After a very quick interview (call) with the HR they sent me an email asking for a coding challenge. They always attach a pdf with the explanation of what you have to accomplish in each interview step. For this step the requirements were pretty clear : "We look to understand what you think is important when coding, and how your skills and problem solving approaches match up with the requirements of the level you have applied for." What Do We NOT Expect? We are trying to understand how you solve problems aligned with our values. We do not require you to show the breadth of your knowledge in your code. You get to do that in the next steps. Time Frame (Deadline) We ask you to complete the case over a 48-hour period and by a certain date which you will agree with your recruiter. Usually it takes an investment of around 5 - 6 hours on this exercise. The coding challenge was hosted by HackerRank, considering that the time window was 48 hours I decided to "invest" my weekend to complete the test. The coding challenge was quite "standard" but at the same time they asked for very strict requirements like : "all the APIs must have a O(1) complexity" From the beginning I figured out that 5-6 hours was not enough, but I decided to spend more time on it. I was really interested in N26, the role, etc... I spent in total around 12 hours and I was really satisfied when I submitted the answer! All the tests were OK. After less than 1 week I received an answer : GREAT! The answer was : " PROS - The basics requirements are met - The tests are present, solution is thread-safe and O(1) solution CONS ..... In general the code is not quite where we would expect for a Tech Lead, since they are responsible for looking after standards within their team. The code is hard to follow and it seems to have leftovers from other code that was copied and pasted. Overall, we have a few questions and a few things to figure out - so we'd like to invite you to an hour long technical interview with two of our Engineers. When would you be available to do this? " So I gave my 2,3 time slots to proceed with the process but I decided to send them a feedback from my side : " I'm sure we can go deep in any aspect during the next interview. "5-6 hours" exercise it's a very optimistic estimation especially distributed in 48 hours. I spent more than 12 hours and I agree with you it could be better, faster, stronger but I had no more time to dedicate to it. I will be available on : ..... " Probably because they didn't like my feedback I never received any answer from them. I spent 12 hours to complete the test, never had a face 2 face interview, they accused me to copy and paste the code ( :| ) and I never received a positive or negative answer. Their recruitment process is broken : wrong estimation, very rude answer when they answered and "silence" when I just shared a feedback with them.... Very bad experience, very bad candidate's experience, ...