On Sunday, 21 January 2018 at 04:16:10 UTC, MHE wrote: > $ dmd hw_graphical.d You need to link in and tell the compiler where to find the library. Tru dmd -I/usr/local/GIT/whatever hw_graphical.d -L-lgtk and whatever else the library does. I haven't used gtkd so I don't know the exact thing for it, but something like that.