Looks like it is built on Turbulenz (https://turbulenz.com/ https://turbulenz.com/), an html5 game engine that went open source last year. It is a quality engi

Looks like it is built on Turbulenz (https://turbulenz.com/ https://turbulenz.com/), an html5 game engine that went open source last year. It is a quality engine at this stage and a well done site.