Researchers working with the Ethereum Foundation have mapped about seven hard forks toward Lean Ethereum, a proposed overhaul targeting Ethereum’s consensus, execution and data layers, with completion targeted for the end of 2029.
The sequence uses placeholder labels from H* through L*. L* would be the final fork and complete the transition. Glamsterdam is next. Hegotá is expected to be the last fork before the full shift, with that upgrade planned for late 2026 or early 2027.
Lean Ethereum would be the protocol’s third major version, following its original launch and the 2022 Merge, which changed how the network reaches consensus. The roadmap aims to preserve backward compatibility, so existing applications should not need to be rebuilt from scratch.
Proposed changes include hash-based signatures designed to withstand quantum attacks and recursive STARK proofs. STARK proofs can show that a batch of computation was completed correctly without requiring everyone to repeat the work. Recursive STARKs can verify other proofs, allowing large amounts of activity to be represented in a compact proof that is quick to check.
The plan also proposes a two-tier state model. Its scalable tier is projected to reduce fees by more than 10x. That projection applies only to the scalable tier and does not cover every Ethereum transaction.
Ethereum researcher Justin Drake first proposed Lean Ethereum in mid-2025, and a strawmap released in February 2026 set out the strategic roadmap. The fork sequence adds detail to Ethereum’s earlier staged quantum transition plan.
Simon Yoon
Simon Yoon reports on blockchain technology for TokenPost. Send corrections or tips to [email protected].
