The coding is to get a sense of how they write code, how rusty they are, how many good habits they've picked up relative to their experience, how do they think

The coding is to get a sense of how they write code, how rusty they are, how many good habits they've picked up relative to their experience, how do they think about validation/testing of it, how the go about building it (ad-hoc vs top down), their problem solving skills when faced with an unknown problem and so on. There will always be unknown unknowns. We are just trying to cover the known variations and if he has any unknown knowns[1]. 1 -https://academic.oup.com/jxb/article/60/3/712/453685 https://academic.oup.com/jxb/article/60/3/712/453685