Pros
Great people and international atmosphere. Can be challenging work. Good healthcare and benefits. Quite good bonuses (and diets) if you travel on site to clients (best case scenario you can even get quadruple salary each quarter). Lots of internal trainings and initiatives.
Cons
Low base salary compared to other IT companies in Poland. Lack of clear objectives to get promoted or otherwise progress your carrier. You need to know what is your plan for yourself, otherwise it might be frustrating. Getting promoted is a mix of hard work and some decent luck. Even then , there are periods when promotions are frozen and it does not matter at all. Except that you got better and got more skills. It is offshore and Warsaw Office is under US central, which decisions often make no sense. US management has been a big show stopper for a long time, the winds of change are happening right now and the felling is mixed.