Honestly, I deliberately left it vague on that point simply because, if we find the right person, I believe we can work to accommodate either way. We currently work using MySQL for data storage, PHP for some scripting, web development and data display, and R and Excel for different levels of data analysis. But if someone comes along with different preferences for languages/tools, that's not to say we could not adapt. And, likewise I would anticipate that if someone comes along with a high interest level but without the requisite experience with, say, PHP, that it could be learned from their end.
I hope by leaving it this open-ended I don't discourage people from inquiring, but I guess my point is that we are more interested in finding the right people with the right mix of skills and interest and I think some of the other details can be worked out after.