Buterin: Lean Ethereum overhaul will take 3–4 years

Vitalik Buterin published his notes after a late-June meeting of Ethereum researchers and an updated draft roadmap known as the strawmap. He described a program called Lean Ethereum as a near-total rebuild of how the network operates, delivered as a series of upgrades over three to four years rather than a single hard fork.

The strawmap, first drafted earlier this year, lays out seven planned upgrades through 2029 and frames Lean Ethereum as the next major iteration, comparable in scope to the Merge. Buterin indicated that Hegota, currently scheduled for 2026, is likely the last upgrade that will be considered thematically “pre-Lean.” Most later forks will be part of the rebuild.

A key technical change targets how the chain stores state. Today Ethereum keeps token balances, smart contract data and other state in a single, costly format. The plan would keep that format for complex contracts while adding a cheaper second storage tier for simpler applications. Buterin described a possible 2030 scenario in which the new tier holds far more data than the current one and said many tokens, NFTs and decentralized finance apps would move to the cheaper layer voluntarily because redesigning tokens for the new tier could cut transaction fees by more than tenfold for some designs.

Work on quantum-resistant cryptography and built-in privacy has been moved up the priority list. Buterin highlighted the need to replace cryptographic components that would be vulnerable to future quantum computers and described finding a quantum-safe design for blobs — the temporary data structures used by Layer 2 systems to keep fees low — as an urgent research item. On privacy, he wrote that privacy is now treated as a first-class goal and that new features are being designed from the start with privacy in mind. The strawmap lists a quantum-proof network and private ETH transfers at the base layer among its long-term goals.

Buterin revisited plans to move beyond the Ethereum Virtual Machine as the network's main execution environment. He identified RISC-V and leanISA as likely candidates for a new execution engine while proposing that the EVM remain as a translation layer so existing applications continue to run unchanged. A different execution engine could make it cheaper to produce cryptographic proofs of transaction validity and could make it easier to build privacy directly into applications. Any transition to a new engine would be gradual: use internally first, then allow developers to build in the new format before deprecating the EVM.

Network capacity is expected to increase over the coming years. Buterin pointed to a planned large gas limit increase in the Glamsterdam upgrade, which had been anticipated in early 2026 but has not yet activated. He reiterated that Lean Ethereum will roll out as a set of incremental improvements over several years and wrote, “We've done this before (the Merge), we can do it again.”

The post followed a restructuring at the Ethereum Foundation that reduced staff by about 54 people, roughly 20% of its workforce. Buterin closed his summary with the phrase “Ethereum is CROPS,” an acronym he has used to reference the foundation's narrowed focus on censorship resistance, open source, privacy and security. The updated strawmap and its research roadmap are intended to guide protocol teams and outside developers through the planned sequence of upgrades toward the Lean design.