An update on our last post, we have now completed a run of builds for Python 3.7 wheels for Raspbian Buster. Now, when you pip install something on Raspbian Buster, you’ll generally get a wheel for it, to the same extent you do for Jessie and Stretch.
We now host 40k Python 3.4 wheels (Jessie), 46k Python 3.5 wheels (Stretch) and 43k Python 3.7 wheels (Buster). We also host 1.1 million pure Python wheels, which work on any Python version. It’s amazing how few packages actually require compilation, but for the ones that do, having a wheel makes a big difference.
We’ve now moved the piwheels project source from my personal github account bennuttall/piwheels to a new organisation – piwheels/piwheels. GitHub is good at redirecting, so old links should generally work.
We also created a new repository for issues related to packages on piwheels.org, and moved any existing package issues to it, to separate them from issues with the piwheels source code. Now, issues related to packages should be filed at piwheels/packages. The links from project pages currently point at the old location, but the issue templates refer people to the right place. We’ll push an update soon and the project pages will be regenerated with the new URLs.
Python 3.8 is on the horizon. It’s in beta now, and expected to be released in October 2019. However, the piwheels project tends to only stick with what’s stable in Debian (i.e. 3.4 in Jessie, 3.5 in Stretch and 3.7 in Buster).
Debian Bullseye follows Buster, but it’s two years away (let’s say July 2021). As well as Python 3.8, 3.9 is also planned, with a scheduled release date in June 2020, plus the proposed introduction of a 9-month release cycle, potentially putting Python 3.10 at March 2021, perhaps in time for Debian Bullseye. But that’s two years away, so let’s wait and see.
In the 2 year period a Debian release is “current stable”, new Python versions are released, and people naturally want to use those straight away. It’s not recommended that you install an out-of-distribution Python version, as everything Python related in the distribution is built to match the system Python ABI, and things tend to break if you go against that. For that reason we won’t be building Python 3.8/3.9 wheels until they’re in a stable Debian release.
Having said that, now that Ubuntu are building OS images for the Pi, we may see newer Python versions in future Ubuntu releases (which are 6-monthly). If Python 3.8 is released in October, maybe Ubuntu 19.10 or 20.04 will include it. piwheels.org doesn’t build wheels for Ubuntu, so Ubuntu would need its own instance of piwheels providing wheels for Python versions supported in Ubuntu. I can image such a project arising in not-too-distant future.
Python 3.4 is pretty old hat now. pip, and many other projects don’t support it any more. However, Debian Jessie‘s EOL is a year away (June 2020), so I think we should continue to build packages with Jessie until that date. We’ll probably still host cp34m wheels after that but not build anything new. It’ll be the first ABI we deprecate.