Three part process - preliminary screening, a casual tech interview, finally an interview with the development manager and a group lead or someone of that caliber.
Tech part was nothing special, although the HR employee was super bored and not even supervised the interview. The tech guys were clearly uncomfortable interviewing someone. Talked a bit with engineers after, asked to show me around some, where they did open up a bit.
Interview with the development manager and some other guy i don't remember, was kinda casual talk, motivations, how they work etc.
Bear in mind this was some time ago the current year being 2020. This was 1.5 years ago, the staff probably changed since then.