a73x

d0c032f1

retro: what the concurrency observers cost

a73x   2026-08-23 11:13

Commit message
retro: what the concurrency observers cost

RETRO.md
Old New
@@ -45,3 +45,10 @@ One line per push to `main`: what slowed the work down. Enforced by
45 regression where the real fact is "the UI was not compiled". It is written 45 regression where the real fact is "the UI was not compiled". It is written
46 down twice above and was still rediscovered from scratch; a RETRO entry is 46 down twice above and was still rediscovered from scratch; a RETRO entry is
47 not a gate. Filed. 47 not a gate. Filed.
48 - Concurrency observers: the same stale-fork tax, one lane later. The worktree
49 forked from a main five commits behind, so the first make ci failed on a
50 coverage floor in a package this branch never touched, and the rebase landed
51 on a wire rename mid-branch. Then a plain `git checkout <file>` to undo a
52 mutation silently ate the uncommitted comment deletions sitting in the same
53 file — mutation-test rounds and unstaged edits do not share a working tree.
54 Stage before mutating, and restore with an explicit --source=HEAD.