Code splitting
Load it when you need it. This is the earliest feature of Webpack, in fact the reason they've created it.
branch 05.1-code-splitting
It's fairly simple with Webpack.
In this branch, he added React to the app. It adds a pie chart visualisation to the To Do completion progress. It uses React with D3. This makes the dev version of bundle.js to be around 2.1MB. We want to load these libraries as late as possible.
Angular 1 not suited to code splitting
It loads all modules, components, etc at once. Not trivial.
Q&A: Prefetch or DLL plugins for Webpack
He doesn't use them, he will present an alternate solution.