Mashgin Full Stack Engineer interview questions

The process consisted of 3 rounds that run for around 3 weeks. The fist one was a quick interview with another Software Engineer from Mashgin to discuss past experiences and roles, the second was a take home assignment to create a small system with back and front end, and the last round was four interviews in a row with different roles from Mashgin. Although tiring, the last round of interviews were not very repetitive, but the last interview with the CTO was very confusing. It was supposed to be an Architectural Interview, but the problem given was very generic and without any details (giving the impression he was either uninterested/unprepared for the interview or didn't really know what he was looking for). In the end, the answer was negative, but no justification or feedback was given.