Base Bridge Contracts

A cross-chain bridge implementation that enables seamless message passing and token transfers between Base and Solana.

Contract Addresses

• Base Mainnet Bridge: 0x3eff766C76a1be2Ce1aCF2B69c78bCae257D5188
• Base Sepolia Bridge: 0x01824a90d32A69022DdAEcC6C5C14Ed08dB4EB9B

Overview

The Base Bridge contracts facilitate bidirectional communication between Base and Solana. The system allows:

• Receiving and executing calls sent from Solana
• Transferring tokens between Base and Solana
• Creating wrapped versions of Solana tokens on Base

Architecture

Core Contracts

• Bridge: Main contract that receives calls from Solana and manages message execution via Twin contracts. Bridge is also the entrypoint for sending messages to Solana
• Twin: Execution contract specific to each Solana sender pubkey that processes calls from the bridge
• CrossChainERC20: ERC20 token implementation that can be minted/burned by the bridge for cross-chain transfers
• CrossChainERC20Factory: Factory contract for deploying wrapped tokens representing Solana tokens on Base

Prerequisites

Required Tools

• Foundry
• Make

Environment Setup

1. Install dependencies:

make deps

2. Set up wallet account:

# Create or import account for testnet deployments
cast wallet import testnet-admin --interactive

3. Ensure this account has enough ETH to pay for gas.

Development

Building

forge build

Testing

forge test
make coverage

Creating Wrapped Tokens

Create wrapped versions of Solana tokens:

# Create wrapped SPL token (requires setting environment variables first)
# Set REMOTE_SPL as bytes32 representation of SPL mint pubkey on Solana
# Set TOKEN_NAME and TOKEN_SYMBOL for the wrapped token
make create-wrapped-spl

Custom token creation:

BRIDGE_ENVIRONMENT=alpha TOKEN_NAME="MyToken" TOKEN_SYMBOL="MTK" REMOTE_TOKEN=0x1234... forge script CreateTokenScript --account testnet-admin --rpc-url $BASE_RPC --broadcast -vvvv

Operations

Bridging Tokens to Solana

Bridge various token types from Base to Solana:

# Bridge SOL (native) to Solana
make bridge-sol-to-solana

# Bridge SPL tokens to Solana
make bridge-tokens-to-solana

# Bridge ERC20 tokens to Solana
make bridge-erc20-to-solana

# Bridge ETH to Solana
make bridge-eth-to-solana

Custom bridging:

BRIDGE_ENVIRONMENT=alpha LOCAL_TOKEN=0x123... REMOTE_TOKEN=0x456... TO=0x789... AMOUNT=1000000 forge script BridgeTokensToSolanaScript --account testnet-admin --rpc-url $BASE_RPC --broadcast -vvvv

• LOCAL_TOKEN: address of ERC20 token on Base
• REMOTE_TOKEN: bytes32 representation of SPL mint pubkey on Solana (0x069be72ab836d4eacc02525b7350a78a395da2f1253a40ebafd6630000000000 for native SOL)
• TO: bytes32 representation of Solana pubkey receiver (this is your Solana wallet address if bridging SOL and it should be your associated token account if bridging into an SPL token)
• AMOUNT: The amount of Base tokens to bridge in wei