Contributing

Run focused PHPUnit coverage and the repository's source-quality checks for changed code.

Payload-codec fixes also follow the organization regression-corpus contract. Add the smallest cross-language wire fixture under tests/Fixtures/CodecRegression/.

Fixtures are append-only and preserve protocol version, value and type, framing, and stable failure policy. Run:

python scripts/ci/validate-regression-corpus.py --base-ref <target>

The server's PHPUnit codec corpus runner derives its fixture globs from regression-corpus-policy.json. New portable codec-regression-v1 selectors therefore join the PHP execution inventory automatically. Formats without an official PHP executor are rejected by corpus validation and cannot contribute guarded growth.

A wire-codec defect also needs an append-only counterfactual proof under tests/Fixtures/CodecRegressionProofs/. The proof pairs each new codec fixture with one changed boundary path and a changed Feature PHPUnit test. The test uses ServerCodecRegressionFixtureExecutor::exercise() exactly once. That shared executor invokes a zero-argument proof callback. For each counterfactual source snapshot, validation embeds the selected fixture in the claimed boundary and routes its official PHP codec calls through a stateless proxy. The validator requires the proxy's per-run boundary attestation, while proof adapters that read verifier input, mutate verifier state, branch, or dispatch dynamically are rejected. Complete source qualification runs the proof against the candidate, the target revision, and a candidate with only that boundary reverted. The regression must pass on the candidate and fail on both defective revisions. Review the fixture and HTTP reproducer together; substituting an unrelated valid fixture cannot prove the causality of a request that deliberately submits malformed bytes.

Transport and resource fixes are different: HTTP body limits, streaming storage, reference retention and metadata-only reads need their real HTTP, integrity, memory and recovery regressions. When no new wire fixture is appropriate, the validator reports changed payload paths for maintainer review without requiring artificial corpus growth. The PR must explain unchanged wire semantics and show the original failure and the corrected behavior at the actual affected surface. Review that evidence before merging. Existing fixtures remain immutable and run in the normal suite; wire-format, type-identity, framing or codec acceptance defects still require portable fixtures and the proof above. A green inventory check alone is not qualification.