First round was a conversation with HR, which was fine. Then a technical assignment /homework, which was a regular Rest Api with some trick/extra challenges. They accepted it and got called into a technical discussion with 2 seniors. It was a nice experience, they asked technical questions and also asked for some explanation of my code, solutions, ideas. I have explained that due to the time limitation (which has been stated in the assignment description) I chose this and this shortcut and shared some other improvement points and future ideas. After this more than 1 hour call I got a rejection email which contained feedback of my assignment. Their reasoning were exactly 2 of the shortcuts/choices we discussed in the technical interview (and I explained it thoroughly) and naming. Nothing else, like the techical discussion did not happen or did not matter. Overall I had nice conversations with HR and the devs, they were pretty quick with the responses/interviews but the reasoning ruined my whole opinion, it was so outrageously ignorant.

Four interviews, a meet, then a technical - this is probably the hardest, then a team fit interview, this is where they see if you're the right fit for the team, and finally an interview with the CTO. Overall very friendly and polite.