Focus on reading the personality of the candidate for now. A solid personality almost invariably means a solid life-long learning attitude, which translates into skills that are forefront in industry.
You can have the best techologist with the worst personality, and he/she will do more damage than good.
It's a lot more difficult to find candidates with solid personalities than those with good tech skills.
As for vetting tech skills, you can't during the interview. Esp not in your position. But ask the candidate this:
"How do we know you're doing the right thing, technologically speaking?"
Ans: "Even if my managers don't know my tech stuff, I always install a workflow that conveniently and efficiently maintains 'full visibility'. Peer reviews will already spot my errors. In worst case, casual reviews of my recorded work months later can still call out my bluffs, even if my managers aren't entirely tech-savvy."
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