Very unprofessional and impolite ways, first round is phone screening, then 3 individual ones half hour each, for the last one the interviewer did not even show up, so I waited and someone came to apologize after 15min waiting. Some interviewer came into chat without any introduction and left without notification, they don't like smiling and don't greet people or be a nice way to start the chat.

there are several short sections with different experienced levels people will interview you for 30 mins. they are very nice and questions of interview are not hard but very comprehensive