SuiFusion+

This project implements a cross-chain atomic swap protocol inspired by 1inch Fusion+, using smart contracts on Ethereum (Solidity) and Sui (Move). It supports HTLC-based swaps, intent-driven orders, Dutch auctions, and partial fills, with resolvers competing to fill orders as rates decrease. Orders and secrets link escrows across both chains, and security is ensured through timelocks, secret verification, resolver reputation, and off-chain relayers. All essential Fusion+ features—intent, auction, HTLC, partial fill, recovery, and resolver management—are covered by the contracts.

• This project combines Solidity smart contracts on Ethereum and Move modules on Sui to implement HTLC (hashlock/timelock) logic, enabling secure cross-chain swaps. Each chain independently enforces asset locking and unlocking, ensuring atomicity.
• Off-chain relayers continuously watch both Ethereum and Sui networks. When a swap is initiated, these relayers coordinate the secret relay and transaction submission, enabling seamless cross-chain execution. This off-chain layer is essential for bridging the two fundamentally different blockchain environments.
• On Ethereum, the Limit Order Protocol and auction logic are deployed to sepolia, handling order creation, bidding, and settlement. On sui testnet, custom Move modules mirror the escrow and hashlock/timelock logic, allowing the same atomic swap guarantees in a non-EVM context.
• We leveraged the 1inch Fusion+ architecture for intent-based orders and partial fills, adapting it to work across EVM and Move chains. Integration with Sui required custom serialization and transaction formatting, which was a notable technical challenge.
• The hackiest part was building a cross-chain relayer that can sign, submit, and confirm transactions on both EVM and Sui, handling differences in transaction finality and error handling. This relayer is the glue that makes the cross-chain swap experience seamless for users.