Giulio Rebuffo, the former chief technology officer of Erigon, has joined the Ethereum Foundation to focus on applying artificial intelligence to client development. Rebuffo announced his new role on X on Friday, November 13, stating that he will work alongside technical teams and management on “applied AI x Client Dev.”
Rebuffo’s career in Ethereum began in high school when he contributed to TurboGeth, which later became Erigon. By age 17, he was one of Ethereum’s youngest core developers, and by 22, he had become Erigon’s CTO. His work emphasized prototyping features and optimizing the protocol’s speed without requiring hard forks. He also highlighted adversarial thinking as a key skill, assuming that any code he writes will be attacked.
The Ethereum Foundation has seen significant turnover this year, with at least eight high-profile exits. Researchers Julian Ma and Carl Beek resigned in May, and Tomasz Stańczak stepped down as co-executive director in February. Other notable departures include Josh Stark, Trent Van Epps, and the three leads of the Protocol cluster. Geth creator Péter Szilágyi left the previous year, and a former employee sued the foundation and co-founder Vitalik Buterin over a firing earlier in November.
Rebuffo’s hire aligns with Buterin’s advocacy for AI-written code. In March, Buterin praised an experimental AI-built client, ETH2030, which was developed in roughly six days using Claude Code for about $5,750. Buterin has argued for using AI to improve both the speed and security of code development, emphasizing the need for more test cases, formal verification, and independent implementations.