I need to build a cloud or a web based GPU server. A C/C++ web editor is needed to enable users to write their programs. If debugging for sequential and parallel is allowed, this will be great.
There exists at least one solution from NVidia if you are a bit flexible with the tools. Namely the Nsight™ Eclipse Edition appears to support remote dev (not a web editor, but...). For more info see:
I you'd stick to nVidia, you can possibly try project rCUDA that allows to use a CUDA-capable GPU remotely as if it was installed locally given that the host and the client computers both run the same operating system.