This appendix introduced SystemJS and described how it processes files and in what order, due to it being a module loader. Thereafter, the official quickstart repo was introduced. We then looked at the different parts that SystemJS either needed or problems it needed to solve. At this point, we were ready to dive into how to use SystemJS to set up an Angular application. We also looked at what core parts the Angular framework needed the SystemJs to load and in what order. Leaving this appendix, we now have a clearer understanding of what problems SystemJS solves and how it can be made to set up Angular applications. It should be noted that most Angular applications are using Angular CLI or webpack, but this is definitely a good option that will be supported for some time.