Kapell

Colophon

How Kapell is made, and who to thank for it.

Typefaces

Three faces do all the work — two from Klim, one open.

Site

Built with Astro and rendered to static HTML. The look comes from a hand-written set of CSS design tokens. Interface icons are Lucide, open source under the ISC licence. Analytics are by Plausible: privacy-friendly, no cookies, nothing personal collected.

Client

The Kapell app itself is native Swift using Xcode Visual Studio Code, and Claude Code Icons are from Apple's SF Symbols and Lucide.

Infrastructure

The enrichment behind Kapell runs as Go services, with PostgreSQL, DuckDB, and ClickHouse holding the data, on hardware from Hetzner managed via Ansible.

Data & open-source credits

Kapell's credits, samples, and history come from the open-data community. Many volunteers who write down what streaming flattens away. Every fact points back to the project that keeps it. If you can, contribute to them or support them.

  • CREDITS MusicBrainz The spine — personnel, credits, and sample lineage, maintained by volunteers.
  • FACTS Wikidata Structured facts and the links between them.
  • PROSE Wikipedia Background prose. Text is CC BY-SA 4.0 — attribution required.
  • ACOUSTIC AcousticBrainz Acoustic descriptors from the open archive.
  • LISTENS ListenBrainz Open listening history and recommendations.
  • AUDIO ReccoBeats Audio features and similarity.

Trademarks

Kapell plays through the Apple Music® app and the library you already have — it's a client, not a replacement, and the music and your subscription stay with Apple.

Apple Music and Apple are trademarks of Apple Inc., registered in the U.S. and other countries and regions. Kapell is an independent, third-party app and is not affiliated with, endorsed, or sponsored by Apple Inc.