Pros
It's a great company. Might be one of the best in Russia. The labor conditions are very good. The projects are mostly interesting and challenging. Lots of great people work there, I've made many friends while working. There's a great internal blog platform, where employees can communicate their ideas, pains, joys and be heard by colleagues and management.
Cons
By the years, Yandex has grown a lot, but it didn't learn how to use the newly acquired power properly. There's much more bureacracy now compared to 5-6 years ago. Great ideas sometimes get stuck somewhere in the decision-making and never get to life. It was totally different when I first came to Yandex: the processes were quick and ricky at times and that was whole lot of fun. Now it's more steady, slow and boring. Despite opening many offices, Yandex is absolutely HQ-centric. If you want to work on the forefront products, you have to move to Moscow. If you have ambition and want a career growth, you have to move to Moscow. All the decision-making is made there.