If He Walks Like A Ruby Developer But Talks Like A PHP Developer, What Is He?

"I’ve interviewed many developers who applied to a position that was attached to a specific programming language, and didn’t even know that language, but I still gave my recommendation to hire them. The reason was that I felt comfortable enough with their current skill set that I knew I could not only mentor them to transition in another language, but they could become really strong. Truthfully speaking, I never once saw a negative recourse from one of those decisions (thank goodness!)."

Contractors have even more reason to identify themselves as an X developer. Most contractors get paid for what they can do "right now." They don't get paid to learn a new language or for any transitioning period. In most cases, a contractor just needs to get the job done.