devServer.js

import app from 'server/app';
import webpack from 'webpack';
import config from './webpack.config.dev';

const compiler = webpack(config);
const NODE_PORT = process.env.NODE_PORT || 3000;
const NODE_HOST = process.env.NODE_HOST || '0.0.0.0';

app.use(require('webpack-dev-middleware')(compiler, {
  noInfo: true,
  publicPath: config.output.publicPath
}));

app.use(require('webpack-hot-middleware')(compiler));

app.listen(NODE_PORT, NODE_HOST, (err) => err ?
  console.error(err) :
  console.log(`Listening at http://${NODE_HOST}:${NODE_PORT}`));