---
title: "leanXMSS: which blockchains use it"
url: "https://hardyindex.com/algorithms/lean-xmss"
---

# leanXMSS

An Ethereum research variant of XMSS designed for validator signatures that can be aggregated efficiently. It is in devnet testing and is not covered by a published standard.

- **Quantum status:** Believed quantum-resistant. No post-quantum scheme carries a proof of resistance.
- **Standard:** No published standard.
- **Family:** hash based stateful.
- **Also known as:** lean signatures.

## Rated chains using it

- [Ethereum](https://hardyindex.com/chains/ethereum.md): validator consensus, testnet. Versioned interoperability devnets; pq-devnet-1 to pq-devnet-3 completed by March 2026. Source (statement or write-up): https://pq.ethereum.org/
- [Tezos](https://hardyindex.com/chains/tezos.md): validator consensus, testnet. Hash-based XMSS attestations with STARK aggregation from the LeanEthereum project, on Quantumnet and not on mainnet. Source (statement or write-up): https://spotlight.tezos.com/introducing-quantumnet/

## Sources

- [Post-quantum Ethereum](https://pq.ethereum.org/), Ethereum Foundation. Accessed 19 October 2026.