I was given a take home assignment that was a very simple coding exercise to make a chat app. The guidelines were very simple and said should only take a couple of hours to implement. Completed the task to spec and submitted it. Got silence for a couple of weeks followed by an email to say they weren't going forward. No feedback given on the assignment (I know for a fact it worked to spec and was clean reasonable C++). So whatever criteria I failed to meet is a mystery to me. Felt very disrespectful of my time.