Choosing between a male and a female developer

Yes, there is: There's a lot more men than women working in tech. That alone means that it's much harder to find talented women than talented men, ergo your room full of male colleagues.

This post reads like you're doing society a favor by employing a woman. You're not. If you don't hire her then someone else will; either way, the total number of women in tech remains the same. The only reason to hire based on gender, ethnicity etc. is because it benefits you and your company. It's often portrayed as something altruistic but it really isn't.