Hello, I have tried GUI a lot, for short the most practical GTK. It has a lot of solution and a screen generator, currently I carry a C ++ application in nim not only to learn but by conviction of simplicity of maintenance. As for GTK it becomes very simple to use with the builder option of gtk (GLADE) I also tested by hand the generation of code: it is not more difficult than in other language, it even appeared simpler than gtkmm and coherent but it is only my opinion. The resources used and made available go far enough I think that if you stuck @Stefan_Salewski will be happy to answer you. My projects mainly relate to management, a lot of data transfer and display, data entry, etc.
Just one last thing the manual available on GTK online is an important source and the work done to be available under nim is colossal. It's a great solution to get you started
