Django’s release numbering works as follows:
An exception to this version numbering scheme is the pre-1.0 Django code. There’s no guarantee of backwards-compatibility until the 1.0 release.
In Subversion, each Django release will be tagged under tags/releases. If it’s necessary to release a bug fix release or a security release that doesn’t come from the trunk, we’ll copy that tag to branches/releases to make the bug fix release.
Major releases (1.0, 2.0, etc.) will happen very infrequently (think “years”, not “months”), and will probably represent major, sweeping changes to Django.
Minor release (1.1, 1.2, etc.) will happen roughly every six months – see release process, below for details.
These releases will contain new features, improvements to existing features, and such. A minor release may deprecate certain features from previous releases. If a feature in version A.B is deprecated, it will continue to work in version A.B+1. In version A.B+2, use of the feature will raise a PendingDeprecationWarning but will continue to work. Version A.B+3 will remove the feature entirely.
So, for example, if we decided to remove a function that existed in Django 1.0:
Micro releases (1.0.1, 1.0.2, 1.1.1, etc.) will be issued at least once half-way between minor releases, and probably more often as needed.
These releases will always be 100% compatible with the associated minor release – the answer to “should I upgrade to the latest micro release?” will always be “yes.”
Each minor release of Django will have a “release maintainer” appointed. This person will be responsible for making sure that bug fixes are applied to both trunk and the maintained micro-release branch. This person will also work with the release manager to decide when to release the micro releases.
At any moment in time, Django’s developer team will support a set of releases to varying levels:
As a concrete example, consider a moment in time halfway between the release of Django 1.3 and 1.4. At this point in time:
Django uses a time-based release schedule, with minor (i.e. 1.1, 1.2, etc.) releases every six months, or more, depending on features.
After each previous release (and after a suitable cooling-off period of a week or two), the core development team will examine the landscape and announce a timeline for the next release. Most releases will be scheduled in the 6-9 month range, but if we have bigger features to development we might schedule a longer period to allow for more ambitious work.
Each release cycle will be split into three periods, each lasting roughly one-third of the cycle:
The first phase of the release process will be devoted to figuring out what features to include in the next version. This should include a good deal of preliminary work on those features – working code trumps grand design.
At the end of part one, the core developers will propose a feature list for the upcoming release. This will be broken into:
Anything that hasn’t got at least some work done by the end of the first third isn’t eligible for the next release; a design alone isn’t sufficient.
The second third of the release schedule is the “heads-down” working period. Using the roadmap produced at the end of phase one, we’ll all work very hard to get everything on it done.
Longer release schedules will likely spend more than a third of the time in this phase.
At the end of phase two, any unfinished “maybe” features will be postponed until the next release. Though it shouldn’t happen, any “must-have” features will extend phase two, and thus postpone the final release.
Phase two will culminate with an alpha release.
The last third of a release is spent fixing bugs – no new features will be accepted during this time. We’ll release a beta release about halfway through, and an rc complete with string freeze two weeks before the end of the schedule.
After a minor release (i.e 1.1), the previous release will go into bug-fix mode.
A branch will be created of the form branches/releases/1.0.X to track bug-fixes to the previous release. When possible, bugs fixed on trunk must also be fixed on the bug-fix branch; this means that commits need to cleanly separate bug fixes from feature additions. The developer who commits a fix to trunk will be responsible for also applying the fix to the current bug-fix branch. Each bug-fix branch will have a maintainer who will work with the committers to keep them honest on backporting bug fixes.
Let’s look at a hypothetical example for how this all first together. Imagine, if you will, a point about halfway between 1.1 and 1.2. At this point, development will be happening in a bunch of places:
Sep 20, 2009