#kotlin

Before a single feature line goes in, the build system has to be right. This is what setting up Gradle convention plugins for a 16-module Android project looked like in 2026 — including every AGP 9.x breaking change that hit along the way.

I asked Claude to design a senior-level Android engineering challenge for me — the kind that covers everything a production app actually needs. It delivered a 968-line spec. This is what it came up with, why the architecture decisions matter, and what the 10 hardest technical challenges look like before a single feature line is written.