Back to the Source

An agent opened a pull request in our codebase. It compiled, the tests passed, it did what the task asked, and it replaced one hook with a raw fetch. That hook was handling deduping, auth, and cache invalidation on publish. None of that was written down. An engineer caught it because he'd seen it go wrong before.
This talk is about what we did next, which was getting that knowledge out of people's heads and into files the agents read. I'll show what a rule looks like, how each one names the command that proves it and the date we delete it, and what a set of them costs to keep honest.
We were building Source at the same time, where the code is the real artifact our users own instead of an export of one, and that's a transformation happening across industries.
You'll leave with the format we use and a way to find your first rule: ask two engineers the same question and see whether they answer it the same way.