A production-ready, pure-Python ML-DSA (post-quantum digital signature) verifier has been published as a single 350-line file with no dependencies, available on PyPI as 'mldsa'. It supports all ML-DSA parameter sets (ML-DSA-44, 65, 87), works with Python 3.8+, and is dual-licensed CC0/0BSD. The implementation achieves ~230 verifications/second (60x slower than Go but acceptable for many use cases). It is thoroughly tested with Wycheproof and CCTV test vectors, mutation testing via muzoo, and achieves 96% branch coverage. The project originated as a cross-implementation check for a Go ML-DSA implementation, and is intended to unblock client applications that cannot use C extensions for portability reasons, accelerating migration to post-quantum authentication.
