First I had an info meeting where I got to hear a little bit about the company.
Then we arranged an interview that consisted of two parts: software engineering test and research capabilities test. The software test was mostly composed of C-related questions, with emphasis on understanding the data types, memory usage, pointers, and common patterns encountered in C programming. The other part of the interview tests your capabilities to understand scientific articles. For this, you get a scientific article to read before the interview. Questions were focused on the key concept presented in the article. You can expect questions about previous state-of-the art, advantages and limitations of the proposed method, implementation details, evaluation metrics, and similar. Both parts of the interview were quite relaxed since you get some help in case you get stuck in some questions.
The third part of the interview was meeting the team in person and talking about previous experiences and future plans. This was also very relaxing and cool as you get to learn more about your possible future colleagues and company culture.