Overall process took me two and a half month.
After a week from my application they sent me a general math test link. After a week or so, I got an online meeting invitation with the HR. First meeting with HR was generally based on my prior experience and some related questions about it. I've also been given general information about the job and the conditions, side benefits etc.
After the zoom meeting I've been invited to the office to meet with department head and manager. We had approximately 45 minute interview which was mostly about how I can contribute the firm etc. After a week we scheduled another meeting at the office since the manager couldn't participate the previous interview. I've also been told that I am one of the candidates they're intending to hire. After two weeks of no contact they just sent me an auto-HR message saying they're rejecting me which I'm totally fine with it. However, in my opinion, rejecting a final-stager candidate by an automated HR mail, definitely an unprofessional attitude that creates a negative image of the company.