I'm trying to compile (I think) imwheel and it coughs up. So I go through the hideous list of errors and find a lot of "can't find"s. So I open the jax directory and look at the first error and find it is in jax.h. In that it includes X11/Xlib.h . So I look and can't find that on the system. So.... any idea what package I can install that will provide that header file? I've installed the X11R6 library but it doesn't seem to include this one.