The pip project has a release cadence of releasing whatever is on
every 3 months. This gives users a predictable pattern for when releases
are going to happen and prevents locking up improvements for fixes for long
periods of time, while still preventing massively fracturing the user base
with version numbers.
Our release months are January, April, July, October. The release date within that month will be up to the release manager for that release. If there are no changes, then that release month is skipped and the next release will be 3 months later.
The release manager may, at their discretion, choose whether or not there will be a pre-release period for a release, and if there is may extend that period into the next month if needed.
Because releases are made direct from the
main branch, it is essential
main is always in a releasable state. It is acceptable to merge
PRs that partially implement a new feature, but only if the partially
implemented version is usable in that state (for example, with reduced
functionality or disabled by default). In the case where a merged PR is found
to need extra work before being released, the release manager always has the
option to back out the partial change prior to a release. The PR can then be
reworked and resubmitted for the next release.
Any change to pip that removes or significantly alters user-visible behavior that is described in the pip documentation will be deprecated for a minimum of 6 months before the change occurs.
Certain changes may be fast tracked and have a deprecation period of 3 months. This requires at least two members of the pip team to be in favor of doing so, and no pip maintainers opposing.
Deprecation will take the form of a warning being issued by pip when the feature is used. Longer deprecation periods, or deprecation warnings for behavior changes that would not normally be covered by this policy, are also possible depending on circumstances, but this is at the discretion of the pip maintainers.
Note that the documentation is the sole reference for what counts as agreed behavior. If something isn’t explicitly mentioned in the documentation, it can be changed without warning, or any deprecation period, in a pip release. However, we are aware that the documentation isn’t always complete - PRs that document existing behavior with the intention of covering that behavior with the above deprecation process are always acceptable, and will be considered on their merits.
pip has a helper function for making deprecation easier for pip maintainers.
The supporting documentation can be found in the source code of
pip._internal.utils.deprecation.deprecated. The function is not a part of
pip’s public API.
Python 2 Support¶
pip 20.3 was the last version of pip that supported Python 2. Bugs reported with pip which only occur on Python 2.7 will likely be closed as “won’t fix” issues by pip’s maintainers.
Python Support Policy¶
In general, a given Python version is supported until its usage on PyPI falls below 5%. This is at the maintainers’ discretion, in case extraordinary circumstances arise.
Use for features that will be deprecated. Deprecated features should remain available behind this flag for at least six months, as per the deprecation policy.
Features moved behind this flag should always include a warning that indicates when the feature is scheduled to be removed.
Once the feature is removed, users who use the flag should be shown an error.
Use for new features that users can test before they become pip’s default behaviour (e.g. alpha or beta releases).
Once the feature becomes the default behaviour, this flag can remain in place, but should issue a warning telling the user that it is no longer necessary.
Creating a new release¶
Ensure you have the latest
Create a new
mainand switch to it.
Prepare for release using
nox -s prepare-release -- YY.N. This will update the relevant files and tag the correct commit.
release/YY.Nbranch as a pull request and ensure CI passes. Merge the changes back into
mainand pull them back locally.
Build the release artifacts using
nox -s build-release -- YY.N. This will checkout the tag, generate the distribution files to be uploaded and checkout the main branch again.
Upload the release to PyPI using
nox -s upload-release -- YY.N.
Push the tag created by
get-pip.pyscript in the get-pip repository (as documented there) and commit the results.
Submit a Pull Request to CPython adding the new version of pip (and upgrading setuptools) to
Lib/ensurepip/_bundled, removing the existing version, and adjusting the versions listed in
If the release dropped the support of an obsolete Python version
M.m/get-pip.py needs to be published: update the
all task from
tasks/generate.py in get-pip repository and make a pull request to
psf-salt repository to add the new
get-pip.py (and its directory) to
get-pip.py script needs to be updated due to changes in pip internals
and if the last
M.m/get-pip.py published still uses the default template, make
sure to first duplicate
before updating it and specify in
now needs to use
Creating a bug-fix release¶
Sometimes we need to release a bugfix release of the form
order to create one of these the changes should already be merged into the
Create a new
release/YY.N.Z+1branch off of the
YY.Ntag using the command
git checkout -b release/YY.N.Z+1 YY.N.
Cherry pick the fixed commits off of the
mainbranch, fixing any conflicts.
nox -s prepare-release -- YY.N.Z+1.
Merge main into your release branch and drop the news files that have been included in your release (otherwise they would also appear in the
release/YY.N.Z+1branch to github and submit a PR for it against the
mainbranch and wait for the tests to run.
Once tests run, merge the
main, and follow the above release process starting with step 5.