v3.1.6 — the Anvil Takes Many Slices

v3.1.6 — the Anvil Takes Many Slices

A real project — nine new slices in one milestone — pushed Kiln past a single
slice for the first time and found two seams. Both are closed here, and the fix
is smaller than the bug.

The deadlock

A milestone writes every slice's criteria into one locked check.sh up front, so
while the first new slice is being built the later, unbuilt slices are red. Of
the four places the kernel runs that check, the pre-seal and pre-recheck
boundaries treated that red as fatal — contradicting the kernel's own rule that
a red owned by an unbuilt slice is expected pre-build state, which the preflight
and stage-end checks already honored. It could never seal the first new
slice and never reached the rest. Now one order-aware predicate at the pre-seal
and pre-recheck boundaries tolerates a red only when every owner is a unique,
strictly-later, still-planned slice; the current slice's own red, an earlier
one, an unowned, out-of-plan, duplicate, or mixed set still fails closed, and a
regression in an already-sealed slice still reopens it — checked first on both
paths.

The refused verdict

A consequence of the previous release. With the mechanical legs on Sonnet, the
kernel hand-wrote the reviewer's verdict — "accept" — through a model courier,
which investigated and refused to author an approval it had not itself produced.
Both Sonnet and Opus refused; the fault was architectural, not a tier choice.
So the lost discipline returns: the producer authors its own
verdict. The reviewer now writes its verdict to a candidate file and returns
only an acknowledgement; the kernel invalidates any stale candidate first, reads
the written bytes back raw, validates exactly those bytes with the unchanged
mirror, and promotes them with a content-free move. The hand-write is deleted —
the change is a net deletion. The seal record, the same kind of attestation a
Sonnet hand declines to forge, now rides an opaque verb on the existing trusted
tool.

No new machinery: no ledger, lock, receipt, projection, or new tool. The seal
refusal was measured before a line was written for it.

The record

Designed by a cross-family peer pass — two families drafted the same brief
independently, then converged. Authored Claude, reviewed Sol (GPT-5.6, high)
across two rounds: the first caught three real defects the green tests missed —
a builder-level deadlock, a masked regression, an unquoted path — each fixed
with a test that would have caught it; the second approved with zero strikes.
Floors: plugin suite 110/110, harness 31/31, release gate green end to end.