First I had to write a C++ online test, it was reasonably difficult. It was followed by 2 technical rounds, one with an architect and one with technical manager. This was followed by one director round.
Good process of interview. Great learning. I got to know about this role through LinkedIn and applied through the same. I got a call back from the company requesting to attend the meeting.
The first round was a quick initial recruiter screening. We went over my resume/experiences, what I learned from past experiences, what I'm looking for in my next role, etc. Also had some behavioural questions, like tell me about a time you solved a problem.