Claude Code shipped roughly 25 releases last month. My setup, 400 lines of CLAUDE.md, four skills and a guard hook, had exactly zero tests against any of them.
That bothered me, because this configuration has behavior, and behavior breaks. A new model version ships and suddenly a skill stops triggering. Nothing errors. Nothing goes red. The agent just quietly stops doing the thing you taught it, and you notice three weeks later when the code review comes back weird.
So I built CI for it: config-drift-checker turns your CLAUDE.md, skills and hooks into eval cases and re-runs them on every Claude Code release and every PR that touches the setup.
But a tester you've never seen fail is worthless. So I sabotaged my own setup to test the tester.
Attempt one: the sabotage that did nothing
