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

# Hardhat - Compiling Contracts

> Learn how to compile your smart contracts using Hardhat on Abstract.

Smart contracts must be compiled to [Zksync VM](https://docs.zksync.io/zksync-protocol/vm)-compatible bytecode using the [`zksolc`](https://matter-labs.github.io/era-compiler-solidity/latest/) compiler to prepare them for deployment on Abstract.

<Steps>
  <Step title="Update Hardhat configuration">
    Ensure your Hardhat configuration file is configured to use `zksolc`, as outlined in the [installation guide](/build-on-abstract/smart-contracts/hardhat/installation#update-hardhat-configuration):

    ```typescript hardhat.config.ts [expandable] theme={null}
    import { HardhatUserConfig } from "hardhat/config";
    import "@matterlabs/hardhat-zksync";

    const config: HardhatUserConfig = {
      zksolc: {
        version: "latest",
        settings: {
          // find all available options in the official documentation
          // https://docs.zksync.io/build/tooling/hardhat/hardhat-zksync-solc#configuration
        },
      },
      defaultNetwork: "abstractTestnet",
      networks: {
        abstractTestnet: {
          url: "https://api.testnet.abs.xyz",
          ethNetwork: "sepolia",
          zksync: true,
          chainId: 11124,
        },
        abstractMainnet: {
          url: "https://api.mainnet.abs.xyz",
          ethNetwork: "mainnet",
          zksync: true,
          chainId: 2741,
        },
      },
      solidity: {
        version: "0.8.24",
      },
    };

    export default config;
    ```
  </Step>

  <Step title="Compile contracts">
    Compile your contracts with **zksolc**:

    <CodeGroup>
      ```bash Testnet theme={null}
      npx hardhat clean && npx hardhat compile --network abstractTestnet
      ```

      ```bash Mainnet theme={null}
      npx hardhat clean && npx hardhat compile --network abstractMainnet
      ```
    </CodeGroup>

    This will generate the `artifacts-zk` and `cache-zk` directories containing the compilation artifacts (including contract ABIs) and compiler cache files respectively.
  </Step>
</Steps>