All I have to say is not WASTE your time on the Canonical interview. 24 hours after applying, I received an email stating I passed the resume screening round, and the hiring manager asked me to do a screening task with 30 questions about my experience, and my high school and university life. At that moment, I valued the interview, and I wrote at least 400 words for each question and spent two weeks (Christmas break) on this. After the new year, I received a psychological test and wasted one day preparing it, I answered all the questions in a fast and accurate way. One day later, I got a rejection email from the hiring manager, who said he would not progress my application. Instead of giving me a proper reason for rejection, the hiring manager stated that Canonical is a great company and everyone wants to work here, and that's why Canonical received 80,000 applications each year(to be honest, I don't understand what the logic behind this, showing off? maybe). So I wrote an email to follow up on the reason and never heard again from him.