Sidecars and the things they hide

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

If a config file has more than a dozen options, half of them aren't being used. The other half are being used in ways the original author didn't predict.

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.