A minimal, secure, open-source web app for gasless UniVoucher gift card redemption, integrated with the UniVoucher Partner Program.

• Gasless Redemption: Users redeem UniVoucher gift cards without connecting a wallet or paying gas fees
• Partner Integration: Integrated with UniVoucher Partner Program to earn 1% fees from redemptions
• Multi-Chain Support: Supports all UniVoucher-supported networks (Ethereum, Polygon, Arbitrum, Optimism, Base, BNB Chain, Avalanche)
• Secure: Uses proper cryptographic verification without storing sensitive data
• Real-time Data: Fetches live card information from UniVoucher API
• Modern UI: Clean, responsive interface with step-by-step redemption flow

1. Card Verification: Users enter card ID and secret
2. Secret Validation: Server decrypts private key to verify secret ownership
3. Gasless Redemption: Service wallet pays gas fees and executes redemption
4. Partner Fee: Earns 1% partner fee from each redemption
5. Fund Transfer: Remaining 99% goes to recipient address

Create a .env file with your actual values:

# Alchemy API Key for blockchain RPC connections
ALCHEMY_KEY=your_alchemy_api_key_here

# Your UniVoucher Partner Program wallet address (receives 1% fees)
PARTNER_ADDRESS=0x_your_partner_wallet_address_here

# Private key for the service wallet (pays gas fees for gasless redemptions)
# WARNING: Keep this secure and never share it publicly
SERVICE_PRIVATE_KEY=your_service_wallet_private_key_here

# Optional: Server port (default: 3000)
PORT=3000

⚠️ Security Note: Never commit your .env file to version control. The .gitignore file already excludes it.

1. Clone the repository:

git clone <repository-url>
cd redeem-base

2. Install dependencies:

npm install

3. Set up environment variables:

# Create .env file with your actual values
# See "Environment Variables" section above for required values
touch .env
# Edit .env with your actual keys and addresses

4. Start the server:

npm start

5. Open your browser to http://localhost:3000

For development with auto-reload:

npm run dev

Get card information by ID.

Request:

{
  "cardId": "1234567"
}

Response:

{
  "cardId": "1234567",
  "chainId": 1,
  "chainName": "Ethereum",
  "active": true,
  "status": "active",
  "formattedAmount": "1.0 ETH",
  "creator": "0x...",
  "message": "Happy Birthday!",
  "createdAt": "2025-01-01T00:00:00.000Z"
}

Verify card secret without revealing it.

Request:

{
  "cardId": "1234567",
  "cardSecret": "ABCDE-FGHIJ-KLMNO-PQRST"
}

Response:

{
  "valid": true
}

Redeem a card (gasless for user).

Request:

{
  "cardId": "1234567",
  "cardSecret": "ABCDE-FGHIJ-KLMNO-PQRST",
  "recipientAddress": "0x..."
}

Response:

{
  "success": true,
  "txHash": "0x...",
  "recipientAddress": "0x...",
  "partnerAddress": "0x...",
  "amount": "1.0 ETH",
  "explorerUrl": "https://etherscan.io/tx/0x..."
}

• Ethereum (ETH)
• Polygon (POL)
• Arbitrum (ETH)
• Optimism (ETH)
• Base (ETH)
• BNB Chain (BNB)
• Avalanche (AVAX)

• Private keys are never exposed or stored
• Card secrets are validated through cryptographic decryption
• Service wallet is isolated and only used for redemption transactions
• All blockchain interactions use established RPC providers (Alchemy)

This app is integrated with the UniVoucher Partner Program:

• Earns 1% fee from each redemption
• Partner fees are deducted from card amount (not added cost)
• Helps cover operational costs for gasless service

MIT License - Free to clone, modify, and use.

• Backend: Node.js, Express
• Blockchain: Ethers.js v5
• Frontend: Vanilla HTML/CSS/JS
• APIs: UniVoucher API
• RPC: Alchemy
• Documentation: UniVoucher MCP

This is an open-source project. Feel free to:

• Fork and improve
• Submit issues
• Create pull requests
• Use as template for your own UniVoucher integrations

This app is for educational and demonstration purposes. While functional, please review and audit the code before using in production with significant funds.

For UniVoucher-related questions: UniVoucher Documentation For app-specific issues: Create an issue in this repository