Memory as files, from day one: append-only reasoning threads — one per concern, entries dated, never rewritten. Commits record what changed; the threads record why. The rule that made everything after it possible: the why survives.
Backfilled 2026-08-14 from the working record. Receipt: commit 5d513a4 (2026-04-27) — the hash is public, the history is private; the binding verifies when it opens.