BEFORE ANYTHING ELSE: I suggest looking at their two rules and core values and REALLY pondering whether you feel like you could thrive in an environment like that before applying to Pluralsight. Everything about the interview process followed those principles.
The interview process is extensive and currently includes four steps.
1. A take-home TDD project (While it's true that the problem can be solved in a variety of ways, don't be afraid to make assumptions on how much you should test. Testing is technically an infinite space but they don't expect you to write an infinite number of tests. Just make your intents clear through the documentation of your code.)
2. A video interview that asks mainly about experience
3. A half-day interview where you solve a few technical problems and have a few non-technical interviews
4. A culture fit interview with the CTO and hiring manager
Wow! It's long, huh? But so worth it. As someone who interviewed with multiple companies at the same time, I can say without a doubt that Pluralsight's interview process was the best. Once we were in contact (After about a week) the recruiters were very prompt about contacting me, usually doing so within 1-3 days. This was VERY refreshing, as some places don't do that!
When I went for the half-day interview I was dreading the length of it, but once I stepped into the office I immediately felt like I was part of a large family. The interview was not a "prove yourself" interview like some are, where they expect you to understand intricate details of something specific, but rather a "let's work together" interview. When pair programming, we solved a problem together. The interviewer did not expect me to know everything, and he himself did not know everything. So we talked about the problem and figured out how to solve it together. It felt like teamwork, not a proving grounds. The day went by fast, and everyone made me feel comfortable there because they were so kind.
Overall it was a great experience, and while this kind of company might not be for everyone, it definitely is for me. Either way, the process was well-defined and took about a month from first contact. The recruiters were very professional and while they have a lot of work to do, they make it their first priority to guide potential candidates through the process.