Micro-Payment NFC

This project is a full-featured Web3 payment terminal designed to simplify cryptocurrency transactions through NFC technology. It allows merchants to easily create NFC payment cards pre-encoded with customer wallet addresses, enabling customers to simply tap their NFC card on the merchant’s terminal to instantly initiate a transaction.

The system automatically connects to the correct blockchain network (Polygon Mumbai or Sepolia), displays the payment details, and requests customer approval in their wallet app. Once confirmed, the payment is processed on-chain with real-time transaction status updates, instant confirmations, and receipt generation.

Concept & Flow Design: The payment process was mapped out first — how merchants issue NFC cards, how customers tap to pay, and how the blockchain confirms transactions.

NFC Integration: Hardware with NFC read/write capability was used. The merchant interface writes the customer’s wallet address and protocol data onto NFC cards. The terminal reads this data when a card is tapped.

Blockchain Integration: Using a Web3 library (like Thirdweb v5), the system connects to Polygon Mumbai or Sepolia networks. It automatically switches the customer’s wallet to the right network and prepares the transaction.

Payment Terminal UI: A simple, responsive web app was built for merchants to create cards, input payment amounts, and monitor transaction status in real time.

Real-Time Confirmation: After a customer approves the payment in their wallet, the system listens for blockchain events to instantly show confirmations, transaction hashes, and receipts.