I passed a series of phone interviews with DE Shaw and they flew me to NY to interview on-site many years ago. It was for a statistician / machine learning role

I passed a series of phone interviews with DE Shaw and they flew me to NY to interview on-site many years ago. It was for a statistician / machine learning role. Once I arrived on site they asked me to write a program to rotate a matrix on the whiteboard. The catch was, it had to be in syntactically correct Tcl, a language I had never heard of, which was not on the job listing, not discussed in any of the phone interviews, and not on my resume. I clarified that I had never heard of that language and no one gave me any information that I had to prepare to answer questions about it and the two interviewers in the room said it was required for the job. I offered to code it in Python but they said it had to be Tcl. I was freaking out at this point, sweating, wondering if I was mixed up with a different candidate. I said the role I was interviewing for and asked if it was possibly a mistake, they replied it was not and they expected me to write Tcl for that solution. I thought maybe it was some kind of finance bluster sort of thing, like to test if I would stick up for myself or offer an outside the box idea. I sat down from the whiteboard and said if they could explain to me the syntax of Tcl I would give it a try. The interviewers both thanked me for my time and said the next interviewer would be in shortly (I had a printed sheet of a 9-5 full day of scheduled interviewers). I sat and waited in that room for over 45 minutes, no one came to get me, nothing. Eventually I walked back to the main reception desk area and explained what happened, and the attendant person looked me up on a computer and said all my interviews were done for the day, I was free to go, and they would be in touch. The point of contact was someone named Isaac Torres. I went back to the hotel they put me in which was right across the street, feeling incredibly depressed, and just ordered food and stayed in. My flight was the next evening, but around 11 am before I even left the hotel, Isaac called me to say they were going to pass on me. It was a weird thing. I wasn’t even mad because it was so absurd, like getting struck by lightning or something. It was like surrealism, irrational. But I sure did walk away feeling like DE Shaw the company is absolutely fucked internally, and I would never in a million years consider working for them and would try to warn anyone I can away.