I was just wondering if GitHub Classroom could be used as an interview step. I've not looked at Classroom very closely but I have a couple of questions; how do you handle the interviewees? Do they have to create their own user or do you re-use some generic ones?

If it works like I expect it to, you should be able to create different "classes" for different roles; SysAdmin, Programmer, Designer, etc. And you could create increasingly more difficult tests; build a web page, personalize it, add a cart, etc.

How are you guys using Classroom?

Does it allow you to set a hard time limit on how long the candidate has to complete the challenge?

Yes you can set deadlines for assignments.

Its interesting to see you use Classrooms for the interview process :)