Ethereum co-founder Vitalik Buterin continues to surprise the community by choosing unconventional development paths instead of directly promoting ETH. This time, he presented a working prototype of an anonymous billboard built on zero-knowledge proof principles. The project, created in a "vibe coding" style (where key tasks are formulated in words and code is written by AI tools), is based on the Aztec blockchain — a platform focused on privacy and built on Ethereum's cryptographic foundation.
Concept described in 2022 finally takes shape
The idea of an anonymous bulletin board with moderation was first voiced by Buterin in a 2022 essay on zero-knowledge proofs. The concept suggested that each user could post anonymously, while moderators could remove violations without knowing the author's identity. Now this idea has been realized in three prototypes on GitHub: a token contract, a voting oracle, and the billboard itself.
The key element of the billboard is cryptographic "nullifiers" based on the poseidon2 hash function. They confirm the user's right to post and block duplicate posts while completely hiding the author. Before sending data to the blockchain, a private function checks with the associated token contract: whether the user has the right to write. The entire process is described in detail in the first post of the repository.
Return to the topic of privacy
Buterin regularly returns to privacy protection issues. Earlier this month, he warned about the revived EU Chat Control initiative, which threatens everyday cybersecurity by requiring personal correspondence to be checked for prohibited content. In his view, privacy tools need stronger protection — any concessions will result in a loss of security. His large-scale Lean Ethereum roadmap is built on similar cryptographic principles.
Buterin's usual style
A humorous post appeared on the billboard demo: the author asked why Buterin indulges in curious projects instead of developing his own coin. There is a pattern in these jokes. In 2026, Vitalik devoted almost all his time to third-party projects far removed from Ethereum's development course. Among them were a task on recognizing anonymous authorship (which was eventually solved by independent researchers) and the first chapters of a novel about decentralized governance.
Ethereum's price this year is noticeably lower than the peaks of the previous cycle, and Wall Street is much more willing to discuss ETH's bullish prospects than the co-founder's side projects. Buterin doesn't seem bothered by this: he is more interested in cryptographic experiments than public support for Ethereum. He has even suggested that he might one day release a fantasy novel under a pseudonym: the same cryptography would prove that he wrote the book, but no one would know his name.
My analysis: Creating an anonymous billboard is not just a hobby, but a strategic move. Buterin is demonstrating that Ethereum's future lies not in marketing, but in privacy technologies. If the prototype evolves into a full-fledged product, it could become a powerful driver for implementing zk-proofs in real-world applications. For now, however, the market expects concrete steps from him on scaling the network, not experiments.