I had two Skype interviews that lasted 45 minutes each, one by one.

During the first, I was asked standard questions on algorithms. I also had a task to implement one of them. Then there was a talk about my CV.

The second interview asked a very high-quality system design question. We iterated and improved the solution for 30 minutes. I had to implement the basic version. Then we talked about some edge cases on extreme large datasets.

I was asked to implement an algorithm.

It is a pretty easy question for small datasets. However, when that question was expanded for large datasets, it became very interesting.