I applied online. The process took 2 weeks. I interviewed at Monzo Bank (London, England) in Sep 2019
Interview
- phone interview with a backend engineer
- tech task (web crawler in Go)
- "code review"
I put the code review stage in quotes because it really wasn't. At no point did they ask me about my code except to challenge my use of recursion. I acknowledged that recursion is suboptimal but that I had set it up in a way that it limited the number of http connections and had done time tests. It also was the last bit of logic I implemented and because the whole thing was fully tested, end to end, that bit of logic could easily be swapped out. I fully expected this to be a topic of conversation and even mentioned it in my README. Unfortunately, the interviewer didn't seem pleased with the fact that I had acknowledged the area for improvement and continued to ask deeper and lower level technical questions completely unrelated to my code. It really felt like he was trying to prove I was an idiot and the whole interview felt demeaning. Admittedly I was completely thrown off and started to get really turned around. The questions, even after having asked colleagues how they would respond, seemed extremely vague and like he was expecting a specific response. At one point the interviewer asked why you would limit the number of processes on a machine (a topic I had off-handedly mentioned due to the introduction of the connection limit that I put in) and I said due to the limitation on resources in a machine that you would not want to hit. This didn't seem to satisfy him and after what felt like forever, I flat out told him it sounded like he was looking for a specific answer and asked him what he was looking for and he simply said "memory".
The interview had a tinge of hostility throughout and by halfway through I was pretty convinced that even if they offered me the job that I was not interested in ever working in an environment that seemed to support this type of d* measuring contests. I'm a woman and it felt like a huge red flag to me.
I also asked about testing and the interviewer said he's on a team that is too important to have time to test! I also asked about the fact that Monzo doesn't CI/CD and he said it's not needed.
I sincerely hope that Monzo's interview process doesn't represent the culture and that this interviewer is just an outlier.
I was told in my feedback that I had really solid code but that I lacked really basic CS knowledge and would require too much mentorship. How did my poor female brain produce such solid code without someone to hold my hand I'll never figure out!
1. Recruiter call — short intro, they explain the role, you ask questions. Low stakes.
2. Initial call (1 hour) — this is the one to prepare hardest for. They've read your CV and want to go deep on a recent project: how it was built, what trade-offs you made, what you'd do differently. It's a conversation, not a quiz — but they will probe the technical details. Pick one project you can talk about inside out.
3. Coding exercise — your choice of take-home or live pair session. Take-home is async in your own IDE, any language, includes a README where you explain your decisions. Live pairing is 45 mins with a Monzo engineer, implementing functions against a provided interface — not leetcode, no binary trees, just practical work. Both end in a review call walking through your code.
4. Systems design (1 hour) — design a scalable system for a hypothetical problem using Excalidraw. They care about your reasoning, not your diagram. Don't namedrop buzzword tech unless you can defend why — they will push back. Know your CAP trade-offs and be able to explain your choices from first principles.
5. Behavioural (1 hour, two interviewers) — communication, how you deliver complex projects, how you work with a team. Be specific about what you did personally versus what the team did. STAR format, concrete examples.
I have never had a more unprofessional interview in my career.
The interviewer had his camera on and was clearly working in his bedroom(which isn't an issue) but he didn't blur the background and he had laundry, including his underpants, hanging right behind him.
There was also an open door in the background that someone kept walking past which was distracting.
He was jumping all over the place with questions during the interview and kept interrupting to take notes which threw me off.
It's a shame Monzo don't have a better structure to their interviews.
I applied online. I interviewed at Monzo Bank (London, England) in Mar 2026
Interview
Same interview process as mentioned on the Demystifying the Backend Engineering Interview Process blog page on their website. I, however, got rejected in the take-home review round. All of the interviewers involved were really nice and warm, and they seemed to have a good internal company culture.
The take-home code review round was good in some areas but seemed vague in others, such as scaling. The interviewer was asking questions while trying not to hint at the answers, and in that process the questions turned out to be super vague with some getting lost in translation. The interviewer constantly referred to "semaphores" as workers, which is conceptually incorrect. I also want to add that referring to semaphores as "workers" confused me as to whether the discussion was about scaling in a distributed production setup or something specific to my test code. This missing distinction disrupted my thought process and I got lost thinking about what they were expecting rather than taking an analytical approach to the answer.
It looks like they expect specific answers to some of those questions. This pattern is evident if you look at others' interview experiences here.
Interview questions [1]
Question 1
Crawler take home test, scaling, retry mechanisms, advantages and disadvantages of each choice of data structure, etc