The Leonardo was one of our favorite Arduinos. Unfortunately it has been discontinued. But fear not! The folks at Seeed Studio have designed the 32U4-based Seeeduino Lite as a worthy replacement.
There is one little problem though. The Zumo chassis has a couple of unfortunately placed capacitors that interfere with the DC jack and capacitors on the Seeeduino. The good news is that the Seeeduino ships without headers installed. So all you need to do is replace them with slightly longer headers. The Arduino R3 Stacking Headers are just the thing we need.