A first general interview to see if it could be a good fit. Nothing special here, just a quick 15-20 minutes chat with the Team Lead about past projects and aspirations (both salary-wise and work-related).
Second & Third technical coding interviews. Absolutely no info given prior to the interview, even when I asked by e-mail, I received no response (both times).
The technical interview number 1 was specific: on HankerRank, they had a program already written that I had to understand, find possible bugs and ways to improve, as well as code a new module. To me it was quite hard, but maybe because the coding language (C++) wasn't my preferred one, and they mentioned it was a new approach. We didn't manage to finish even half of the coding exercise in the 1hr interview.
The second one was more conceptual, they asked me how to approach a Computer Vision problem applied to a specific sport, and give actual processing techniques and mention state-of-the-art models to solve the presented challenges.
In the end they did not give me an offer, and did not give any explanation. I asked multiple times the HR person to tell me why they decided not to go through, but she never gave me any info, which I thought was not very considerate on their part.