Pros
MongoDB is an exciting, fast paced, and growing company. The technical work is probably some of the most interesting out there, and my colleagues are intelligent and a pleasure to work with. The company emphasizes personal growth and cares about their employees' well being. This includes a genuine desire to do better with diversity. Over my 6 years here I have never been bored. I feel like the projects I contribute to are moving the needle for the quality of the product, and I can see the products getting better every day.
Cons
With mostly annual releases, sometimes the pace of change can feel slow. Processes sometimes drag on and robustness testing can be a productivity burden. The company still has a ways to go with diversity, as it seems every tech company does.