[Python-Dev] Re: Stability and change

Guido van Rossum guido@python.org
Sat, 06 Apr 2002 23:11:27 -0500

> Perhaps the whole PythonLabs crew should have an in-person
> brainstorming session to kickstart the goalmaking process?

Why should this be PythonLabs' internal brainstorm?  We may be the
only ones who get paid directly to maintain Python (part time, the
rest is Zope work!), but we're not its only maintainers.  This
concerns us (active developers) all, because we're all limited

> What's Zope doing to handle this issue?

Assuming you mean "how is change in the Zope software handled" (rather
than "how does Zope Corporation handle change in Python"), they have a
rather different approach.

There's an effort to create a Zope 3 which is a total rewrite,
(almost) completely from scratch.  There's an explicit compatibility
requirement for the end result, but that's only needed in the final
phase -- while it's being created (with lots of help from the Zope
community) it can do whatever it wants.

In the mean time, various previous Zope releases are still being
maintained: I believe that both 2.4 and 2.5 are under active
maintenance, meaning that micro releases are occasionally issued, and
there's an effort underway to create a 2.6 release (again with
community help).

While there's a striving for easy upgrading from 2.x to 2.(x+1), each
new one (2.(x+1)) adds significant new features; I believe strict
compatibility between 2.x and 2.(x+1) is not a goal (except at the
storage level -- the database contents are sacred).  I believe that
it's very common for 3rd party products written against 2.x to require
significant porting effort to work with 2.(x+1).

The www.zope.org site for example runs a very old version of Zope (I
believe 2.3) because it's encrusted with much custom code that make an
upgrade difficult.  Instead, there's a completely new version in the
works (new.zope.org).

--Guido van Rossum (home page: http://www.python.org/~guido/)