I've had multiple interviews at Scality
First a phone interview with the recruiter so they get to know you and give you a little taste of the job and the stack you're gonna be working with.
Short Python coding test sent by email, to do in 20 minutes. To see if you know the basics of Python.
Then an interview at their place with the manager. He explained everything about the job and made sure I was liking everything about it. Tested a little bit my way of thinking and prepared me for the rest of the process, explaining all the steps I was about to face.
A two hour test to do via a specified website called Codility. This test is designed to see your algorithms skills. I failed this step, and they were a little bit disappointed but they decided to continue the process.
Then I went again for two interviews of one hour each. One interview with one of the team's developer, to test my algorithm skills, how I think, and some Python knowledge. And the other one with the Tech Lead, less technical, but more about how I work, how I think. I failed the technical interview again. There was a lot of basic knowledge like Big O that I didn't learn at my university so I couldn't think and answer all the questions, as they wanted me to.
At the end they decided to say no to me, and asked me to study and comeback a few months later. They told me to take a look into the book called Cracking the coding interview (which by the way is excellent I highly recommend it for any Tech person who's looking for a new job). And that's exactly what I did.
Two months after, I applied again and went through the process, after managing to do the technical tests:
An interview with the VP of engineering and an interview with the COO.
After this I got the offer.
Overall the process was very long, and even more because I've failed during it (So I ended up repeating a step in the process). But I felt accompanied during the entire process, the recruiter is available at any time to keep you well informed. Extra care is taken.