Gone are the times where a Single-Page Application started with a plain white page. With Server Side Rendering, Code Splitting and Lazy Loading most frameworks provide massive performance improvements to optimize the delivery of your application to your customers. In this talk we will have a look at the Architecture of a typical React Single-Page Application and ask ourselfs how much code we need to transfer to the client to get a nearly native performance. Additionally we try out some runtime improvements for our application.