const webpack = require('webpack');
const webpackDevMiddleware = require('webpack-dev-middleware');
const webpackHotMiddleware = require('webpack-hot-middleware');
const config = require('./webpack.config');

const app = new (require('express'))();
const port = 4000;

const compiler = webpack(config);
app.use(webpackDevMiddleware(compiler, { noInfo: true, publicPath: config.output.publicPath }));
app.use(webpackHotMiddleware(compiler));

app.use((req, res) => {
  res.sendFile(`${__dirname}/index.html`);
});

app.listen(port, (error) => {
  if (error) {
    console.error(error);
  } else {
    console.info('==> 🌎  Listening on port %s. Open up http://localhost:%s/ in your browser.', port, port);
  }
});

const webpack = require('webpack');
const webpackDevMiddleware = require('webpack-dev-middleware');
const webpackHotMiddleware = require('webpack-hot-middleware');
const config = require('./webpack.config');

const app = new (require('express'))();
const port = 4001;

const compiler = webpack(config);
app.use(webpackDevMiddleware(compiler, { noInfo: true, publicPath: config.output.publicPath }));
app.use(webpackHotMiddleware(compiler));

app.use((req, res) => {
  res.sendFile(`${__dirname}/index.html`);
});

app.listen(port, (error) => {
  if (error) {
    console.error(error);
  } else {
    console.info('==> 🌎  Listening on port %s. Open up http://localhost:%s/ in your browser.', port, port);
  }
});

Change port of Async example
Change port of Async example
