Received interview through reference, 2 back-to-back 30-minute interview sessions. Rude, unprepared, ready to insult ("I think you were a little too rushed in preparing, you can't really explain the concepts very well"). Can't imagine that it would be pleasant working for these people. Cut me off as I was talking or trying to respond to questions. No direction from HR, interviewer didn't even seem to know that I was supposed to be in that slot for that day.