compat-trial

Experimental compatibility replay runner

Implements CRR-V0-001..007 using internal/procgroup. This is owned synthetic fixture replay, not external execution, candidate scoring, or host qualification. Every case keeps accepted_by: NOT_PRODUCED.

The descriptor JSON has exactly the CTR-V0-001 keys. Concrete experimental encodings are: environment as an array of NAME=VALUE strings, build flags as a string array, CGO_ENABLED as "0" or "1", timeouts as "10s" and "120s", gold provenance as a string, and build_bounds as an object. Reference paths are relative to the manifest directory. argv excludes argv[0] and must begin with --owned-fixture and one of the closed operations in fixture.go. Missing, unknown, duplicate and null fields are rejected. source is nonempty prose. The only implemented host_profile is owned-synthetic-process-group.

Snapshots are canonical sorted USTAR archives of regular files/directories, with zero timestamps/ownership metadata and preserved permission modes. Symlink archive entries and nonregular reference files are refused. Each repetition gets a fresh scratch tree and a private executable copy of the verified bytes, preserving its execute permission. Reference hashes and native Go build identity are checked before any replay launch; later edits to source artifact paths cannot replace the captured bytes.

go build -trimpath -o /tmp/compat-trial ./tools/compat-trial builds a runner whose registry permits only its own native fixture entrypoint and four fixed stdin fixtures. /tmp/compat-trial -fixture-dir /tmp/new-owned-fixture creates an example bundle; -manifest /tmp/new-owned-fixture/manifest.json replays it. The fixture directory must not already exist.

For owned versioned fixtures, run the repository's fixed build helper from the repository root:

GOTOOLCHAIN=local go run ./tools/compat-trial/build-fixtures -out /tmp/new-owned-build

The helper compiles the two repository-owned fixtures/old and fixtures/new packages under Go 1.27.0, CGO disabled, -trimpath, no build VCS data, and disabled module-network access. It embeds their artifact SHA256s into the resulting runner. fixture-manifest.json records the source and artifact hashes and build identity. Use those old and new artifact paths/hashes in a synthetic descriptor to observe different. The registry is never loaded from a descriptor, its adjacent files, or an arbitrary executable-registration option. The generated registry files are receipts, not authorization inputs. Tests build the same fixed owned variants and exercise validation and actual old/new replay.

Output records describe observed exits only. Case launch counts remain separate from record counts. Overflow records preserve bounded captured prefixes, name the stream, and withhold comparison; their digests are not complete-output claims. An overflow aborts only the rest of its case. Each task entry's 120-second budget actively cancels its current repetition; every repetition has a 10-second ceiling and a one-second shutdown bound. SIGINT/SIGTERM enter that same cancellation path.

Containment covers the owned process group. Session escape, forced termination of the supervisor itself, external execution and an E:99 sandbox remain unqualified. The filesystem observer sees only net scratch-tree transitions: transient changes and outward effects are unobservable. Effect observations list declared and undeclared observed effects and declared-but-absent effects; declared effects do not fail a case. The caller must not read PASS as a broader sandbox or behavioral-correctness claim.

Focused validation:

GOCACHE=/tmp/corvint-go-build-cache GOTOOLCHAIN=local go test -race -count=1 ./internal/procgroup ./tools/compat-trial/...
GOCACHE=/tmp/corvint-go-build-cache GOTOOLCHAIN=local go vet ./internal/procgroup ./tools/compat-trial/...

The coordinator owns the full frozen parity replay. An earlier unfiltered package run exceeded its 10-minute test-wide timeout; filtered parity checks passing does not clear that result. No external trial, label acceptance, cost score or release qualification is produced by these tests.