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Deploy assets using SuperchainERC20

Issuing new assets with SuperchainERC20

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Interop is currently in active development and not yet ready for production use. The information provided here may change. Check back regularly for the most up-to-date information.

This guide explains how to issue new assets with the SuperchainERC20 and bridge them effectively using the SuperchainERC20Bridge. If you want more information about the SuperchainERC20 standard, see our SuperchainERC20 standard explainer

Note that bridging assets through the Superchain using SuperchainERC20 never affects the total supply of your asset. The supply remains fixed, and bridging only changes the chain on which your asset is located. This keeps the token's total amount the same across all networks, ensuring its value stays stable during the move and that the SuperchainERC20 retains a unified, global supply count.

Steps to issue and bridge assets

Deploy the SuperchainERC20 Token Contract

To ensure fungibility across chains, the SuperchainERC20 assets need to have the same contract address on all chains. Achieving this requires deterministic deployment methods, such as:

  • Create2Deployer: A smart contract that enables deploying contracts with predictable addresses.
  • OptimismSuperchainERC20Factory: A factory contract designed for L1-native tokens to ensure uniform deployments across chains.

There are many ways to do this (opens in a new tab), but here's an example smart contract to start (opens in a new tab). For an in-depth guide on how to deploy a SuperchainERC20 use the SuperchainERC20 Starter Kit (opens in a new tab).

By deploying assets at identical addresses across multiple chains, we abstract away the complexity of cross-chain validation.

Implement the IERC7802 interface

Implementations of SuperchainERC20 will be required to implement the IERC7802 (opens in a new tab) interface, that includes two external functions and two events.

The interface defines two functions for bridging:

  • sendERC20: Initializes a cross-chain transfer of a SuperchainERC20 by burning the tokens locally and sending a message to the SuperchainERC20Bridge on the target chain using the L2toL2CrossDomainMessenger. This ensures that asset supply remains constant, as sending an asset moves it from one chain to another without creating additional supply.
  • relayERC20: Processes incoming messages from the L2toL2CrossDomainMessenger and mints the corresponding amount of the SuperchainERC20.

Here's an example implementation of the SuperchainERC20Bridge (opens in a new tab)

Next steps

How to transfer a SuperchainERC20SuperchainERC20 best practices