Uniswap V4 Hook Development

This project demonstrates how to build a custom Uniswap V4 hook using Hardhat.

Project Structure

├── contracts/
│   ├── interfaces/          # Core V4 interfaces
│   ├── BaseHook.sol        # Abstract base hook contract
│   └── FeeCollectorHook.sol # Example hook implementation
├── test/                   # Test files
├── scripts/               # Deployment scripts
└── hardhat.config.js     # Hardhat configuration

Hook Example: FeeCollectorHook

The FeeCollectorHook demonstrates a practical V4 hook that:

• Collects a small fee (0.1% by default) on each swap
• Allows the owner to adjust fee rates
• Tracks collected fees per token
• Emits events for fee collection

Key Hook Functions

beforeSwap

Called before a swap is executed. Use this to:

• Validate swap parameters
• Apply pre-swap logic
• Modify swap behavior

afterSwap

Called after a swap is completed. Use this to:

• Collect fees
• Update state based on swap results
• Emit events

Setup

1. Install dependencies:

npm install

2. Compile contracts:

npm run compile

3. Run tests:

npm run test

4. Deploy to local network:

npx hardhat node
npm run deploy