Ethereum Ditches Custom Hash Function for Time-Tested Alternatives

Ethereum has decided to abandon its custom Poseidon hash function after eight years of use. This decision comes as traditional cryptographic standards like SHA and BLAKE2s have become more efficient for zero-knowledge systems, making custom solutions unnecessary.

Bitcoin pioneer Adam Back supports this shift, favoring well-studied and reliable algorithms over experimental ones. Advances in binary-field mathematics have made it possible to achieve the same level of security with conventional hashes, eliminating the need for Ethereum's custom solution.

The transition will be completed by 2028, with the LeanVM virtual machine launch in 2027 marking the first step towards this post-quantum cryptography upgrade. This move aligns with Ethereum's goal of improving its cryptographic standards and ensuring the security of its network well into the future.