Progress without memory is fragile
AI-assisted development moves quickly, but speed makes it easy to overwrite working behaviour while solving the next problem. A checkpoint records what is believed to work, the evidence supporting that belief and the boundary that future changes must preserve.
Separate evidence from confidence
A repository link is not a code audit. A successful build is not proof that every feature works. An owner statement is useful evidence, but it should remain labelled as owner-reported until an independent check exists. Recovery becomes trustworthy when every claim keeps its evidence class.
Freeze, change, verify
The practical cycle is simple: inventory the current state, record known defects, freeze the accepted checkpoint, define one bounded next release, execute it, and attach fresh test evidence. This reduces regression risk and makes rollback a product habit rather than an emergency ritual.