Well, mingw is what's used by most Nim devs. on Windows so having support for that will be useful.
Meanwhile, here's a Nim wrapper for openwl, preprocessed with nimterop and wrapped by c2nim. It compiles fine. Needed some minor edits before and after but nothing major. However, given I don't have VS, no way to test if it actually works. I tried compiling the cpp files with mingw but ran into all sorts of issues. [http://ix.io/1Gfe/nim](http://ix.io/1Gfe/nim) As for Scintilla, or any other third-party component, it needs to be easy to bring it into openwl, especially since it's the same MFC behind the scenes, or GTK/Cocoa. If everything needs porting to the framework, will make it quite difficult to get acceptance since the standard only offers so much.