Debugging

A terminal UI that lets you inspect live HTTP traffic on a process without reaching for Wireshark.

A small, practical use of Nix that doesn't require buying into the ecosystem.

The race detector slows things down enough to hide some timing-dependent failures.

The bug went away when I added logging. I know. Here is what was going on.

A service worked on one image and not another. The difference was invisible until we traced syscalls.

A core dump from production is a gift. Here is how I unwrap it.

We stopped rerunning flakes and started investigating them. Our suite is healthier and faster for it.

A stale cache partition was producing 'passing' builds for a bug that was 100% broken at runtime.

noeviction is the default, and the default is dangerous when you thought you were running a cache.

I used to be scared of perf record in prod. Then I wasn't.

One innocuous request_id label, 18M active series, and a very bad Friday.

A multi-day outage-adjacent incident caused by prepared statements not making it across pool boundaries.

A query that should have been a boring index scan turned into a full-table shuffle because the planner guessed wrong.

A service that could no longer bind to low ports after an innocent systemd change, and what I learned about capability sets

Pointing httptap at a flaky payments-api and watching a backoff loop reveal itself in real time.