Adam Wiggins, per usual, is on to something. Values:
Sharing values is the most important part of effective collaboration. If you don’t have significant overlap on values between you and your teammates, you’re going to have a tough time getting anything accomplished.
I’m starting to think that figuring what the other person puts a premium on is the most important part of a technical interview. Is the other person passionate in the same way you are? Are the things they obsess over complimentary to what you would rather gloss over? If the answer to these questions is yes, you’ll probably make awesome things together.