Pros
As the third full-time job in my professional career, MongoDB certainly stands out by offering me the opportunity to not only build cutting edge technology, but also do it on an enterprise scale, which is used by millions of customers worldwide. There is a lot of independence, combined with a good structure and process so that I am always aware of how the work I am doing benefits customers and the company. The company is very flexible and innovative around enabling distributed/remote work, which is evident by the fact that my team has engineers working from 4 different corners of the world.
Cons
The quick pace of innovation can sometimes lead to lack of architectural structure and intricate interactions between components, which leads to difficult to diagnose bugs. However, management is dedicated to improving the componentisation of the code base.