Just wanted to follow up and thank everybody for their suggestions. As you may know I went for Urlang, since it fit into Racket, which I was already using, and didn't require that I install Node.js (not a fan...).
The reason why I was looking to run it in the web browser was because I wanted to lower the barrier for people to play and rate my games. It turned out even better than I hoped -- nearly everyone eligible was able to take a look. So I did get lots of ratings!
Next time, I'll work on getting better ones! ; - )