Shortly after applying online, I received an invitation to take their HackerRank test. This test had a time limit of 72 hours, so I made sure to have a relatively open weekend to dedicate to it.

Due to confidentiality, I cannot reveal the exact question, but it was a good exercise in data structures, matching, and optimization.

The requirements for the test, however, were pretty much terrible. In addition to grammatical errors (of which there were plenty), there were a few contradictory requirements. The test case output also remained hidden, making it a chore to infer which requirement was correct. Despite this, I managed to get 24 of 27 test cases to pass, and I figured that I would be disqualified at that point.

Surprisingly, I received an email requesting a pair programming/phone interview with one of their engineers. This went quite well, and I was asked to implement a lock-free queue after some discussion of my experiences. I performed well enough that within half an hour, I received a request for an HR phone screen.

This interview also went well, but it was more focused on them selling me on the company. I only had to answer a couple of questions, such as "Are you open to relocating?"

Following this, I had an on-site interview, which was also a good experience. The engineers with whom I interviewed asked some tough questions (make sure you're fully up to speed on data structures and optimization techniques), but I answered all of them, including explaining how my answer for finding local minima in a 2-D array was more efficient than that proposed by the interviewer.

Leaving the building, I thought I had done extremely well. However, I received an email later in the week informing me that they were pursuing other candidates. It would have been nice to receive more specific feedback, but overall, it was a good experience.

Insert a node into a binary search tree in a thread-safe manner without requiring locking.