A computer system is used to create an application. An executable application is converted into an in-memory object representation. The in-memory object representation may be annotated with human-readable labels. The in-memory object representation and human readable labels may be stored in a storage device. At least one attribute of the in-memory object representation is selected for modification. At least one modification is performed on the in-memory object representation of the application. The modified representation is used to create an executable application.