aptswap

APT is a cross-chain atomic swap protocol enabling secure token exchanges between EVM chains (Ethereum, Arbitrum, Base, Polygon, BSC, Optimism) and Aptos blockchain using HTLC technology. Built with Node.js/TypeScript backend, Solidity/Move smart contracts, and Next.js frontend, it leverages 1inch Cross-Chain SDK for optimal routing. The protocol uses cryptographic secret-based escrow systems with time-locks, providing trustless bridging without intermediaries. Features include real-time quotes, MetaMask integration, comprehensive REST API, and support for USDC, USDT, WETH across 7+ networks.

Apt leverages 1inch's proven smart contracts and Cross-Chain SDK as its foundation for DEX aggregation and optimal routing. The protocol extends this by implementing custom HTLC (Hash Time-Locked Contract) escrow systems using OpenZeppelin contracts on EVM chains and native Move contracts on Aptos. The backend is built with Express.js/TypeScript, featuring a quote engine that integrates with 1inch's routing algorithms, an order manager for swap lifecycle, and relayer/resolver services for cross-chain execution. The frontend uses Next.js with MetaMask integration and real-time price feeds. The swap flow works by deploying escrow contracts on both chains, locking tokens with cryptographic secrets, and using a resolver service to complete the atomic swap when the user reveals the secret, ensuring trustless cross-chain token exchanges without intermediaries.