Pros
Really, really smart people who are talented at what they do, and get a lot done. They place constant attention on what their culture is and what it means. This has brought certain perks like paid leave set aside for volunteering, embraced transparency about company goals and policies, and camaraderie with teammates. At Atlassian, you are truly empowered to work on the stuff you want to, even if it's outside your prescribed domain of expertise, and collaboration across cross-functional roles is something you can count on. The kind of things teams are building and doing are truly interesting, and there's room to contribute. I've worked with some of the most talented people in my career here, across many different departments and products.
Cons
Many people are working insane hours under the radar, including many managers. Many aren't. Internally, it seems well-known that most people are underpaid well below market value, but even with options, it's hard to justify. Sometimes the attention to culture feels like navel gazing; and some of the cultural values aren't authentically lived (as any company). Product strategy is aging in an interesting market, but the company hasn't yet learned how to guide decisions with meaningful market input. Diversity is sorely lacking, and they aren't yet addressing it and many meetings are filled with mostly young white men.