Great coworker here, everybody is doing their best to make the company better. Meals and unlimited snacks are provided (love that)! Plenty of Opportunities to dump on different projects that you are interested in, a lot of challenging job that is worth to try. Typical start-up life, challenging, constantly changing and growing, busy but fun.
Cons
A lot of work to do due to the fact that it's a start-up, but that's everywhere, and all the work has a outcome, which is rewarding.