> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cow.bleu.builders/llms.txt
> Use this file to discover all available pages before exploring further.

# Installation

> A smart contract that enables safe execution of user-specified hooks in CoW Protocol settlements

## Prerequisites

* [Foundry](https://book.getfoundry.sh/) installed
* A CoW Protocol settlement contract address for deployment

## Installation

<Steps>
  <Step title="Clone the repository">
    ```bash theme={null}
    git clone https://github.com/cowprotocol/hooks-trampoline.git
    cd hooks-trampoline
    ```
  </Step>

  <Step title="Install dependencies">
    ```bash theme={null}
    forge install
    ```
  </Step>

  <Step title="Compile contracts">
    ```bash theme={null}
    forge build
    ```

    Compilation uses Solidity 0.8.20, EVM Shanghai, with optimizer enabled at 1,000,000 runs.
  </Step>

  <Step title="Run tests">
    ```bash theme={null}
    forge test
    ```
  </Step>
</Steps>

## Deployment

### Forge Script

The constructor accepts one parameter: the settlement contract address.

```bash theme={null}
forge create src/HooksTrampoline.sol:HooksTrampoline \
  --constructor-args <SETTLEMENT_ADDRESS> \
  --rpc-url <YOUR_RPC_URL> \
  --private-key <YOUR_PRIVATE_KEY>
```

To verify on Etherscan, add `--etherscan-api-key` and `--verify` flags.

### Cannon

Cannon provides predictable addresses and multi-chain support through configuration files. The system automatically retrieves settlement addresses from the `cow-settlement` package, reducing manual configuration.

```bash theme={null}
yarn install
yarn build:cannon
yarn cannon:publish
```

<Note>
  Publishing requires 0.0025 ETH + gas fees on Optimism Mainnet.
</Note>

## Verification

After deployment, verify the contract using `cast` to check the settlement address:

```bash theme={null}
cast call <TRAMPOLINE_ADDRESS> "settlement()" --rpc-url <YOUR_RPC_URL>
```

Or verify on Etherscan with constructor argument encoding.

## Resources

* Production addresses are available at the [cowprotocol/deployments](https://github.com/cowprotocol/deployments) repository
* Next step: Review the [Usage Guide](/hooks-trampoline/usage) for integration details