There were in total of 3 interviews. First one was basic HR interview with hiring manager to see if you are a good fit for the company. Second one was a phone interview with a coding question. This question was pretty simple, so anyone minimally qualified can solve it quite quickly. A week or so later, you will get an email that you are invited for an office interview.
The in-office interview was much more complicated coding problems. I signed NDA so I won't reveal the questions, but I must say the result of these coding questions were highly contingent on whether or not if you have seen the problems before or not. They are almost like brainteasers. So even if you have sound CS fundamentals, if you don't know trivial tricks for the problem, you will not be able to solve them.
Their office is pretty cool. Seemed a bit crammed, but it definitely seemed like a company that's growing. Everyone seemed hard working and driven.