SoundBit

A chiptune workstation for humans and AI agents.

Compose 8-bit and 16-bit music in a tracker-style editor, or let an AI agent write it for you through the Model Context Protocol. Both work on the same song at the same time: what the agent writes appears in the editor as it happens, and every change can be undone.

Install · What you get · AI agents · Tools · Wiki · Changelog

What you get

• A tracker-style editor. One-bar patterns placed on tracks; a canvas arrangement view and piano roll; instruments, song settings, transport, undo and redo; five colour themes.
• Chip voices. Pulse with four duty cycles, NES-style stepped triangle, sawtooth, sine, LFSR noise (long and metallic), Game Boy-style 4-bit wavetables and 4-operator YM2612-style FM with eight algorithms.
• Sound shaping. Pitch envelopes for kicks, toms and lasers; delayed vibrato; up to four detuned unison layers for strings and choirs; a resonant low-, high- and band-pass filter that can follow the envelope; and a shared reverb room with a send per instrument.
• 32 presets. Orchestral strings, brass, choir and timpani, a drum kit, chip leads and basses, FM keys and effects, stored as plain JSON in assets/presets.
• Chip profiles. Optionally keep a song within what an NES, Game Boy, Commodore 64 or Genesis could play: track count, voice types per channel and notes at once.
• An MCP server with 30 tools. Agents create instruments, write whole patterns in one call, lay out a full arrangement in another, render to WAV and get the level of every track back, so they can balance a mix they cannot hear.
• Bit-exact audio. The same song renders to the same samples on every platform. No sound depends on your operating system's math library.

Safe by design

• Local only. The MCP endpoint listens on 127.0.0.1. Requests from other machines, from websites in your browser (any Origin header) and with foreign Host headers are refused.
• A sandbox for agents. Agents only read and write files inside one workspace folder; absolute paths, .. and symlinks out of it are rejected.
• Undo anything. Every change, yours or an agent's, is one step in the history. Agent steps are labelled AI:.
• Nothing phones home. No telemetry, no accounts, no update checks.

Install

Download the latest version from the releases page:

The builds are not code-signed yet. On Windows, SmartScreen may warn the first time: choose More info → Run anyway. On macOS, right-click the app and choose Open the first time, or run xattr -dr com.apple.quarantine /Applications/SoundBit.app.

You need a stable Rust toolchain and Node.js 22 or newer. On Linux, also install the ALSA and WebKitGTK development packages:

# Debian / Ubuntu
sudo apt-get install -y libasound2-dev libwebkit2gtk-4.1-dev libsoup-3.0-dev \
  libjavascriptcoregtk-4.1-dev librsvg2-dev libayatana-appindicator3-dev

git clone https://github.com/RenasDemirbas/SoundBit.git
cd SoundBit/apps/desktop
npm install
npm run tauri dev          # run the desktop app
npm run tauri build        # or build an installer for your platform
cargo install --path ../../crates/soundbit-cli   # the `soundbit` command

The command-line tool renders, plays and inspects projects without the editor, and runs a headless MCP server:

soundbit play examples/songs/pixel-sunrise.sbproj
soundbit render examples/songs/clash-of-banners.sbproj -o clash.wav
soundbit info examples/songs/first-light.sbproj

Compose with an AI agent

With the desktop app open, SoundBit serves MCP over streamable HTTP at http://127.0.0.1:7413/mcp (shown in the status bar; SOUNDBIT_MCP_PORT changes the port). Register it with your MCP client as an HTTP server. The agent's workspace is the SoundBit folder in your Music directory.

// Most MCP clients accept a configuration like this
"soundbit": { "type": "http", "url": "http://127.0.0.1:7413/mcp" }

Without the app, soundbit mcp serves the same tools over stdio, with its own song and a workspace of your choice:

"soundbit": {
  "command": "soundbit",
  "args": ["mcp", "--root", "/path/to/your/music/folder"]
}

Then ask for music:

Make an exciting, orchestral-sounding battle theme for my game: D minor, 160 bpm, with brass, strings, timpani and a loop I can play forever.

Write an upbeat chiptune song for my game's title screen: a catchy pulse-lead hook, D major, around 128 bpm, with a loop I can repeat.

Put this song on the NES profile and fix whatever it complains about.

The two example songs clash-of-banners and pixel-sunrise were composed exactly like that.

MCP tools

Each tool's schema describes its parameters, units and ranges; agents read them on their own.

Read tools return compact text views as well: a tracker grid per pattern and an arrangement grid with tracks as rows and bars as columns.

Chip profiles

Profiles are soft constraints: the song tells you what breaks the rules and why, and edits that would add new problems are refused with an explanation.

How it works

 Desktop editor (Tauri + Svelte)     MCP client (stdio or HTTP)      soundbit CLI
              │                               │                         │
              └────────────────┬──────────────┴─────────────────────────┘
                               ▼
                    soundbit-app: commands, undo/redo, sessions, presets
                               │
        ┌──────────────────────┼──────────────────────────┐
        ▼                      ▼                          ▼
  soundbit-core          soundbit-engine            soundbit-formats
  song model and         sequencer, voices,         .sbproj files, presets,
  chip profiles          mixer, real-time player    WAV export
                               │
                               ▼
                         soundbit-dsp
                         oscillators, FM, filter, reverb (no_std)

Every edit, from a click in the piano roll or from an agent, is a command executed against one shared session. The audio thread never allocates or locks: songs are compiled into schedules off the audio thread and handed over through lock-free queues. Project files (.sbproj) are readable, versioned JSON. The design decisions are recorded in docs/adr.

Documentation

The Wiki covers getting started, the editor, sound design and presets, chip profiles, connecting AI agents, the project file format and the architecture.

Development

Contributions are welcome: see CONTRIBUTING.md, and SECURITY.md for reporting a vulnerability privately.

cargo fmt --all --check
cargo clippy --workspace --all-targets -- -D warnings
cargo test --workspace
cargo xtask check          # crate dependency rules and file-size limits
cd apps/desktop && npm run check && npm run lint && npm test

Acknowledgements

SoundBit's simple song model is inspired by Bosca Ceoil by Terry Cavanagh. The reverb follows the structure of Jezar's public-domain Freeverb, and the filter Andrew Simper's trapezoidal state-variable filter; see THIRD_PARTY_NOTICES.md.

License

Copyright (C) 2026 Renas Demirbas

SoundBit is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. It is distributed in the hope that it will be useful, but without any warranty; see the license for details.

Music you make with SoundBit is yours: the license covers the program, not your songs.