easy-universal-ssr.js

import express from 'express'
import routes from './routes';
import { render, build } from 'react-universal-starter';

const app = express();

const handler = build(async (req, res, stats) => {

  try {
    const html = await render(routes, stats);

    res.send(html);
  } catch (error) {
    res.json(error);
  }
})

app.get('/*', handler)


// build.js

export default (callback) => {
  const compiler = webpack([clientConfig, serverConfig])
  const hotServerMw = webpackHotServerMiddleware(compiler)
  const compressionMw = compression()

  return (req, res, next) => {
    compressionMw(req, res, next) // this may or may not be the correct usage, but it's the blueprint of what must be done
    const stats = hotServerMw(req, res, next) // we're gonna have to modify how webpackHotServerMiddleware works
    
    if (stats) return callback(req, res, next, stats)
    throw new Error('stats not ready yet') // you get the idea -- `hotServerMw` will return the stats every time it's called after the build is completed
  }
}