gistfile1.txt

class Zappa
  constructor: ->
    ...
    @locals =
      app: (name,server) => @app name,server
    ...

  app: (name,server) ->
    @ensure_app name,server
    @current_app = @apps[name]

  ...

  ensure_app: (name,server) ->
    @apps[name] = new App(name,server) unless @apps[name]?
    @current_app = @apps[name] unless @current_app?

class App
  constructor: (@name,configure) ->
    ...
    @http_server.configure =>
      if configure?
        configure @http_server
      else
        ... /* default */