main.coffee

t = new Transaction()
t.start()

Order.coffee

class Order
  start: (callback) ->
    callback someDataFetchedFromInterwebs

Transaction.coffee

class Transaction

  @status = "created"
  @orders = [
    new Order()
    new Order()
    new Order()
  ]
    
  start: ->
    console.log "starting transaction!"
    
    stupidName = (i=0) => @orders[i].start callback i

    callback = (i) => (data) => 
      console.log i, data
      if @orders[ ++i ]?
        @status = "order_" + i
        stupidName i

      else 
        @status = "done"
        console.log "END"

    console.log "RUN"
    stupidName()