analyse.js

// script to enable webpack-bundle-analyzer
process.env.NODE_ENV = 'production';
const webpack = require('webpack');
const BundleAnalyzerPlugin = require('webpack-bundle-analyzer').BundleAnalyzerPlugin;
const webpackConfigProd = require('react-scripts/config/webpack.config')('production');

webpackConfigProd.plugins.push(new BundleAnalyzerPlugin());

// actually running compilation and waiting for plugin to start explorer
webpack(webpackConfigProd, (err, stats) => {
	if (err || stats.hasErrors()) {
		console.error(err);
	}
});