Zescrow

Zescrow (for zero-knowledge escrow) is a trust-minimized, chain-agnostic implementation of an escrow program using the RISC Zero zkVM as the zero-knowledge prover/verifier.

[!WARNING]

This project is not audited, and it's currently under active development. Until v1.0, please do not deploy in production.

Goals

1. Privacy-Preserving: reveal only necessary transaction details to counterparties
2. Chain-Agnostic: deploy same escrow logic across L1s/L2s via lightweight agents
3. Dispute Minimization: cryptographic proof of condition fulfillment preempts conflicts

Core Features

• ZK proving/verification of cryptographic conditions e.g., hash-lock, Ed25519 signature over a message, etc.
• Chain-agnostic ZK verification via RISC Zero receipts.
• Solana programs and EVM smart contracts in /agent.

Architecture

Project Structure

• agent (Contains chain-specific escrow programs/smart contracts)
• client (Contains the RISC Zero guest and host, as well as mechanisms for executing on-chain agent actions)
• core (Main library that exposes types and functionality for the client)
• templates (Contains escrow_params.json, escrow_metadata.json, escrow_conditions.json; these are files that specify escrow parameters/inputs, escrow transaction output, and optional cryptographic conditions for the "Finish" command, respectively.)

High-Level Flow

1. Build and deploy a chain-specific agent (via the /agent).
2. Specify the parameters of the escrow (via the /templates/escrow_params.json).
3. Create an escrow transaction (via the client).
4. To release an escrow, execute the Finish command of the client.
5. To cancel/refund an escrow, execute the Cancel command of the client.

Usage

Prerequisites

1. Please ensure that rustup is installed. The rust-toolchain.toml file will be used by cargo to automatically install the correct version.

2. Install the risc0-toolchain, since the prover of the zescrow-client requires it.

End-to-End Demo

1. Clone the repository:

   git clone https://github.com/maatlabs/zescrow.git
   cd zescrow

2. To create an escrow end-to-end on Ethereum (and other EVM-compatible chains), please follow the ethereum-demo.

3. To create an escrow end-to-end on Solana, please follow the solana-demo.

Contributing

Thank you for considering contributing to this project! All contributions large and small are actively accepted.

• To get started, please read the contribution guidelines.

• Browse Good First Issues.

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this codebase by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.