Ethereum co-founder Vitalik Buterin has presented a comprehensive multi-year development plan called “Lean Ethereum,” described as the network’s third major evolution after the Merge. Following recent meetings with Ethereum researchers in Berlin and client teams in Svalbard, Buterin outlined a gradual overhaul of core protocol components over the next three to four years.
The roadmap centers on replacing the current transaction re-execution verification with recursive STARKs as a native protocol feature, enhancing security and scalability. Quantum safety is now a top priority: all remaining quantum-vulnerable cryptography will be substituted with quantum-safe alternatives, with an urgent focus on making the blob design secure. Consensus changes aim for a simpler, faster mechanism that separates the usable chain from finality, delivering finality in just one or two rounds.
A key innovation is the proposed expansion of Ethereum’s state model. Buterin envisions a 2030 architecture featuring around 2 TB of traditional dynamic state and up to 100 TB of new, more scalable—but more restrictive—state types. These state types, which could include UTXOs, ring buffers, and statically accessible storage, are especially suited for ERC-20 tokens, NFTs, and many DeFi applications. Migrating an ERC-20 token to the new model could slash transaction fees by more than tenfold, while more complex contracts like Uniswap might not benefit equally.
Privacy becomes a primary protocol objective. Developers are evaluating how quantum-secure, intermediary-free private transactions can traverse mempools and state structures. Formal verification is elevated as a core security goal, supported by ongoing work on evm-asm. The roadmap also foresees the need for an additional virtual machine—leanISA or RISC-V—alongside the EVM, to enable programmable privacy and better scalability. In the long term, the EVM might become a compiler-level feature, with the protocol focusing directly on leanISA or RISC-V.
Buterin confirmed that incremental scaling improvements will continue. The upcoming Glasterdam upgrade is expected to deliver a significant gas limit increase, and future slot time reductions will be implemented once client optimizations ensure safety. The H-star (Hegota) upgrade will likely be Ethereum’s final major release before Lean-focused updates begin. Throughout the transition, developers aim to minimize disruption for existing applications, mirroring the successful Merge approach.
