This hiring was for Pune location and interview happened in Bangalore. I was contacted through a consulting agency, and when I went to the interview location at the scheduled time, I was told that it was first come first served. I had to wait for 2 hours and then in the interview, the interviewer was not even listening. He was more worried about not having lunch at 2 PM. And his behavior was so rude as if he just wanted to get rid of the process. Questions asked: Tell me about executor framework. Difference in Future and Callable. Singleton and Decorator pattern. How do two systems communicate with each other? I answered all of them but considering his behavior I left the venue after the first round. Will never ever apply for Citi Bank in my life.