Applied online via yandex website for position at St.Petersburg. After a several days got a email from yandex for the first technical interview. The 1st interview was quite easy: questions about what sorting algorithms you know, two-sum array, median of 3 nos, etc.
After about a week got email for the 2nd technical interview (via skype). This one was relatively hard with 3 engineers asking question about C/C++/STL, multi-threading and algorithms.
Questions like: exception in ctor, if dtors of base classes get called,
find if a singly-linked list contains a loop, make random3() using random2(), write a smart-pointer class,
programming question about multi-threading and lock-free implementation.
Just after several days, I was invited for f2f interview in St.Petersburg. There it was a task to implement an algorithm using STL (no Internet obviously) in 4 hours. Was quite hard, though the algorithm was not that complicated (it was just you feeling a time pressure and try to code very fast). After about a week I got a email from the HR that they want to work with me but my salary expectations were rather different from theirs.. So I had to turn it down.
But, altogether, positive experience, friendly HR and interviewers ;)