RE: [Zope] - What constitutes a transaction?

Ty wrote:

and restart it, these changes are still there. My added methods have effect that is forgotten at shutdown, and they don't show up in the Undo list. I have another Product where my added methods do work correctly.

If the things that you change aren't Persistent, then the transaction manager isn't notified that state has changed. For instance, if you're method changes an attribute that is a standard Python dictionary, then the transaction manager doesn't see it. --Paul