It’s been a while since I subscribed to the XP mailing list, but I manage to hear about most of the important developments, I think. A few weeks ago, Dave Thomas told me about FIT, Ward Cunningham’s Framework for Integration Testing.

It sounded intriguing, but I really didn’t have time to investigate it. Then, at the Lone Star Software Symposium in early November, Daniel Steinberg mentioned FIT and how interesting it is. And last week, Mike Clark sent me a draft of some early work he’s done with FIT. By the rule of three, then, I suddenly had to spend the time on it … when three people of that caliber are talking about something, it deserves attention.

And FIT does deserve attention. Ward designed it to address one of the more difficult parts of Extreme Programming: the idea that customers should specify—and ideally write—automated acceptance tests. FIT is a fascinating approach to that problem. Naturally, the programmers must help, but they help in very small ways; primarily by writing tiny, simple adapter classes that hook application objects into FIT.

FIT is still in the early stages, and there are numerous problems to be solved. But it has the potential to work really well, at least partly because it is simple and adaptable rather than feature-complete and all-encompassing. If you haven’t looked at it and played with it, make the time to do so.