I applied via email to the trainee program job post. 6 of us were invited at the same time, to an AC. It was a good experience. We has to solve situation tasks. They accepted several people to the program. We had a 1 month training (full day, unpaid, free). After that, we needed to pass an exam of what they taught. Everyone who passed was hired. (We needed to study, but they were fair in the exam.)