Colophon
How Kapell is made, and who to thank for it.
Typefaces
Three faces do all the work — two from Klim, one open.
- Founders GroteskTitling, headings, and interface labels.Klim Type Foundry
- Financier TextRunning text — descriptions, essays, the reading voice.Klim Type Foundry
- JetBrains MonoTelemetry, version stamps, and diagnostic readouts.SIL Open Font License 1.1, free and 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 nativeSwift using XcodeVisual 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.
- CREDITSMusicBrainzThe spine — personnel, credits, and sample lineage, maintained by volunteers.
- FACTSWikidataStructured facts and the links between them.
- PROSEWikipediaBackground prose. Text is CC BY-SA 4.0 — attribution required.
- ACOUSTICAcousticBrainzAcoustic descriptors from the open archive.
- LISTENSListenBrainzOpen listening history and recommendations.
- AUDIOReccoBeatsAudio 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.