Bricks-haml is a project mainly written in JavaScript, it's free.
HAML renderer for Bricks.js
// Bricks Example: var hamlPlugin = require('./hamlhandler');
var values = { title: "Hello HAML" };
appServer.addRoute("/index$", hamlPlugin, { file: 'index.haml', data: values });
// HAML file: !!! %html %title=title %body %h1.title=title