Pros
Ancestry offers competitive salaries and generous bonuses, and they are very family-friendly and flexible. Ancestry is in a period of growth and improvement, so there are lots of opportunities to acquire new skills and exposure to new technologies. Upper management is very concerned with staying ahead of the curve in efficiency and technology. We're in the middle of an exciting "tech transition," moving from .NET and proprietary technologies to open-source ones like Node.js, Python, and others.
Cons
Because Ancestry is in something of a transitional period, things can get a bit bumpy. That is, while there are many new projects and initiatives, often times the infrastructure or other support for them is not yet there for you, or it's in the process of being developed while you are working on your end. This can get a little frustrating, though I suppose it's par for the course in a transitional period. Also because of of this transitional period, teams can get laden with what seems like a rapid or near-simultaneous succession of high-priority objectives, which can sometimes make it challenging for teams to be productive (or to feel like they're being productive). The IT department is rather under-developed and could use some help in their processes.