I like to ask the candidate to do a code review on a pull request. It needs to be something where they'll be able to demonstrate a good grasp of the fundamental

I like to ask the candidate to do a code review on a pull request. It needs to be something where they'll be able to demonstrate a good grasp of the fundamentals of software engineering, along with a solid understanding of the specific platform they'll be working with. Bonus points if the pull request introduces a couple subtle bugs they'll need to ferret out :)