Three log lines that saved an outage

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.

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.

I split a 4000-line file into 12 smaller ones this week. The smaller files weren't actually easier to understand. The 4000-line file was a problem of structure, not of length.

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.