I can not really help you sadly, since I own a too recent GPU for nimcuda (which only supports up to cuda 8.x don't remember the exact number). (I don't have vector_types.h header). I don't know how to install cuda 8.x without messing with the whole system.
Can you maybe precise how you build with nvcc ? You compile with `nim cpp example.nim` and then you use nvcc on the generated C++ files ? What generation of Graphics card do you have ? Which version of cuda do you use ? Have you tried to use cuda-gdb ? Since the post is quite old, I guess you may have also asked on the Discord/IRC/Matrix/... chat. Did you get any progress on it since then? I guess only two-three people in the Nim community can answer you on Nvidia GPU related questions :(
