Now http://www.espruino.com/binaries/travis/master/ does not even have a file for puck js.
Looks like there was a build glitch. Totally untested, but you can try the attached build :)
@jameshollyer started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Now http://www.espruino.com/binaries/travis/master/ does not even have a file for puck js.