inboil

Browser-native instrument inspired by Eurorack, Elektron hardware, and Teenage Engineering OP-XY. inboil turns any device with a browser into a playable groovebox for scene-based sequencing, performance, and controlled generative composition — all running in a single AudioWorklet, zero npm runtime dependencies.

Features

• 20 voice types — 12 drum synths (incl. FM Drum with 6 machine algorithms), 2 sample drums (crash/ride), TB-303 bass, analog lead, analog bass, 4-op FM (12-voice poly), wavetable (16-voice poly), polyphonic sampler
• Audio Pool — 111 factory samples (90 browsable across 11 categories + 21 Grand Piano pack zones) stored in OPFS; inline browser with folder drill-down, search, audition; user samples auto-imported
• Variable track count (up to 16) — per-pattern, independent step counts (2–64), per-track step scale (1/8 to 1/32), polymetric
• Parameter locks (P-Lock) — per-step parameter overrides, Elektron-style
• Piano roll & tracker view — note/duration editing for melodic tracks
• Graphical Sequencer — node-based arrangement with pattern nodes, generative nodes (Turing Machine, Quantizer, Tonnetz), modifiers, sweep recording automation, and edge-based branching
• Scale-aware arpeggiator — UP / DOWN / UP-DOWN / RANDOM with diatonic chord modes
• Effects — reverb, delay, glitch, granular with XY performance pads; per-track insert FX (reverb/delay/glitch/dist); 3-band EQ; DJ filter
• Sidechain ducker & bus compressor — master bus processing with peak limiter
• 100+ factory presets — 30 WT, 20 FM, 22 FM Drum, drum & synth presets
• 100 pattern slots — 4 factory + 96 user, IndexedDB persistence
• Performance controls — fill, reverse, break, swing, key transpose, chord brush
• WAV recording — capture master output with reverb tail
• Hardware MIDI — USB + BLE MIDI input with per-note release
• Responsive — desktop grid, tablet compact, mobile calculator layout
• Bilingual — English / Japanese (help, tooltips, docs)

Tech Stack

Layer	Tech
UI	Svelte 5 (runes), TypeScript
Build	Vite 8
DSP	TypeScript AudioWorklet
Audio	AudioWorklet, Web Audio API
Docs	Astro + Starlight
Fonts	Bebas Neue, JetBrains Mono

Getting Started

pnpm install
pnpm dev

Open http://localhost:5173 in a browser that supports AudioWorklet.

Commands

pnpm dev       # Vite dev server
pnpm build     # production build
pnpm check     # svelte-check
pnpm deploy    # build + Cloudflare Pages

Project Structure

src/
├── App.svelte                  # Root component (layout, engine wiring)
├── app.css                     # Global styles (reset, design tokens)
├── lib/
│   ├── audio/
│   │   ├── engine.ts           # Main thread ↔ worklet bridge
│   │   ├── worklet-processor.ts # AudioWorklet sequencer + DSP
│   │   └── dsp/                # Voice engines, effects, filters
│   ├── components/             # Svelte 5 UI components
│   ├── multiDevice/            # WebRTC multi-device jam (ADR 019)
│   ├── types.ts                # Core data types (Song, Pattern, Cell, Trig)
│   ├── state.svelte.ts         # Reactive state ($state declarations, undo/redo)
│   ├── *Actions.ts             # Domain mutations (step, scene, section, sample, pool, project)
│   ├── importExport.ts         # JSON export/import, demo song loading
│   ├── scene*.ts               # Scene graph: actions, playback, geometry, data
│   ├── sweep*.ts               # Sweep automation: recorder, evaluator, playback
│   ├── generative.ts           # Turing Machine, Quantizer, Tonnetz engines
│   ├── storage.ts              # IndexedDB + localStorage persistence
│   └── ...                     # Presets, params, helpers, MIDI, WAV, etc.
public/samples/                 # Factory sample WebM files + manifest
site/                           # Astro docs & landing page
docs/ai/                        # Design specs & ADRs

Links

• Docs
• Support (Ko-fi)

License

AGPL-3.0