There was an initial phone interview with some basic tech questions.

The on-site interview was the interesting part. There was a fair bit of variety to the questions and the problems that were asked, which seemed like it would select for well-rounded candidates rather than specialists.

The on-site interview has four parts:

• An old-school pen and paper test with about 15 questions, of which only 12 needed to be answered (or be in the general ballpark of those numbers). The list of questions ranged from probability and high school geometry to Unix-specific commands, etc.
• An open-ended coding exercise where I was asked to implement a word count program in the MapReduce style. This is easier than it sounds, and no prior Hadoop knowledge is required.
• A couple of puzzles, which is not my favorite part.
• A system architecture is described to the candidate on a whiteboard. The candidate can ask questions, etc., and after a few minutes of this, the whiteboard is erased, and the candidate has to explain it back to the interviewers on the whiteboard.

Given 25 horses, how can you find the top 3 with the minimal number of races? Don't worry about the ordering within those 3.