I’m in the fortunate position of interviewing developers for the Identity team at Mozilla. I’m not sure how common it is for a designer to interview a developer, but that’s how we do. I queried Twitter “Designers: When interviewing a developer for your team, what are your best questions for finding out if you’ll work well together?” Here are the excellent responses.
===UPDATE 11/27===
I neglected to specify that of course, I’m not the *only* person interviewing developers. That would just be ludicrous. The majority of the people interviewing any given candidate will share the same skillset. Then a few others from the project team will ensure culture fit. Mozilla typically does two or three phone screens and approximately six in-person interviews.

3 comments
Justin Dolske says:
Nov 26, 2012
Good questions, if somewhat basic. (Or maybe we just hire exceptional developers for the Firefox front-end team.
But it does make we wonder what would be good design-related questions to ask as more in-depth followups when you’re looking for a developers with _strong_ design skills. Hmm.
P.S. Did I mention we’re hiring developers with design chops?
http://careers.mozilla.org/en-US/position/omgDWfwV
Shawn H Corey says:
Nov 27, 2012
How to interview a developer? Get another developer to do it. Only those with experience in the field can tell if the person is good or just bullshitting. But what question should a designer ask? Try: What is fluid design? If they know what that is, then you can (eventually) convince them of your design. ☺
Larissa says:
Dec 6, 2012
I’ve found that just asking whether they’ve worked with a designer in the past is enlightening. Then I ask them about the experience, what was successful and not successful in working together, what they learned from it, and how they deal with disagreements or trade-offs.
I think the important thing is to find an engineer who will value the contributions of a designer, not necessarily to discover what the engineer’s design chops are. (This is of course unless the engineer is going to do design work aside from engineering).