Pros
The environment of a startup was nice, several opportunities to solve complex problems, since a big part of the company employees were there just to get a paycheck, because they were friends of the owners. There was a few developers that were very good, specially the ones working with the live application and devops team, I was able to learn a lot with them.
Cons
Lack of management and focus on build a better product, specially in the tech team. I felt that completing tasks was less important than being a nice person on slack and in the company events. It's not cool to work in a place where you fell that you are doing hard work with your team, but at the same time you see many other employees basically doing nothing, or at least not showing what they were doing. I didn't like the culture of saying bad things about other companies either, neither that founders were making meaning jokes about ex-employees in slack either. I heard stories that they chased ex-employees after they left. They did a quarter event with everyone, but it always felt it was not to build a team, instead it felt more like a moment for the 3 owners to show their big ego, specially the CEO. There was a day that he even used a dollar gun to finalize his speech, no comments.