[Python-Dev] Some data points for the "annual release cadence" concept

[Nick Coghlan]

Hi folks,

Given the discussion of adopting an annual release cadence at the language
summit this year [1], this recent Jakarta (nee Java) EE announcement caught
my attention:
https://www.eclipse.org/ee4j/news/?date=2018-06-08#release-cadence

JEE are switching to an annual update cadence for the base platform, with
quarterly updates for individual components.

Since we last seriously discussed potential release cadence changes back in
2012 (with PEPs 407 and 413 [2,3]), that means JEE joins GCC switching to
an annual release cadence from GCC 5 back in 2015 (see [4]), while
clang/LLVM have been doing twice-annual feature releases for several years
now [5].

Most directly relevant to Python would be the Node.js maintenance lifecycle
initially developed in 2013, and evolved since then:
https://github.com/nodejs/Release

That's quite a fast lifecycle (even faster than we're considering - they do
a release every 6 months, with every 2nd release being supported for 3 1/2
years), but one of the keys to making it work in practice is
https://github.com/nodejs/nan

The gist of the "Native Abstractions for Node.js" project is that it aims
to provide a stable API & ABI for third party libraries to link against,
but *without* having to keep those interfaces stable in V8/Node.js itself.

In the Python world, the closest current equivalent would by SIP for PyQt
projects [6], which provides a shim layer that allows version independent
extension modules to target CPython's native stable ABI with the aid of a
single version specific dependency (so only the "sip" wheel itself needs to
be rebuilt for each new Python version, not every extension module that
depends on it).

So I expect a release cadence change would be a lot more viable now than it
would have been 6 years ago, but I also suspect actually getting there will
require a non-trivial amount of effort invested in generalising the SIP
model such that the stable ABI gets a *lot* easier for projects to
realistically target (including for cffi and Cython generated extension
modules).

Cheers,
Nick.

[1] https://lwn.net/Articles/755224/
[2] https://www.python.org/dev/peps/pep-0407/
[3] https://www.python.org/dev/peps/pep-0413/
[4] https://gcc.gnu.org/releases.html
[5] https://releases.llvm.org/ (Note: LLVM switched to twice-yearly X.0.0
releases in 2017, but were doing twice yearly X.Y releases for some time
before that)
[6] https://pypi.org/project/SIP/


-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-dev/attachments/20180612/5828eb62/attachment.html>