Ethereum Foundation Abandons Poseidon for SHA and BLAKE

Ethereum researcher Justin Drake announced that the Ethereum Foundation is abandoning Poseidon, a specialized hash function used in zero-knowledge proof systems, and pivoting towards established hashes such as SHA and BLAKE for Ethereum's Layer 1 (L1) architecture.

This shift follows advances in binary-field SNARKs, including Binius and Flock, which make conventional hash computations substantially more efficient.

The change does not mean Poseidon is being removed from existing zk-rollups or applications that use it. However, the Ethereum Foundation's new roadmap targets a production-grade leanVM in 2027, followed by consensus, data, and execution-layer deployments in 2028.