Ethereum L1 Plans Shift From Poseidon to SHA or BLAKE as SNARK Tech Advances

The Ethereum Foundation is moving its L1 cryptography plans away from Poseidon toward traditional hash functions such as SHA or BLAKE, while its current strawmap targets related deployments across the consensus, data and execution layers in 2028, according to Ethereum Foundation researcher Justin Drake.

The transition is expected to follow the development of a production-grade leanVM targeted for 2027. Drake said deployments would then extend across Ethereum’s consensus, data and execution layers in 2028. 

A key technical driver is progress in binary-field SNARKs. Those advances now allow traditional hash functions to be proven efficiently using SNARKs, reducing Ethereum’s reliance on specialized hashes designed for zero-knowledge proofs.

Poseidon was designed to be efficient in SNARK-based zero-knowledge proofs. Under the planned architecture, Ethereum would instead be able to use established hash functions while retaining efficient proving. 

The shift also fits Ethereum’s broader push toward post-quantum security, an area Vitalik Buterin has increasingly emphasized in the protocol roadmap.

Source: Justin Drake