Echobox is proprietary software, but it includes open-source components from third parties. The list below names the major direct dependencies; the in-app About → Third-party software screen renders the full transitive set with their individual licence texts (generated from Cargo.lock and Flutter's built-in LicenseRegistry from pubspec.lock).

We acknowledge these projects and reproduce their licences in compliance with the attribution terms each licence requires.

Audio engine (Zig)

The Zig standard library (MIT)

Core (Rust)

symphonia — multi-format audio decoder (MPL-2.0)
rubato — sample-rate conversion (MIT)
rustfft — FFT (MIT/Apache-2.0)
tokio — async runtime (MIT)
reqwest — HTTP client (MIT/Apache-2.0)
rusqlite — SQLite bindings (MIT)
quick-xml — UPnP/SSDP parsing (MIT)
sentry — optional crash reporting (Apache-2.0)
wavpack — WavPack decoder (BSD-3-Clause)

UI (Flutter / Dart)

Flutter framework (BSD-3-Clause)
flutter_rust_bridge — FFI codegen (MIT)
sentry_flutter — optional crash reporting (BSD-3-Clause)
three_js — 3D scene rendering for the Room Designer (MIT)
permission_handler (MIT)
app_links (BSD-3-Clause)

Android

androidx.media3 — MediaSession + Cast bridge (Apache-2.0)
Google Cast Framework (Google APIs Terms of Service)

Online services

Connections initiated only when you use the corresponding feature:

Last.fm API (scrobbling)
ListenBrainz (scrobbling)
LRCLIB (lyrics)
Radio-Browser (internet radio directory)
MusicBrainz Cover Art Archive (artwork backfill)
iTunes Search API (artwork backfill)
Sentry (optional, opt-in crash reporting)

The complete transitive dependency set with full licence texts is shipped inside the app at About → Third-party software. We refresh this page when the major-dependency list changes; the in-app surface is always exhaustive.