Ethereum Foundation researcher Justin Drake announced on August 13 that the network's layer 1 will abandon Poseidon after an eight-year, eight-figure research effort and pursue established hash functions such as SHA-2 or BLAKE2s. As Drake stated in his X post, "Goodbye, Poseidon!" describing the decision as the result of an "8-year, 8-figure rabbit hole" in post-quantum cryptography. Poseidon emerged in 2019 as a hash function designed for zero-knowledge proof systems, but advances in proof-system design have now changed the trade-off that initially favored Poseidon. According to Drake, binary-field SNARKs can prove about 1 million traditional hash calls per second on a laptop, with an overhead of roughly 100 times compared with native CPU execution. The decision concerns Ethereum's future L1 architecture rather than an immediate removal from existing applications, with rollups, virtual machines, and other projects that already use the function not required to replace it.
Binary fields allow proof systems to process Boolean logic more naturally than earlier SNARK designs that relied on large prime fields, where bit-based operations such as XOR could be costly to represent. Working over the smallest prime number, two, allows binary-field systems to align their calculations with zeros and ones used in conventional computing. Research projects including Binius and Flock contributed to the performance gains, with Binius applying binary-field arithmetic to zero-knowledge proofs and Flock focusing on proving large batches of Boolean calculations, including computations involving SHA-256, Keccak, and BLAKE3. SNARK.fast, an open automated research project using artificial intelligence, reached 1.8 million BLAKE3 compressions per second, representing a 255% improvement over its starting benchmark. The decision changes the relationship between Ethereum's hash functions and its proof infrastructure, allowing researchers to build SNARKs around hash functions that already have long security records.
Drake linked the decision to Ethereum's post-quantum security program, which is preparing the protocol for computers capable of breaking elliptic-curve cryptography. Ethereum currently relies on such systems for user accounts and parts of its consensus and data infrastructure. According to Drake's assessment, recent advances in AI-assisted cryptanalysis have created setbacks for more complex post-quantum systems, specifically citing HAWK, a lattice-based signature design, and SQIsign, which relies on isogeny-based cryptography. Hash-based signatures use relatively simple and extensively studied assumptions, although individual signatures can be too large for direct use at Ethereum's present scale. SNARK aggregation offers a solution, allowing proof systems to verify many hash-based signatures and compress the result into one smaller proof for the network, rather than requiring every signature to be placed and checked separately. Drake credited the Binius research by Benjamin Diamond and Jim Posen in 2023, which adapted proof techniques to capture standard hashes efficiently, alongside newer work called Flock.
The Ethereum Foundation's post-quantum team is working on binary-field infrastructure as part of leanVM, a minimal zero-knowledge virtual machine intended to verify and aggregate cryptographic proofs. Drake said the current schedule calls for a production-grade leanVM in 2027, with deployments involving Ethereum's consensus, data, and execution layers planned for 2028. The schedule sits within Ethereum's Strawmap, a technical coordination document extending through 2029 rather than a finalized activation calendar. The planned 2028 work would apply the resulting proof technology separately across the consensus layer, data layer, and execution layer. Wallet-level preparations are already being tested, with an Ethereum researcher demonstrating account protection using a SPHINCS-based signature verifier in June, requiring about 127,000 gas and carrying a 3,704-byte signature with an estimated verification cost of roughly $0.07 per account. The move removes the need to wait years for Poseidon to survive cryptanalysis, speeding deployment.
Ethereum ($ETH) showed no clear positive reaction to the roadmap update, trading near $1,875 at the time of writing, down about 2.6% over the previous 24 hours as the broader crypto market weakened. The latest comparison shows how Ethereum's development priorities have widened since 2023, with scaling remaining central but privacy, quantum resistance, and verifiable protocol design now carrying more weight. Each major proposal must still move through Ethereum's research and governance process, with native rollups, alternative instruction sets, and post-quantum signatures remaining technical directions rather than confirmed features with fixed activation dates. The updated roadmap places more weight on simplifying the protocol specification so developers can formally verify its behavior, though the post announced no immediate software release, hard fork, or mandatory action for users.
