Vitalik Buterin Builds Anonymous Message Board Demo With Onchain Moderation On Aztec

Ethereum co-founder Vitalik Buterin has released a working demo of an anonymous message board built on Aztec, combining fully private posting with a built in onchain moderation system. He shared the project Sunday on X, describing it as a quickly coded version of the “anon billboard with moderation” idea he first wrote about back in 2022. The code is publicly available on his GitHub account.

How The Anonymous Billboard Works

Users deposit ETH on Ethereum’s base layer, post messages anonymously on Layer 2, and later withdraw their funds back to Layer 1. Posts carry no sender address in public data and no traceable link back to the original deposit. Buterin also noted that Aztec has now reached stage 2, the most decentralized tier on the Layer 2 maturity scale.

Built-In Content Moderation

The system includes a censor role that can flag posts as “immoral,” hiding them from the default feed and applying a time-lock penalty on the poster’s next message. A local AI daemon monitors the board, checks each post against a moderation policy stored onchain, and flags violations automatically. Posting frequency is tied to deposit size, with larger deposits shrinking the cooldown between posts. Key security properties, including rate limits, privacy, and deposit safety, have been formally verified across 70 theorems. Buterin described the project as early but already capable of meaningful functionality.