Show HN: Mosaic – A Kotlin framework for cleaner back end code

Show HN (score: 6)
Found: September 24, 2025
ID: 1558

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DevOps
Show HN: Mosaic – A Kotlin framework for cleaner back end code Backend APIs often grow into large orchestration classes full of duplicated calls and manual concurrency.

I’ve been working on Mosaic, a Kotlin framework that composes responses out of small, request-scoped “tiles.” Each tile runs once per request, dependencies resolve automatically, and independent tiles execute in parallel without boilerplate.

It’s still early (v0.2.0), but working today for caching, concurrency, and testability. Curious to hear feedback on the approach.

GitHub: https://github.com/Nick-Abbott/Mosaic Maven Central: org.buildmosaic:mosaic-core:0.2.0

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