Polymer modeling clay for node.js. A model schema definition with type validations, dirty-state tracking, and rollback. Models are optionally persistable to CouchDB using cradle, Redis, LevelUP, and Cassandra. Polyclay gives you the safety of type-enforcing properties without making you write a lot of boilerplate. Polyclay builds a model constructor function from options that you pass to its buildClass function, similar to the way Backbone builds constructors.