Reading the standard library

Every time I revisit a project after six months, I find at least one place where past-me wrote a comment that present-me has now stopped trusting. Comments rot faster than code.

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.

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.

Most retry logic I've removed turned out to be hiding a real bug. The retries made the failure invisible, and the bug compounded for months in the background.

Caches solve a problem and create three new ones: invalidation, observability, and the slow drift between what the cache thinks is true and what the source thinks is true.

When a system surprises me, my first instinct used to be to fix the surprise. Now my first instinct is to figure out which mental model of mine was wrong, and update that.