truffle.js

require('babel-polyfill');
require('babel-register');
module.exports = {
  solc: {
    optimizer: {
      enabled: true,
      runs: 200
    }
  },
  networks: {
    coverage: {
      host: 'localhost',
      network_id: '*',
      port: 8555,
      gas: 0xfffffffffff,
      gasPrice: 0x01
    },
    rinkeby: {
      host: "localhost",
      port: 8545,
      network_id: "4",
      gas: 4000000
    },
  },
};