Because our service, Filer.io, currently supports Rails. However, Node.js support is coming really soon and Node projects will be welcome in the next contest.
BTW, what is your technology of choice?
Ah, makes sense. Django is my preference though I work with PHP (Zend Framework) professionally as nothing else (besides .NET) employs where I live :-(
Thanks for sharing, we are looking forward to expand to PHP and Python as soon as possible.