Pros
One of the hottest tech companies in Sweden, at least in the field of e-commerce and payments. If you are willing to put in the effort you have the opportunity to have a huge impact in these fields. You might be able to change things that you don't like, depending on what product you are working on. There are a lot of really talented developers, and the recruitment process is one of the best I've gone through. The ratio of females to males is very good in the company as a whole (although not among the developers).
Cons
So far it has been a bigger focus on trying to hire new developers than to listen to and try to keep the ones already hired satisfied and productive. Constant chaos and stress, the working environment encourages a short-sighted development process and reactive thinking. Deep thought is virtually impossible unless you are not at the office. Erlang-centric world-view. A constant flow of new employees and managers will certainly mean that you have to justify all design choices over and over to new people all the time. There will never time to prioritize writing some form of documentation first / instead. "Those who cannot remember the past are condemned to repeat it." The atmosphere feels more like some sort of hip media school than a typical engineering workplace, although that is changing a bit now since more and more senior people are joining.