Flashbots, an Ethereum R&D firm, has open-sourced a new block builder operating in a trusted environment, in this case a private mempool, on Ethereum’s Sepolia testnet, according to a press release shared exclusively with CoinDesk.

The research that Flashbots details will allow blocks to be built without revealing data on users’ transactions, a step toward enhancing privacy.

Block builders are specialized third-party participants who construct blocks based on optimizing transactions. Block builders offer those blocks to relays, like the relay Flashbots runs for MEV-Boost, in order to extract extra revenue made from reordering or including certain transactions.