Vitalik: Farcaster stores request information in CRDT to improve security and scalability

Vitalik Buterin, co-founder of Ethereum, said in response to user comments about Farcaster on the As such, requests are stored in CRDTs; they are intended to achieve eventual consistency on the message set, but trust the timestamp provided by the sender and achieve better scalability this way. The only ‘chain’ Farcaster uses is Ethereum (via Optimism). Ethereum is used ‘for more than just usernames’, it also stores registration information for which accounts are allowed to send messages stored by CRDT nodes. This is crucial for anti-spam; otherwise, everyone would be using it to back up their encrypted hard drives, movies, etc. Having the registry on-chain is the only way to make it (i) not controlled by centralized actors and (ii) resistant to Sybil attacks. Therefore, in order to meet the goals of the Farcaster base network as a robust, neutral tool without ongoing dependence on a single entity, the registry plays a key role. (technically) you could also do this with proof of work, but that would be inefficient and in practice a centralized entity would have too much in front of regular users on their phones/laptops Efficiency advantage. "