Tangential to OP's link, I am suprised at how easy creating Windows apps with gtkD is. I figured there would be a lot more steps/configuring/etc. [0: Video link below] Seems quicker to get started on a new app than Visual Studio + W10 SDK? (or other offical MS Libs) Then again...that's not a high bar when it comes to VS. 0: https://www.youtube.com/watch?v=lLft7ynzers&t=410s
Pretty sure he used Windows.