KeptSecret

Kaviar: Cross-Chain Compliant Currency-Mixer

Our Team members:
Vincent - Twitter (@darmonren), Email ([email protected])

Ramon - Email ([email protected])

Bob - Email ([email protected])

We create a cross-chain compliant privacy bridge based on the paper Blockchain Privacy and Regulatory Compliance: Towards a Practical Equilibrium by Buterin et al. 2023.

Specifically we

• Use Poseidon Hash for tree hashing, nullifier hashing, and commitment construction

commitment = PoseidonHash(nullifier, 0)
nullifierHash = PoseidonHash(nullifier, 1, leafIndex)

• Use Privacy Pools to block blacklisted actors from using the protocol.

• Use Axelar to transfer commitment data between two chains.

• The living demo is at here, we now support privacy transfer assets from Polygon zkEVM to scroll testnet.

For ETH Hong Kong Hackathon

During this Hackathon, we improve our platform to support the Scroll and Polygon zkEVM.
Test case transaction below:
Cross-chain sender at Polygon zkEVM: https://testnet-zkevm.polygonscan.com/tx/0xfbf70bb619940bb0faf4a7080c2beb4d5efd0f2da5b7a3c5b80d47925525e172
Axelar Scan for cross-chain data transfer: https://testnet.axelarscan.io/gmp/0xfbf70bb619940bb0faf4a7080c2beb4d5efd0f2da5b7a3c5b80d47925525e172
Cross-chain receiver at Scroll: https://sepolia.scrollscan.com/tx/0x792ef14703c9d7405ee44df142f85585a6a9adee27fdc8b710d121ecb245b961

Workflow

Build

First, you must have the Circom 2 compiler installed. See Installation instructions for details.

The build step compiles the circuit, does an untrusted setup, generates a verifier contract, and compiles all the contracts. It could take a while at the setup step.

npm install
npm run build

Run

# run frontend-app
cd frontend && npm install && npm run dev

# run backend
cd backend && yarn install && yarn run dev

Won prizes

Congratulations to our team for clinching the 1st Prize for both Axelar Track #1 and Mantle Track #4 in the Ethereum Singapore 2023 Hackathon, Thanks to all the team members and sponsors. (Only one team won two first prizes)

Post contributors

Mohak - Twitter (@spartablock), Email ([email protected]) Arindam - Email ([email protected]) Kenneth - Twitter (@KernelKennethG), Email ([email protected])