Barry Warsaw writes:
I've heard that Debian is working on Ubuntu-like PPAs. That would seem like a fruitful way of providing the entire stack for older distros.
This is already possible to some extent, as I mentioned earlier: one can enable more recent versions of packages from the Debian repositories, or (as I do) upgrade the distribution but pin packages which you need to be invariant to specific versions. It's also easy to build Debian packages in most cases if you just want to use more recent versions of upstream source. And there really isn't any difficulty in creating a PPA per se, you just add it to your sources list. The software can already handle it I'm pretty sure.
The problem is that PPAs just aren't acceptable in many cases for two reasons: (1) they are by definition not subject to distribution QA, and they may not be acceptable to enterprise QA, and (2) if you go to a PPA for Python 3.4, you will also need a 3.4-specific compile of each Python package you depend on, which means packages for those too in most distributions (and specifically in Debian, I believe). (And I'll address (3) "effort" below.)
In the case of (2), you can use the source debs and pretty easily modify them to use Python 3.4 instead of the specified Python (in fact, there probably is a generic source deb for this purpose). Or you can backport Mailman to Python 3.2. But either means that there is *zero* QA for Python 3.4 vs 3.2 (or whatever) differences. Someone who is using Debian stable evidently cares about that risk, and cares *a lot*.
Personally, I don't see why we should put in the effort to deal with this. If there are a lot of admins on wheezy systems who are systemd refuseniks (and I sympathize with them, systemd as described in Lennart's blogs is a great idea, but it suffers from mission creep on a Vietnam-sized scale), then there's enough manpower to create a "Mailman 3 on wheezy" PPA, and mailman-devel and mailman-users (not to forget python-list and maybe even python-dev) will be there to help with Mailman-specific issues in the packages.
If there aren't, then why should Mailman supply the manpower to satisfy a small number cranky admins? I suppose most admins will trust that by the time Debian stable gets systemd and Mailman 3, both Mailman and systemd will be good and stable themselves. So as I wrote to Tanstaafl before, TISATAFS but TANSTAAFL! (NB FVO F (speech) != F (beer).) Somebody will pay for this lunch; in this case I think the diners should do it. Mailman itself would get nothing but pain and a big "thank you" (ie, hot air).