Correctness:
- ledger: single-flight fcntl lock over read-modify-append + fsync. Two
concurrent writers previously could fork the hash chain (read same tail,
same prev_hash). New test races 8 threads x6 appends; chain stays intact
with contiguous indices.
- small-order list: the order-8 encodings were hand-typed and unverifiable
and diverged from the canonical libsodium blocklist. A BOGUS entry is the
only dangerous direction (it down-grades a real tamper to a note, skipping
the latch), so the list is now the certain-low-order set only (y in
{0,1,-1}, reduced/non-reduced, both sign bits); order-8 edges escalate to
tamper until a derived list lands. Fail-safe asymmetry documented + tested.
- freshness: removed a tautological .
Non-functional:
- quorum members now run concurrently (ThreadPoolExecutor): a verify costs
one member's latency, not the sum (~17ms for 4 members, live).
- Wallet.quorum() memoized per state_dir: binary swap-detection hashes run
once at assembly, not on every verify; documented rationale.
85 tests green; live 4-fork wallet re-verified end-to-end.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
- dogfood/quorum/verify-{dalek,anza,risc0,betrusted}: verify-only crates
built from the pinned proven source workspaces (serial backends pinned
per fork; anza entry is the certificate-covered verify_sha512, not the
default Zebra-lineage verify())
- src/pacta/quorum.py: unanimity-required acceptance, divergence
taxonomy (semantic-edge vs unexplained/tamper), small-order/canonicity
edge flags, per-member provenance sidecars with binary hashes
- live smoke: 4/4 members agree on accept and reject
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>