Interchange is a highly-complex but very powerful web application server focused on ecommerce. It is built on the power of Perl, using many of its standard modules and capabilities while defining many more.
While Interchange focuses on e-commerce, it is really a general-purpose database access, retrieval, and templating systems. Besides online stores, here are some of the applications have been built on top of it:
Auction Calendar Configuration management Content management Document archival and rental Guestbook Image archival and download Intranet MP3 jukebox Poll Quiz Software repository Web log
This reference attempts to illuminate the source code of Interchagne and how you can write Perl enhancements, gadgets, and applications that integrate with Interchange.