timothy
fba5233caf
168 records -> docs/decisions/records/<area>/<topic>.md (163 active, 23 dirs) and docs/decisions/archive/<area>/<topic>.md (5 archived). The filename IS the key, so one-active-record-per-key becomes a filesystem property rather than a validator check, and supersession becomes a `git mv`. WHY: the monolith was a concurrency problem before an aesthetic one. A 3,900-line append target made parallel sessions collide -- PR #605 and PR #614 both hit append-vs-append conflicts during routine rebases, and hand-resolving those inside the corpus is exactly the operation the rationale-rewrite guard exists to police. HOW IT IS VERIFIED: a ~170-file diff cannot be meaningfully read, so correctness does not rest on reading it. The parser was taught BOTH formats first, so the body-diff guard parses the old form at the merge-base and the new form at head -- the migration validates itself, no bypass. The proof is a field-level equivalence harness: 168 records before and after, zero lost, zero gained, zero field mismatches, zero rationale bodies differing. Reviewers should scrutinise the harness; it is the actual evidence. What measuring caught that reading would not have: - ~500 lines sit OUTSIDE any record -- decisions.md's lifecycle schema and each topic file's preamble, mostly the only copy. Source files are kept and stripped, never deleted. They also cannot be filed per-area: topic files hold several areas and 4 of 23 areas span several files. - Archive discovery was a non-recursive glob; after the split it found ZERO archived records, surfacing as four bogus "supersedes points to unknown key" errors rather than an obvious failure. - ~32 live docs point into the corpus BY DATE, which the split dangles. Each stripped file now ends with a generated "Records formerly in this file" index, which also rescues the identical breadcrumbs in old issue comments. - decisions.md's "In this file:" list was 97 same-file anchor bullets that the split makes WRONG, not merely stale. Dropped; the generated index replaces them with links that resolve. The equivalence harness now runs against a checked-in FIXTURE, not the live corpus. The earlier version migrated the real tree, which made it a one-shot: the moment the migration landed there was nothing left to move and the tests failed for reasons unrelated to the code. A fixture keeps them testing the SCRIPT rather than the repo's current state. Keys preserved verbatim, warts included: `sched` (12) and `scheduling` (1) remain two directories for one concept. Renaming a key is not a move -- it changes identity, breaks the equivalence proof, and invalidates MemPalace's per-key drawers. Taxonomy normalisation is separate work. refs #610
4.8 KiB
key, title, status, since, supersedes, superseded-by, rule, signals, mechanics
| key | title | status | since | supersedes | superseded-by | rule | signals | mechanics |
|---|---|---|---|---|---|---|---|---|
| docs.decision-lifecycle | 2026-07-21 — Decision records carry a lifecycle schema, validated by a script; append-only-by-diff is retired (#521) | active | 2026-07-21 | docs.append-only-guard@2026-07-12 | none | every decision `##` record (active or archived) carries a 5-field metadata block (`key`, `status`, `since`, `supersedes`, `superseded-by`) checked by `scripts/decisions_validate.py`; a record is never deleted or line-edited to reverse a call — it is moved to `docs/decisions/archive/` with `status: superseded`/`retired` and a reciprocal `superseded-by`/`supersedes` key pair to its replacement. | decision lifecycle, supersession, archive · paths: `scripts/decisions_lib.py`, `scripts/decisions_validate.py`, `scripts/build_decisions_catalog.py`, `docs/decisions/archive/` · issues: #520, #521 | `scripts/decisions_validate.py` (`PYTHONPATH=. python3 scripts/decisions_validate.py`); catalog regen `scripts/build_decisions_catalog.py`; `docs/decisions/migration-map.md` |
This replaces docs.append-only-guard (ersatztv#303 H9), not just extends it. The old guard treated
docs/decisions.md as a single append-only text file: any line-delete was blocked by a Husky
commit-msg hook + CI job, and a "supersession" was a hand-written > **Superseded …** banner
prepended to the old entry plus an (superseded) Index tag — prose conventions an agent had to
remember and apply correctly by hand, with no machine check that the banner, the tag, and the new
entry's back-reference actually agreed with each other. That is exactly the failure mode this arc
(#520/#521) set out to fix: state should be derived and checked, not asserted in prose (the same
throughline as #303 H6's ## Done-when).
The new model. Every decision record — whether still in force or not — gets a key (dotted,
stable identity independent of its heading text or which file it lives in), a status
(active/superseded/retired/legacy-unmigrated for anything not yet carrying the schema), a
since date, and a reciprocal supersedes/superseded-by pair of keys. scripts/decisions_lib.py
parses the schema; scripts/decisions_validate.py enforces: at most one active record per key;
superseded/retired records MUST live under docs/decisions/archive/, never in an active file;
an active record MUST NOT live under archive/; every supersedes/superseded-by key must
resolve to a record that actually exists (active or archived); and — replacing the append-only
guard's line-delete detection — a record's rationale prose (the schema strips only the contiguous
metadata block before comparing) must not change between a PR's base and head unless the commit
carries the rationale-edit marker (Decisions-Edit: yes, a git trailer since #609 — see
ci.decisions-edit-trailer), and a record that disappears from the active set without a matching
archive copy is flagged as an unlogged removal. scripts/build_decisions_catalog.py regenerates
docs/decisions/README.md, a compact router listing only active records by key, so an agent
doesn't have to read the full chronological log (or the archive) to find the current rule.
Why this is a strictly better enforcement of the same spirit, not a loosening. The old guard's
actual invariant was never "no line may change" — it was "history is never silently rewritten to
erase why we changed our mind." A hand-prepended banner satisfied that invariant by convention; a
validator that checks reciprocal keys, archive placement, and rationale-prose stability satisfies it
by construction, and additionally catches classes of mistake the old guard could not (a supersession
banner added without moving the entry out of the active read-path; a superseded-by reference to a
key that doesn't exist; two active records quietly claiming the same key after a copy-paste).
The rationale-edit marker is kept, narrowed to its one remaining legitimate use — an actual
rationale-prose edit (fixing a factual error) — since routine lifecycle moves (a status flip, an
archive relocation) are now marker-free and machine-checked instead.
This PR is the first to exercise the new regime, on itself. docs.append-only-guard (the H9 half
of #303's combined H9/H3 entry; H3's root-screenshot guard is untouched and stays active) is marked
status: superseded and relocated to docs/decisions/archive/release-ci-governance.md, with this
record as its superseded-by and this record's supersedes pointing back — the same-PR supersession
pattern the new rule itself mandates for every future reversal. docs/decisions/migration-map.md
tracks the legacy-heading → key → status → location mapping as the rest of the log migrates
(ersatztv#520/#521, ongoing — most existing headings remain legacy-unmigrated until touched).