truffle-config.js

const HDWalletProvider = require('@truffle/hdwallet-provider');
require('dotenv').config()
const path = require("path");

module.exports = {
  // See <http://truffleframework.com/docs/advanced/configuration>
  // to customize your Truffle configuration!
  contracts_build_directory: path.join(__dirname, "client/src/abis"),
  networks: {
    develop: {
      host: "127.0.0.1",
      port: 7545,
      network_id: "*" // Match any network id
    },
    test: {
      host: "127.0.0.1",
      port: 7545,
      network_id: "*"
    },
    ropsten: {
      provider: () => new HDWalletProvider(process.env.PRIVATE_KEY, `https://ropsten.infura.io/v3/${process.env.PROJECT_ID}`),
      network_id: 3
    },
    avalanche_fuji: {
      provider: () => new HDWalletProvider(process.env.PRIVATE_KEY, `https://api.avax-test.network/ext/bc/C/rpc`),
      port: 443,
      chain_id:43113,
      network_id: "*",
      gas: 3000000,
      gasPrice: 225000000000
    },
    alfajores: {
      provider: () => new HDWalletProvider(process.env.ALFAJORES_PRIVATE_KEY, `https://alfajores-forno.celo-testnet.org`),
      network_id: 44787,
      gas: 4000000,
    },
    celo: {
      provider: () => new HDWalletProvider(process.env.CELO_PRIVATE_KEY, `https://forno.celo.org`),
      network_id: 42220,
      gas: 4000000,
    },
  },
  mocha: {
    reporter: 'eth-gas-reporter',
    reporterOptions: {
      excludeContracts: ['Migrations'],
      currency: 'USD',
      gasPrice: 21
    }
  },
  plugins: ['solidity-coverage', 'truffle-plugin-verify'],
  compilers: {
    solc: {
      version: "^0.8.0",    // Fetch exact version from solc-bin (default: truffle's version)
      // docker: true,        // Use "0.5.1" you've installed locally with docker (default: false)
      settings: {          // See the solidity docs for advice about optimization and evmVersion
       optimizer: {
         enabled: true,
         runs: 1500
       },
      evmVersion: "byzantium"
      }
    },
  },
};