When recruiting I tend to look for intelligence (looking at a problem from more than one angle) and engineering mindset (leverage critical thinking to solve the problem) over a skillset (Guru level Solidity developer).
I'd appreciate hearing what you guys think are good interview questions to mine a good engineer from a group of applicants.
I agree the demos are best, but great questions are simply to ask what they have done in the past when faced with ___ . Ask a bunch of probing questions for follow up. Then ask them another scenario. Be sure to look for the patterns in the answers - it's never about one word, or one bad or good thought, it's about the patterns. Most people get hung up on the details, but it's about the patterns.