Interview process started with a 45min call with a recruiter, she was very nice and explained the full process to me which would include a phone call, a video interview and then an in person interview. The phone call was fine, just talking about general background and the position. The video interview was a case study about returns with a basic math problem, the interviewer was very nice. Next I moved onto the in-person interview, a little over four hours. I met with potential coworkers and a few people who I would never work with that were just stand-ins. I thought overall everything went well, this is where my experience turned completely. I have at this point invested over 7 hours of my time applying for this job, I never got a single email or response from wayfair ever again. I tried reaching out once a week for a few weeks and never got a single reply...very odd, very unprofessional.
Overall: Be prepared for a long interview process with the same questions about your background and A/B testing questions they have been using for years and you can find on glassdoor. In the end you might not even get an explanation or a simple email back saying you were selected or not.