On reading other people's code

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.

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

I trust monorepos more in the second year than I did in the first. Most of the early friction goes away once the tooling catches up.

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.

I used to add a layer of abstraction the first time I saw a pattern repeat. Now I wait for the third. The waiting is uncomfortable, but the abstractions that survive that wait tend to last.

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.