Ask HN: Interview for a Platform Engineer

I understand that this can be a broad job title these days but we're trying to hire a Platform'ish engineer for a team that also has typical SRE sort of responsibilities and I struggle with the kind of interview questions we should be using the vet the candidates.

A traditional programming interview would consist of maybe an algorithmic problem or maybe a design problem but what do people use for Platform/SRE sort of roles ?