postmortemlisted

# Blameless Postmortem The purpose is to make this class of failure impossible, not to explain it. A postmortem that produces no system change was a writing exercise. ## Template ```markdown # Postmortem: <title> - Date: <UTC> | Duration: <detection → resolution> | Severity: <level> - Impact: <users affected, requests failed, data lost, money — quantified> ## Timeline | Time (UTC) | Event | Source | <From the first contributing change or signal to full resolution. Every row cites a log, alert, deploy record, or message. No memory-reconstructed rows.> ## What happened <The mechanism. What actually broke, technically, in sequence.> ## Contributing factors <Multiple. Never a single "root cause". Never a person.> ## What went well ## What was hard ## Detection gap <How long until we knew, and why not sooner. This is its own finding.> ## Action items | Action | Type (prevent/detect/mitigate) | Owner | Due | Tracking | ``` ## Worked example **Blameful, single-cause — produces one useless action item:** ```markdown ## Root cause Engineer deployed a migration without checking the lock behaviour, which locked the orders table for 12 minutes. ## Action items | Action | Owner | | Remind the team to check migrations before deploying | Team lead | ``` This blames a person, finds one cause, and produces an action that changes nothing. The same outage happens again in four months with a different name attached. **Blameless, multi-factor — produces changes to the system:** ``