It started out okay but ended with one of the worst interviewing experiences of my life. Process took over 3 months, 4+ rounds and numerous interviews. The questions were repetitive and multiple interviewers asked the same sorts of questions over and over again. It was clear that they didn't share notes with each other or have a clear interview strategy in place outside of having you talk to multiple people. They were highly unprofessional and sent the rejection email to me while I was doing an interview with one of their interviewers. I was having a back-to-back series of virtual interviews with different people at Two Sigma that day. I found out that I was rejected when I checked my email in the few free minutes that I had before I was to start the next interview with them, which I found out was canceled via the rejection email. After how much work i put in to prepare and do the multiple interviews with them, it was so disrespectful that they couldn't even told me directly via a call or at the start of that interview.