One additional thing I’d just like to mention:
Just because Julia is cross-platform, does not mean that every package should be cross-platform too. Wayland of course only (currently?) works on Linux and some of the open source *BSDs, but that’s OK; I don’t think anyone who worked on the Wayland specifications was giving much though to Windows or OSX in the first place. Some things just work on a limited number of platforms, because that’s the intent. Microsoft is about as likely to implement the Linux kernel’s DRM (Direct Rendering Manager) as pigs are likely to fly tomorrow, so the likelihood of Wayland every working there is close to never.