Why my CI got 4 minutes faster

Latency budgets work better than latency targets. Targets are aspirational. Budgets force you to delete features when you go over.

The team I learned the most from didn't have great tools. They had a great habit of reading each other's pull requests in full, including the parts that weren't theirs.

There's a kind of premature optimization that comes from imagining a future team. "What if someone needs to swap this out?" Often, no one does.

I keep a small log of decisions in a text file. Not architectural — just small ones. "Picked X over Y because Z." Future me reads it more than I thought he would.