Buterin Warns X Country Feature Could Put Users in Real Danger

Ethereum co-founder Vitalik Buterin caused debate this week by criticizing X’s new feature that automatically reveals a user’s country, calling it a dangerous form of forced doxing that puts crypto users at risk. His concerns were echoed by other people in the crypto industry like Uniswap’s Hayden Adams and Summer.fi CTO Andrei David. Meanwhile, a separate technical debate unfolded inside the Ethereum ecosystem when Offchain Labs pushed back on Buterin’s proposal to move Ethereum’s execution layer to the RISC-V instruction set. The Arbitrum team argued that WebAssembly (WASM) is a more flexible, secure, and future-proof choice, and warned that hardwiring RISC-V into Ethereum could lock the network into a rapidly evolving proving technology. 

Buterin Slams X for Exposing User Locations

Ethereum co-founder Vitalik Buterin joined a growing chorus of people in the crypto industry criticizing X’s newly introduced feature that automatically displays a user’s country of origin. The update was rolled out quietly over the weekend, and was presented by X’s director of product Nikita Bier as a tool to strengthen platform integrity and help users contextualize posts by knowing where they come from. However, it instead caused major backlash over what many describe as forced doxing and a serious erosion of user privacy.

Buterin initially suggested the change might provide valuable insight into how people from different regions think about global issues, but he quickly reversed course after reflecting on user concerns. He warned that even a small amount of location data could expose high-risk users to real-world harm, especially high-worth crypto holders or individuals living under restrictive governments. 

Buterin said the feature was being applied without user consent and without offering an opt-out option at launch, and called the approach “wrong” as people should not have their privacy “retroactively rugpulled with no recourse.” He also predicted that some users will inevitably find ways to fake their country of origin to avoid unwanted exposure.

Several well known people in the crypto industry have similar concerns. Uniswap founder Hayden Adams condemned the update as “psychotic,” and said that while opt-in identity disclosure is reasonable, forcing location data on millions of users crosses a line. 

Andrei David, CTO of DeFi platform Summer.fi, agreed, and argued that any feature related to sensitive personal information should default to the least revealing option. Critics believe that the sudden visibility of country-level data could help malicious actors identify wealthy individuals more easily, which could potentially increase the risk of stalking, physical extortion, or targeted attacks.

Some in the community shared practical advice for those who want to disable the feature. According to Web3 leader “Langerius,” users can navigate to settings and turn off country visibility entirely or switch from a specific country to a broader region like a continent.

Not everyone opposes the change. Supporters argue that country-level identification in large nations like the United States does little to compromise anonymity. Others, like crypto venture capitalist Nic Carter, believe the feature is important for combating political manipulation by revealing accounts that falsely claim to represent local viewpoints while operating from abroad. 

Offchain Labs Pushes Back on Vitalik’s RISC-V Plan

Meanwhile, Offchain Labs, the team behind Ethereum Layer 2 network Arbitrum, has pushed back against Vitalik Buterin’s proposal to shift Ethereum’s execution layer to the RISC-V instruction set architecture, arguing that WebAssembly (WASM) is a more resilient and future-proof foundation for the network. In a detailed Nov. 20 post on Ethereum Research, four Offchain Labs researchers said that although RISC-V currently excels at generating zero-knowledge proofs, this advantage alone does not make it the best choice for long-term smart contract execution or storage on Ethereum.

Buterin originally suggested the move in April, claiming that swapping out Ethereum’s current virtual machine bytecode for RISC-V could reduce ZK proving costs by as much as 100x in certain cases. While Offchain Labs agrees that reducing proving costs is a valuable goal, the team disputed what they described as Buterin’s “implicit assumption” that a single instruction set should serve both the purpose of delivering smart contracts to the blockchain and generating proofs for ZK virtual machines. They instead argue for a separation between what they call a “delivery ISA” (dISA) and a “proving ISA” (pISA), saying the two do not need to be unified.

Offchain Labs’ post on Ethereum Research

To back their position, the researchers revealed they are already testing a prototype that demonstrates this division. In Arbitrum’s design, WASM-based Stylus smart contracts can be ZK-proven by first compiling WASM into RISC-V and then proving the resulting RISC-V execution. This approach, they said, shows that Ethereum does not need to embed RISC-V directly into its base layer to benefit from RISC-V-based ZK proving systems.

They also questioned whether RISC-V will remain at the forefront of proving efficiency as the ZK landscape grows. Recent shifts from 32-bit to 64-bit RISC-V implementations prove just  how quickly proving technology is changing, which raises concerns that enshrining RISC-V on Ethereum Layer 1 could lock the network into a moving target. The researchers pointed to emerging WASM-based ZK virtual machines, like Ligero’s Ligetron, as examples of alternative architectures that may outperform RISC-V in the future.

Offchain Labs further pointed out that ZK proving costs have already fallen dramatically—dropping to around $0.025 per Ethereum block—reducing the urgency to optimize Ethereum around proving efficiency alone. They argued that these costs are minor compared to the gas fees and MEV earned by block builders, making the choice of ISA more about long-term flexibility than short-term savings.

Finally, they explained the practical strengths of WASM, including strong type safety, mature tooling, broad hardware compatibility, and structured code that is easy to optimize without breaking contracts. Because most Ethereum nodes do not run RISC-V hardware, adopting RISC-V at the base layer would require costly emulation.

The researchers ultimately framed WASM as a universal intermediate layer—similar to an “Internet Protocol” for smart contracts—capable of bridging the diverse languages and backend systems used across the Ethereum ecosystem.