I'm currently using ccminer-cryptonight, with the latest release from 2014. I'm mining with a GTX 1080, and I'm just barely getting a higher hashrate than people with a way slower nVidia GPU.
Also, there have been 3 major cuda releases since 2014. Surely there are improvements in the new CUDA releases that wouldn't be that hard to take advantage of?
If nobody is developing anything at the moment, how hard would it be to do? I don't have any experience in developing mining software, but would be willing to give it a shot of anyone can point me in the right direction.