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Verify Smart Contract using Hardhat

Verifying a smart contract allows developers to review your code from within the CeloScan Block Explorer

tip

If you use Celo Composer all the configuration is done for you out of the box, all you need is the CeloScan API keys!

Prerequisites​

Before the installation steps you need to have your hardhat project initialized using the command

npx hardhat init

Make sure to have dependencies installed and the hardhat config file is importing @nomicfoundation/hardhat-toolbox

Hardhat Configuration​

Add the following configuration to the config object in hardhat.config.js.

    networks: {
        alfajores: {
            // can be replaced with the RPC url of your choice.
            url: "https://alfajores-forno.celo-testnet.org",
            accounts: [
                "<YOUR_PRIVATE_KEY>"
            ],
        },
        celo: {
            url: "https://forno.celo.org",
            accounts: [
                "<YOUR_PRIVATE_KEY>"
            ],
        }
    },
    etherscan: {
        apiKey: {
            alfajores: "<CELOSCAN_API_KEY>",
            celo: "<CELOSCAN_API_KEY>"
        },
        customChains: [
            {
                network: "alfajores",
                chainId: 44787,
                urls: {
                    apiURL: "https://api-alfajores.celoscan.io/api",
                    browserURL: "https://alfajores.celoscan.io",
                },
            },
            {
                network: "celo",
                chainId: 42220,
                urls: {
                    apiURL: "https://api.celoscan.io/api",
                    browserURL: "https://celoscan.io/",
                },
            },
        ]
    },

Verifying Contracts​

Use the following command (Make sure your contracts are compiled before verification)

Alfajores Testnet

npx hardhat verify [CONTRACT_ADDRESS] [...CONSTRUCTOR_ARGS] --network alfajores

Celo Mainnet

npx hardhat verify [CONTRACT_ADDRESS] [CONSTRUCTOR_ARGS] --network celo