One deterministic v2 log (nine facts covering every fold-relevant behavior:
genesis, after-images with minted ints, a deferred embed pending→landed,
a sameAsGeneration vector ref, a verb, a tombstone, and an all-deduped
empty commit) whose ENCODED BYTES and FOLDED STATE are both pinned by
sha256 literals. The fixture (tests/fixtures/golden-log-v2.bin, 4128 B,
byte-verified against the encoder on every run) is the shared artifact a
second reader implementation consumes — it must reproduce the identical
fold digest; the pair is normative on disagreement. The fold law is
stated in prose beside the code: generation-ordered latest-per-id,
tombstone masking, embed.landed vector application, single-hop ref
resolution, key-sorted digest.
Also: decodeGroupV2 discriminated pad filler by RECORD COUNT, silently
swallowing legitimate empty commits (an all-deduped batch at a real
generation). Pads carry generation 0 — which writers can never mint — so
the generation is the honest discriminator; empty commits stay visible.
Pins: 4/4 (encode-exact, fixture-identical, fold-exact, human-readable
spot checks beside the hashes).