flush DOM so the progress overlay renders before the blocking invoke
+    await tick();
+
+    // Listen for progress events from the sidecar
+    const unlisten = await listen<{
+      percent: number;
+      stage: string;
+      message: string;
+    }>('pipeline-progress', (event) => {
+      console.log('[voice-to-notes] Progress event:', event.payload);
+      const { percent, stage, message } = event.payload;
+      if (typeof percent === 'number') transcriptionProgress = percent;
+      if (typeof stage === 'string') transcriptionStage = stage;
+      if (typeof message === 'string') transcriptionMessage = message;
+    });
+
+    const unlistenSegment = await listen<{
+      index: number;
+      text: string;
+      start_ms: number;
+      end_ms: number;
+      words: Array<{ word: string; start_ms: number; end_ms: number; confidence: number }>;
+    }>('pipeline-segment', (event) => {
+      const seg = event.payload;
+      const newSeg: Segment = {
+        id: `seg-${seg.index}`,
+        project_id: '',
+        media_file_id: '',
+        speaker_id: null,
+        start_ms: seg.start_ms,
+        end_ms: seg.end_ms,
+        text: seg.text,
+        original_text: null,
+        confidence: null,
+        is_edited: false,
+        edited_at: null,
+        segment_index: seg.index,
+        words: seg.words.map((w, widx) => ({
+          id: `word-${seg.index}-${widx}`,
+          segment_id: `seg-${seg.index}`,
+          word: w.word,
+          start_ms: w.start_ms,
+          end_ms: w.end_ms,
+          confidence: w.confidence,
+          word_index: widx,
+        })),
+      };
+      segments.update(segs => [...segs, newSeg]);
+    });
+
+    const unlistenSpeaker = await listen<{
+      updates: Array<{ index: number; speaker: string }>;
+    }>('pipeline-speaker-update', (event) => {
+      const { updates } = event.payload;
+      // Build speakers from unique labels
+      const uniqueLabels = [...new Set(updates.map(u => u.speaker))].sort();
+      const newSpeakers: Speaker[] = uniqueLabels.map((label, idx) => ({
+        id: `speaker-${idx}`,
+        project_id: '',
+        label,
+        display_name: null,
+        color: speakerColors[idx % speakerColors.length],
+      }));
+      speakers.set(newSpeakers);
+
+      // Update existing segments with speaker assignments
+      const speakerLookup = new Map(newSpeakers.map(s => [s.label, s.id]));
+      segments.update(segs =>
+        segs.map((seg, i) => {
+          const update = updates.find(u => u.index === i);
+          if (update) {
+            return { ...seg, speaker_id: speakerLookup.get(update.speaker) ?? null };
+          }
+          return seg;
+        })
+      );
+    });

    try {
      const result = await invoke<{
@@ -114,6 +202,8 @@
        device: $settings.transcription_device || undefined,
        language: $settings.transcription_language || undefined,
        skipDiarization: $settings.skip_diarization || undefined,
+        hfToken: $settings.hf_token || undefined,
+        numSpeakers: $settings.num_speakers && $settings.num_speakers > 0 ? $settings.num_speakers : undefined,
      });

      // Create speaker entries from pipeline result
@@ -159,6 +249,9 @@
      console.error('Pipeline failed:', err);
      alert(`Pipeline failed: ${err}`);
    } finally {
+      unlisten();
+      unlistenSegment();
+      unlistenSpeaker();
      isTranscribing = false;
    }
  }
@@ -214,56 +307,70 @@
  }
 </script>

-<div class="app-header">
-  <h1>Voice to Notes</h1>
-  <div class="header-actions">
-    <button class="import-btn" onclick={handleFileImport}>
-      Import Audio/Video
-    </button>
-    <button class="settings-btn" onclick={() => showSettings = true} title="Settings">
-      Settings
-    </button>
-    {#if $segments.length > 0}
-      <div class="export-dropdown">
-        <button class="export-btn" onclick={() => showExportMenu = !showExportMenu}>
-          Export
-        </button>
-        {#if showExportMenu}
-          <div class="export-menu">
-            {#each exportFormats as fmt}
-              <button class="export-option" onclick={() => handleExport(fmt.format, fmt.ext, fmt.name)}>
-                {fmt.name} (.{fmt.ext})
-              </button>
-            {/each}
-          </div>
+{#if !appReady}
+  <div class="splash-screen">
+    <h1 class="splash-title">Voice to Notes</h1>
+    <p class="splash-subtitle">Loading...</p>
+    <div class="splash-spinner"></div>
+  </div>
+{:else}
+  <div class="app-shell">
+  <div class="app-header">
+    <h1>Voice to Notes</h1>
+    <div class="header-actions">
+      <button class="import-btn" onclick={handleFileImport} disabled={isTranscribing}>
+        {#if isTranscribing}
+          Processing...
+        {:else}
+          Import Audio/Video
        {/if}
-      </div>
-    {/if}
+      </button>
+      <button class="settings-btn" onclick={() => showSettings = true} title="Settings">
+        Settings
+      </button>
+      {#if $segments.length > 0}
+        <div class="export-dropdown">
+          <button class="export-btn" onclick={() => showExportMenu = !showExportMenu}>
+            Export
+          </button>
+          {#if showExportMenu}
+            <div class="export-menu">
+              {#each exportFormats as fmt}
+                <button class="export-option" onclick={() => handleExport(fmt.format, fmt.ext, fmt.name)}>
+                  {fmt.name} (.{fmt.ext})
+                </button>
+              {/each}
+            </div>
+          {/if}
+        </div>
+      {/if}
+    </div>
  </div>
-</div>

-<div class="workspace">
-  <div class="main-content">
-    <WaveformPlayer bind:this={waveformPlayer} {audioUrl} />
-    <TranscriptEditor onWordClick={handleWordClick} />
+  <div class="workspace">
+    <div class="main-content">
+      <WaveformPlayer bind:this={waveformPlayer} {audioUrl} />
+      <TranscriptEditor onWordClick={handleWordClick} />
+    </div>
+    <div class="sidebar-right">
+      <SpeakerManager />
+      <AIChatPanel />
+    </div>
  </div>
-  <div class="sidebar-right">
-    <SpeakerManager />
-    <AIChatPanel />
  </div>
-</div>

-<ProgressOverlay
-  visible={isTranscribing}
-  percent={transcriptionProgress}
-  stage={transcriptionStage}
-  message={transcriptionMessage}
-/>
+  <ProgressOverlay
+    visible={isTranscribing}
+    percent={transcriptionProgress}
+    stage={transcriptionStage}
+    message={transcriptionMessage}
+  />

-<SettingsModal
-  visible={showSettings}
-  onClose={() => showSettings = false}
-/>
+  <SettingsModal
+    visible={showSettings}
+    onClose={() => showSettings = false}
+  />
+{/if}

 <style>
  .app-header {
@@ -288,9 +395,18 @@
    font-size: 0.875rem;
    font-weight: 500;
  }
-  .import-btn:hover {
+  .import-btn:hover:not(:disabled) {
    background: #d63851;
  }
+  .import-btn:disabled {
+    opacity: 0.7;
+    cursor: not-allowed;
+    animation: pulse 1.5s ease-in-out infinite;
+  }
+  @keyframes pulse {
+    0%, 100% { opacity: 0.7; }
+    50% { opacity: 1; }
+  }
  .header-actions {
    display: flex;
    gap: 0.5rem;
@@ -351,11 +467,19 @@
  .export-option:hover {
    background: rgba(233, 69, 96, 0.2);
  }
+  .app-shell {
+    display: flex;
+    flex-direction: column;
+    height: 100vh;
+    overflow: hidden;
+  }
  .workspace {
    display: flex;
    gap: 1rem;
    padding: 1rem;
-    height: calc(100vh - 3.5rem);
+    flex: 1;
+    min-height: 0;
+    overflow: hidden;
    background: #0a0a23;
  }
  .main-content {
@@ -364,6 +488,8 @@
    flex-direction: column;
    gap: 1rem;
    min-width: 0;
+    min-height: 0;
+    overflow-y: auto;
  }
  .sidebar-right {
    width: 300px;
@@ -371,5 +497,38 @@
    flex-direction: column;
    gap: 1rem;
    flex-shrink: 0;
+    min-height: 0;
+    overflow-y: auto;
+  }
+  .splash-screen {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    height: 100vh;
+    background: #0a0a23;
+    color: #e0e0e0;
+    gap: 1rem;
+  }
+  .splash-title {
+    font-size: 2rem;
+    margin: 0;
+    color: #e94560;
+  }
+  .splash-subtitle {
+    font-size: 1rem;
+    color: #888;
+    margin: 0;
+  }
+  .splash-spinner {
+    width: 32px;
+    height: 32px;
+    border: 3px solid #2a3a5e;
+    border-top-color: #e94560;
+    border-radius: 50%;
+    animation: spin 0.8s linear infinite;
+  }
+  @keyframes spin {
+    to { transform: rotate(360deg); }
  }
 </style>