Consisted of an initial screening call, then a machine learning related technical exercise to do in your own time, then a presentation about the exercise at an hour long final interview. It's not particularly hard if you have a background in ML/data science, but it is a more time consuming and arduous application process than most companies.
The reason for my negative rating is that the job description did not match up with what was described at the final interview stage. There was no mention of the role being a manager/senior position involving leadership of junior team members, yet this was stated during the last 5 minutes of the final interview, once I had already passed the previous application steps. This is a level of seniority my experience did not align with and that I would not have applied for in the first place had I known, so the whole thing was a waste of time. Clearly there needs to be an improvement in the advertised job description and the screening of candidates to avoid situations like these.