Vitalik confirmed that Farcaster's information is not stored in the blockchain, but still defended the advantages of this project

PANews reported on March 27 that Web3 critic Liron Shapira posted on platform X, saying: "Farcaster (a Web3 social media platform) ostensibly advocates blockchain technology, but in reality only uses it for username allocation - needlessly duplicating the functions already achieved by DNS and email addresses, and doing it worse. Apart from this insincere choice that makes cryptocurrency enthusiasts see it as part of their community, 99% of the technology they are building is non-blockchain. It's an interesting experiment aimed at exploring whether adding more features to RSS can drive new product development." In response, Ethereum co-founder Vitalik Buterin said: "Individual messages ('casts') are published on the Farcaster chain, making it possible to create a standalone client. Therefore, it actually benefits from having a state machine not controlled by a single organization."

Shapira continued writing: "As I understand it, Farcaster's information is stored in central nodes without using blockchain technology; similar to how many RSS reader apps' backend functions as 'RSS central nodes'. That's why I think hyping up Farcaster as a use case for blockchain is insincere." Vitalik commented: "This deserves a response; I've asked the team to confirm some information. I previously mistakenly thought requests would be stored in one large blockchain like Filecoin’s simple version but this isn't true; requests are stored in CRDTs aiming for eventual consistency over message sets while trusting timestamps provided by senders which also allows better scalability. The only 'chain' farcaster uses is Ethereum (via Optimism). Ethereum’s purpose ‘is not just for usernames’, but also stores registration info about which accounts are allowed to send messages stored by CRDT nodes. This is crucial against spamming otherwise everyone would use it to back up their crypto hard drives or movies etcetera. Putting registry on-chain is the only way to ensure it's not controlled by a centralized entity and has resistance against Sybil attacks. Therefore, for Farcaster’s underlying network to meet its goal of being a robust, neutral tool without ongoing reliance on any single entity, registry plays a key role. Technically you could also use proof-of-work but this would be inefficient and in practice, centralized entities have too many efficiency advantages over regular users on mobiles/laptops."