Technical FAQ

Find quick solutions to some of the most frequently asked questions about Across Protocol.

Should I use the API versus App SDK to integrate Across?

We recommend using the App SDK for the easiest way to integrate Across into your dApp.

What is the behavior of ETH / WETH in transfers?

Depending on the context, Across will sometimes send a user ETH and sometimes send a user WETH.

• If the input asset is ETH, and the recipient is an EOA, the EOA will receive ETH

• If the input asset is ETH, and the recipient is a contract, the contract will receive WETH (not ETH)

• If the input asset is WETH, and the recipient is an EOA, the EOA will receive ETH (not WETH)

• If the input asset is WETH, and the recipient is a contract, the contract will receive WETH

How do I deposit using ETH instead of WETH?

To deposit ETH, or the native token for a network, set msg.value = inputAmount. To deposit WETH, set msg.value = 0. When depositing ETH or WETH, the inputAmount should be the same and the inputToken should be the WETH address for the current chain.

While bridging, funds got deducted from my wallet on origin chain but I haven't received them on destination chain yet.

If a deposit wasn't filled, the lifecycle of the deposit can be tracked using the status API and refunds are issued once a deposit expires. Note: refunds are only issued on mainnet deposits.

What is the recommended fillDeadline to be used while making a deposit to the Across SpokePool contracts?

Recommended fillDeadline to be used while making a deposit is 6 hours from the time of deposit. This ensures the best experience for the user specially in tricky situations where a deposit is being slow filled.