0006 — Two independent implementations, byte-identical

• Status: accepted
• Date: 2026-07-27

Context

A specification whose only evidence is one implementation cannot prove interoperability: two parties might each build against the prose and disagree on the bytes. And an implementation graded only against its own output proves nothing (a circular oracle).

Decision

Every construction carrying a security or interoperability claim is demonstrated by two independent implementations from different language runtimes (Go and Rust) producing byte-identical output, each cross-validated against an independent, non-circular oracle whose expected values come from the relevant RFC, FIPS, or NIST vector or a from-scratch constructor — never from the code under test. The CDDL module is machine-validated against the committed vectors.

Consequences

Byte-parity is the strongest interoperability evidence N-AALP offers and is enforced in CI. The deterministic ML-DSA variant (rnd = 0) is required so signatures are byte-identical across implementations. Additional-language SDKs are graded against the same corpus through a shared conformance-adapter contract, so adoption does not weaken the parity guarantee.