I've been contacted by a recruiter for a first phone interview. After it they sent me a HackerRank link to take a 45 minutes online test. Since I passed the test I've been contacted to schedule another phone interview with a couple of their software engineers, but in the meantime I received a good job offer so I didn't go on with the process. I have to say that they're really nice and proud of what they're doing as a company.