Transfer SOL privately. Private SPL tokens transfer and private swap will soon follow.

The program is fully audited by Accretion, HashCloak, Zigtur and Kriko, and verified onchain (with hash c6f1e5336f2068dc1c1e1c64e92e3d8495b8df79f78011e2620af60aa43090c5).

This project implements a privacy protocol on Solana that allows users to:

1. Shield SOL: Deposit SOL into a privacy pool, generating a commitment that is added to a Merkle tree.
2. Withdraw SOL: Withdraw SOL from the privacy pool to any recipient address using zero-knowledge proofs.

The implementation uses zero-knowledge proofs to ensure that withdrawals cannot be linked to deposits, providing privacy for Solana transactions.

• program/: Solana on-chain program (smart contract)
  • src/: Rust source code for the program
  • test/: Tests
  • Cargo.toml: Rust dependencies and configuration

• Solana CLI 2.1.18 or later
• Rust 1.79.0 or compatible version
• Anchor 0.31.1
• Node.js 16 or later
• npm or yarn
• Circom v2.2.2 https://docs.circom.io/getting-started/installation/#installing-dependencies

If you want to integrate Privacy Cash into your project, use the Privacy Cash SDK here.

1. Navigate to the program directory:

   cd anchor

2. Build the program:

   anchor build

3. Run unit test:

   cargo test

4. Run integration test:

   npm run test:sol
   npm run test:spl
   npm run test:mint-checked

5. Deploy the program to devnet:

   anchor build -- --features devnet
   rm target/deploy/zkcash-keypair.json
   cp zkcash-keypair.json target/deploy/zkcash-keypair.json
   anchor deploy --provider.cluster devnet
   
   or
   rm target
   anchor build --verifiable
   cp zkcash-keypair.json target/deploy/zkcash-keypair.json
   anchor deploy --verifiable --provider.cluster devnet
   
   or
   solana program deploy target/deploy/zkcash.so --program-id zkcash-keypair.json --upgrade-authority ./deploy-keypair.json

6. Deploy to mainnet:

   anchor build --verifiable
   
   rm target/deploy/zkcash-keypair.json
   cp zkcash-keypair.json target/deploy/zkcash-keypair.json 
   
   anchor deploy --verifiable --provider.cluster mainnet

7. Transfer the authority to multisig wallet

   solana program set-upgrade-authority 9fhQBbumKEFuXtMBDw8AaQyAjCorLGJQiS3skWZdQyQD \
   --new-upgrade-authority AWexibGxNFKTa1b5R5MN4PJr9HWnWRwf8EW9g8cLx3dM \
   --upgrade-authority deploy-keypair.json \
   --skip-new-upgrade-authority-signer-check \
   --url mainnet-beta