[vogtb]

A company I used to work for a few years ago did it pretty well.

To begin with, we agreed on who is asking questions if there were multiple rounds for the interview. If I recall correctly, it was just a straight up spreadsheet with the people interviewing, questions to ask, goal of questions, and possible follow ups. These are questions tailored to the engineer using things on their resume. Instead of being like "tell me about a time you showed leadership" questions (which suck) the questions were about specific things on their resume. Eg: "Susan will ask about how they built a replacement for their payment processing platform, with the goal of seeing if they can describe the challenges of leading a team end-to-end on a project."

For the white-board interviews, we did mock white-board interviews with my current coworkers. These were white-board questions that were less about a "right" answer, and more about how the candidate thinks about problems. By doing mock interviews with these problems, we achieved two things: we made sure we're asking questions that are useful (our current coworkers should be able to answer them) and we made sure that had answers to compare against the candidate. For example, if the candidate had an answer that sounded a lot like someone that we already worked with, then no one can say they "didn't pass" the question.

On the whole I think we spent about a 1:1 ratio of hours of preparation to hours of interviewing.