Vitalik Buterin Outlines Lean Ethereum as Network’s Major Multi-Year Rebuild

Lean Ethereum as the Third Major Iteration

Ethereum co-founder Vitalik Buterin shared an updated vision for the Lean Ethereum initiative following research discussions. He positioned it as a series of gradual improvements rather than a single large fork, set to unfold over the next three to four years. Buterin called this the third major chapter in Ethereum’s development, after the original launch and the 2022 Merge that shifted the network to proof-of-stake.

The plan involves replacing nearly every major part of the protocol while aiming to keep disruption to existing applications low. Buterin noted that Ethereum has managed large transitions before and can do so again through careful implementation.

Changes to State Management and Verification

One central area of focus is Ethereum’s state—the record of account balances, smart contracts, and other data. The approach seeks to limit growth in the current dynamic state while adding new, more scalable state types. This could allow the network to support significantly larger data volumes by 2030, such as around 2 terabytes of existing-style state alongside over 100 terabytes in newer formats.

Tokens, NFTs, and many decentralized finance uses could shift to the more efficient models, potentially reducing costs substantially in some cases. Complex applications would retain access to the original state design. Buterin identified state adjustments as among the more impactful parts of the plan.

Verification methods would also change. The network plans to move toward recursive STARKs, allowing nodes to check compact proofs instead of re-executing every transaction. This aims to make the system lighter and faster overall.

Quantum Resistance and Privacy as Priorities

Quantum safety has gained significant attention in the updated roadmap. The effort targets replacement of quantum-vulnerable cryptographic elements with safer alternatives, including designs for data storage used by layer-2 rollups. Work on these areas, such as quantum-safe blobs, is already underway.

Privacy receives similar treatment, moving from an optional layer to a core design goal. New protocol components would support private, intermediary-free transactions by default. This includes evaluations for elements like mempools and state structures.

Execution Layer and Near-Term Upgrades

Longer-term considerations include exploring alternatives to the current Ethereum Virtual Machine, with options such as RISC-V under discussion. The goal would keep compatibility for existing applications while enabling a more efficient base layer.

Near-term steps feature capacity increases through upgrades like Glamsterdam, expected to bring higher gas limits and other improvements. Hegotá would follow as a bridge before deeper Lean Ethereum changes take hold. The roadmap anticipates ongoing gains in transaction throughput, data availability, and finality over several years.

Broader Context and Implementation

The initiative builds on earlier Lean Ethereum concepts introduced in 2025 and aligns with a draft long-term roadmap. Changes would roll out incrementally through future network upgrades to maintain stability.

Buterin emphasized that the work supports Ethereum’s goals around censorship resistance, open source development, privacy, and security. Developers and the community continue coordination on specifics as research progresses.