truffle-config.js

// const HDWalletProvider = require('truffle-hdwallet-provider');
// const infuraKey = "fj4jll3k.....";
//
// const fs = require('fs');
// const mnemonic = fs.readFileSync(".secret").toString().trim();

module.exports = {
  networks: {
    development: {
      host: "127.0.0.1",     // Localhost (default: none)
    //   host:"172.168.3.77",
      port: 8545,            // Standard Ethereum port (default: none),// ganache-cli
      network_id: "*",       // Any network (default: none)
      gas: 67219750000,
      gasPrice: 50,
    },
  },

  compilers: {
    solc: {
      version: "0.5.15",
    //   version: ">=0.4.33 <0.6.0",    // 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: {
        optimizer: {
          enabled: true,
          runs: 200,
        },
       }
    }
  }
}