wasabridge

-Current Challenges

Existing cross-chain solutions rely on relayers to execute transactions on the destination chain. This results in [msg.sender] being different from the actual user.

-Why is this an issue?

Many smart contracts depend on msg.sender, preventing accurate tracking of user activities such as airdrops, social interactions, or balance queries. Furthermore, this limitation hinders the proper functionality of on-chain queries on the destination chain. Many experts, including the CTO of Paradigm, have discussed this challenge.

-Our Solution We are developing an Intents Bridge powered by EIP-7702, which ensures msg.sender is the actual user, even on the destination chain.

-Key Features

Flexibility: Allows msg.sender to remain the user on the destination chain. Traceability: Enables on-chain tracking of user data. Efficiency: As an intents-based bridge, it is faster and cheaper than existing solutions.

-Use Cases On-chain Tracking: Since msg.sender aligns with the EOA, users' on-chain activities can be tracked. Enables analytics, airdrops, and other user-centric actions. Flexible Smart Contract Development: Use the msg.sender address to execute any smart contract, e.g., social actions like follows or votes. Cross-chain Swaps: Perform fast and cost-efficient token swaps to any chain.

-Future Work

Gas Abstraction: Enable users to pay gas fees using any token. Batch Settlement: Reduce gas costs by bundling multiple settlements into a single transaction. Customizable RFQ (Request for Quotation): Implement an RFQ mechanism to determine relayers. We propose starting with a one-shot auction for small, fast bridges and gradually adopting more efficient methods, such as batch auctions, to optimize execution and scalability.

Our project combines cutting-edge technologies and innovative frameworks to create a seamless and efficient cross-chain intents bridge:

EIP-7702: This standard enables the use of user signatures to make the msg.sender on the destination chain an EOA, ensuring compatibility with existing smart contracts. Additionally, we leveraged its gas sponsorship feature to enhance the user experience by covering gas fees on behalf of the user.

ERC-7683: This was employed as the foundation for implementing cross-chain intents, allowing us to design and execute sophisticated transaction flows across multiple chains.

Intents-Framework: We used this framework for implementing solvers and facilitating settlements. Hyperlane was integral to this, as it provided the infrastructure for efficient and reliable cross-chain settlements.

By combining these technologies, we were able to address critical challenges in interoperability and create a flexible, user-friendly solution. One notable "hacky" approach was optimizing the integration of EIP-7702 and ERC-7683 to ensure minimal latency and gas costs while maintaining robust security and compatibility with existing blockchain infrastructure.