[packetslave]

In my experience, the actual languages you know aren't all that important. Google wants to know that you can write code well and solve problems in SOME language. If you're smart, you can learn a new language quickly.

That being said, Java and C++ ARE still the primary languages for production applications coding at Google (with Go starting to pick up speed). If you're interviewing as a software engineer, you're probably going to want to know something about object-oriented programming (even if that's in C#, Ruby, Python, etc.). A SWE candidate that ONLY knows a purely functional language is going to have an interesting time.

What you DON'T want to do is feel like you have to go out and get a "Learn Python/Java/C++ in 21 Days" book when you have 5 years of Ruby or C# experience. As long as the interviewer can understand your code, you should be fine.

I personally have interviewed several people for my group whose primary language is TCL (yes, really!), Matlab, or Perl. As long as they can walk me through their code, or even solve the interview problems using pseudocode, I won't ding their interview scores just because they don't know Python. I'm not interviewing for traditional SWE roles, though.