Too Long; Didn't Read
An in-memory database is a great way to understand an interviewee’s approach to coding. This type of question can replicate the work environment very closely: you are under time pressure and there are too many options of what you can be done; you need to make choices fast and produce working code while also making it possible to extend and improve it later. The first question is to ask questions to clarify expectations and reduce the amount of work. If you are new to this question, you may wonder what kind of question it is.