Privacy Protocol Cipher
Privacy Protocol Cipher is a privacy middleware toolkit for building confidential decentralized applications on EVM blockchains. It combines Zero-Knowledge proofs (Noir) and Fully Homomorphic Encryption (Zama FHEVM) to enable private, verifiable on-chain logic.
What it does
Cipher lets you build applications where sensitive data — like votes, bids, or balances — stays encrypted on-chain while still being provably correct. No one can see individual values, but everyone can verify the aggregate results.
How it works
Cipher uses two complementary cryptographic primitives:
| Layer | Technology | Purpose |
|---|---|---|
| Zero-Knowledge Proofs | Noir + Honk SNARK | Prove membership, ballot validity, and nullifier correctness without revealing identity |
| Fully Homomorphic Encryption | Zama FHEVM | Encrypt votes on-chain; tally encrypted values without decrypting individual ones |
The flow
- Membership proof — A Noir circuit proves the voter belongs to the DAO without revealing which member they are
- Encrypted vote — The vote is encrypted before submission; even the contract cannot see individual votes
- Nullifier — A deterministic hash ties each voter to each proposal exactly once, preventing double voting
- Homomorphic tallying — The contract adds encrypted votes together without decrypting them
- Final reveal — When voting ends, the aggregate tally is decrypted via KMS, revealing only totals
Available toolkits
DAO Toolkit (available now)
The DAO Toolkit provides private governance primitives:
PrivateDaoAdapter— Core adapter contract for private proposals and votingIPrivateDaoAdapter— Interface for integrating into your own DAO contractsVoteSubmissionVerifier— On-chain Honk SNARK verifier for membership proofs- Proof generation scripts — TypeScript utilities for generating ZK proofs client-side or server-side
Coming soon
Additional privacy toolkits for other use cases (private auctions, confidential transfers, etc.) are planned. The modular architecture means each toolkit can be adopted independently.
Supported networks
- Sepolia testnet — Pre-deployed contracts available now
- Ethereum mainnet — Coming soon
- L2 networks — Support for major L2s is planned
- Starknet & Solana — Cross-chain expansion on the roadmap
Next steps
- Prerequisites — Tools and knowledge you’ll need
- Installation — Add Cipher to your Hardhat project
- Contracts Guide — Integrate private voting into your DAO