You may retain the loader in a delivered application, and use it to load compiled code or any of the supplied modules at runtime. This is useful if your application's users need to load their own code into it.
However, we do not recommend using this as a means of deferring the addition of module code to your image. It is far better to deliver your application with all the modules it needs. The first benefit is that the module itself is delivered -- if you load it at runtime you cannot do this. Second, you avoid slowing your application to a halt while it loads the module. Finally, if you leave the option open of loading arbitrary code into the image, you may need to keep the entire COMMON-LISP package, which adds greatly to the size of the delivered image.