Industry leaders such as David Liddle, Jonathan Seybold, and many others have been talking about the coming age of modular applications for years. With its AppKit and Interface Builder, NeXT has taken us there, at least in the area of user-interface design.
To have modularity, there must be an application program interface (API) Ð a protocol that acts as a unifying framework. In the domain of publishing applications, Archetype has developed such a framework, the Document Engine, to promote the development of modular, component publishing applications.
The Document Engine can be thought of as a publishing-oriented extension to a computer's operating system. It provides at least four advantages for developers and users:
Rapid application development. By using a standard document object that can reduce the effort of building the document-manipulation portions of an application, the Document Engine allows publishing apps to be produced five times faster. They can also be developed by end users and small systems integrators Ð people for whom creating a major application is otherwise unthinkable.
Modular components. Small apps can be built for vertical applications that have not been addressed by the monolithic shrinkwrapped approach. These apps are themselves modular, and new kinds of objects and capabilities can be added to them.
Portable documents. Documents can be moved from workstation to workstation and from application to application and still be revisable. Users have their choice of application.
Workgroup publishing. Applications in a distributed network can edit the same document at the same time (with locking at the object level). Version control, journaling, archiving, and other capabilities can be easily added, since the document is its own database.
Of course, the Document Engine is not the only engine technology relevant to the world of publishing. Image-processing engines such as Pixar's IceMan promise to revolutionize the image-manipulation application area in much the same way; it offers a unifying framework for a certain class of applications.
It is not surprising that some developers have resisted the modular approach, since the advantages come at a price: You have to rewrite and restructure your application. This is not taken lightly by vendors of existing applications. Then again, switching to object-oriented programming in general has not been done without total rewrites either.
Paul Trevithick is the president of Archetype Software.