Building quantum-resilient blockchains with ML-DSA digital signature integration

Blockchain and quantum computing are both advancing rapidly, making their intersection a significant research challenge. Blockchain systems rely on public-key digital signature schemes to authenticate transactions and maintain the integrity of the chain. However, the mathematical problems underlying commonly used schemes in current blockchain platforms are vulnerable to quantum attacks. Post-quantum cryptography should be considered as a potential long-term replacement. This study investigates the integration of ML-DSA, the NIST standard derived from CRYSTALS-Dilithium, into a Substrate-based blockchain. The research comprises two components: the practical integration of the scheme and the evaluation of key metrics against classical digital signature algorithms to assess its performance impact. The Substrate Blockchain, a modular, open-source blockchain framework, is used for experimentation. The results show that ML-DSA can be integrated into the Substrate transaction flow and provide a more realistic view of the implications of adopting post-quantum digital signatures than comparisons of cryptographic primitives in isolation. Across most metrics, ML-DSA performance remains acceptable in absolute terms; however, the overhead increases with security level and affects more metrics than others. The most significant system cost arises from extrinsic size, which substantially reduces block capacity.