Pros
If you want to work in a startup environment that is fast paced and where you work with some of the best and most passionate engineers, solve hard problems (both engineering and business), learn a lot and have fun at the same time, then OfferUp is the place to be. There is transparency all the way from the CEO to VP of Engineering down to the individual contributor. Important decisions are made after getting the opinions of appropriate folks and there is no shroud around the decision making process. You are encouraged to speak up and give your opinions and to not accept status quo. You also get to work with really smart and hard working folks. There are ex-employees from Microsoft, Twitter, Amazon, Google and other large companies and this creates a great melting pot where everyone can learn. Co-workers are extremely helpful and go out of the way to help you out and unblock you. There are no artificial barriers around code and everyone has the freedom to make changes in any part of the code base. There is a lot of emphasis given to improving developer productivity and there are some very smart folks who are working to improve this. !! To summarize a great place to work in !!
Cons
1. Over crowding though this should become better as we move to the new building