PayperPlane is a browser extension that enables crypto payments on ANY website that accepts card payments, even if the merchant doesn't support cryptocurrency.

• Replaces card input - No more typing card numbers, expiry dates, or CVV
• One-click crypto payments - Simply send crypto through the plugin
• Privacy first - No financial data shared with merchants
• Works everywhere - No merchant integration required

1. Detects payment forms on any website
2. Injects wallet connector for crypto payments
3. Processes crypto payment and generates virtual card in parallel
4. Completes payment without card input needed

The Magic: Any website with card payment forms becomes crypto-compatible instantly!

Browser Extension ←→ Smart Contract ←→ Backend API ←→ Lithic API
     ↓                    ↓                ↓              ↓
Detects Forms      Handles Funding   Processes Events  Generates Cards
Injects UI         Stores Events     Monitors Chain    Virtual Cards
Wallet Connect     Admin Controls    Crypto Conversion Payment Processing

crypto-bnb/
├── extension/          # Browser extension (Chrome/Edge/Brave)
├── evm/               # Smart contracts (Solidity)
├── backend/           # Backend API (Python/FastAPI)
├── payperplane-react/ # Landing page (React/Vite)
└── shared/            # Shared TypeScript types

• Frontend: TypeScript, Chrome Extension Manifest V3, WAGMi, React, Vite
• Smart Contracts: Solidity 0.8+, Foundry, OpenZeppelin, Solady
• Backend: FastAPI (Python), UV package manager
• Package Manager: Bun

• Node.js 18+ and Bun
• Foundry (for smart contracts)
• Python 3.9+ and UV (for backend)
• MetaMask or compatible Web3 wallet

1. Clone and install dependencies

   git clone https://github.com/yourusername/crypto-bnb.git
   cd crypto-bnb
   bun install
   cd evm && forge install
   cd backend && uv sync

2. Build the extension

   bun run build-extension

3. Deploy smart contracts

   cd evm
   forge script script/DeployCryptoBnB.s.sol --rpc-url $RPC_URL --broadcast

4. Start the backend

   cd backend
   uv run fastapi dev main.py

Address: 0xc6BB3C35f6a80338C49C3e4F2c083f21ac36d693

Networks:

• BNB Smart Chain: https://bscscan.com/address/0xc6bb3c35f6a80338c49c3e4f2c083f21ac36d693
• CELO: https://celo.blockscout.com/address/0xc6bb3c35f6a80338c49c3e4f2c083f21ac36d693
• Moonbeam: https://moonbeam.moonscan.io/address/0xc6bb3c35f6a80338c49c3e4f2c083f21ac36d693
• TAC (TON): https://explorer.tac.build/address/0xc6bb3c35f6a80338c49c3e4f2c083f21ac36d693

Features: ERC20 support, native token payments, Chainlink price feeds, access control, reentrancy protection

1. Build the extension

   bun run build-extension

2. Install in Chrome/Edge/Brave

   • Go to chrome://extensions/
   • Enable "Developer mode"
   • Click "Load unpacked" → select dist/extension/

3. Test

   • Navigate to any e-commerce site
   • Extension should detect payment forms
   • Click extension icon to connect wallet

• Smart contracts use battle-tested libraries (OpenZeppelin, Solady)
• Role-based access controls and reentrancy protection
• Secure wallet integration without exposing private keys
• Backend validates all blockchain events

We welcome contributions! Please see our contributing guidelines for code style, testing requirements, and pull request process.

MIT License - see the LICENSE file for details.

PayperPlane - Bridging the gap between crypto and commerce, one transaction at a time. 🚀