Regression Postmortem

Find out why it broke, turn that into a test so it can't silently break again, then write it up so the team learns something. Two modes: postmortem (default) and release notes.

Postmortem mode

Step 1: Pin the symptom

Get specifics: the exact error/traceback (Sentry link or log lines), the endpoint or page, who's affected (all users, one org, one role), when it started, and what was deployed around then. If it's an active production incident, the first move is mitigation (revert the deploy, toggle the flag off). Ask whether that's done before investigating.

Step 2: Reproduce

Reproduce locally before guessing at causes. Best form is a failing test at the highest seam that shows the symptom (API test for an endpoint bug). If you can't reproduce, list what's different between local and the failing environment (data, settings, env vars, versions, Celery vs sync) and narrow down from there.

Step 3: Find the change

Fastest first: