fhevm

FHEVM is a framework that brings data privacy to blockchain applications by using a technology called Fully Homomorphic Encryption, or FHE. In plain terms, FHE lets a computer perform calculations on encrypted data without ever decrypting it — meaning the raw information is never exposed, not even to the blockchain network processing it. FHEVM applies this to Ethereum-compatible blockchains (blockchains that support smart contracts written in a language called Solidity), so developers can build applications where transaction amounts, user balances, votes, or game moves remain completely hidden from everyone.

The framework works in two layers: on-chain smart contracts handle the encrypted state and access control logic, while a separate Rust-based coprocessor handles the heavy cryptographic computations off-chain. A key management system using multi-party computation manages the encryption keys, so no single party can decrypt data on their own. The encryption scheme is also described as quantum-resistant, meaning it is designed to withstand future quantum computers.

You would use this if you are building a decentralized application that needs genuine privacy — for example, blind auctions where bids stay hidden, confidential token transfers, private voting systems, or on-chain games that keep player moves secret until revealed. The tech stack includes Rust for the coprocessor and Solidity for the smart contracts, with deployment configurations using Helm and Docker.