Connext Adapter

Lucid has developed an adapter that integrates with the Connext messaging bridge to send and receive cross-chain messages.

Fees

Connext does not support on-chain fee quoting. Fees must be calculated off-chain using Connext’s SDK.

When sending or exporting a transaction from the Lucid App, Lucid automatically calculates the required fees for the transaction, including any protocol fees.

Connext does not refund excess gas fees that may be sent during the transaction.

Interfaces

Each adapter implements the following public functions:

relayMessage

function relayMessage( uint256 destChainId, address destination, bytes memory options, bytes calldata message ) external payable returns (bytes32)

Sends a message through the Connext bridge, deducts the protocol fee, and pays the required bridge fee.

• The Ether value sent by the calling contract must include both the Connext transfer fee and the Lucid protocol fee.

• Returns a bytes32 value representing the transferId assigned by Connext.

• Includes a delegate address parameter, which can be used to call Connext-specific functions on the destination chain after the message is received (e.g., forceUpdateSlippage()).

Input Params:

Type	Name	Description
uint256	destChainId	The destination chain ID.
address	destination	The destination address.
bytes	options	An abi-encoded delegate address.
bytes	message	The message to be relayed.

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calculateFee

function calculateFee(uint256 amount) public view returns (uint256)

Calculates the Lucid protocol fee based on the bridge fee provided for the Connext message transfer. Returns the fee amount in wei.

Input Params:

Type	Name	Description
uint256	amount	The eth value in wei that is passed to the Bridge to pay for the message transfer