ProofPay

KYC-free payments using on-chain proof on Base network

ProofPay is a decentralized payment platform that leverages Ethereum Attestation Service (EAS) on the Base network to enable secure, verified payments without traditional KYC processes.

🌟 Key Features

• Privacy-Preserving: Use on-chain attestations instead of sharing personal documents
• Policy-Based Verification: Flexible proof requirements with trusted issuers
• Session Management: Complete lifecycle from creation to execution
• Fast & Cheap: Built on Base L2 for lightning-fast transactions with minimal fees
• Upgradeable: All contracts use UUPS proxy pattern for future improvements
• Multiple Proof Types: Support for EAS attestations, ZK proofs, and signatures

🏗️ Architecture

Smart Contracts (Solidity + Foundry)

Core Contracts:

• PolicyManager: Manages payment policies with flexible proof requirements
• SessionManager: Handles payment session lifecycle with proof verification

Key Features:

• Multiple proof types (EAS attestations, ZK proofs, signatures)
• Policy-based verification with trusted issuers
• Session lifecycle management (Pending → Verified → Executed)
• Automatic expiration and refund handling
• UUPS upgradeable proxy pattern

Backend (Python + FastAPI)

• RESTful API for user and payment management
• EAS integration service
• Web3 blockchain interactions
• Real-time transaction monitoring

Frontend (React + Tailwind CSS)

• Modern, responsive UI
• Web3 wallet integration (MetaMask, etc.)
• Real-time transaction updates
• Attestation verification interface

🚀 Quick Start

Prerequisites

• Node.js v18+
• Python 3.11+
• Foundry (for smart contracts)
• MongoDB (for backend)

Using ProofPay

1. Create a Payment Policy:

// Policy with KYC requirement
uint256 policyId = policyManager.createPolicy(
    "KYC Required",
    "Payments require valid KYC attestation",
    block.timestamp,      // Valid from now
    0,                    // No expiration
    1                     // Minimum 1 proof required
);

// Add EAS attestation requirement
policyManager.addProofRequirement(
    policyId,
    ProofType.EASAttestation,
    kycSchemaUID,
    trustedIssuer,
    true,                // Required
    30 days             // Validity period
);

2. Create a Payment Session:

// Create session with 1 ETH payment
bytes32 sessionId = sessionManager.createSession{value: 1 ether}(
    payeeAddress,
    address(0),         // Native ETH
    1 ether,
    policyId,
    block.timestamp + 7 days,  // Expires in 7 days
    "Payment for services"
);

3. Attach Proof and Execute:

// Attach EAS attestation
sessionManager.attachProof(
    sessionId,
    ProofType.EASAttestation,
    attestationUID,
    issuer,
    0                  // No expiration
);

// Verify session
bool verified = sessionManager.verifySession(sessionId);

// Execute payment
sessionManager.executeSession(sessionId);

Installation

1. Clone the repository

git clone https://github.com/yourusername/ProofPay.git
cd ProofPay

2. Install smart contract dependencies

cd contracts
forge install
forge build

3. Install backend dependencies

cd ../backend
pip install -r requirements.txt
cp .env.example .env
# Edit .env with your configuration

4. Install frontend dependencies

cd ../frontend
yarn install
cp .env.example .env
# Edit .env with your configuration

Running Locally

1. Start backend

cd backend
uvicorn server:app --reload --port 8001

2. Start frontend

cd frontend
yarn start

3. Deploy contracts (local)

cd contracts
anvil  # Start local node
forge script script/DeployBase.s.sol --rpc-url http://localhost:8545 --broadcast

📚 Documentation

• Smart Contracts Documentation
• API Reference
• EAS Integration Guide
• Development Roadmap
• Contributing Guidelines

🧪 Testing

Smart Contracts

cd contracts
forge test -vvv
forge coverage

Backend

cd backend
pytest tests/ -v --cov

Frontend

cd frontend
yarn test

🔐 Security

• All smart contracts are upgradeable using UUPS pattern
• Reentrancy protection on all payment functions
• Regular security audits (coming soon)
• Bug bounty program (coming soon)

⚠️ This project is in active development. Do not use in production without thorough security review.

🌐 Deployment

Base Sepolia (Testnet)

• Network: Base Sepolia
• Chain ID: 84532
• RPC: https://sepolia.base.org
• Explorer: https://sepolia.basescan.org
• EAS Registry: 0x4200000000000000000000000000000000000021

Contract Addresses (Testnet):

PolicyManager Proxy:  0xC879C9fe4Dd2ec91125074CE98E64b44218EB970
SessionManager Proxy: 0x4c03a6C94D75933AA7793489CFAf32b646A36887
EAS Registry:         0x4200000000000000000000000000000000000021

Base Mainnet

• Network: Base Mainnet
• Chain ID: 8453
• RPC: https://mainnet.base.org
• Explorer: https://basescan.org
• EAS Registry: 0x4200000000000000000000000000000000000021

Contract Addresses (Mainnet):

PolicyManager Proxy:  0x68ec8755100C66FB9599DF8a6a8de2006F1011cC
SessionManager Proxy: 0x6e29216BF4Ee6Ff4c1B3e3eD048B4D0d583e84Ac
EAS Registry:         0x4200000000000000000000000000000000000021

Deployment Instructions

1. Set up environment variables:

export PRIVATE_KEY="your-private-key"
export BASE_SEPOLIA_RPC_URL="https://sepolia.base.org"

2. Deploy to Base Sepolia:

cd contracts
forge script script/DeployBase.s.sol:DeployBase \
  --rpc-url $BASE_SEPOLIA_RPC_URL \
  --broadcast \
  --verify \
  -vvvv

3. Deploy to Base Mainnet:

export BASE_MAINNET_RPC_URL="https://mainnet.base.org"
forge script script/DeployBase.s.sol:DeployBase \
  --rpc-url $BASE_MAINNET_RPC_URL \
  --broadcast \
  --verify \
  -vvvv

Deployment info is automatically saved to deployments/ directory.

🤝 Contributing

We welcome contributions! Please see our Contributing Guidelines for details.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

🙏 Acknowledgments

• Ethereum Attestation Service for the attestation infrastructure
• Base for the fast and cheap L2 network
• OpenZeppelin for secure smart contract libraries
• Foundry for the blazing fast development framework

📞 Contact

• Website: proofpay.io (coming soon)
• Twitter: @ProofPay
• Discord: Join our community

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