I had three rounds of interviews and generally it was a pleasant and comfortable experience. The recruiters I dealt with were friendly and relatively responsive, and the rest of the interviewers came off as people who would be nice to work with.
Where things went south was with the end of my interviewing journey. I had my last round of three interviews on a Friday. It wasn't until late in the day on the following Thursday that I noticed I had a missed call from the recruiter (thanks, iOS spam call filtering...). The message mentioned that there was an update to share with me, but the recruiter was going to be out the follow day, which was a Friday, so if we weren't able to speak before the end of the day on Thursday, we would talk the following week. I called back immediately, but I was only able to leave a voicemail. This meant I was in for an agonizing wait of at least three days to find out what the update was. (Although, due to the lack of urgency on the FanDuel side, I wasn't optimistic.) So I suffered through a three day weekend of anxiety, only to have my doubts about moving forward confirmed on Monday. It was a huge bummer, but it happens. The recruiter agreed to get some feedback from the team on why they didn't want to move forward, which seems like the least that FanDuel could offer in compensation for the significant amount of time (including my last sick day for the year) and emotional energy I'd invested to make it this deep into the interview process.
Aside from the potential feedback, I assumed I was done with FanDuel, and ready to move on. But the following day I had another missed call from the recruiter, and another voicemail. In the voicemail I was greeted by name and told that a written offer was being prepared and I was asked if I could attend a meetup among FanDuel tech folks the following day. Again, this call came towards the end of the day, but in my utter confusion, I followed up with no response that evening, I spent another anxious night wondering what in the world was going on. The following morning I received a text from the recruiter apologizing for the fact that they had called the wrong number. It's still a mystery as to why the voicemail greeting addressed me by my name, which is a relatively uncommon name.
And I'm still waiting for feedback from the team.