ChainRoutes

One signature. Any token. Any chain.

ChainRoutes is a trustless cross-chain intent solver. Sign one intent and ChainRoutes handles the swap and bridge automatically — no more juggling between DEXs and bridges manually.

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How It Works

User signs intent
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      v
BridgeSwap verifies EIP-712 signature
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      v
Swaps tokenIn -> USDC via Uniswap V3 (source chain)
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      v
Bridges USDC cross-chain via Stargate V2 (taxi mode)
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      v
ReceiverSwap receives USDC on destination chain
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      v
Swaps USDC -> tokenOut via Uniswap V3 (destination chain)
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      v
User receives tokenOut on destination chain

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Architecture

contracts/
|-- BridgeSwap.sol              # Main solver - verifies intents, swaps, bridges
|-- destination/
|   |-- ReceiverSwap.sol        # Receives bridged tokens, swaps to tokenOut
|-- adapters/
|   |-- UniswapAdapter.sol      # Wraps Uniswap V3 swap logic
|   |-- StargateAdapter.sol     # Wraps Stargate V2 bridge logic
|-- interfaces/
|   |-- IDex.sol                # Standardized DEX interface
|-- utils/
    |-- IntentVerifier.sol      # EIP-712 intent signing and verification

Key Design Decisions

• Intent-based - users sign a typed EIP-712 struct, solver executes on their behalf
• Trustless adapters - UniswapAdapter has one immutable authorizedCaller, set at deploy and locked forever. No owner backdoors
• Set-once pattern - BridgeSwap and ReceiverSwap use a set-once setUniswapAdapter() that can never be called twice, eliminating rug vectors
• Taxi mode - Stargate V2 taxi mode for immediate cross-chain execution
• Compose messaging - swap instructions are packed into the LayerZero compose message and executed automatically on the destination chain

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Tech Stack

Layer	Protocol
Swap	Uniswap V3
Bridge	Stargate V2
Messaging	LayerZero V2
Signatures	EIP-712 + ECDSA
Framework	Foundry

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Deployments

Testnet

Contract	Chain	Address
BridgeSwap	Sepolia	0xa6D61e5B83e269E62848924E3eE617AaC580D918
ReceiverSwap	OP Sepolia	0x34654e06ACc8a3CcD7eDc3BE17182e4310473A3d

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Intent Struct

struct Intent {
    address user;           // signer
    address tokenIn;        // token on source chain
    address tokenOut;       // token wanted on destination chain
    uint256 amountIn;       // amount of tokenIn
    uint256 minAmountOut;   // slippage protection
    uint256 srcChainId;     // source chain LZ endpoint ID
    uint256 dstChainId;     // destination chain LZ endpoint ID
    uint256 deadline;       // expiry timestamp
    uint256 nonce;          // replay protection
    address dstReceiver;    // recipient on destination chain
    uint24 poolFee;         // Uniswap pool fee tier
}

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Getting Started

Prerequisites

• Foundry
• RPC URLs for Sepolia and Optimism Sepolia

Install

git clone https://github.com/yourusername/chainroutes
cd chainroutes
forge install

Build

forge build

Test

forge test

Deploy

Set up your .env file:

SOLVER_ADDRESS=0xYourAddress
SEPOLIA_RPC=https://...
OP_SEPOLIA_RPC=https://...

Import your wallet securely:

cast wallet import chainroutes-deployer --interactive

Deploy destination chain first (Optimism Sepolia):

forge script script/DeployDestination.s.sol --rpc-url $OP_SEPOLIA_RPC --account chainroutes-deployer --broadcast --verify

Then deploy source chain (Sepolia):

forge script script/DeploySource.s.sol --rpc-url $SEPOLIA_RPC --account chainroutes-deployer --broadcast --verify

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Security

• Solver fee capped at 3% (300 bps)
• All intent fields signed by user via EIP-712 - solver cannot tamper with parameters
• Nonce tracking prevents replay attacks
• Deadline prevents stale intents from being executed
• UniswapAdapter authorizedCaller is immutable - cannot be changed after deployment
• setUniswapAdapter() can only be called once on both BridgeSwap and ReceiverSwap

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License

MIT