Show HN: Stepping stones puzzle implemented as a game

I'm a big fan of the stepping stones programming puzzle due to its simple rules, as posted on Al Zimmerman's contests: http://azspcs.com/Contest/SteppingStones

So I made it into a little web game available here: http://steppinston.es/

Made with PIXI.js, should be playable both on desktop and mobile. Please let me know what you think!