Pros
When Atlassian is good, it's great. Your peers are smart and motivated People generally trust one-another The experience team really does a great job of perks (lunch, special events, etc) If you're performing well: There's a lot of space to grow your career (either vertically into more senior roles or horizontally into other fields) You can switch teams (allowing you to maneuver around the Cons below) Atlassian has a great brand, it probably looks great on your CV
Cons
When Atlassian goes bad, it goes really bad. There's a lot of project churn (projects appearing and then disappearing) Managers at Atlassian aren't great. Every manager I've had has been a former developer who moved into a team lead role. Nominally speaking, you'd think this sounds great. However getting the most out of people isn't something that a career in writing software prepares you for from what I can see. When they leave you alone, they're mostly benign, although you'll have to find your own career path. If you have sustained high work output, and you know when to keep your mouth shut, you'll be in this category most of the time. If you happen to get their attention for the wrong reasons however, you're in for a world of pain. Their abilities at "performance improvement" are mostly limited to threatening to fire you. FYI take the values with a grain of salt, they used to mean a lot to a lot of people (management and staff) but their meaning has become diluted as people have been hired who don't share the same values.