Pros
The systems are well-built (if eccentric), the coffee is good and the colleagues are all very, very smart, nice and motivated. It's possible to get things done in weeks or months, as opposed to years (especially compared to other companies). The atmosphere **seems** really nice. The compensation is good and the office is also pretty nice.
Cons
There are a TON of politics going on underneath the surface that the naive and junior members simply don't see. If you end up getting anywhere near this -- or end up irritating some of the senior/"inner circle" people, prepare to experience some very cold shoulders and very, very nasty politics. There are basically 3 groups at Adyen: the board, the technical/sales "old guard" and another group who is somewhat newer and trying to change Adyen. Not all of the board/direction seems to know what's actually happening on the workfloor. Lastly, working at Adyen will not help your technical career, especially if you stay for longer than 3 years. While there is some innovation, the technical old guard has been doing things the same way for the last 10 years and is not prepared to change. Staying at Adyen for more than 3 years means that you've been paid very well for 3 years but have lost 2 years of your career. Turnover is very high, by the way. It seems like roughly 1-4 people quit or is fired every month.