I was approached by their in-house recruiter via LinkedIn. I was sent an hour-long online test, that consisted of short algorithmic tasks. The level of the tasks varied: some were laughably easy to solve, others were way too hard for a simple online screening. Overall, it was a mixed experience.
After about a week, I was contacted by another recruiter via phone, who asked me to come in the office for a quick chat. He introduced me to the company and what they could offer. We also had a rather lengthy discussion about my goals, career-wise, and how the company could help me to achieve these. At the end of the interview, I was given a simple coding task, once again, which I had solve on paper, in about 15 minutes. I was told the solution would be given to a tech guy, who would evaluate it later.
After a couple days, I was invited back to the office for an official technical interview. The interviewer mostly asked me about my past experience and the skills that I listed on my CV. Besides this, I was given two really simple exercises (think something like fizzbuzz), which I could solve in a couple of minutes. After the interview was over, we chatted about software development in general for quite a while. The interviewer was very professional but also laid back, and there was no pressure at all.
After another week, I was called into the office once more, to formally close off our negotiations. This final round mostly consisted of negotiating about the financial aspects of the job, and also if I'm a good culture fit.