A modern cross-platform music player built with Flutter and Rust. The spiritual successor to Songbird and Nightingale.
A product of MPLS LLC. Visit loonbox.app.
- Local music library — scan folders, watch for changes, full metadata extraction
- Rust audio engine — Symphonia decoder + cpal output with gapless playback and sample-rate resampling
- MusicBrainz integration — single-track lookup, album lookup, and full library auto-tag with confidence scoring
- 10-band parametric EQ — 17 built-in presets, real-time DSP in the Rust pipeline
- Audio visualizers — spectrum analyzer, waveform, oscilloscope, VU meter
- Embedded browser — WebView2 with Rust filtering proxy and adblock
- Feather theming — 5 built-in feathers (Blue Monday, Purple Rain, Pink Martini, Gonzo, Nightingale) with full theme customization
- Smart queue — shuffle, repeat modes, queue management
- Playlists — create, edit, reorder; smart playlists coming soon
- Keyboard shortcuts — play/pause, next/prev, volume, mute
- System tray — minimize to tray, media controls from tray icon
- Media keys — Windows SMTC integration (media overlay + hardware keys)
- i18n-ready — all user-facing strings localized via ARB
| Layer | Technology |
|---|---|
| UI & State | Flutter, Riverpod |
| Audio Engine | Rust (Symphonia + cpal), via flutter_rust_bridge |
| Metadata | Rust (lofty), MusicBrainz REST API |
| Database | Drift (SQLite) |
| Platform | Windows, Linux, macOS (no mobile for v1) |
LoonBox carries forward the spirit of Songbird (2006-2010, POTI Inc.) and its community fork Nightingale (2012-2018). While LoonBox is a ground-up rewrite — no XULRunner, no Gecko, no C++ — the design DNA of those projects lives on:
- Feathers (theming system) — Songbird coined the term; LoonBox inherits it
- Extension architecture — inspired by mashTape's provider plugin pattern
- Library schema — evolved from Songbird's EAV metadata model into a denormalized, type-safe schema
- Smart playlists — modernized from
sbILibraryConstraintBuilderinto a rule-based DSL
The git history of this repository preserves the full lineage — Songbird's initial import through Nightingale's final commits, followed by the LoonBox rewrite.
See BUILDING.md for build instructions.
git clone https://github.com/mplsllc/LoonBox.git
cd LoonBox
flutter pub get
flutter_rust_bridge_codegen generate
flutter runSee CONTRIBUTING.md for guidelines.
By submitting a contribution, you agree to the Contributor License Agreement.
See ROADMAP.md for the full development roadmap.
Coming soon:
- Feather shells (full layout transformations, including a Winamp-style skin)
- Lua extension system with The Nest marketplace
- Fullscreen visualizer mode with user-uploadable visualizers
- Tremolo (decentralized music distribution)
- Subsonic server integration
LoonBox is licensed under the GNU Affero General Public License v3.0.
Ecosystem carve-out: Feathers (themes) and extensions (plugins) that interact with LoonBox solely through the documented public APIs may be distributed under any license. See LICENSE for details.
- loonbox.app — Official website
- mp.ls — MPLS LLC
- GitHub — Source code