Production ML-DSA Verification in 350 Lines of Python

This article presents a pure Python implementation of ML-DSA (Module-Lattice-Based Digital Signature Algorithm) verification, designed for production use. The code is 350 lines, supports all parameter sets, and is available on PyPI as 'mldsa'. It uses Python integers and SHA-3 from hashlib, with no external dependencies. The author details the implementation structure, performance benchmarks (e.g., 230 verifications/sec for ML-DSA-44), and testing methodology including Wycheproof vectors and mutation testing. The goal is to enable post-quantum authentication in client applications that cannot use C extensions.