How would reverse engineering c code be side loading? You can get .deb, .rpm etc and install them on your distro as long as it supports the format, regardless of who developed the app, and honestly even if it doesn’t support the format there are ways. You can even compile the source code of more Linux apps, at least the FOSS ones, with just a few commands. If anything it would be more realistic to say you can ONLY side load on Linux