The interview process consisted from two stages.
The first stage was a call with two people and there was a quiz on different topics about SW development, Machine learning and Math.
I though I did quite well.
The 2nd stage was the call with CTO, where he basically started to repeat questions from the first interview. Sometimes going into more details. Overall quiz was kinda easy for me, although of course there were things I didn't know but I still got rejected without reason why.