SuperchainERC20 Quickstart

Welcome to the SuperchainERC20 quickstart guide! In this guide, we'll cover how the token works and deployment process. Whether you're a seasoned developer or just starting out, this guide has got you covered.

What is SuperchainERC20?

SuperchainERC20 provides a standardized token implementation enabling seamless token transfers across the Superchain.

SuperchainERC20 extends the standard ERC-20 token with cross-chain mint and burn capabilities, enabling seamless interoperability across the Superchain interop cluster. This token standard implements the ERC-7802 interface to enable 1-block latency cross-chain mint/burn functionality.

How does SuperchainERC20 work?

SuperchainERC20 and SuperchainTokenBridge work together to allow ERC-20 tokens to be transferred from one chain to the other.

SuperchainERC20 cross-chain transfers require two transactions:

1. Initiate Transaction: On the source chain, tokens are burned and a cross-chain message is emitted
2. Execute Transaction: The message is relayed to the destination chain, triggering token minting

This flow ensures tokens maintain consistent total supply across the entire Superchain ecosystem and eliminates the need for liquidity pools or wrapped tokens.

Why SuperchainERC20 matters for users, token issuers, and apps on Swellchain

Superchain interop provides Swellchain with essential cross-chain capabilities that enhance the network's interoperability. When token issuers use SuperchainERC20 over a typical ER-C20 deployment it gives token issuers access to the broader Superchain network effects, ensuring your tokens can seamlessly be used by apps and users across the Superchain.

SuperchainERC20 deployment creates opportunities for:

• Enhanced Liquidity: Unified token representation across chains improves capital efficiency
• Simplified Developer Experience: Consistent API for projects building on Swellchain
• Reduced Fragmentation: Improved capital efficiency for DeFi applications across the Superchain ecosystem - one chain to rule them all

Deploying SuperchainERC20 - Quickstart

This guide provides a streamlined approach to deploying SuperchainERC20 tokens on Swellchain

Prerequisites

• Foundry toolchain
• Node.js and pnpm
• Wallet with funds on Swellchain

Install Foundry toolchain:

curl -L https://foundry.paradigm.xyz | bash
foundryup

Setup and Deployment

1. Clone the starter kit repository:

git clone https://github.com/ethereum-optimism/superchainerc20-starter.git
cd superchainerc20-starter

2. Install dependencies:

pnpm i

3. Initialize environment files:

pnpm init:env

4. Configure deployment parameters in deploy-config.toml:

[deploy-config]
salt = "your-unique-salt"  # Used for deterministic deployment
chains = ["mainnet/swell", "mainnet/op"]  # List of target chains
 
[token]
owner_address = "0xYourWalletAddress"  # Token owner address
name = "YourTokenName"  # Token name
symbol = "YTK"  # Token symbol
decimals = 18  # Token decimals

5. Update RPC endpoints:

pnpm contracts:update:rpcs

6. Deploy your token:

pnpm contracts:deploy:token

This deployment process uses Create2 to ensure your token deploys to the same address across all specified chains, a critical requirement for cross-chain functionality.

Security Considerations

For production deployments, ensure that:

1. Grant permissions to the SuperchainTokenBridge(address 0x4200000000000000000000000000000000000028) to call crosschainMint and crosschainBurn.
2. The same salt value is used across all deployments to maintain address consistency. If you do not deploy the contract to a specific destination chain, users will be unable to successfully move their tokens to that chain.
3. Token supply is properly managed across chains to prevent inflation

// Only the bridge can call crosschainMint and crosschainBurn
function crosschainMint(address to, uint256 amount) external {
    require(msg.sender == address(Predeploys.SUPERCHAIN_TOKEN_BRIDGE), "Not bridge");
    _mint(to, amount);
}

Testing Your Deployment

After deployment, verify your token functions correctly:

1. Start the local development environment:

pnpm dev

2. Use the Superchain Dev Console to mint tokens and test transfers between chains.

Verify that tokens are correctly burned on the source chain and minted on the destination chain with consistent total supply.

Advanced Integration

For projects requiring custom token behavior while maintaining cross-chain compatibility, consider:

• Extending the base SuperchainERC20 contract with additional functionality
• Implementing specific business logic through the owner interface
• Adding governance controls for managing permissions and parameters

Converting Existing ERC20 Tokens

For projects with existing ERC20 tokens, migration to SuperchainERC20 requires:

1. Creating a new SuperchainERC20 implementation
2. Deploying it deterministically across all target chains
3. Setting up a migration mechanism for existing token holders
4. Configuring cross-chain permissions correctly

This process preserves token economics while enabling cross-chain functionality.

Resources and Documentation

SuperchainERC20 enables token issuers to seamlessly access Superchain network effects. By leveraging SuperchainERC20 and Superchain interop, developers can focus on building features rather than solving complex cross-chain challenges.

• Use Supersim, a local development tool, to deploy a SuperchainERC20 or build an interop-enabled app
• Learn more about the technical architecture of Superchain interop
• Learn about how other token standards can benefit from Superchain interop