Ethereum’s RISC-V Pivot: Vitalik Buterin Explains Why eWASM Was Abandoned
TLDR
Delays in integration combined with SNARK developments have prompted Ethereum to reconsider its eWASM strategy.
The RISC-V architecture offers superior SNARK-friendliness compared to WebAssembly-based alternatives.
Several implementations of zkEVM adopted RISC-V as standard, influencing Ethereum's pivot decision.
eWASM was originally planned to replace the defective EVM before priorities shifted to expansion.
Vitalik Buterin explains why Ethereum abandoned eWASM during a fireside discussion at Pragma Taipei in April 2025. The co-founder of Ethereum explained how the advances in SNARK technology combined with the delays in SNARK technology required an architectural change.
RISC-V turned out to be the superior choice for ensuring SNARK-friendliness throughout the network. The transition marks a significant departure from the eWASM upgrade that was originally planned to replace the existing Ethereum Virtual Machine.
The technical reason behind the architectural change
Buterin explained that eWASM was initially designed to address the fundamental shortcomings of the current eWASM.
But the extended timeline for completing the merger has created a shift in development priorities. During this time, zero-knowledge authentication technology has grown rapidly in the ecosystem.
The rise of SNARKs introduced new requirements for virtual machine architecture. RISC-V has demonstrated superior compatibility with zero-knowledge proofing systems compared to WebAssembly-based alternatives.
Many zkEVM implementations have adopted RISC-V as their foundation and established it as the industry standard.
Buterin emphasizes that SNARK-friendliness is an important factor in the architectural decision. The need for efficient zero-knowledge proofing for the WebAssembly ecosystem has surpassed previous promises.
RISC-V offers better performance characteristics for cryptographic operations essential to Ethereum's scale road map.
Broader implications for Ethereum development
The discussion with Partick at Pragma Taipei went beyond virtual machine architecture to include developer tooling improvements.
Standardization around libraries like uVM and Foundry has accelerated development cycles for new projects. However, educational resources for Solidity remain incomplete and frequently out of date.
Buterin discussed EVM improvements that complement the RISC-V transition. Updating the standard library can improve developer productivity across ecosystems.
Account Summary's native integration simplifies wallet interactions and user onboarding processes.
Additionally, the discussion includes making Oracles more native to virtual machine architectures.
Simple access to Web2 APIs can efficiently connect traditional and decentralized applications. These improvements align with RISC-V adoption by creating a more integrated development environment.
The Ethereum Foundation's role in leading these technical transitions was highlighted during the discussion.
Balancing infrastructure maintenance with building user-facing products requires strategic prioritization. Buterin acknowledged the challenges of expediting protocol improvements while effectively incorporating community feedback.
Cross-layer interoperability and light client servers represent additional areas requiring coordination alongside virtual machine changes.
The transition to RISC-V will affect how these components interact within Ethereum's expanding technology stack. Buterin concluded by noting that addressing market failures is central to the foundation's mission moving forward.
