I'm also happily using Gtk3 (more specifically Gtkmm with C++) here. Development and coding is working fine, shipping is hard. Linux: Package Managment Window

I'm also happily using Gtk3 (more specifically Gtkmm with C++) here. Development and coding is working fine, shipping is hard. Linux: Package Managment Windows (MSYS2): Use ldd or ntlld and ship all libraries in the same directory, to save space you can ignore all icons and extra resources you don't use. MacOS (Homebrew): Similiar to Windows but more complicated with linking and signing. You can either accept XCode or avoid it completely and use command line tools.