Ethereum founder Vitalik Buterin has announced a new network development roadmap called Lean Ethereum. In terms of significance, this phase is comparable to the transition to Proof-of-Stake (The Merge). It represents the third major iteration of the protocol, during which nearly every key part of the network will be replaced.
What is Lean Ethereum?
Lean Ethereum is not a one-time upgrade, but a set of improvements that will be implemented over three to four years. The new roadmap was published after a meeting of Ethereum researchers in Berlin, continuing April discussions with development teams. The changes will affect almost all core components: transaction verification will shift to recursive STARK proofs instead of direct re-execution, and all elements vulnerable to quantum computing will be replaced with quantum-resistant counterparts.
Priority on Privacy and Security
Buterin specifically highlighted the priority of privacy. According to him, it has ceased to be a secondary task and has become a primary goal: when designing new components, developers directly ask how private transactions without intermediaries will pass through them. The increased priority of quantum security was also emphasized. This adds a lot of work—for example, finalizing the quantum-resistant design for blobs has become urgent, a task the team has been working on for several months.
Scaling and Controversial Changes
Buterin called the changes to state management the most radical part of the plan. Consensus is forming around one approach: the current type of state will be left almost unchanged and will grow moderately. At the same time, new types of state will be added—they scale much better but are not suitable for all tasks. As an example, Buterin cited a possible network configuration by 2030: 2 TB of the current type of state and 100 TB of the new type of state. The new format will be well-suited for ERC20 tokens, NFTs, and many DeFi scenarios, but not for complex "central" objects like Uniswap contracts or on-chain order books.
Rewriting applications is not mandatory, but it will be very beneficial. For example, moving an ERC20 token to the new storage type could reduce fees by more than ten times.
Plans for the Next Five Years
Buterin added that over the next five years, there will be repeated increases in the gas limit, growth in the number of blobs, and a reduction in block time. A major gas limit increase is expected with the Glasterdam upgrade. Each scaling step, he said, depends on when it becomes safe to implement.
My analysis: Lean Ethereum is an ambitious step that could radically change the network's economics. Reducing fees by ten times for ERC20 and NFTs will make Ethereum more competitive compared to Layer 2 solutions and other L1s. However, quantum security and privacy are long-term investments that will require significant resources. The market will likely react positively, but investors should monitor implementation timelines—delays could cause temporary disappointment.