We are looking for a third developer. I have reviewed the applications, conducted initial on-site interviews with the most interesting applicants (classic interview questions, FizzBuzz etc.) and, thus, finally reduced the number of potential candidates to two.
Now I want to reduce the risk of the new developer not getting along with the team (i.e. the two existing developers). To do that, I'd like to invite the remaining candidates (separately) to meet with the team, have a chat, and find out if there are any problems on a personal level.
As soon as I propose that to the team, the question "What are we supposed to talk about with him/her?" will come up, and I need a good answer. I don't want the interview to become awkward to either the candidate or the team.
My initial ideas were:
"Ask technical interview questions." Not applicable, since this is a junior position, both candidates would need to learn the technologies we are using, and (I think) I already verified in the first interview that they are smart and able to think logically (as far as this is possible in a single interview).
"Ask personality interview question." They are developers, not psychologists or trained HR people.
"Just do some small talk." They are developers. I cannot expect them to just improvise some small talk with an unknown person for an hour without feeling bored or thinking about the work they'd much rather get done in that time.
"Work on some real problem together." Introduction to our development tools or a specific problem domain would probably take a lot of time.
Any other ideas? Any experience with what works/what doesn't? As stated above, the primary goal is to make sure that they will be able to work together on a personal level.
(In case it's relevant: The duties will be classic "coding" (new features as well as maintenance of legacy code), customer support, and, after some experience has been gained, customer requirement analysis and software design.)