I tried looking for that "Hackintosh solution" yesterday, OS X in a Domain seems quite hard to accomplish. Cant find any successful reports about running any recent OS X in HVM Xen Domain (macOS Sierra, or El Capitan at least)
Someone tried to do it with Snow Leopard, but no luck -
http://wiki.osx86project.org/wiki/index.php/Snow_Leopard_Server_on_Xen
Seen some instructions about running macOS Sierra in Virtual Box, but sadly Virtual Box can't be used in a Xen environment (and same goes for closed source VMWare)
if you have any ideas about how it could be done, please drop them here