Enterprise applications are complex, reflecting the complexity of the environments they exist in and support. The ``enterprise" is often a large corporation with many subsidiaries, each of which may have been acquired as a previously-independent company with its own product lines and business processes. With each acquisition, an enterprise inherits new ``legacy" systems, which must be integrated or phased out. Databases and applications are legion, system administration is vital. There are multiple developers, some inside the company, some outside, some from different divisions. Repetition is everywhere, but also variation. For example: the New York database is on the same back-end as the one in London, but the data model is slightly different, and the time zones on stored dates are different. One thing doesn't vary, however: the users want new functionality, and they want it yesterday.
In such an environment, non-functional requirements - the ``ilities" of development - reign supreme. Reusability, configurability, flexibility, extensibility, reliability, portability: these are the stuff ``enterprise" applications must be made of. The authors of PEAK have built their professional reputations not only on their applications' reliabilty, but on their speed of development as well. So PEAK incorporates their best ideas for making application components highly reusable, extensible, and configurable, ``right out of the box".