The Ethereum Foundation is shifting away from the Poseidon hash function in its planned post-quantum architecture. Researcher Justin Drake announced the pivot on August 13, 2026, citing changes in technical performance that favor established alternatives.
Recent advances in SNARKs, which are compact proofs used to verify data efficiently, have removed Poseidon’s previous speed advantage. This development allows conventional hash functions like SHA or BLAKE to perform well enough for these systems, offering a more secure and scrutinized path forward for Ethereum’s future upgrades.
Key facts
- Justin Drake stated that advances in SNARK technology have neutralized the performance benefits once held by the Poseidon hash function.
- The Ethereum Foundation had previously considered Poseidon for leanVM, a system designed to help verify large volumes of blockchain activity efficiently.
- Sreeram Kannan, CEO of Eigen Labs, noted that established hash-based systems face fewer known attack avenues due to extensive prior scrutiny.
- Joint work by Eigen Labs, the Ethereum Foundation, and Succinct has increased proving speeds by 2.5 times.
- Preliminary targets aim for a production-ready leanVM by 2027, with broader deployments across Ethereum’s layers expected by 2028.
Why it matters
This shift prioritizes security and deployment speed by leveraging well-tested cryptographic tools rather than newer, less proven options. For users and developers, relying on established hashes like SHA or BLAKE may reduce risks associated with potential vulnerabilities in novel algorithms. It also signals that improvements in proof systems are making standard cryptographic methods viable for high-performance blockchain scaling solutions.