[schoen]

I don't know how much of a practical obstacle your language skills are for communication -- I'm guessing it's not actually a significant problem -- but you might want to work on your spoken and written English in case that affects other people's perceptions of you or your own confidence (like during those oral interviews).

I think someone else's suggestion in this thread of finding non-work opportunities to talk about technology in English could be very helpful. Or even just trying to find some more people to socialize with in English sometimes.