Q(https://github.com/kriskowal/q) example

q.coffee

Q = require 'q'

total = 0
 
delay = (ms) =>
  deferred = Q.defer()
  setTimeout( =>
    total = total + ms
    console.log "Delayed #{ms} msec. Spent #{total} msec."
    deferred.resolve()
  , ms)
  deferred.promise
 
h1 = delay(100)
h1.then(-> delay 200)
  .then(-> delay 300)
  .then(-> delay 300)
  .done(-> console.log "done")

$ coffee q.coffee                                                                                                                                ~/n master
Delayed 100 msec. Spent 100 msec.
Delayed 200 msec. Spent 300 msec.
Delayed 300 msec. Spent 600 msec.
Delayed 300 msec. Spent 900 msec.
done