Limit Order Book — DeFi Router

Contract Details

Categoryhybrid

Files20

Price$14.99

Tech Stack

Solidity ^0.8.24 TypeScript Express SQLite Foundry

Chains

Ethereum Arbitrum Base Optimism

Description

Off-chain limit order system with on-chain settlement. Users create signed EIP-712 limit orders off-chain (gasless), a keeper monitors and executes when market price meets the limit. Supports GTC, FOK, and partial fills.

Features

✓ EIP-712 signed orders (gasless for makers)
✓ On-chain settlement via LimitOrderSettlement.sol
✓ GTC (partial fills) and FOK (all-or-nothing) orders
✓ TypeScript keeper with SQLite-backed order book
✓ REST API for order submission and tracking
✓ Chainlink price feed integration
✓ Batch fill execution for gas efficiency
✓ Cancel single order or all orders (nonce bump)

limit-order-book.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";

/// @title Limit Order Book
/// @notice Off-chain limit order system with on-chain settlement.
contract LimitOrderBook {
    address public immutable owner;
    uint256 public constant VERSION = 1;

    event Initialized(address indexed deployer);

    constructor() {
        owner = msg.sender;
        emit Initialized(msg.sender);
    }

    // ... full implementation in purchased package
}