LYRA QR Merchant Payment System is a blockchain-based payment platform that lets merchants receive LYRA token payments instantly via QR codes.

• Government distributes LYRA tokens to registered users.

• Merchants generate QR codes with payment details.

• Users scan and pay securely, directly on the blockchain — no banks or middlemen.

Built for the Polygon network (Chain ID: 137), it integrates with LyraToken and LyraOtcSeller smart contracts for merchant verification, token transfers, and swaps.

Generate QR codes containing:

• 🏷 Merchant address
• 💰 Payment amount
• 📝 Extra metadata

• Users scan the merchant’s QR code, verify details, and pay using LYRA tokens directly on-chain.

• Directly distribute LYRA tokens to citizens’ wallets.

Seamless interaction with:

• LyraOtcSeller for merchant verification, token swaps, and transfers
• LyraToken ERC-20 contract for token balance management

• Currently deployed on Polygon (Chain ID: 137) but adaptable to other EVM-compatible networks.

• Wallet balances are shown in MYR and USD using live exchange rate APIs.

• Frontend: Next.js 14 (App Router), TailwindCSS, Framer Motion, Material UI, PWA Notifications
• Blockchain: Polygon (EVM), Scaffold-ETH, Wagmi, Viem
• Wallet: RainbowKit, Web3Auth
• QR Code: react-qr-code (generation), @zxing/browser (scanning)
• Smart Contracts:
  • LyraOtcSeller – merchant verification & OTC swaps
  • LyraToken – ERC-20 LYRA token

• Node.js v18+
• Yarn or npm
• Browser with MetaMask or WalletConnect
• Access to Polygon Network (Chain ID: 137)

git clone https://github.com/Tianweiii/lyra.git
cd lyra

yarn install
# or
npm install

• Create a .env.local file in the root directory:

WEB3_AUTH_CLIENT_ID = WEB3_AUTH_CLIENT_ID_EXAMPLE
NEXT_PUBLIC_VAPID_PUBLIC_KEY = NEXT_PUBLIC_VAPID_PUBLIC_KEY_EXAMPLE
VAPID_PRIVATE_KEY = VAPID_PRIVATE_KEY_EXAMPLE
NEXT_PUBLIC_SUPABASE_URL = https://example.supabase.co
NEXT_PUBLIC_SUPABASE_ANON_KEY = NEXT_PUBLIC_SUPABASE_ANON_KEY_EXAMPLE

yarn start

Read Functions 📖

• isMerchant(address merchant) → Checks if the address is registered as a merchant.
• priceUsdtPerNative() → Returns MATIC price in USDT.
• lyraPerUsdt() → Returns LYRA price in USDT.
• balanceOf(address account) → Returns LYRA token balance for an address.

Write Functions 📝

• transfer(address to, uint256 amount) → Transfers LYRA tokens.
• merchantSwapLyraToUsdt(uint256 lyraAmount, uint256 minUsdt) → Swaps LYRA for USDT.
• merchantSwapLyraToNative(uint256 lyraAmount, uint256 minNative) → Swaps LYRA for MATIC.

Deployed Smart Contract (LYRA TOKEN) 📝 [https://polygonscan.com/address/0xc11bd7b043736423dbc2d70ae5a0f642f9959257#events]

Deployed Smart Contract (LyraOtcSeller) 📝 [https://polygonscan.com/address/0x5265bccc8ab5a36a45abd2e574e6fa7f863e5c2e#writeContract]

We welcome contributions! See CONTRIBUTING.md for guidelines.

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

🌐 Website: Lyra
🐞 GitHub Issues: Report Issues