The usual import declaration does not work out of the box if we use NPM + React + Webpack because React is not a peer dependency of Golden Layout.
import GoldenLayout from 'golden-layout'
Instead, we need to first shim the module by adding React and ReactDOM as global variable. One way to do it is to use imports loader.
const GoldenLayout = require('imports?React=react&ReactDOM=react-dom!golden-layout')