This guide is a comprehensive resource for :ref:`contributing <contributing>` to Python -- for both new and experienced contributors. It is :ref:`maintained <helping-with-the-developers-guide>` by the same community that maintains Python. We welcome your contributions to Python!
Here are the basic steps needed to get :ref:`set up <setup>` and contribute a patch. This is meant as a checklist, once you know the basics. For complete instructions please see the :ref:`setup guide <setup>`.
Install and set up :ref:`Git <vcsetup>` and other dependencies (see the :ref:`Git Setup <setup>` page for detailed information).
Fork the CPython repository to your GitHub account and :ref:`get the source code <checkout>` using:
git clone https://github.com/<your_username>/cpython cd cpython
Build Python, on UNIX and Mac OS use:
./configure --with-pydebug && make -jand on Windows use:
PCbuild\build.bat -e -d
See also :ref:`more detailed instructions <compiling>`, :ref:`how to install and build dependencies <build-dependencies>`, and the platform-specific pages for :ref:`UNIX <unix-compiling>`, :ref:`Mac OS <MacOS>`, and :ref:`Windows <windows-compiling>`.
:doc:`Run the tests <runtests>`:
./python -m test -j3On :ref:`most <mac-python.exe>` Mac OS X systems, replace :file:`./python` with :file:`./python.exe`. On Windows, use :file:`python.bat`.
Create a new branch where your work for the issue will go, e.g.:
git checkout -b fix-issue-12345 main
If an issue does not already exist, please create it. Trivial issues (e.g. typo fixes) do not require any issue to be created.
Once you fixed the issue, run the tests, run
make patchcheck, and if everything is ok, commit.Push the branch on your fork on GitHub and :doc:`create a pull request <pullrequest>`. Include the issue number using
bpo-NNNNin the pull request description. For example:bpo-12345: Fix some bug in spam moduleAdd a News entry into the
Misc/NEWS.ddirectory as individual file. The news entry can be created by using blurb-it, or the blurb tool and itsblurb addcommand. Please read more aboutblurbin :ref:`documentation <documenting>`.
Note
First time contributors will need to sign the Contributor Licensing Agreement (CLA) as described in the :ref:`Licensing <cla>` section of this guide.
Here are some links that you probably will reference frequently while contributing to Python:
- Issue tracker
- Buildbot status
- :doc:`help`
- PEPs (Python Enhancement Proposals)
- :doc:`gitbootcamp`
| Branch | Schedule | Status | First release | End-of-life | Release manager |
|---|---|---|---|---|---|
| main | PEP 664 | features | 2022-10-03 | 2027-10 | Pablo Galindo Salgado |
| 3.10 | PEP 619 | bugfix | 2021-10-04 | 2026-10 | Pablo Galindo Salgado |
| 3.9 | PEP 596 | bugfix | 2020-10-05 | 2025-10 | Łukasz Langa |
| 3.8 | PEP 569 | security | 2019-10-14 | 2024-10 | Łukasz Langa |
| 3.7 | PEP 537 | security | 2018-06-27 | 2023-06-27 | Ned Deily |
| 3.6 | PEP 494 | security | 2016-12-23 | 2021-12-23 | Ned Deily |
Dates in italic are scheduled and can be adjusted.
The main branch is currently the future Python 3.11, and is the only branch that accepts new features. The latest release for each Python version can be found on the download page.
Status:
| features: | new features, bugfixes, and security fixes are accepted. |
|---|---|
| prerelease: | feature fixes, bugfixes, and security fixes are accepted for the upcoming feature release. |
| bugfix: | bugfixes and security fixes are accepted, new binaries are still released. (Also called maintenance mode or stable release) |
| security: | only security fixes are accepted and no more binaries are released, but new source-only versions can be released |
| end-of-life: | release cycle is frozen; no further changes can be pushed to it. |
See also the :ref:`devcycle` page for more information about branches.
By default, the end-of-life is scheduled 5 years after the first release, but can be adjusted by the release manager of each branch. All Python 2 versions have reached end-of-life.
We encourage everyone to contribute to Python and that's why we have put up this developer's guide. If you still have questions after reviewing the material in this guide, then the Core Python Mentorship group is available to help guide new contributors through the process.
A number of individuals from the Python community have contributed to a series of excellent guides at Open Source Guides.
Core developers and contributors alike will find the following guides useful:
Guide for contributing to Python:
Advanced tasks and topics for once you are comfortable:
- :doc:`silencewarnings`
- Fixing issues found by the :doc:`buildbots <buildbots>`
- :doc:`coverity`
- Helping out with reviewing open pull requests. See :ref:`how to review a Pull Request <how-to-review-a-pull-request>`.
- :doc:`fixingissues`
It is recommended that the above documents be read as needed. New contributors will build understanding of the CPython workflow by reading the sections mentioned in this table. You can stop where you feel comfortable and begin contributing immediately without reading and understanding these documents all at once. If you do choose to skip around within the documentation, be aware that it is written assuming preceding documentation has been read so you may find it necessary to backtrack to fill in missing concepts and terminology.
Improving Python's code, documentation and tests are ongoing tasks that are never going to be "finished", as Python operates as part of an ever-evolving system of technology. An even more challenging ongoing task than these necessary maintenance activities is finding ways to make Python, in the form of the standard library and the language definition, an even better tool in a developer's toolkit.
While these kinds of change are much rarer than those described above, they do happen and that process is also described as part of this guide:
This guide is specifically for contributing to the Python reference interpreter, also known as CPython (while most of the standard library is written in Python, the interpreter core is written in C and integrates most easily with the C and C++ ecosystems).
There are other Python implementations, each with a different focus. Like CPython, they always have more things they would like to do than they have developers to work on them. Some major examples that may be of interest are:
- PyPy: A Python interpreter focused on high speed (JIT-compiled) operation on major platforms
- Jython: A Python interpreter focused on good integration with the Java Virtual Machine (JVM) environment
- IronPython: A Python interpreter focused on good integration with the Common Language Runtime (CLR) provided by .NET and Mono
- Stackless: A Python interpreter focused on providing lightweight microthreads while remaining largely compatible with CPython specific extension modules
- Issue tracker
- Meta tracker (issue tracker for the issue tracker)
- :doc:`experts`
- Buildbot status
- PEPs (Python Enhancement Proposals)
- :doc:`help`
- :doc:`developers`
- Anyone can clone the sources for this guide. See :ref:`helping-with-the-developers-guide`.
- Tool support
- :doc:`gdb`
- :doc:`clang`
- Various tools with configuration files as found in the Misc directory
- Information about editors and their configurations can be found in the wiki
- python.org maintenance
- :ref:`Search this guide <search>`
Please note that all interactions on Python Software Foundation-supported infrastructure is covered by the PSF Code of Conduct, which includes all infrastructure used in the development of Python itself (e.g. mailing lists, issue trackers, GitHub, etc.). In general this means everyone is expected to be open, considerate, and respectful of others no matter what their position is within the project.
.. toctree::
:maxdepth: 3
setup
help
pullrequest
runtests
coverage
docquality
documenting
silencewarnings
fixingissues
tracker
triaging
communication
porting
coredev
developers
committing
devcycle
buildbots
stdlibchanges
langchanges
experts
gdb
exploring
grammar
parser
compiler
garbage_collector
extensions
c-api
coverity
clang
buildworker
motivations
gitbootcamp
appendix