The process is very unstructured. It seems like they don't even prepare/know what they want to find out beforehand. There are a lot of awkward pauses of 1-2 minutes where they just stop and don't ask you anything.
I very much regret ignoring the reviews posted here, Because after the first part of awkward pauses for 45 minutes, they give you a test assignment that would take at least a week of full-time work. They expect you to complete it in a week, not taking into account the fact that people are doing their regular jobs in the meantime.
Worst of all, they give you very short feedback on the test assignment, which clearly shows that they haven't even looked at the code you spent a week on properly. I wouldn't recommend applying and wasting your time.