On July 31, coinciding with Ethereum's tenth anniversary, Ethereum Foundation researcher Justin Drake shared a roadmap titled 'Lean Ethereum', preparing for the development of Ethereum in the next decade. The roadmap was released in the form of a blog post, with each area having only 2-3 sentences of brief description, but each element contains many condensed details. This article will delve into each part of the roadmap and examine how the Ethereum network will transform through this roadmap.
1.1 Enhancing Quantum Cryptographic Resistance
As mentioned first in the roadmap, I believe Ethereum's greatest value lies in its stability as a 'chain that has never stopped since the genesis block', which has enabled the largest institutional capital inflow to date. This achievement is due to Ethereum's prioritization of network decentralization and lightweight nodes over the past decade, a value that must be preserved to achieve Ethereum's recently announced goal of '$1 trillion security'.
This vision is backed by the arrival of the quantum computing era. Quantum computing technology is accelerating, as evidenced by Google's Willow quantum computer achieving 105 qubits, and NIST recommending phasing out existing cryptographic algorithms by 2030, with a complete transition to quantum-resistant standards by 2035. The ECDSA and BLS signatures based on elliptic curve cryptography currently used by Ethereum are vulnerable to attacks by quantum computers using Shor's algorithm, and it is well-known that sufficiently powerful quantum computers could render current cryptographic systems obsolete. The entire Web3 ecosystem has been discussing this issue for years, and Vitalik has detailed on the Ethereum research forum countermeasures that could be implemented through hard forks if a quantum computer attack occurs before upgrading to quantum-resistant cryptographic algorithms.
However, it is clear that Ethereum must eventually upgrade to quantum-resistant cryptographic algorithms. Vitalik mentioned in 2023 that this would occur during the final phase of Ethereum's long-term roadmap, 'Splurge'. There were no prior indications of which cryptographic technologies would be used or what changes would be made, but Drake's roadmap clearly proposes a radical approach of transitioning all cryptographic primitives to a hash-based system.
Regarding the quantum resistance of hash-based cryptography: while prominent quantum computing methods can effectively break public-key cryptography like RSA and elliptic curves, they are relatively inefficient at breaking hash functions. Although quantum computing can accelerate brute-force cracking speeds, enhancing security levels by increasing hash lengths can adequately address this issue. Hash-based signature schemes (e.g., SPHINCS+, Lamport) are known to be quantum-resistant. Hash-based cryptography not only offers quantum resistance but also has advantages in its simplest form in cryptography, allowing for the reconstruction of consensus layers, data layers, and execution layers.
1.2 Achieving Extremely High Scalability Through Comprehensive Chain Redesign
The second pillar of the roadmap is extremely high scalability. Drake proposed ambitious targets of 1 trillion gas per second for the Ethereum network and 1 pet gas per second for Layer 2. In terms of transaction throughput, this is equivalent to approximately 10,000 transactions per second for Ethereum and about 1 million transactions per second for Layer 2—an unimaginable performance improvement compared to Ethereum's current performance of about 30 TPS. Drake's roadmap aims to achieve radical performance improvements by redesigning Ethereum's three core layers—execution layer, consensus layer, and data layer.
1.2.1 Consensus Layer: Implementing Beam Chain
For the consensus layer, the goal is to implement the Beam Chain proposed by Drake at last year's Devcon conference. Drake pointed out that the design of the Beacon Chain prioritizes security over performance, which has created bottlenecks for performance-related updates. He believes that a complete redesign of the consensus layer is necessary to fully address the flaws in the Beacon Chain design. Additionally, he calls for the proactive adoption of rapidly evolving SNARK proofs and zkVM to at least triple the speed of block production and finalization.
Although the Beam Chain roadmap mentions multiple issues, the primary goal is to merge the multiple committees currently used in the Gasper consensus mechanism into one large committee, reducing finalization time to 12 seconds and block production time to 4 seconds. This requires extremely lightweight state validation, with SNARK proofs and zkVM playing a crucial role here. Significant changes are expected in state management and signature mechanisms, transitioning to a SNARK-based system.
Although Drake emphasized that the announcement of the Beam Chain roadmap was his proposal as an individual researcher, the release of the Lean Ethereum roadmap indicates that the implementation of Beam Chain will officially begin.
1.2.2 Execution Layer: Introducing RISC-V
Significant changes are also expected at the execution layer. Drake proposed a roadmap to completely redesign the EVM, adopting an instruction set that is friendly to SNARKs while maintaining compatibility with existing smart contracts. He mentioned RISC-V as a potential alternative execution environment, proposing the possibility of realizing a RISC-V-based execution environment that Vitalik Buterin has been discussing since 2024.
RISC-V is an open-source instruction set architecture that is much lighter than the 32/64-bit register-based architecture compared to the 256-bit stack-based architecture of the EVM. Since each RISC-V instruction can be translated into simple and predictable constraints, building an execution environment based on RISC-V can significantly shorten the proof generation time for Ethereum execution. If all executions are designed to automatically generate zero-knowledge proofs, nodes can be confident in the accuracy of state transitions without needing to re-execute them. This transition will be fully compatible with existing smart contracts, allowing developers to continue using existing tools and languages.
1.2.3 Data Layer: Overcoming Blob Limitations
Although the current blob system introduced through EIP-4844 significantly reduces L2 costs, it still has fundamental limitations. The fixed size of 128KB limits flexibility, KZG commitments are vulnerable to attacks from quantum computers, and the current target of 6 blobs per block (during the Pectra upgrade) is insufficient to meet future needs.
The Lean Ethereum roadmap addresses these limitations from multiple angles. First, it ensures quantum resistance through the aforementioned hash-based commitments compared to existing KZG. It maximizes cost efficiency by allowing variable blob sizes, enabling the Layer 2 chain to store only the exact amount of data needed. Finally, it improves data availability sampling methods, allowing nodes to verify availability without downloading the entire data, laying the foundation for a significant increase in the number of blobs.
With the announcement of Lean Ethereum, the leanroadmap.org website has also gone live, allowing users to track the implementation status of the Lean Ethereum roadmap in real-time. According to the site, the phase of promoting upgrade needs to the Ethereum community is nearing completion, with task prioritization and implementation preparations expected to be finalized by early 2026. Justin Drake estimated that the implementation of the Beam Chain roadmap could take up to 5 years, while the implementation of Lean Ethereum seems to aim for testing to be completed by early 2029. Given that Beam Chain only covers consensus changes, a new roadmap that needs to update all components of consensus, execution, and data is expected to progress at a very fast pace. The site not only tracks the aforementioned charts but also monitors detailed implementation progress of all necessary components for updates, providing visibility for the entire Ethereum community, not just developers, proclaiming that Lean Ethereum is not only a grand goal but a future that will become a reality in a few years.
The Lean Ethereum roadmap can be seen as Ethereum's response to high-performance next-generation blockchains like Solana and Sui. While these chains were designed from the outset to target high throughput, Ethereum, as a pioneer, faces challenges in radical performance improvements due to technical debt and the need to maintain decentralization and security as core values. This roadmap is significant not only because Ethereum is entering the throughput competition but also because it significantly departs from Ethereum's traditional stance by comprehensively restructuring the chain to enhance performance and security.
What impressed me most was the choice to compress the chain (to make it lean) rather than add new features during the reorganization. Typically, old systems evolve by adding new features on top of existing structures, while this roadmap takes the opposite approach—rethinking and simplifying everything. This is a bold choice to clear technical debt and prepare for new leaps.
In contrast, the post-quantum strategy announced by Sui in April last year embodies the essence of the 'Pat protocol' philosophy that later entrants can adopt. Sui plans to introduce quantum-resistant cryptography across a wide range of areas, including signature schemes, hash functions, and zkLogin, employing different cryptographic mechanisms for performance requirements of each use case, and plans careful updates to correspond immediately with existing implementations. Additionally, Sui announced a quantum-resistant cryptographic mechanism developed through internal research on the 28th, garnering attention as it is the first quantum-resistant path providing backward compatibility for EdDSA-based chains like Sui, Solana, and Cosmos. Sui is expected to upgrade so that users can achieve quantum resistance without changing wallet addresses or keys.
While introducing quantum-resistant cryptography while retaining existing implementations is expected to lead to performance declines, such as significantly increased verification times and sizes, Sui aims to mitigate this issue through techniques like batch verification optimization, prioritizing the maximum retention of existing user experience. This is possible because Sui placed a strong emphasis on performance and cryptographic compatibility from the start, minimizing potential technical issues when replacing cryptographic mechanisms. Sui's overwhelming performance compared to other chains is another reason it can adopt the Pat protocol strategy to achieve quantum resistance.
Ethereum's and Sui's quantum response strategies start from different starting points, but interestingly they share common insights. Both projects view the threat of quantum computing not merely as a technical challenge but as an opportunity to rethink the fundamentals of blockchain. Ethereum's radical redesign shows that even systems running for over 10 years can be rethought from scratch, while Sui's pragmatic approach demonstrates that innovation and stability can coexist.
A decade later, these two approaches to preparing for the quantum computing era ultimately mark the maturity of the blockchain ecosystem. The goal is no longer merely to create a 'fast chain' or 'secure chain'; each project is preparing for the future with its own philosophy and vision. This diversity enhances the resilience of the entire ecosystem and is the best preparation for an unpredictable future. Whether it is Ethereum's path or Sui's path, I look forward to them leading us to a better Web3 future.
