gistfile1.coffee

createAttributeMonitor = ->
  monitored = Object.create null

  (parentModel, name) ->
    bubbleEvent = (event, args...) ->
      return unless event.startsWith 'change:'
      parentModel.trigger "change:#{name}.#{event[7..]}", args...

    value = parentModel.get name
    oldValue = monitored[name]

    if oldValue?
      return if value is oldValue
      oldValue.off 'all', bubbleEvent

    if value instanceof Backbone.Model or value instanceof Backbone.Collection
      monitored[name] = value
      value.on 'all', bubbleEvent

gistfile2.coffee

class BubbleModel extends Backbone.Model
  initialize: ->
    super
    monitor = createAttributeMonitor()

    # Bind to initial attributes.
    monitor @, name for name of @attributes

    # Watch for changes to attributes and rebind as necessary.
    @on 'change', =>
      monitor @, name for name of @changed