Ethereum Foundation adopts SHA and BLAKE for Layer 1

Ethereum Foundation will replace Poseidon with SHA and BLAKE hash functions for Layer 1, citing SNARK advances. Production leanVM is set for 2027, with broader deployments in 2028.

The Ethereum Foundation is moving away from the Poseidon hash function in its Layer 1 (L1) roadmap after eight years of research and significant investment in post-quantum cryptography. Instead, it will adopt established hash functions such as SHA2, SHA, and BLAKE2/BLAKE3. This shift is driven by recent advances in SNARK (Succinct Non-Interactive Arguments of Knowledge) design, especially binary-field SNARKs. These developments now enable traditional hash functions to perform on par with Poseidon in zero-knowledge proof systems. Standard hashes, which have undergone extensive cryptanalysis and are considered more secure and mature, can now be efficiently used in Ethereum’s future architecture. The roadmap includes a production-grade leanVM targeted for 2027, with broader deployments across consensus, data, and execution layers expected in 2028. While Poseidon has been important for zkRollup and zkVM applications, the Foundation is now prioritizing the security and efficiency of traditional hash functions for post-quantum resilience.