Playback, synthesis, mini notation, scales, and pattern evaluation use Strudel, by the Strudel contributors. Strudel packages are licensed under AGPL-3.0-or-later; their source is available at codeberg.org/uzu/strudel.
Default sample libraries load from Strudel’s sample CDN, including piano, VCSL, uzu sounds, mridangam, Dirt extras, and the tidal-drum-machines collection collection. Audio files are streamed on demand, not bundled. See the collection for provenance and terms. Instrument names belong to their respective owners; this app is not affiliated with Roland or other instrument manufacturers.
Custom sample libraries are selected in the Strudel document and retain their own licensing terms. They require network access.