The interview process consisted on an initial phone call with the recruiter, followed by a takeaway technical exercise and finished with another technical interview on the phone. All in different days, of course.

I applied September 17th, assumed they weren't interested when there was no response within a couple of weeks. On Oct 27th I was emailed and given a coding assignment involving designing a job queue to process an event stream in real time. Next on Nov 6 I got an intro call with someone from HR. On Nov 9th I had a technical interview via hangouts and etherpad which took about an hour--the questions were more "how would you approach this problem" than "code a solution right now". On Nov 30th I had 2 more interviews with data science team members via hangouts; these were "see if we like you and you seem like a good fit for the team" interviews. Finally on Dec 10th I had a hangouts interview with the team lead. I received a rejection email on Jan 4th; almost four months for the whole interview process! HR called two days later to follow up. They told me they had marked my resume for future talent searches; it was definitely the nicest rejection I've ever received. I got the sense they have some organizational problems, which seems pretty standard for non-profits.