Pros
Great co-workers. Office culture is fun and casual, but intense and driven. Amazing flexibility in working hours and vacation time. "Get stuff done," attitude. The company is growing very fast, so there is tons of responsibility up for grabs. Very meritocratic. Software-specific: Awesome team. Great problems to work on. Massive amount of freedom and flexibility about what you get to work on.
Cons
Standard start-up cons. Growing pains. Occasional difficulties arising from an attempt to keep a "flat" company structure: sometimes it would be better to have more official decision makers that table arguments which everyone feels entitled to (and actually has a right to) participate in. Software-specific: Scope of the software we are expected to maintain is growing quickly, and there are natural growing pains associated with that, although they are being managed well.
