zama @zama_fhe's fhEVM Coprocessor Three states: Public state / Off-chain state / Private state - (Public state) The state of traditional L1 blockchains is public, lacking privacy - (Off-chain state) ZK handles off-chain state computation and on-chain proof but lacks composability for off-chain states - (Private state) FHE enables fully private state computation. The private state is publicly accessible on-chain, and composability between private states can be achieved within on-chain contracts. fhEVM introduces an authorization process, where the initial contract's encrypted state can be managed via a threshold MPC protocol fhEVM Coprocessor: Running FHE smart contracts on EVM chains - When a contract calls Zama's TFHE library on L1 to perform FHE operations, L1 itself does not execute any actual FHE computation but generates a pointer to the result - The computation is then performed by off-chain servers monitoring L1 - Developers can use Solidity and the fhEVM SDK without needing cryptography expertise to build end-to-end encrypted dApps - Everything done by the coprocessor is publicly verifiable—anyone can recompute ciphertext to verify the results - The fhEVM coprocessor is initially operated by Zama, but it will be opened up later (calling all zama FHE miners!) A simple application scenario: Composable on-chain identity DID: For example, your DID contract dApp can authorize a credit contract on-chain with your permission. The DID contract outputs your private identity state information (encrypted), and the credit contract uses your DID information in ciphertext to perform risk assessment and interest rate evaluation. This showcases the privacy (encrypted state) + composability of computations between FHE EVM contracts in ciphertext state. ZK is the verification/proof engine for secrets and computation FHE is the computation engine for encrypted states