Vitalik Proposes Deep Execution Layer Overhaul

Vitalik Buterin proposes major Ethereum execution layer changes, including binary state trees and a possible shift from EVM to RISC-V.

Ethereum co-founder Vitalik Buterin has proposed a major overhaul of the network’s execution layer as part of its scaling roadmap.

The plan targets bottlenecks in proving and execution, focusing on structural updates. Key proposals include shifting to a binary state tree and potentially replacing the EVM with RISC V architecture.

Binary State Tree Proposal

The roadmap includes EIP 7864, which replaces the current hexary Merkle Patricia Tree. The new design uses a binary tree and a more efficient hash function.

Developers including Guillaume Ballet have worked on the proposal. The binary structure reduces Merkle branch sizes.

Shorter branches lower bandwidth needs for verification. This can reduce costs for light clients and private information retrieval systems.

Buterin stated that branches could become four times shorter. This would make client side verification more viable. It would also improve zero knowledge proof efficiency.

The proposal also considers changing the hash function. Options include Blake3 or a Poseidon variant.

Blake3 may offer moderate speed gains, while Poseidon could improve prover performance further.

The proposal groups storage slots into pages of 64 to 256 slots, which may reduce gas costs for contracts accessing adjacent storage.

Many applications frequently use early storage slots, and this structure could lower execution costs.

The binary tree also reduces access depth variance, simplifies the model, and supports future state expiry metadata.

Proposed Virtual Machine Shift

The second part of the proposal concerns the Ethereum Virtual Machine. Buterin discussed replacing the EVM with a RISC V based virtual machine.

This change is described as longer term and non consensus at present. He argued that protocol complexity has increased over time.

Some developers avoid using the EVM due to perceived constraints. He stated that a new VM could restore simplicity and generality.

RISC V is an open standard instruction set architecture. Provers are often written in RISC V today. Aligning the protocol VM with prover environments could improve efficiency.

Buterin said a RISC V interpreter can be compact. He described it as only a few hundred lines of code. He stated that this is how a blockchain VM should feel.

The proposal also aims to reduce reliance on precompiles. A more efficient VM could make many precompiles unnecessary. This could streamline protocol rules and reduce special cases.

Client side proving is another focus. Users could generate proofs about contract calls locally. This aligns with broader zero knowledge integration plans.

Related Reading: Vitalik Maps Ethereum’s Fast L1 Slot Reduction Plan

Phased Deployment Roadmap

The proposal outlines a gradual transition path. The first step would allow the new VM for precompiles only.

Many existing precompiles could become code running inside the new VM. The second phase would let users deploy contracts directly in the new VM.

This would operate alongside the existing EVM. Developers could choose their preferred environment.

The final phase would retire the EVM. The EVM itself could run as a smart contract within the new VM.

This approach aims to maintain backward compatibility. Gas costs may change during the transition.

However, the roadmap suggests broader scaling efforts may offset those effects. The focus remains on efficiency and cleaner design.

Buterin stated that Ethereum would function with incremental upgrades alone. However, he presented the overhaul as a structural improvement.

The proposal frames the execution layer as central to future scalability. The roadmap connects state tree reform and VM replacement.

Both target proving efficiency and client side use cases. The proposal now enters broader discussion within the Ethereum community.