Unlock Faster and Safer Cross-Chain Interactions with Intents

GM Builders!

I was using a Dapp that leverages a cross-chain messaging protocol to enable seamless cross-chain transactions. At first, I was excited to see more Dapps embracing the multi-chain future, but then out of nowhere, my cross-chain transaction failed.

Naturally, I dove into debugging mode to figure out what went wrong. After checking both the source and destination chains, I found that the transaction ran out of gas on the destination chain. As a developer, I get it these things can happen when fees fluctuate between chains. But as a user, it's frustrating to face transaction failures, especially when the goal is a smooth, decentralized experience. No one wants to deal with unexpected breaks in the flow of a Dapp they're trying to use.

Problems with Cross-Chain Transactions

High Cost

Cross-chain transactions often come with significantly higher fees compared to regular on-chain transactions. The cost isn't just a flat rate it varies based on the specific chain pair involved. For instance, if you're initiating a cross-chain transaction from a network with low gas fees to one with high gas fees, you'll end up paying more on the source chain. This added complexity and unpredictability can make cross-chain interactions more expensive and less appealing for users.

Unreliable Execution

Cross-chain transactions also lack consistency and reliability. The gas fees or transaction costs on the destination chain may change before the transaction completes, leading to failures. This is particularly problematic in fast-moving markets where network congestion or fluctuating gas prices can drastically alter the fee landscape between the start and end of a transaction, resulting in an incomplete or failed transfer.

Need for Failure-Safe Mechanisms

To mitigate the risk of lost funds due to transaction failures, a robust failure-safe mechanism is essential. Without such a mechanism, users are left vulnerable to partial executions or errors, where funds could be stuck or lost across chains. A dedicated layer of protection or smart contract safeguards can help ensure that users' transactions either complete successfully or revert safely without any loss.

How cross-chain intents solve these problems

There are a few key components involved in intent-based cross-chain transactions:

1. User’s Intent

2. Off-Chain Intent Solver

3. Execution

4. Fee settlement

When a user wants to perform a transaction on a specific chain, they simply express their intent on their preferred chain. For example, if I want to stake ERC20 tokens on a protocol on Ethereum but my funds are on Base, I could either go through the tedious process of bridging, swapping and then staking or I could just express an intent to stake x amount of ERC20 tokens directly on Ethereum.

The second option sounds way more convenient, right? Let’s dive into how that process works.

User’s Intent

In the example above, my intent is simple: I want to stake tokens on Ethereum. An "intent" represents the outcome the user wants from a transaction. Instead of manually navigating complex steps, users express their intent on their preferred chain, such as staking tokens on Ethereum while holding assets on a different chain. This intent is then published to the blockchain, signaling the desired action.

Intent Solver

An off-chain actor, known as a solver, picks up the user’s intent and handles the necessary actions to fulfill it like a Wishmaster that grants your request but with a fee. Solvers continuously monitor the blockchain for published intents and spring into action once they find one. To ensure fairness and efficiency, solvers participate in auctions to win the right to fulfill user intents. Once a solver is selected, they carry out the transaction on the target chain, earning a fee for their service.

Intents-based systems need a good number of active solvers to fulfill intents at faster rates. It’s like having a large army of solvers ready to work for your protocol.

Intent Execution

Execution is the final stage where the user’s intent is fulfilled. The winning solver, after successfully winning the auction, determines the required steps to carry out the intent. This could involve bridging assets, staking tokens, or any other transaction necessary to achieve the user's desired result. The solver performs these transactions on the target chain, making sure the intent is fully executed.

Fee Settlement

Once the intent is successfully executed, solvers are compensated for their work. After providing proof of successful intent execution, the solver is paid a fee for completing the task. This ensures that solvers are properly incentivized while users’ transactions are securely handled across chains without them needing to worry about the details.

Unlike fluctuating cross-chain transaction fees, fee settlement in the case of cross-chain intents is stable. Solver gets the repayment of the fee once they successfully execute the intent on the target chain. This fee is proposed by the solver in the auction. The solver with the lowest proposed fee wins the right to execution. So there is very little chance of the failing of the transaction once picked up by a solver.

Leading cross-chain intent protocols

Uniswap & Across protocol - ERC 7683

Uniswap labs and the across protocol have joined hands to create a new standard for intent-based cross-chain communication systems. The standard consists of functions and interfaces designed specifically for intent-based cross-chain systems. There is a need for such standards as more protocols will come up and it may end up ecosystem with an unorganized and unstructured scenario where each protocol will follow a different suit of rules. If a standard is followed a common infrastructure can be established as a base for protocols to be built on.

Imagine a large solver network listening to user intents from different protocols and ready to fulfill intents. this is only possible if all protocols follow a common standard. you can learn more about it here.

Axelar

Axelar is one the leading infra providers in the cross-chain and interop world. Axelar network has solvers sitting on their network. These solvers listen to user intents and can execute intents on multiple chains at once but finalize them one by one on each network.

You can read about Axelar’s intent solution here.

Across

Across is a cross-chain messaging protocol built with intents. It makes use of intents for cross-chain value transfer. It utilizes a relayer network which is very similar to the solvers network. These relayers pick up, route, and settle the intents on the destination chain.

learn more about Across’s and Relayer network here.

Conclusion

Cross-chain transactions are powerful but often frustrating due to high fees, fluctuating costs, and the risk of failure. Intent-based systems offer a more user-friendly alternative, where users simply express their desired outcome like staking on one chain while holding funds on another, and off-chain solvers handle the rest. This approach eliminates the need for manual bridging and gas management, making cross-chain interactions smoother and less error-prone.

Standards like ERC-7683 from Uniswap and Across Protocol, along with platforms like Axelar, are leading the way in making these intent-based systems more reliable and cost-effective. With solvers competing to fulfill user intents and a standardized framework in place, cross-chain Dapps are becoming easier to use, setting the stage for a more seamless and connected multi-chain experience.