Invisible.js

Invisible.js works on top of your express app leveraging browserify to allow your domain models to work seamlessly in the client and the server.

Invisible = require("invisible");
crypto = require("crypto");
_s = require("underscore.string");

function Person(firstName, lastName, email){
    this.firstName = firstName;
    this.lastName = lastName;
    this.email = email;
}

Person.prototype.fullName = function(){
    return this.firstName + ' ' + this.lastName;
}

Person.prototype.getAvatarUrl = function(){
    cleanMail = _s.trim(this.email).toLowerCase();
    hash = crypto.createHash("md5").update(cleanMail).digest("hex");
    return "http://www.gravatar.com/avatar/" + hash;
}

module.exports = Invisible.createModel("Person", Person);

Require as usual in the server:

Invisible = require("invisible")
john = new Invisible.Person("John", "Doe", "john.doe@mail.com");
john.fullName(); //John Doe

In the client, just add the invisible script:

<script src="invisible.js"></script>
<script>
    jane = new Invisible.Person("Jane", "Doe", "jane.doe@mail.com");
    alert(jane.fullName()); //Jane Doe
</script>

Voilà! Restful API, MongoDB persistence, client and server validations and real-time events all come for free! See the github project for a full reference.