Postmortem Attendees

Right people.

Required attendees

Incident commander. Owned the response; has the timeline.

On-call engineers from incident. Ground truth on what happened technically.

Service owners for affected services. Long-term context on the system.

Optional attendees

Adjacent teams whose systems were affected. Cross-team learning.

Product manager. Customer impact context; product implications of contributing factors.

Engineering leadership. Resource decisions may follow from contributing factors.

Pitfalls

Mandatory attendance for the entire org. Becomes a 30-person meeting; nothing gets accomplished.

Skipping the postmortem because attendance is hard. Async-only loses tone and dynamics.

Including too few people. Missing context produces shallow postmortems.

Size guidelines

5-10 people for sev 1 postmortems. Enough perspectives; small enough to function.

3-5 people for sev 2. Smaller scope; tighter group.

Cross-team incidents: representatives from each, not whole teams.