[Distutils] Package install failures in 2.6.3 - setuptools vs Distribute

[Zooko Wilcox-O'Hearn]

I'm sorry to follow-up to my own post, but I realized that I didn't  
make something clear: the current Tahoe-LAFS source distribution  
comes with its own copy of setuptools, so even if PJE releases a new  
version of setuptools or if we patch that copy to work-around this  
problem, we're going to have to re-qualify the combination of the new  
version on our buildbot and make a new stable release of Tahoe-LAFS  
(something that typically only happens every 3 or 4 months) before  
end users will be able to install Tahoe-LAFS on Python 2.6.3.

I don't want to point fingers, because that goes nowhere.  Lots of  
people could have written their software or managed their processes  
differently in order to avoid this situation, including me.  However,  
I do want to emphasize that this is a serious problem.  Backwards  
compatibility on minor releases such as from 2.6.2 to 2.6.3 is a huge  
concern for a lot of people.  If something like this breaks --  
regardless of whose fault(s) it is -- then it reduces people's trust  
in the stability of stable updates of their infrastructural software.

I'm sorry to say that this event has already made me more hesitant to  
jump from setuptools to Distribute, just because some of the  
maintainers of Distribute have posted saying that they don't think  
this kind of thing is such a big deal.  I prefer to use packaging  
tools which are stable.  To achieve that kind of stability sometimes  
requires basically "taking responsibility" for other people's  
decisions, such as saying "Well, setuptools-0.6c9 monkey-patches  
distutils.  We think that's a bad idea and we wish it didn't do  
that.  But, we know that a lot of other people out there are relying  
on the combination of setuptools-0.6c9 and Python 2.6.x, so we're  
going to go the extra mile to make sure that those people don't  
experience disruptions.".

Please take this in the constructive spirit that is intended.  We're  
on the same team.  I've already contributed a few patches and a lot  
of bug reports to setuptools, Distribute, and Python, and I'd like to  
contribute more in the future.  Having a policy of actively working  
to maintain stability across stable updates will help everyone.

Regards,

Zooko