Vitalik Buterin announced "Lean Ethereum": the third era of the network with a focus on privacy and quantum security
Ethereum founder Vitalik Buterin has unveiled an updated network development roadmap called Lean Ethereum. In terms of significance, this stage is comparable to the transition to Proof-of-Stake (The Merge) and involves replacing virtually every key component of the protocol. This is not a one-time hard fork, but a series of improvements that will be implemented over three to four years.
The roadmap was published after a meeting of Ethereum researchers in Berlin, which followed up on April discussions with development teams. Buterin emphasized that the changes will affect all core layers of the network.
Key Changes in Lean Ethereum
One of the central innovations will be the transition of transaction verification to recursive STARK proofs instead of direct re-execution. This will dramatically improve efficiency and scalability. Additionally, all elements vulnerable to quantum computing will be replaced with quantum-resistant counterparts.
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 now directly ask how private transactions will pass through them without intermediaries.
At the same time, the priority of quantum security is growing. This adds a significant amount of work—for example, finalizing a quantum-resistant design for blobs, which the team has been working on for several months, has become urgent.
The Most Controversial Change and Scaling Plans
Buterin called the changes to working with the network state the most radical part of the plan. The current state type will remain almost unchanged and will grow moderately. At the same time, new state types will be added that scale much better but are not suitable for all tasks.
As an example of a configuration by 2030, Buterin cited: 2 TB of the current state type and 100 TB of the new state type. 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 extremely beneficial. For example, migrating an ERC20 token to the new storage type could reduce fees by more than ten times.
Over the next five years, there will also be an increase in the gas limit, a rise in the number of blobs, and a reduction in block time. A major gas limit increase is expected with the Glasterdam upgrade. According to Buterin, each scaling step depends on when it becomes safe to implement.
Expert opinion: Lean Ethereum is not just another upgrade, but a fundamental restructuring of the network to meet the challenges of the next decade. The focus on privacy and quantum resilience indicates that Ethereum is preparing for institutional adoption and long-term competition with new blockchains. However, the success of this ambitious program will depend on the community's ability to maintain consensus on the most controversial issues, especially regarding network state management.