I first applied to Atlassian through their online careers website. Not long afterward, I received an email with a link to an online set of challenges. After solving them, they might consider offering a phone interview.

The online questions were not difficult and were not timed. They consisted of four multiple-choice questions about intricate Java details, three somewhat long coding questions that were not too complex (e.g., flattening a tree, implementing a recursive algorithm iteratively without knowing its purpose), and a couple of short discussion questions about my motivation to work there.

After passing this stage, I moved on to a phone interview. This included standard questions (e.g., "Why do you want to work at Atlassian?"), behavioral questions (e.g., "Mention times you worked well in a team"), and some very easy technical questions (e.g., "Difference between a set, a list, and a map").

Finally, I was scheduled for the final round interviews. These are normally conducted on-site in Sydney, but as I lived in Melbourne, they were done over Skype.

There were three interviews conducted consecutively:

1. A "technical" interview: This consisted of theoretical and practical questions about Java, algorithms, concurrency, and other topics to gauge computer science proficiency.
2. A "whiteboard" interview: I was asked to walk the interviewers through a significant past project, detailing the design process, the reasoning behind specific decisions, and so on. Warning: You are expected to lead this interview and showcase your project. My mistake was being too passive, waiting for questions instead of proactively explaining, which led to them not fully understanding the project.
3. A "coding" interview: This involved pair-programming where an interviewer watched my screen and offered ideas. I had to implement a Stack in Java that passed given correctness and performance unit tests. The problem was quite easy (completed in under 10 minutes), and the requested extensions were also straightforward. Warning: You are expected to communicate your decisions and tradeoffs very clearly here. My mistake was not convincing the interviewer that I understood the concepts, as I expected prompts for explanations when I made certain choices (like using an array), while they expected me to proactively demonstrate my understanding.

Overall, the process was clear and timely. However, I felt somewhat unfairly treated by the final interviews. Conducting them over Skype and not fully explaining my responsibilities in each interview made communication more challenging.

I would advise anyone undertaking these interviews to be ready to convince the interviewers of their understanding of the problems and that they have thoroughly considered options before making decisions.

Take us through a project you've previously completed, and all the challenges, decisions, and research involved with it.