I have found the most reliable measure for a candidate is looking at their public interactions/contributions. Seeing what projects they choose to work on in the

I have found the most reliable measure for a candidate is looking at their public interactions/contributions. Seeing what projects they choose to work on in their spare time, how they speak at user groups, how they interact on an "issue" online. Blog posts are also great. For me, ability to communicate is such a huge part of being a successful developer, that being able to see how they communicate is always a very strong signal of intelligence, mastery, and interpersonal style. So this works great for people that partake in such things, but there are clear still many great developers (perhaps the vast majority) that don't have this type of extensive public profile. These are the applicants that I fear false-negatives for the most, and the candidates for which I am not confident of my interview techniques. Could it be that the proper way to technically interview such a candidate is to offer them a "fellowship" to work on an open-source project? Point them at any project (used by the company or a favorite project of their own) that they'd like to contribute to, and offer them a small stipend and enough time to make a legitimate contribution to open source? And use that as the technical portion of the interview?