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OP Stack
Interoperability
SuperchainERC20
Interop is currently in active development and not yet ready for production use. The information provided here may change frequently.

We recommend checking back regularly for the most up-to-date information.

SuperchainERC20

The SuperchainERC20 (opens in a new tab) contract implements ERC-7802 (opens in a new tab) to enable asset interoperability within the Superchain.

Asset interoperability allows tokens to move securely across the Superchain by burning tokens on the source chain and minting an equivalent amount on the destination chain. This approach addresses issues such as liquidity fragmentation and poor user experiences caused by asset wrapping or reliance on liquidity pools.

Instead of wrapping assets, this mechanism effectively "teleports" tokens between chains in the Superchain. It provides users with a secure and capital-efficient method for transacting across chains.

Additional features:

  • Simplified deployments: Zero infrastructure cost to make your token cross-chain. Provides a consistent, unified implementation for tokens across all Superchain-compatible networks and a common cross-chain interface for the EVM ecosystem at large.
  • Common standard: Implements ERC-7802, a unified interface that can be used across all of Ethereum to enable cross-chain mint/burn functionality.

How it works

SuperchainERC20 (opens in a new tab) and SuperchainTokenBridge (opens in a new tab) work together to allow ERC-20 tokens to be transferred from one chain to the other.

The initiating message burns tokens on the source chain. The executing message then mints them on the destination chain.

Initiating message (source chain)

  1. The user (or a contract) calls SuperchainTokenBridge.sendERC20 (opens in a new tab).

  2. The token bridge calls SuperchainERC20.crosschainBurn (opens in a new tab) to burn those tokens on the source chain.

  3. The source token bridge calls SuperchainTokenBridge.relayERC20 (opens in a new tab) on the destination token bridge. This call is relayed using L2ToL2CrossDomainMessenger.

Executing message (destination chain)

  1. The user, or a relayer, sends an executing message to L2ToL2CrossDomainMessenger to relay the message.

  2. The destination token bridge calls SuperchainERC20.crosschainMint (opens in a new tab) to mint tokens for the user/contract that called SuperchainTokenBridge.sendERC20 originally.

Requirements

Application developers must complete two steps to make their tokens compatible with SuperchainERC20. Setting this up in advance ensures tokens will benefit from interop when it becomes available.

  • Grant permission to SuperchainTokenBridge (address 0x4200000000000000000000000000000000000028) to call crosschainMint and crosschainBurn. If you are using SuperchainERC20 (opens in a new tab) this is already done for you.

  • Deploy the ERC-20 contract at the same address on every chain in the Superchain. This is easiest when using create2 (opens in a new tab).

⚠️

To ensure security, you must either design the deployer to allow only a specific trusted ERC-20 contract, such as SuperchainERC20, to be deployed through it, or call CREATE2 to deploy the contract directly from an EOA you control.

This precaution is critical because if an unauthorized ERC-20 contract is deployed at the same address on any Superchain network, it could allow malicious actors to mint unlimited tokens and bridge them to the network where the original ERC-20 contract resides.

Comparison to other token implementations

SuperchainERC20 differs from other token implementations in both focus and design:

  • It implements ERC-7802, a minimal cross-chain mint/burn interface designed to establish a common standard across the EVM ecosystem.
  • It relies on the shared trust assumptions of the Superchain. All traffic originating from any chain within the Superchain is trusted because these chains share the same security standard.

Projects moving from other token implementations may need to adapt to the SuperchainERC20 specification.

FAQ

What happens if I bridge to a chain that does not have the ERC-20 contract?

The initiating message will successfully burn the tokens on the source chain. However, the executing message will fail because it attempts to call crosschainMint on a non-existent contract. Once a SuperchainERC20 contract is properly deployed on the destination chain, you can retry the executing message to retrieve your tokens.

Next steps