CryptoUPI

Problem Statement

CryptoUPI revolutionizes cryptocurrency payments by enabling instant conversion of any crypto to real INR payments via UPI. The system uses INR-T, a fully-backed stablecoin where each token represents 1 INR deposited in our bank account. Users can deposit INR to mint INR-T tokens, trade them against USDT/other cryptocurrencies on Uniswap V4 AMM pools, and burn INR-T tokens to receive instant UPI payments to any Indian bank account.This eliminates the traditional P2P exchange problems of counterparty risk, manual matching, high fees (5-15%), and long wait times (4-8 hours). Instead, users get market-driven pricing through AMM pools, 99.9% success rates, and 2-5 second transaction times. The system provides a complete crypto-to-fiat bridge where someone holding USDT can instantly pay a merchant in INR via UPI - all in one seamless transaction.The platform addresses India's 100M+ crypto users who currently have no efficient way to use cryptocurrency for daily payments, despite India's world-class UPI infrastructure processing 300M+ transactions monthly.

Solution

CryptoUPI is built using a multi-layer architecture combining smart contracts, AMM integration, and licensed payment APIs:Smart Contract Layer: Built with Solidity using OpenZeppelin standards, featuring an ERC-20 INR-T token with controlled minting (only through verified bank deposits) and burning mechanisms. Multi-signature controls ensure security with proper access management and emergency pause functionality.Uniswap V4 Integration: Custom hooks enable seamless trading between USDT/INR-T pairs with automatic payment triggering. The AMM provides instant liquidity and market-driven pricing, eliminating manual P2P matching. Initial liquidity was seeded at 1:88 ratio (USD:INR exchange rate).Payment Infrastructure: RazorPay APIs handle real UPI transactions - generating QR codes for deposits and processing instant UPI transfers for withdrawals. This provides compliance-ready banking integration without requiring complex licensing.Backend Stack: Node.js/Express APIs manage the deposit verification flow, webhook handling for payment confirmations, and transaction state management. PostgreSQL stores user data and transaction history with real-time synchronization between blockchain events and payment status.Frontend: React/Next.js application with Web3 integration (Wagmi/Viem) for wallet connections, real-time pricing displays, and mobile-responsive design for seamless UPI experiences.Key Innovation: The automatic burn-to-pay mechanism where INR-T tokens are destroyed and trigger immediate UPI transfers, creating a trustless bridge between DeFi liquidity and traditional banking without requiring state channels or complex scaling solutions.All deployed on Base Sepolia testnet with contracts at: INR-T (0xcF4419FaA87F430fC47C6387c4598d18B978554d), Hook (0x2bD8FD6f07d3BE3003B7Df5Ff531d4879B0a5040).