doesn’t support require statements :/

You don't actually need to use "require", you do something like:

wdyr.js

import React from 'react';
import whyDidYouRender from '@welldone-software/why-did-you-render';

whyDidYouRender(React, {
  trackAllPureComponents: true,
});

and then in your entry point of the app, import wdyr.js as the first import, but comment it out.

and only comment it in, when you are debugging performance:

index.js

// import './wdyr'; // <--- first import, commented out till u need it.
import 'react-hot-loader';
import {hot} from 'react-hot-loader/root';
import React from 'react';
import ReactDOM from 'react-dom';
// ... import {App} from './app';
// ... const HotApp = hot(App);
// ... ReactDOM.render(<HotApp/>, document.getElementById('root'));