It is not always possible to complete the fixup operation until the STBInFiler>>#next has completed. For example, a hierarchy of windows must be created parent before child. The STBInFiler offers a #deferredAction: method which will perform the given niladic valuable (a MessageSend perhaps) on completion of the STBInFiler>>#next. So, in our hypothetical window hierarchy, the proxy representing the top parent window can defer the creation the real windows until all proxies have been loaded. If there is more than one deferred action then they are performed in the order in which they were issued.