Read the config as it was when the pager fired

The incident started at 02:47. The postmortem starts at 11:00, and the first question is always the same: what was different?

You don't reconstruct. You query. config.yml?at=2026-06-09T02:47:00Z returns the file exactly as it was when the pager fired. /api/v1/journal?path=deploy/&op=write lists every write under deploy/ in the incident window, each with a timestamp and a stored copy of the result. A ?diff between the revision before and after shows the three lines that did it.

No grepping shell histories. No "I think I changed that around two."

The postmortem stops arguing about what changed and reads it.