Open Source Licenses

Last updated 17 September 2026

ScoreLens is built on work other people gave away. This page lists the components it ships with and the licences they are used under. Each licence text is available from the project's own repository.

Recognition server

Sheet music recognition uses homr, licensed under the GNU Affero General Public License v3.0. The AGPL requires that users of a network service built on the software can obtain its source, so the ScoreLens recognition server is published in full. It also uses FastAPI (MIT), RQ (BSD-3-Clause) and Redis (BSD-3-Clause / RSALv2).

Score rendering and playback

• OpenSheetMusicDisplay — BSD-3-Clause
• smplr — MIT
• midi-writer-js — MIT
• fast-xml-parser — MIT

Instrument sounds are General MIDI soundfonts derived from the FluidR3 GM soundfont, distributed under the MIT licence by the midi-js-soundfonts project.

Application framework

• React and React Native — MIT
• Expo and its modules (application, asset, audio, camera, constants, crypto, file-system, font, haptics, image-manipulator, image-picker, linking, print, router, sensors, sharing, splash-screen, sqlite, status-bar) — MIT
• react-native-reanimated, react-native-worklets, react-native-gesture-handler, react-native-safe-area-context, react-native-screens, react-native-svg, react-native-webview — MIT
• @shopify/react-native-skia — MIT
• @noble/hashes — MIT

Typefaces

Unbounded and Golos Text are used under the SIL Open Font License 1.1, packaged by the expo-google-fonts project (MIT).

Sample score

The sample piece included with the app is in the public domain. Its engraving was produced from a CC0-licensed MusicXML source.

If you believe something is listed incorrectly or is missing, write to hello@scorelens.app and it will be fixed.