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I attended the tutorial on Zope 3 that Jim Fulton gave before PyCon. Altogether I was impressed, though I still have reservations (though that's not the topic of this post).

Particularly noticeable is how friendly Zope 3 is to external modules. Not just friendly, but enthusiastic -- the contact module in the tutorial specifically has no special Zope 3 bits. (I'd link to it, but the tutorial is a PDF... blech.) The module is fit into the Zope system through "configuration". (And presumably more advanced integration would be done through adapters, which also serve to separate Zope-neutral code from Zope-3-specific code.)

I put scare quotes around "configuration" because it's different than I usually think of configuration. It's not the kind of thing a system administrator would do, or something that you would do to install or customize a product, but something for a system integrator -- which is fully a programming task.

Anyway, that's all very refreshing compared to Zope 2. But it's also all very different than Zope 2. And there's no concrete plan for facilitating migration from Zope 2 to Zope 3. (There is "Frankenzope", which seems to basically be Zope 3 and Zope 2 both running in the same process space, and off the same ZODB.) And Zope 3 isn't (at least as advertised) ready for production (despite a couple production deployments which have already occurred). So, if you are excited about Zope 3, but you are mostly interested in application development (rather than framework development, which where Zope 3 is right now), what are you to do? How do you get ready for Zope 3?

One nice thing is you don't have to get ready for Zope 3, except to make good domain objects. Later you'll have to add configuration and views and other stuff, but that's life -- and if they do Zope 3 right, it shouldn't be too hard. But (in my experience) Zope 2 does not facilitate the creation of nice, neutral domain objects. It encourages the creation of objects that are as much "Zope" objects as they are domain objects -- if anything, the objects' Zopeness dominates their domain aspect.

So it occurs to me that the best way to develop for Zope 3 is to not develop for Zope 2. You might want to use some pieces -- Page Templates and ZODB, but the bulk of the Zope 2 environment is not present in Zope 3 (or needed).

This is all kind of ironic.