Pros
I was able to work with some great folks (some of whom I'd worked with at other companies) and the technology is cutting edge.
Cons
The first red flag was that they laid people off just two weeks after I started there. That should have told me to start looking for a new job, but I convinced myself that that was how things worked at a startup. Well, I had to tell myself that three more times until it finally happened to me. I worked there for a total of eight months before I WAS LAID OFF BY E-MAIL. Five layoffs in eight months. The last was ~25% of the remaining workforce. And, each time there was a layoff we got the same story from our CEO - this will give us runway for the next 36 months and this is all on me. Some one, please, explain to me how a person who admits five times to the entire company that he screwed up is still employed and still the CEO?? Anyway, you live and you learn. If I do go to another startup, I'll make sure to do a bit more research and make certain that the CEO isn't some inexperienced millenial with lofty ideals and no clue how to implement them.