The interview process was divided in 3 different steps taking more than 4h and, when delivering the solution working, they only give you a negative feedback with a pre-defined answer. The HR interviewer was a very nice person, but the feedback was horrible.

It depends on what are you applying for but not the level (at least when I made it). You basically just have to record yourself seeing and talking through the whole solution. I had to create a backend in Express to send mock data, read and map each of the nodes sent by the BE.