Pros
Great benefits, generous stock grants, fun office, lots of company events. The company overall is an amazing place. It's a fantasy world that doesn't exist in many other places. The people there are generally great. Being in that office you feel like you are definitely doing something special with your life. If you get on the right team Atlassian will be the great company you will ever work for. There are a few areas within support that have a lot of happy people(but its rare).
Cons
If you get on the wrong team Atlassian will be the worst company you will ever work for. Everyone on the Jira team is unhappy but no one can leave. The stock compensation is so great that you will never find another role that pays better than your Atlassian salary + bonus + stock RSUs. This means unhappy people keep sticking around with their Golden Handcuffs getting tighter and tighter. After enough time you've lost more technical skills than you've gained so now are even more stuck. Obsession with metrics keeps everyone overworked and overstressed. Chasing arbitrary performance improvement goals leads to management working to block support engineers from participating in all the amazing company events. Your worth is measured by the time you sit in a chair at your desk rather than the results you deliver. Management uses Confluence to run projects because they can't be bothered to learn arguably the best project management tool out there, Jira. Even the Jira support team can't use Jira to manage projects because management can only use a wiki tool. Senior engineers on Jira support team are turned into supervisors to help whip the team harder and increase throughput, rather than focusing on technical work which would actually solve issues. Training was a joke, engineers are provided 4 hours to watch some YouTube videos or read some text and claimed to have "skilled up". Management has no understanding that technical training is something that has to be continuous and takes real time. Training of course requires long term investment, in the short term it requires engineers to not produce units of work with the understanding that it the time will pay off in the long run. This isn't valued because the metrics are looked at on a daily basis, all focus is on finishing the day/week with the highest numbers possible and dealing with tomorrow another day. The interview process is misleading. It's a very technical interview promising you will do a lot of technical work. Then you start and find out you are supervising people and documenting every conversation you have with junior engineers so that it can be weaponized by management. Your technical abilities will die here because all of your brainpower is devoted to playing the politics.