There were two 1-on-1 interviews where the interviewer, your potential future co-worker, would probe your algorithm-solving and system design skills.

Then, an engineering manager would probe your skills deeper with real coding for architecture design.

The HR representative provided updates on all the 1-on-1 interviews, for example, in three days.

In the end, they put me in the offer process and asked me to submit five references.

After two weeks, I received the rejection based on the reference check report, which reflected low potential.

I reached out to all my references, and they were surprised by the result, as they had given me mostly high ratings.

I tried to get more details, but the HR representative couldn't help due to an NDA.

HashMap vs. ConcurrentHashMap

Given a requirement that you have to implement a video player view, where you have the server API, what would you design the architecture?