I know really long title but that's what Unity seems to be doing...
I've created an issue for this as well with a sample project showing how to reproduce the problem at
For some weird reason Unity chokes when an open generic type is defined in one assembly and the type param is defined in a different assembly and is an internal type. Unity doesn't seem to care when both the open generic type and the type param are in the
same assembly even when the type is an internal type. The work around is to mark that type param as internal which is okay in my case, but I know if I was writing some sort of SDK that may not be okay specially if that type is supposed to be internal...
Figured I'd post it as a discussion since I know I never look at the issue tracker! :-)