Was called for a first technical/culture fit interview, was introduced to the role and then asked to talk about my previous experience. The interview went pretty well and I was promised next steps within 2 business days. Then I was ghosted, no response even after I followed up 5 business days after the interview, and then once more 10 business days after the interview.

While the HR personnel were courteous, the process was slow, with one to two weeks passing between each round. I regard it to be a red flag to that the interviewers would hand out multi-day take-home assignments at only the 3rd round out of a supposed total of 5(!) rounds, apparently to stall for time when they are finalising the process with another candidate. The requirements were relatively simple and straightforward, and prototyping the code took half a day. However, the interviewers put great emphasis that every step be meticulously tested, formatted, justified and explained, and that took a further two days. In the end, they apparently did not spend more than 20 minutes on my submission which took over 2 days. They claimed they had trouble loading the data, whereas I explained clearly how to do so in my opening paragraphs. Furthermore, I had tested that the data loader would work as expected on a third computer. 1st round was a medium/easy Hackerrank question. 2nd round was an hour long conversation with engineers from 2 different departments. 3rd round was a take-home project, and candidates were given one week to implement it. The 4th and 5th round would be more technical and cultural fit conversations with the engineering team.