Ethereum unveils Lean roadmap focusing on quantum safety

Ethereum co-founder Vitalik Buterin has unveiled a comprehensive, multi-year technical roadmap for the network, outlining a sweeping set of upgrades he calls "Lean Ethereum." Announced on July 4, 2026, the plan charts a course for the protocol's evolution through 2029, with changes comparable in scale to the network's 2022 transition to proof-of-stake.

The initiative aims to overhaul nearly every core component of Ethereum over the next three to four years. Central to the plan is a sharp increase in priority for quantum resistance, with Buterin stating that finalizing a quantum-safe solution for data blobs has become "urgent." The roadmap calls for replacing all quantum-vulnerable cryptography across the protocol with hash-based schemes designed to withstand future quantum computers.

Privacy is also being elevated from an application-layer feature to a first-class goal integrated into the base protocol, affecting areas like mempool and state tree design. To improve scalability and efficiency, the plan proposes adding new, restrictive state types alongside the existing dynamic state. By 2030, this could allow Ethereum to manage up to 100 terabytes of new state data, with...