Custom Deferrer. It doesn’t support errors, because, you know, fix them… You shouldn’t code errors to begin with.

app.coffee

doThis = (deferrer) ->
  # do some JS nifty things
  deferrer.done('foo', 'bar')

doThat = (deferrer) ->
  # Have callbacks/timeouts/async? Sure!
  setTimeout ->
    deferrer.done('foozle', 'barzle')
  , 5000

new Deferrer [doThis, doThat], (data) ->
  # Happens after 5 seconds
  console.log(data)
  # => { foo: 'bar', foozle: 'barzle' }

deferrer.coffee

class Deferrer

  constructor: (actions, @callback) ->
    @queue = actions.length
    @data = {}

    for action in actions
      action(this)

  done: (key, value) ->
    @queue--
    @data[key] = value

    this.callback(@data) if @queue is 0