I applied online. I interviewed at Canonical (Zagreb) in Oct 2022
Interview
The canonical interview process is notorious for being slow, inefficient, and incredibly demanding. You can find a lot written about it on the internet and if you search youtube, twitter, hackernews, glassdoor - you will find a lot of negative things said about it and also comments from the CEO Mike Shuttleworth rigorously defending it. Having recently interviewed at other companies too, I can definitely attest that a lot of this negative feedback is true. The process is really unusual. However, it would be unfair of me to say that the interviews and research I’ve done around Canonical’s products hasn’t helped me with my career (e.g. Alex Jones from Canonical has a really nice youtube channel that thought me some cool stuff). The interview started off with a “Written interview” - you can find many examples online and it’s a pretty big list of relevant and irrelevant questions. This step can take a really long time if you want to answer all the questions with quality. After going through the written questions I was given a Thomas International IQ test. They won’t share the results with you automatically. To get the actual results after completing the IQ test you have to send multiple emails to HR recruiters which will first send you a dumbed down version of the test results (they say they share the dumbed down results to preventing you from falling into depression). To get the full results I had to send 5 emails in total. The third step was a generic HR step. They said the point of this step was for you to see that there are real humans behind the automated emails. This step is quite pointless but you get to talk to someone from Canonical. The fourth step was a take-home assignment. I was tasked to create a “production grade” python program. The program is supposed to read some debian repository information - you can use google to find implementations of similar programs. The fifth steps were two technical interviews. The guys in these interviews were nice. After both interviews I asked about the Canonical's products and the fact that they are not that popular - I noticed that reddit polls don’t even mention their products as a poll option. The interviewers admitted that the products are not gaining traction. The next day I got an automated rejection email. I’ve asked for interview feedback but I was given a generic response. - I’ve heard most companies don’t give feedback to candidates these days so I guess that’s fine. The overall process was extremely long and exhausting - I think I like the FAANG (tech-screen + on-site) format a lot better because it is more respectful of your time. I would recommend you apply only if you really like the role or one of the products.
Interview questions [2]
Question 1
write a simple python program that uses a bunch of functions that you can assume are implemented. These functions that connect to a server, retrieve some keys, and can check the keys for validity. The point of the exercise is to see how you would write code that does proper error handling and check validity of values (it’s relatively simple). Next you discuss how you would scale this code (some results can be cached while some can not).
parse a binary file with python (the interviewer gives you a handy stackoverflow link - but not immediately). You have to search the file for some data. This is a bit more tricky because the python api for parsing binary files was a bit confusing to me - but the end program is not that complex to write. And then again you have a conversation about optimising the solution in case the file is much larger.
I applied through a staffing agency. I interviewed at Canonical in Jan 2026
Interview
I understand they are looking for a very specific type of profile. It's just not for me and after a long form with 30+ questions, some of then about my teenage years hobbies or my grades in school, and a intelligence tests consisting on sesame street knowledge like "Peter is taller than Jenny. Who is shorter?" i just withdraw, if that is the respect they have for candidate time i am not a good fit for their culture.
Long process, took a lot of time to complete so-called "written interview", talking about your academic performance during high school and college, which is hated by most people.
Interviewers are kind, however, it sucks when the interview process takes you 40+ days to get a rejection email.
Interview questions [1]
Question 1
Find the position of matched bytes in a large data memory
It was lengthy. There is the well-known written interview, followed by a basic programming test. Lots and lots of Google Meet interviews. Many of the interviewers asked the same questions. A panel interview would have been a lot better.
