Fission

We extended the 1inch Fusion+ API to the Sui blockchain by implementing a custom resolver contracts in move language, relayer, and escrow smart contracts. Our system supports bidirectional swaps, enabling users on Sui to both initiate and fulfill cross-chain orders. We use timelocks and hashlocks within our escrow contracts to secure funds during execution. The architecture supports both full and partial order fills, allowing for flexible and efficient liquidity matching directly on-chain.

Our project extends the 1inch Fusion+ API to support the Sui blockchain, enabling users to initiate and fulfill cross-chain orders directly from Sui. To achieve this, we developed smart contracts in Move, including a custom resolver and escrow contracts. These contracts implement timelock and hashlock mechanisms to securely manage funds throughout the order lifecycle and support both full and partial order fills for flexible liquidity matching.

The relayer, implemented in Golang, serves as the backbone of cross-chain communication. Its concurrent architecture allows it to efficiently coordinate escrow deployments, secret revelations, and order fulfillment events. The off-chain component of the resolver is written in TypeScript, using Ethers.js to interact with EVM-compatible chains and the Mysten Labs Sui SDK for Sui interactions. Real-time communication between the relayer and resolver is established via WebSockets, ensuring synchronized execution across all components.

A key part of the implementation involved forking and extending the Fusion+ cross-chain order SDK, which originally only supported EVM and Solana. We introduced new logic and data structures to handle Sui-specific elements such as Orders, Addresses, and hashing algorithms. This deep integration allows Sui to participate natively in Fusion+’s cross-chain liquidity ecosystem.

The frontend is built using Vite and TypeScript, offering a responsive interface for users to create, manage, and track cross-chain orders. Overall, the project demonstrates a modular, extensible approach to integrating emerging blockchains into existing cross-chain infrastructure.