Hey, remember last month when I asked about releasing Cyrus v3.2 <https://lists.andrew.cmu.edu/pipermail/cyrus-devel/2019-November/004509.html>?
That thread had some more conversation about what needs to get done before v3.2, and I wanted to come back to it and turn some things on their head. Right now, we’re talking about Cyrus releases being feature-bound. “We’ll release v3.2 when feature X is done.” I think we’re not being well-served by that. As feature X is delayed (for various reasons that we can’t easily eliminate), it doesn’t just delay the feature, but also all the other minor bugfixes and optimizations that we’ve made in the master branch. Also, it sets up the idea that we delay releases for the sake of fixes, instead of releasing the fixes that are ready. That is: every additional criteria for a new release is another doorway to delay. Instead of opening those doors, I would rather try to eliminate all of them. I propose that instead of tying releases to milestones, we tie them to the calendar. For the sake of full disclosure: I am modeling this suggestion on the release cycle of perl <https://metacpan.org/pod/perlpolicy>, which I ran for several years. I found the process more than satisfactory, then. 1. A new *unstable release* of Cyrus is made every month. We promise only that it compiled and passed the Cassandane test suite on the release manager’s computer. It might contain regressions from previous unstable releases, it might have crashers or corruptors. We try to avoid any of these, but the goal here is a snapshot for easy month-to-month testing. These are the odd-middle-digit releases. (3.3.x) 2. A new *major release* of Cyrus is made every year. We will have tested it on as many configurations as we can readily test. We will have, some time before the release, frozen the branch for risky changes, to reduce churn. In the meantime, new work lives in feature branches. (The changelogs from each unstable release provide a good basis for the whole-year changelog!) These are the even-middle-digit third-digit-zero releases. (3.4.0) 3. A new *maintenance release* of Cyrus is made for the last two stable releases when there are enough fixes to critical bugs to warrant it. These are the even-middle-digit third-digit-nonzero releases (3.4.1) For the above to work, some more properties need to be maintained. Maintenance releases should be no-brainers to install, so they must only fix regressions, crashers, security vulnerabilities, and the like. This means that once you’re on 3.4.0, you can always upgrade within the 3.4 series with a minimum risk. It also means you get no optimizations, features, and the like. Major releases must clearly document any incompatible changes or upgrade steps required. Because non-regression bugfixes aren’t backported, we want everyone to be able to upgrade from major release to major release, so incompatible changes must be kept to a minimum. In part, this is just “don’t kill off a feature people use just because it’s a little annoying.” The more important one is “don’t introduce half-baked things that might need to change,” because people will come to rely on them before you get the updates finished. For features that will require multiple years to get right, they have to go behind a default-off configuration option. I’d strongly suggest they all have a uniform substring like “unstable”. That way, when a complaint comes in that the behavior of JMAP calendaring has changed, we can reply, “well, to use it, you had to turn on the unstable_jmap_calendaring” option. If we go with this policy, we’ll need to… 1. identify what issues are *blockers* to v3.2.0, meaning they’re regressions from v3.0 and would reasonably prevent someone from upgrading; this does *not* include all known bugs, since they may be bugs that already exist in the last stable release! 2. pick a release target for v3.2.0; I will arbitrarily suggest March 2 as “not too far off, but far off enough that we can get things in order”; also, if you’re American, March 2 is 3/2 ;-) 3. produce a changleog, and especially identify what changes in master need documentation as “incompatible changes” 4. produce a list of changes in master that should be put behind an unstable configuration option and then do it 5. decide when to stop merging non-release-related things to master 6. make a plan for who will do monthly snapshot releases I’ve spoken with ellie and Bron about just a few of these, such that I don’t think it’s all crazy. (ellie notes, correctly, I think, that the first set of releases like this will be the hard ones, where we work out things like “how do we keep track of incompatibilities, upgrade steps, and also how do we make snapshots dead easy to release.”) If there’s general agreement, I am definitely ready to pitch in and help try to make it work! — rjbs
