[rfc] six-month stable release cycles

[Stephen J. Turnbull]

Martin Pool writes:

 > I think if Python was shipping new features every month and
 > distributions shipped different selections from that series we would
 > see similar problem to those Bazaar is trying to address with
 > six-month cycles.

Sure.  N.B. I didn't say that Bazaar didn't make promises, I said that
Python does.  However the big difference here is that Python has a
much bigger stake in this kind of promise, since it's a platform
rather than an application, and as you point out, relatively mature.

And immaturity is the big problem you face: even your biggest fans are
going to be unsatisfied[1] with bzr-of-the-month for a while to come.
So you not only need backward compatibility in the sense of old repos
work with new bzr, you also need backward compatibility in the sense
of old repos upgrade to new formats painlessly 99.999999999999999999%
of the time (well, maybe you can shave off all but the first three of
those 9s :-), and interoperability between users with different
versions of bzr.  That's something that isn't often an issue for Python.

 > It can be argued (see the recent 'merge --preview' qbzr bug) that
 > plugins broken by bzrlib upgrades are buggy too.  But if the user is
 > left without a working setup this sounds like blame shifting.

Sure.  So if you think that the likely cause is a buggy plugin, you
just go help the author.  You do that anyway, right?  And if you were
wrong, admit it promptly and clearly.  I don't see why you lose any
credibility if you are clearly working with the plugin author to
resolve the problem.

If there are several unresolved problems, and there's no public
appearance of cooperation with the author(s), you need to be careful
about a generic claim of "that's usually a buggy plugin".  Rather,
"this looks like a buggy plugin and here's why."  You also should make
a publicly visible effort to improve API documentation when such bugs
are found in the plug-ins.

Seems to me you guys already do all that.  Do pay attention to which
way the wind's blowing, and every once in a while do something visible
to improve coordination with the plugin authors ... I don't see why
you'd have a credibility problem.  That's just me, but you know I'm no
fanboy!

Footnotes: 
[1]  In the sense of thirsting for the new features, not in the sense
of being unhappy.