Ask HN: pairing in Ruby with someone who hasn't coded since Z80 Assembler?

The guy in question is very smart, & is a subject matter expert for a system I'm helping build in RoR + backbone.js. I've managed to persuade him to join in one of our Hack Days as a coder.

The catch is, the last code he cut was Assembler for a Z80, back when they were mainstream. He tells the most awesome story of when 'remote debugging' meant calling the security guard at a distant location & talking him through patching code at a terminal :-)

Does anyone have any suggestions for how to approach pairing? I'm thinking ping-pong pairing, combined with a gentle introduction to as few infrastructure items as possible (Git, rspec, bundler, TextMate).

Any advice or experience would be greatly appreciated ...