What do you mean by recompiling SCSS on the server? Do you mean compiling files after making style changes? Or do you want to serve different files depending on, for example, a page parameter? In the first case, you can compile the files using e.g. Dart Sass and replace the CSS files with new ones. We use dart sass in our UI kit. Unfortunately, if you want to serve styles dynamically depending on some parameter, I am not able to suggest which tool will work best. We have no experience in this. The choice of tool also depends on the framework you use.