1. An application development system, comprising: a referencing component configured to reference an external component in an external development environment and to read type information for the referenced external component; and an authoring component configured to aid a user in authoring an application, the authoring component using the type information read from the referenced external component and using a language extension that allows external objects corresponding to the external component to be created by an external runtime environment and which allows methods to be invoked on the external objects and object declarations.