I applied online. The process took 2 weeks.

I ended up applying to this position because I saw here on Glassdoor that they have an interesting recruitment process with lots of brain teasers. I applied through their website. I've written a short motivational letter, and in a couple of days I got a message accompanied with a link where I could find the famous problems. There were 7 of them, divided into 4-6 questions (most of them with multiple choices, some with single choice), with a maximum allowed time per problem of 30 minutes. So there goes somewhere around 3 hours of my life completing the problems, scratching my head, and coming up with solutions. For some of the problems you need some basic math skills, for others some basic logic skills, and for others you just have to pay attention. I wouldn't rate them as difficult, but neither can I say that I know if my answers were correct or not. Some of them I found quite repetitive, and they stressed the same qualities of the person that was interviewed, but there's that.

After a couple of days I received a congratulations message accompanied with two more problems this time. Both of them had to do with me implementing an algorithm that would process some numbers or series of numbers. The response had to be submitted in no more than one hour and a half in any programming language or pseudocode, along with a short description of what, how, and why it does what it does. The first one I would say I did perfectly—I think there is no better solution in terms of time and space complexity, and it was well documented as well. The second one, on the other hand, I messed up—I provided a partial solution with some bits missing and an explanation that was supposed to fill in for the missing parts. Add this 3 hours to the 3 hours before, and in total I spent about 6 hours for this first step of the interview and screening process. Almost a week later I got an email that I was rejected, and they will make a 10 euro donation in my name for thanking me that I invested this much amount of time in this process.

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