Options

Setting options

cibuildwheel can either be configured using environment variables, or from config file such as pyproject.toml.

Environment variables

Environment variables can be set in your CI config. For example, to configure cibuildwheel to run tests, add the following YAML to your CI config file:

GitHub Actions

.github/workflows/*.yml (docs) (can be global, in job, or in step)

env:
  CIBW_TEST_REQUIRES: pytest
  CIBW_TEST_COMMAND: "pytest {project}/tests"

Azure Pipelines

azure-pipelines.yml (docs)

variables:
  CIBW_TEST_REQUIRES: pytest
  CIBW_TEST_COMMAND: "pytest {project}/tests"

Travis CI

.travis.yml (docs)

env:
  global:
    - CIBW_TEST_REQUIRES=pytest
    - CIBW_TEST_COMMAND="pytest {project}/tests"

AppVeyor

appveyor.yml (docs)

environment:
  global:
    CIBW_TEST_REQUIRES: pytest
    CIBW_TEST_COMMAND: "pytest {project}\\tests"

CircleCI

.circleci/config.yml (docs)

jobs:
  job_name:
    environment:
      CIBW_TEST_REQUIRES: pytest
      CIBW_TEST_COMMAND: "pytest {project}/tests"

Gitlab CI

.gitlab-ci.yml (docs)

linux:
  variables:
    CIBW_TEST_REQUIRES: pytest
    CIBW_TEST_COMMAND: "pytest {project}/tests"

Cirrus CI

.cirrus.yml (docs)

env:
  CIBW_TEST_REQUIRES: pytest
  CIBW_TEST_COMMAND: "pytest {project}/tests"

Configuration file

You can configure cibuildwheel with a config file, such as pyproject.toml. Options have the same names as the environment variable overrides, but are placed in [tool.cibuildwheel] and are lower case, with dashes, following common TOML practice. Anything placed in subsections linux, windows, or macos will only affect those platforms. Lists can be used instead of strings for items that are natually a list. Multiline strings also work just like in in the environment variables. Environment variables will take precedence if defined.

The example above using environment variables could have been written like this:

[tool.cibuildwheel]
test-requires = "pytest"
test-command = "pytest {project}/tests"

The complete set of defaults for the current version of cibuildwheel are shown below:

[tool.cibuildwheel]
build = "*"
skip = ""
test-skip = ""

archs = ["auto"]
build-frontend = "pip"
config-settings = {}
dependency-versions = "pinned"
environment = {}
environment-pass = []
build-verbosity = ""

before-all = ""
before-build = ""
repair-wheel-command = ""

test-command = ""
before-test = ""
test-requires = []
test-extras = []

container-engine = "docker"

manylinux-x86_64-image = "manylinux2014"
manylinux-i686-image = "manylinux2014"
manylinux-aarch64-image = "manylinux2014"
manylinux-ppc64le-image = "manylinux2014"
manylinux-s390x-image = "manylinux2014"
manylinux-pypy_x86_64-image = "manylinux2014"
manylinux-pypy_i686-image = "manylinux2014"
manylinux-pypy_aarch64-image = "manylinux2014"

musllinux-x86_64-image = "musllinux_1_1"
musllinux-i686-image = "musllinux_1_1"
musllinux-aarch64-image = "musllinux_1_1"
musllinux-ppc64le-image = "musllinux_1_1"
musllinux-s390x-image = "musllinux_1_1"


[tool.cibuildwheel.linux]
repair-wheel-command = "auditwheel repair -w {dest_dir} {wheel}"

[tool.cibuildwheel.macos]
repair-wheel-command = "delocate-wheel --require-archs {delocate_archs} -w {dest_dir} -v {wheel}"

[tool.cibuildwheel.windows]

Tip

Static configuration works across all CI systems, and can be used locally if you run cibuildwheel --platform linux. This is preferred, but environment variables are better if you need to change per-matrix element (CIBW_BUILD is often in this category, for example), or if you cannot or do not want to change a pyproject.toml file. You can specify a different file to use with --config-file on the command line, as well.

Configuration overrides

One feature specific to the configuration files is the ability to override settings based on selectors. To use, add a tool.cibuildwheel.overrides array, and specify a select string. Then any options you set will only apply to items that match that selector. These are applied in order, with later matches overriding earlier ones if multiple selectors match. Environment variables always override static configuration.

A few of the options below have special handling in overrides. A different before-all will trigger a new container to launch on Linux, and cannot be overridden on macOS or Windows. Overriding the image on linux will also trigger new containers, one per image. Some commands are not supported; output-dir, build/skip/test_skip selectors, and architectures cannot be overridden.

Examples:
[tool.cibuildwheel.linux]
before-all = "yum install mylib"
test-command = "echo 'installed'"

[[tool.cibuildwheel.overrides]]
select = "*-musllinux*"
before-all = "apk add mylib"

This example will override the before-all command on musllinux only, but will still run the test-command. Note the double brackets, this is an array in TOML, which means it can be given multiple times.

[tool.cibuildwheel]
# Normal options, etc.
manylinux-x86_64-image = "manylinux2014"

[[tool.cibuildwheel.overrides]]
select = "cp36-*"
manylinux-x86_64-image = "manylinux1"

[[tool.cibuildwheel.overrides]]
select = "cp3{7,8,9}-*"
manylinux-x86_64-image = "manylinux2010"

This example will build CPython 3.6 wheels on manylinux1, CPython 3.7-3.9 wheels on manylinux2010, and manylinux2014 wheels for any newer Python (like 3.10).

Options summary

Build selection

CIBW_PLATFORM

Override the auto-detected target platform

Options: auto linux macos windows

Default: auto

auto will auto-detect platform using environment variables, such as TRAVIS_OS_NAME/APPVEYOR/CIRCLECI.

  • For linux, you need Docker or Podman running, on Linux, macOS, or Windows.
  • For macos and windows, you need to be running on the respective system, with a working compiler toolchain installed - Xcode Command Line tools for macOS, and MSVC for Windows.

This option can also be set using the command-line option --platform. This option is not available in the pyproject.toml config.

Tip

You can use this option to locally debug your cibuildwheel config, instead of pushing to CI to test every change. For example:

export CIBW_BUILD='cp37-*'
export CIBW_TEST_COMMAND='pytest {package}/tests'
cibuildwheel --platform linux .

This is even more convenient if you store your cibuildwheel config in pyproject.toml.

You can also run a single identifier with --only <identifier>. This will not require --platform or --arch, and will override any build/skip configuration.

CIBW_BUILD, CIBW_SKIP

Choose the Python versions to build

List of builds to build and skip. Each build has an identifier like cp38-manylinux_x86_64 or cp37-macosx_x86_64 - you can list specific ones to build and cibuildwheel will only build those, and/or list ones to skip and cibuildwheel won't try to build them.

When both options are specified, both conditions are applied and only builds with a tag that matches CIBW_BUILD and does not match CIBW_SKIP will be built.

When setting the options, you can use shell-style globbing syntax, as per fnmatch with the addition of curly bracket syntax {option1,option2}, provided by bracex. All the build identifiers supported by cibuildwheel are shown below:

macOS Windows Linux Intel Linux Other
Python 3.6 cp36-macosx_x86_64 cp36-win_amd64
cp36-win32
cp36-manylinux_x86_64
cp36-manylinux_i686
cp36-musllinux_x86_64
cp36-musllinux_i686
cp36-manylinux_aarch64
cp36-manylinux_ppc64le
cp36-manylinux_s390x
cp36-musllinux_aarch64
cp36-musllinux_ppc64le
cp36-musllinux_s390x
Python 3.7 cp37-macosx_x86_64 cp37-win_amd64
cp37-win32
cp37-manylinux_x86_64
cp37-manylinux_i686
cp37-musllinux_x86_64
cp37-musllinux_i686
cp37-manylinux_aarch64
cp37-manylinux_ppc64le
cp37-manylinux_s390x
cp37-musllinux_aarch64
cp37-musllinux_ppc64le
cp37-musllinux_s390x
Python 3.8 cp38-macosx_x86_64
cp38-macosx_universal2
cp38-macosx_arm64
cp38-win_amd64
cp38-win32
cp38-manylinux_x86_64
cp38-manylinux_i686
cp38-musllinux_x86_64
cp38-musllinux_i686
cp38-manylinux_aarch64
cp38-manylinux_ppc64le
cp38-manylinux_s390x
cp38-musllinux_aarch64
cp38-musllinux_ppc64le
cp38-musllinux_s390x
Python 3.9 cp39-macosx_x86_64
cp39-macosx_universal2
cp39-macosx_arm64
cp39-win_amd64
cp39-win32
cp39-win_arm64
cp39-manylinux_x86_64
cp39-manylinux_i686
cp39-musllinux_x86_64
cp39-musllinux_i686
cp39-manylinux_aarch64
cp39-manylinux_ppc64le
cp39-manylinux_s390x
cp39-musllinux_aarch64
cp39-musllinux_ppc64le
cp39-musllinux_s390x
Python 3.10 cp310-macosx_x86_64
cp310-macosx_universal2
cp310-macosx_arm64
cp310-win_amd64
cp310-win32
cp310-win_arm64
cp310-manylinux_x86_64
cp310-manylinux_i686
cp310-musllinux_x86_64
cp310-musllinux_i686
cp310-manylinux_aarch64
cp310-manylinux_ppc64le
cp310-manylinux_s390x
cp310-musllinux_aarch64
cp310-musllinux_ppc64le
cp310-musllinux_s390x
Python 3.11 cp311-macosx_x86_64
cp311-macosx_universal2
cp311-macosx_arm64
cp311-win_amd64
cp311-win32
cp311-win_arm64
cp311-manylinux_x86_64
cp311-manylinux_i686
cp311-musllinux_x86_64
cp311-musllinux_i686
cp311-manylinux_aarch64
cp311-manylinux_ppc64le
cp311-manylinux_s390x
cp311-musllinux_aarch64
cp311-musllinux_ppc64le
cp311-musllinux_s390x
PyPy3.7 v7.3 pp37-macosx_x86_64 pp37-win_amd64 pp37-manylinux_x86_64
pp37-manylinux_i686
pp37-manylinux_aarch64
PyPy3.8 v7.3 pp38-macosx_x86_64 pp38-win_amd64 pp38-manylinux_x86_64
pp38-manylinux_i686
pp38-manylinux_aarch64
PyPy3.9 v7.3 pp39-macosx_x86_64 pp39-win_amd64 pp39-manylinux_x86_64
pp39-manylinux_i686
pp39-manylinux_aarch64

The list of supported and currently selected build identifiers can also be retrieved by passing the --print-build-identifiers flag to cibuildwheel. The format is python_tag-platform_tag, with tags similar to those in PEP 425.

For CPython, the minimally supported macOS version is 10.9; for PyPy 3.7, macOS 10.13 or higher is required.

Windows arm64 platform support is experimental.

See the cibuildwheel 1 documentation for past end of life versions of Python, and PyPy2.7.

Examples

Environment variables

# Only build on CPython 3.6
CIBW_BUILD: cp36-*

# Skip building on CPython 3.6 on the Mac
CIBW_SKIP: cp36-macosx_x86_64

# Skip building on CPython 3.8 on the Mac
CIBW_SKIP: cp38-macosx_x86_64

# Skip building on CPython 3.6 on all platforms
CIBW_SKIP: cp36-*

# Skip CPython 3.6 on Windows
CIBW_SKIP: cp36-win*

# Skip CPython 3.6 on 32-bit Windows
CIBW_SKIP: cp36-win32

# Skip CPython 3.6 and CPython 3.7
CIBW_SKIP: cp36-* cp37-*

# Skip Python 3.6 on Linux
CIBW_SKIP: cp36-manylinux*

# Skip 32-bit builds
CIBW_SKIP: "*-win32 *-manylinux_i686"

# Disable building PyPy wheels on all platforms
CIBW_SKIP: pp*

Separate multiple selectors with a space.

pyproject.toml

[tool.cibuildwheel]
# Only build on CPython 3.6
build = "cp36-*"

# Skip building on CPython 3.6 on the Mac
skip = "cp36-macosx_x86_64"

# Skip building on CPython 3.8 on the Mac
skip = "cp38-macosx_x86_64"

# Skip building on CPython 3.6 on all platforms
skip = "cp36-*"

# Skip CPython 3.6 on Windows
skip = "cp36-win*"

# Skip CPython 3.6 on 32-bit Windows
skip = "cp36-win32"

# Skip CPython 3.6 and CPython 3.7
skip = ["cp36-*", "cp37-*"]

# Skip Python 3.6 on Linux
skip = "cp36-manylinux*"

# Skip 32-bit builds
skip = ["*-win32", "*-manylinux_i686"]

# Disable building PyPy wheels on all platforms
skip = "pp*"

It is generally recommended to set CIBW_BUILD as an environment variable, though skip tends to be useful in a config file; you can statically declare that you don't support pypy, for example.

CIBW_ARCHS

Change the architectures built on your machine by default.

A list of architectures to build.

On macOS, this option can be used to cross-compile between x86_64, universal2 and arm64 for Apple Silicon support.

On Linux, this option can be used to build non-native architectures under emulation. See this guide for more information.

On Windows, this option can be used to compile for ARM64 from an Intel machine, provided the cross-compiling tools are installed.

Options:

  • Linux: x86_64 i686 aarch64 ppc64le s390x
  • macOS: x86_64 arm64 universal2
  • Windows: AMD64 x86 ARM64
  • auto: The default archs for your machine - see the table below.
    • auto64: Just the 64-bit auto archs
    • auto32: Just the 32-bit auto archs
  • native: the native arch of the build machine - Matches platform.machine().
  • all : expands to all the architectures supported on this OS. You may want to use CIBW_BUILD with this option to target specific architectures via build selectors.

Default: auto

Runner native auto auto64 auto32
Linux / Intel x86_64 x86_64 i686 x86_64 i686
Windows / Intel AMD64 AMD64 x86 AMD64 x86
Windows / ARM64 ARM64 ARM64 ARM64
macOS / Intel x86_64 x86_64 x86_64
macOS / AppleĀ Silicon arm64 arm64 arm64

If not listed above, auto is the same as native.

Platform-specific environment variables are also available:
CIBW_ARCHS_MACOS | CIBW_ARCHS_WINDOWS | CIBW_ARCHS_LINUX

This option can also be set using the command-line option --archs. This option cannot be set in an overrides section in pyproject.toml.

Examples

Environment variables

# Build `universal2` and `arm64` wheels on an Intel runner.
# Note that the `arm64` wheel and the `arm64` part of the `universal2`
# wheel cannot be tested in this configuration.
CIBW_ARCHS_MACOS: "x86_64 universal2 arm64"

# On an Linux Intel runner with qemu installed, build Intel and ARM wheels
CIBW_ARCHS_LINUX: "auto aarch64"

Separate multiple archs with a space.

pyproject.toml

# Build `universal2` and `arm64` wheels on an Intel runner.
# Note that the `arm64` wheel and the `arm64` part of the `universal2`
# wheel cannot be tested in this configuration.
[tool.cibuildwheel.macos]
archs = ["x86_64", "universal2", "arm64"]

# On an Linux Intel runner with qemu installed, build Intel and ARM wheels
[tool.cibuildwheel.linux]
archs = ["auto", "aarch64"]

It is generally recommended to use the environment variable or command-line option for Linux, as selecting archs often depends on your specific runner having qemu installed.

CIBW_PROJECT_REQUIRES_PYTHON

Manually set the Python compatibility of your project

By default, cibuildwheel reads your package's Python compatibility from pyproject.toml following the project metadata specification or from setup.cfg; finally it will try to inspect the AST of setup.py for a simple keyword assignment in a top level function call. If you need to override this behaviour for some reason, you can use this option.

When setting this option, the syntax is the same as project.requires-python, using 'version specifiers' like >=3.6, according to PEP440.

Default: reads your package's Python compatibility from pyproject.toml (project.requires-python) or setup.cfg (options.python_requires) or setup.py setup(python_requires="..."). If not found, cibuildwheel assumes the package is compatible with all versions of Python that it can build.

Note

Rather than using this environment variable, it's recommended you set this value statically in a way that your build backend can use it, too. This ensures that your package's metadata is correct when published on PyPI. This cibuildwheel-specific option is provided as an override, and therefore is only available in environment variable form.

  • If you have a pyproject.toml containing a [project] table, you can specify requires-python there.

    [project]
    ...
    requires-python = ">=3.6"

    Note that not all build backends fully support using a [project] table yet; specifically setuptools just added experimental support in version 61. Adding [project] to pyproject.toml requires all the other supported values to be specified there, or to be listed in dynamic.

  • If you're using setuptools, you can set this value in setup.cfg (preferred) or setup.py and cibuildwheel will read it from there.

Examples

Environment variables

CIBW_PROJECT_REQUIRES_PYTHON: ">=3.6"

CIBW_PRERELEASE_PYTHONS

Enable building with pre-release versions of Python if available

During the beta period, when new versions of Python are being tested, cibuildwheel will often gain early support for beta releases. If you would like to test wheel building with these versions, you can enable this flag.

Caution

This option is provided for testing purposes only. It is not recommended to distribute wheels built when CIBW_PRERELEASE_PYTHONS is set, such as uploading to PyPI. Please do not upload these wheels to PyPI, as they are not guaranteed to work with the final Python release. Once Python is ABI stable and enters the release candidate phase, that version of Python will become available without this flag.

Default: Off (0) if Python is available in beta phase. No effect otherwise.

This option can also be set using the command-line option --prerelease-pythons. This option is not available in the pyproject.toml config.

Examples

Environment variables

# Include latest Python beta
CIBW_PRERELEASE_PYTHONS: True

Build customization

CIBW_BUILD_FRONTEND

Set the tool to use to build, either "pip" (default for now) or "build"

Choose which build backend to use. Can either be "pip", which will run python -m pip wheel, or "build", which will run python -m build --wheel.

Tip

Until v2.0.0, pip was the only way to build wheels, and is still the default. However, we expect that at some point in the future, cibuildwheel will change the default to build, in line with the PyPA's recommendation. If you want to try build before this, you can use this option.

Examples

Environment variables

# Switch to using build
CIBW_BUILD_FRONTEND: "build"

# Ensure pip is used even if the default changes in the future
CIBW_BUILD_FRONTEND: "pip"

pyproject.toml

[tool.cibuildwheel]
# Switch to using build
build-frontend = "build"

# Ensure pip is used even if the default changes in the future
build-frontend = "pip"

CIBW_CONFIG_SETTINGS

Specify config-settings for the build backend.

Specify config settings for the build backend. Each space separated item will be passed via --config-setting. In TOML, you can specify a table of items, including arrays.

Tip

Currently, "build" supports arrays for options, but "pip" only supports single values.

Platform-specific environment variables also available:
CIBW_BEFORE_ALL_MACOS | CIBW_BEFORE_ALL_WINDOWS | CIBW_BEFORE_ALL_LINUX

Examples

Environment variables

CIBW_CONFIG_SETTINGS: "--build-option=--use-mypyc"

pyproject.toml

[tool.cibuildwheel.config-settings]
--build-option = "--use-mypyc"

CIBW_ENVIRONMENT

Set environment variables needed during the build

A list of environment variables to set during the build. Bash syntax should be used, even on Windows.

You must set this variable to pass variables to Linux builds (since they execute in a container). It also works for the other platforms.

You can use $PATH syntax to insert other variables, or the $(pwd) syntax to insert the output of other shell commands.

To specify more than one environment variable, separate the assignments by spaces.

Platform-specific environment variables are also available:
CIBW_ENVIRONMENT_MACOS | CIBW_ENVIRONMENT_WINDOWS | CIBW_ENVIRONMENT_LINUX

Examples

Environment variables

# Set some compiler flags
CIBW_ENVIRONMENT: CFLAGS='-g -Wall' CXXFLAGS='-Wall'

# Append a directory to the PATH variable (this is expanded in the build environment)
CIBW_ENVIRONMENT: PATH=$PATH:/usr/local/bin

# Prepend a directory containing spaces on Windows.
CIBW_ENVIRONMENT_WINDOWS: >
  PATH="C:\\Program Files\\PostgreSQL\\13\\bin;$PATH"

# Set BUILD_TIME to the output of the `date` command
CIBW_ENVIRONMENT: BUILD_TIME="$(date)"

# Supply options to `pip` to affect how it downloads dependencies
CIBW_ENVIRONMENT: PIP_EXTRA_INDEX_URL=https://pypi.myorg.com/simple

# Any pip command-line options can be set using the PIP_ prefix
# https://pip.pypa.io/en/stable/topics/configuration/#environment-variables
CIBW_ENVIRONMENT: PIP_GLOBAL_OPTION="build_ext -j4"

# Set two flags on linux only
CIBW_ENVIRONMENT_LINUX: BUILD_TIME="$(date)" SAMPLE_TEXT="sample text"

Separate multiple values with a space.

pyproject.toml

[tool.cibuildwheel]
# Set some compiler flags
environment = "CFLAGS='-g -Wall' CXXFLAGS='-Wall'"

# Set some compiler flags using a TOML table
environment = { CFLAGS="-g -Wall", CXXFLAGS="-Wall" }

# Append a directory to the PATH variable (this is expanded in the build environment)
environment = { PATH="$PATH:/usr/local/bin" }

# Prepend a directory containing spaces on Windows.
[tool.cibuildwheel.windows]
environment = { PATH='C:\\Program Files\\PostgreSQL\\13\\bin;$PATH' }

# Set BUILD_TIME to the output of the `date` command
environment = { BUILD_TIME="$(date)" }

# Supply options to `pip` to affect how it downloads dependencies
environment = { PIP_EXTRA_INDEX_URL="https://pypi.myorg.com/simple" }

# Any pip command-line option can be set using the PIP_ prefix
# https://pip.pypa.io/en/stable/topics/configuration/#environment-variables
environment = { PIP_GLOBAL_OPTION="build_ext -j4" }

# Set two flags on linux only
[tool.cibuildwheel.linux]
environment = { BUILD_TIME="$(date)", SAMPLE_TEXT="sample text" }

# Alternate form with out-of-line table for setting a few values
[tool.cibuildwheel.linux.environment]
BUILD_TIME = "$(date)"
SAMPLE_TEXT = "sample text"

In configuration mode, you can use a TOML table instead of a raw string as shown above.

Note

cibuildwheel always defines the environment variable CIBUILDWHEEL=1. This can be useful for building wheels with optional extensions.

CIBW_ENVIRONMENT_PASS_LINUX

Set environment variables on the host to pass-through to the container during the build.

A list of environment variables to pass into the linux container during the build. It has no affect on the other platforms, which can already access all environment variables directly.

To specify more than one environment variable, separate the variable names by spaces.

Examples

Environment passthrough

# Export a variable
CIBW_ENVIRONMENT_PASS_LINUX: CFLAGS

# Set two flags variables
CIBW_ENVIRONMENT_PASS_LINUX: BUILD_TIME SAMPLE_TEXT

Separate multiple values with a space.

pyproject.toml

[tool.cibuildwheel.linux]

# Export a variable
environment-pass = ["CFLAGS"]

# Set two flags variables
environment-pass = ["BUILD_TIME", "SAMPLE_TEXT"]

In configuration mode, you can use a TOML list instead of a raw string as shown above.

CIBW_BEFORE_ALL

Execute a shell command on the build system before any wheels are built.

Shell command that runs before any builds are run, to build or install parts that do not depend on the specific version of Python.

This option is very useful for the Linux build, where builds take place in isolated containers managed by cibuildwheel. This command will run inside the container before the wheel builds start. Note, if you're building both x86_64 and i686 wheels (the default), your build uses two different container images. In that case, this command will execute twice - once per build container.

The placeholder {package} can be used here; it will be replaced by the path to the package being built by cibuildwheel.

On Windows and macOS, the version of Python available inside CIBW_BEFORE_ALL is whatever is available on the host machine. On Linux, a modern Python version is available on PATH.

This option has special behavior in the overrides section in pyproject.toml. On linux, overriding it triggers a new container launch. It cannot be overridden on macOS and Windows.

Platform-specific environment variables also available:
CIBW_BEFORE_ALL_MACOS | CIBW_BEFORE_ALL_WINDOWS | CIBW_BEFORE_ALL_LINUX

Note

This command is executed in a different Python environment from the builds themselves. So you can't pip install a Python dependency in CIBW_BEFORE_ALL and use it in the build. Instead, look at CIBW_BEFORE_BUILD, or, if your project uses pyproject.toml, the build-system.requires field.

Examples

Environment variables

# Build third party library
CIBW_BEFORE_ALL: make -C third_party_lib

# Install system library
CIBW_BEFORE_ALL_LINUX: yum install -y libffi-devel

# Chain multiple commands using && and > in a YAML file, like:
CIBW_BEFORE_ALL: >
  yum install bzip2 -y &&
  make third_party

For multiline commands, see the last example. The character > means that whitespace is collapsed to a single line, and '&&' between each command ensures that errors are not ignored. Further reading on multiline YAML here..

pyproject.toml

# Build third party library
[tool.cibuildwheel]
before-all = "make -C third_party_lib"

# Install system library
[tool.cibuildwheel.linux]
before-all = "yum install -y libffi-devel"

# Run multiple commands using an array
before-all = [
  "yum install bzip2 -y",
  "make third_party",
]

In configuration files, you can use a TOML array, and each line will be run sequentially - joined with &&.

Note that manylinux_2_24 builds occur inside a Debian9 docker, where manylinux2010 and manylinux2014 builds occur inside a CentOS one. So for manylinux_2_24 the CIBW_BEFORE_ALL_LINUX command must use apt-get -y instead.

CIBW_BEFORE_BUILD

Execute a shell command preparing each wheel's build

A shell command to run before building the wheel. This option allows you to run a command in each Python environment before the pip wheel command. This is useful if you need to set up some dependency so it's available during the build.

If dependencies are required to build your wheel (for example if you include a header from a Python module), instead of using this command, we recommend adding requirements to a pyproject.toml file's build-system.requires array instead. This is reproducible, and users who do not get your wheels (such as Alpine or ClearLinux users) will still benefit.

The active Python binary can be accessed using python, and pip with pip; cibuildwheel makes sure the right version of Python and pip will be executed. The placeholder {package} can be used here; it will be replaced by the path to the package being built by cibuildwheel.

The command is run in a shell, so you can write things like cmd1 && cmd2.

Platform-specific environment variables are also available:
CIBW_BEFORE_BUILD_MACOS | CIBW_BEFORE_BUILD_WINDOWS | CIBW_BEFORE_BUILD_LINUX

Examples

Environment variables

# Install something required for the build (you might want to use pyproject.toml instead)
CIBW_BEFORE_BUILD: pip install pybind11

# Chain commands using &&
CIBW_BEFORE_BUILD_LINUX: python scripts/install-deps.py && make clean

# Run a script that's inside your project
CIBW_BEFORE_BUILD: bash scripts/prepare_for_build.sh

# If cibuildwheel is called with a package_dir argument, it's available as {package}
CIBW_BEFORE_BUILD: "{package}/script/prepare_for_build.sh"

pyproject.toml

[tool.cibuildwheel]

# Install something required for the build
# (you might want to use build-system.requires instead)
before-build = "pip install pybind11"

# Chain commands using && or make an array.
before-build = "python scripts/install-deps.py && make clean"
before-build = [
    "python scripts/install-deps.py",
    "make clean",
]

# Run a script that's inside your project
before-build = "bash scripts/prepare_for_build.sh"

# If cibuildwheel is called with a package_dir argument, it's available as {package}
before-build = "{package}/script/prepare_for_build.sh"

In configuration mode, you can use a array, and the items will be joined with &&. In TOML, using a single-quote string will avoid escapes - useful for Windows paths.

Note

If you need Python dependencies installed for the build, we recommend using pyproject.toml's build-system.requires instead. This is an example pyproject.toml file:

[build-system]
requires = [
    "setuptools>=42",
    "wheel",
    "Cython",
    "numpy==1.13.3; python_version<'3.5'",
    "oldest-supported-numpy; python_version>='3.5'",
]

build-backend = "setuptools.build_meta"

This PEP 517/PEP 518 style build allows you to completely control the build environment in cibuildwheel, PyPA-build, and pip, doesn't force downstream users to install anything they don't need, and lets you do more complex pinning (Cython, for example, requires a wheel to be built with an equal or earlier version of NumPy; pinning in this way is the only way to ensure your module works on all available NumPy versions).

CIBW_REPAIR_WHEEL_COMMAND

Execute a shell command to repair each built wheel

Default:

  • on Linux: 'auditwheel repair -w {dest_dir} {wheel}'
  • on macOS: 'delocate-wheel --require-archs {delocate_archs} -w {dest_dir} -v {wheel}'
  • on Windows: ''

A shell command to repair a built wheel by copying external library dependencies into the wheel tree and relinking them. The command is run on each built wheel (except for pure Python ones) before testing it.

The following placeholders must be used inside the command and will be replaced by cibuildwheel:

  • {wheel} for the absolute path to the built wheel
  • {dest_dir} for the absolute path of the directory where to create the repaired wheel
  • {delocate_archs} (macOS only) comma-separated list of architectures in the wheel.

The command is run in a shell, so you can run multiple commands like cmd1 && cmd2.

Platform-specific environment variables are also available:
CIBW_REPAIR_WHEEL_COMMAND_MACOS | CIBW_REPAIR_WHEEL_COMMAND_WINDOWS | CIBW_REPAIR_WHEEL_COMMAND_LINUX

Tip

cibuildwheel doesn't yet ship a default repair command for Windows.

If that's an issue for you, check out delvewheel - a new package that aims to do the same as auditwheel or delocate for Windows.

Because delvewheel is still relatively early-stage, cibuildwheel does not yet run it by default. However, we'd recommend giving it a try! See the examples below for usage.

Examples

Environment variables

# Use delvewheel on windows
CIBW_BEFORE_BUILD_WINDOWS: "pip install delvewheel"
CIBW_REPAIR_WHEEL_COMMAND_WINDOWS: "delvewheel repair -w {dest_dir} {wheel}"

# Don't repair macOS wheels
CIBW_REPAIR_WHEEL_COMMAND_MACOS: ""

# Pass the `--lib-sdir .` flag to auditwheel on Linux
CIBW_REPAIR_WHEEL_COMMAND_LINUX: "auditwheel repair --lib-sdir . -w {dest_dir} {wheel}"

# Multi-line example - use && to join on all platforms
CIBW_REPAIR_WHEEL_COMMAND: >
  python scripts/repair_wheel.py -w {dest_dir} {wheel} &&
  python scripts/check_repaired_wheel.py -w {dest_dir} {wheel}

pyproject.toml

# Use delvewheel on windows
[tool.cibuildwheel.windows]
before-build = "pip install delvewheel"
repair-wheel-command = "delvewheel repair -w {dest_dir} {wheel}"

# Don't repair macOS wheels
[tool.cibuildwheel.macos]
repair-wheel-command = ""

# Pass the `--lib-sdir .` flag to auditwheel on Linux
[tool.cibuildwheel.linux]
repair-wheel-command = "auditwheel repair --lib-sdir . -w {dest_dir} {wheel}"

# Multi-line example
[tool.cibuildwheel]
repair-wheel-command = [
  'python scripts/repair_wheel.py -w {dest_dir} {wheel}',
  'python scripts/check_repaired_wheel.py -w {dest_dir} {wheel}',
]

In configuration mode, you can use an inline array, and the items will be joined with &&.

CIBW_MANYLINUX_*_IMAGE, CIBW_MUSLLINUX_*_IMAGE

Specify alternative manylinux / musllinux container images

The available options are (default value):

Set an alternative Docker image to be used for building manylinux / musllinux wheels.

For CIBW_MANYLINUX_*_IMAGE, the value of this option can either be set to manylinux1, manylinux2010, manylinux2014, manylinux_2_24 or manylinux_2_28 to use a pinned version of the official manylinux images. Alternatively, set these options to any other valid Docker image name. For PyPy, the manylinux1 image is not available. For architectures other than x86 (x86_64 and i686) manylinux2014, manylinux_2_24 or manylinux_2_28 must be used, because the first version of the manylinux specification that supports additional architectures is manylinux2014. manylinux_2_28 is not supported for i686 architecture.

For CIBW_MUSLLINUX_*_IMAGE, the value of this option can either be set to musllinux_1_1 to use a pinned version of the official musllinux images. Alternatively, set these options to any other valid Docker image name.

If this option is blank, it will fall though to the next available definition (environment variable -> pyproject.toml -> default).

If setting a custom image, you'll need to make sure it can be used in the same way as the default images: all necessary Python and pip versions need to be present in /opt/python/, and the auditwheel tool needs to be present for cibuildwheel to work. Apart from that, the architecture and relevant shared system libraries need to be compatible to the relevant standard to produce valid manylinux1/manylinux2010/manylinux2014/manylinux_2_24/manylinux_2_28/musllinux_1_1 wheels (see pypa/manylinux on GitHub, PEP 513, PEP 571, PEP 599, PEP 600 and PEP 656 for more details).

Auditwheel detects the version of the manylinux / musllinux standard in the image through the AUDITWHEEL_PLAT environment variable, as cibuildwheel has no way of detecting the correct --plat command line argument to pass to auditwheel for a custom image. If a custom image does not correctly set this AUDITWHEEL_PLAT environment variable, the CIBW_ENVIRONMENT option can be used to do so (e.g., CIBW_ENVIRONMENT='AUDITWHEEL_PLAT="manylinux2010_$(uname -m)"').

Examples

Environment variables

# Build using the manylinux1 image to ensure manylinux1 wheels are produced
# Not setting PyPy to manylinux1, since there is no manylinux1 PyPy image.
CIBW_MANYLINUX_X86_64_IMAGE: manylinux1
CIBW_MANYLINUX_I686_IMAGE: manylinux1

# Build using the manylinux2014 image
CIBW_MANYLINUX_X86_64_IMAGE: manylinux2014
CIBW_MANYLINUX_I686_IMAGE: manylinux2014
CIBW_MANYLINUX_PYPY_X86_64_IMAGE: manylinux2014
CIBW_MANYLINUX_PYPY_I686_IMAGE: manylinux2014

# Build using the latest manylinux2014 release, instead of the cibuildwheel
# pinned version
CIBW_MANYLINUX_X86_64_IMAGE: quay.io/pypa/manylinux2014_x86_64:latest
CIBW_MANYLINUX_I686_IMAGE: quay.io/pypa/manylinux2014_i686:latest
CIBW_MANYLINUX_PYPY_X86_64_IMAGE: quay.io/pypa/manylinux2014_x86_64:latest
CIBW_MANYLINUX_PYPY_I686_IMAGE: quay.io/pypa/manylinux2014_i686:latest

# Build using a different image from the docker registry
CIBW_MANYLINUX_X86_64_IMAGE: dockcross/manylinux-x64
CIBW_MANYLINUX_I686_IMAGE: dockcross/manylinux-x86

pyproject.toml

[tool.cibuildwheel]
# Build using the manylinux1 image to ensure manylinux1 wheels are produced
# Not setting PyPy to manylinux1, since there is no manylinux1 PyPy image.
manylinux-x86_64-image = "manylinux1"
manylinux-i686-image = "manylinux1"

# Build using the manylinux2014 image
manylinux-x86_64-image = "manylinux2014"
manylinux-i686-image = "manylinux2014"
manylinux-pypy_x86_64-image = "manylinux2014"
manylinux-pypy_i686-image = "manylinux2014"

# Build using the latest manylinux2010 release, instead of the cibuildwheel
# pinned version
manylinux-x86_64-image = "quay.io/pypa/manylinux2010_x86_64:latest"
manylinux-i686-image = "quay.io/pypa/manylinux2010_i686:latest"
manylinux-pypy_x86_64-image = "quay.io/pypa/manylinux2010_x86_64:latest"
manylinux-pypy_i686-image = "quay.io/pypa/manylinux2010_i686:latest"

# Build using a different image from the docker registry
manylinux-x86_64-image = "dockcross/manylinux-x64"
manylinux-i686-image = "dockcross/manylinux-x86"

Like any other option, these can be placed in [tool.cibuildwheel.linux] if you prefer; they have no effect on macos and windows.

CIBW_CONTAINER_ENGINE

Specify which container engine to use when building Linux wheels

Options: docker podman

Default: docker

Set the container engine to use. Docker is the default, or you can switch to Podman. To use Docker, you need to have a Docker daemon running and docker available on PATH. To use Podman, it needs to be installed and podman available on PATH.

Tip

While most users will stick with Docker, Podman is available in different contexts - for example, it can be run inside a Docker container, or without root access. Thanks to the OCI, images are compatible between engines, so you can still use the regular manylinux/musllinux containers.

Examples

Environment variables

CIBW_CONTAINER_ENGINE: podman

pyproject.toml

[tool.cibuildwheel]
container-engine = "podman"

CIBW_DEPENDENCY_VERSIONS

Specify how cibuildwheel controls the versions of the tools it uses

Options: pinned latest <your constraints file>

Default: pinned

If CIBW_DEPENDENCY_VERSIONS is pinned, cibuildwheel uses versions of tools like pip, setuptools, virtualenv that were pinned with that release of cibuildwheel. This represents a known-good set of dependencies, and is recommended for build repeatability.

If set to latest, cibuildwheel will use the latest of these packages that are available on PyPI. This might be preferable if these packages have bug fixes that can't wait for a new cibuildwheel release.

To control the versions of dependencies yourself, you can supply a pip constraints file here and it will be used instead.

Note

If you need different dependencies for each python version, provide them in the same folder with a -pythonXY suffix. e.g. if your CIBW_DEPENDENCY_VERSIONS=./constraints.txt, cibuildwheel will use ./constraints-python37.txt on Python 3.7, or fallback to ./constraints.txt if that's not found.

Platform-specific environment variables are also available:
CIBW_DEPENDENCY_VERSIONS_MACOS | CIBW_DEPENDENCY_VERSIONS_WINDOWS

Note

This option does not affect the tools used on the Linux build - those versions are bundled with the manylinux/musllinux image that cibuildwheel uses. To change dependency versions on Linux, use the CIBW_MANYLINUX_ / CIBW_MUSLLINUX_ options.

Examples

Environment variables

# Use tools versions that are bundled with cibuildwheel (this is the default)
CIBW_DEPENDENCY_VERSIONS: pinned

# Use the latest versions available on PyPI
CIBW_DEPENDENCY_VERSIONS: latest

# Use your own pip constraints file
CIBW_DEPENDENCY_VERSIONS: ./constraints.txt

pyproject.toml

[tool.cibuildwheel]
# Use tools versions that are bundled with cibuildwheel (this is the default)
dependency-versions = "pinned"

# Use the latest versions available on PyPI
dependency-versions = "latest"

# Use your own pip constraints file
dependency-versions = "./constraints.txt"

Testing

CIBW_TEST_COMMAND

Execute a shell command to test each built wheel

Shell command to run tests after the build. The wheel will be installed automatically and available for import from the tests. To ensure the wheel is imported by your tests (instead of your source copy), tests are not run from your project directory. Use the placeholders {project} and {package} when specifying paths in your project. If this variable is not set, your wheel will not be installed after building.

  • {project} is an absolute path to the project root - the working directory where cibuildwheel was called.
  • {package} is the path to the package being built - the package_dir argument supplied to cibuildwheel on the command line.

The command is run in a shell, so you can write things like cmd1 && cmd2.

Platform-specific environment variables are also available:
CIBW_TEST_COMMAND_MACOS | CIBW_TEST_COMMAND_WINDOWS | CIBW_TEST_COMMAND_LINUX

Examples

Environment variables

# Run the project tests against the installed wheel using `nose`
CIBW_TEST_COMMAND: nosetests {project}/tests

# Run the package tests using `pytest`
CIBW_TEST_COMMAND: pytest {package}/tests

# Trigger an install of the package, but run nothing of note
CIBW_TEST_COMMAND: "echo Wheel installed"

# Multi-line example - join with && on all platforms
CIBW_TEST_COMMAND: >
  pytest {package}/tests &&
  python {package}/test.py

pyproject.toml

[tool.cibuildwheel]
# Run the project tests against the installed wheel using `nose`
test-command = "nosetests {project}/tests"

# Run the package tests using `pytest`
test-command = "pytest {package}/tests"

# Trigger an install of the package, but run nothing of note
test-command = "echo Wheel installed"

# Multiline example
test-command = [
  "pytest {package}/tests",
  "python {package}/test.py",
]

In configuration files, you can use an array, and the items will be joined with &&.

CIBW_BEFORE_TEST

Execute a shell command before testing each wheel

A shell command to run in each test virtual environment, before your wheel is installed and tested. This is useful if you need to install a non-pip package, invoke pip with different environment variables, or perform a multi-step pip installation (e.g. installing scikit-build or Cython before installing test package).

The active Python binary can be accessed using python, and pip with pip; cibuildwheel makes sure the right version of Python and pip will be executed. The placeholder {package} can be used here; it will be replaced by the path to the package being built by cibuildwheel.

The command is run in a shell, so you can write things like cmd1 && cmd2.

Platform-specific environment variables are also available:
CIBW_BEFORE_TEST_MACOS | CIBW_BEFORE_TEST_WINDOWS | CIBW_BEFORE_TEST_LINUX

Examples

Environment variables

# Install test dependencies with overwritten environment variables.
CIBW_BEFORE_TEST: CC=gcc CXX=g++ pip install -r requirements.txt

# Chain commands using &&
CIBW_BEFORE_TEST: rm -rf ./data/cache && mkdir -p ./data/cache

# Install non pip python package
CIBW_BEFORE_TEST: >
  cd some_dir &&
  ./configure &&
  make &&
  make install

# Install python packages that are required to install test dependencies
CIBW_BEFORE_TEST: pip install cmake scikit-build

pyproject.toml

[tool.cibuildwheel]
# Install test dependencies with overwritten environment variables.
before-test = "CC=gcc CXX=g++ pip install -r requirements.txt"

# Chain commands using && or using an array
before-test = "rm -rf ./data/cache && mkdir -p ./data/cache"
before-test = [
    "rm -rf ./data/cache",
    "mkdir -p ./data/cache",
]

# Install non pip python package
before-test = [
    "cd some_dir",
    "./configure",
    "make",
    "make install",
]

# Install python packages that are required to install test dependencies
[tool.cibuildwheel]
before-test = "pip install cmake scikit-build"

In configuration files, you can use an array, and the items will be joined with &&.

CIBW_TEST_REQUIRES

Install Python dependencies before running the tests

Space-separated list of dependencies required for running the tests.

Platform-specific environment variables are also available:
CIBW_TEST_REQUIRES_MACOS | CIBW_TEST_REQUIRES_WINDOWS | CIBW_TEST_REQUIRES_LINUX

Examples

Environment variables

# Install pytest before running CIBW_TEST_COMMAND
CIBW_TEST_REQUIRES: pytest

# Install specific versions of test dependencies
CIBW_TEST_REQUIRES: nose==1.3.7 moto==0.4.31

pyproject.toml

# Install pytest before running CIBW_TEST_COMMAND
[tool.cibuildwheel]
test-requires = "pytest"

# Install specific versions of test dependencies
[tool.cibuildwheel]
test-requires = ["nose==1.3.7", "moto==0.4.31"]

In configuration files, you can use an array, and the items will be joined with a space.

CIBW_TEST_EXTRAS

Install your wheel for testing using extras_require

List of extras_require options that should be included when installing the wheel prior to running the tests. This can be used to avoid having to redefine test dependencies in CIBW_TEST_REQUIRES if they are already defined in setup.py or setup.cfg.

Platform-specific environment variables are also available:
CIBW_TEST_EXTRAS_MACOS | CIBW_TEST_EXTRAS_WINDOWS | CIBW_TEST_EXTRAS_LINUX

Examples

Environment variables

# Will cause the wheel to be installed with `pip install <wheel_file>[test,qt]`
CIBW_TEST_EXTRAS: "test,qt"

Separate multiple items with a comma.

pyproject.toml

[tool.cibuildwheel]
# Will cause the wheel to be installed with `pip install <wheel_file>[test,qt]`
test-extras = ["test", "qt"]

In configuration files, you can use an inline array, and the items will be joined with a comma.

CIBW_TEST_SKIP

Skip running tests on some builds

This will skip testing on any identifiers that match the given skip patterns (see CIBW_SKIP). This can be used to mask out tests for wheels that have missing dependencies upstream that are slow or hard to build, or to skip slow tests on emulated architectures.

With macOS universal2 wheels, you can also skip the individual archs inside the wheel using an :arch suffix. For example, cp39-macosx_universal2:x86_64 or cp39-macosx_universal2:arm64.

This option is not supported in the overrides section in pyproject.toml.

Examples

Environment variables

# Will avoid testing on emulated architectures
CIBW_TEST_SKIP: "*-*linux_{aarch64,ppc64le,s390x}"

# Skip trying to test arm64 builds on Intel Macs
CIBW_TEST_SKIP: "*-macosx_arm64 *-macosx_universal2:arm64"

pyproject.toml

[tool.cibuildwheel]
# Will avoid testing on emulated architectures
test-skip = "*-*linux_{aarch64,ppc64le,s390x}"

# Skip trying to test arm64 builds on Intel Macs
test-skip = "*-macosx_arm64 *-macosx_universal2:arm64"

Other

CIBW_BUILD_VERBOSITY

Increase/decrease the output of pip wheel

An number from 1 to 3 to increase the level of verbosity (corresponding to invoking pip with -v, -vv, and -vvv), between -1 and -3 (-q, -qq, and -qqq), or just 0 (default verbosity). These flags are useful while debugging a build when the output of the actual build invoked by pip wheel is required.

Platform-specific environment variables are also available:
CIBW_BUILD_VERBOSITY_MACOS | CIBW_BUILD_VERBOSITY_WINDOWS | CIBW_BUILD_VERBOSITY_LINUX

Examples

Environment variables

# Increase pip debugging output
CIBW_BUILD_VERBOSITY: 1

pyproject.toml

[tool.cibuildwheel]
# Increase pip debugging output
build-verbosity = 1

Command line options

usage: cibuildwheel [-h] [--platform {auto,linux,macos,windows}]
                    [--archs ARCHS] [--only ONLY] [--output-dir OUTPUT_DIR]
                    [--config-file CONFIG_FILE] [--print-build-identifiers]
                    [--allow-empty] [--prerelease-pythons]
                    [PACKAGE]

Build wheels for all the platforms.

positional arguments:
  PACKAGE               Path to the package that you want wheels for. Default:
                        the working directory. Can be a directory inside the
                        working directory, or an sdist. When set to a
                        directory, the working directory is still considered
                        the 'project' and is copied into the build container
                        on Linux. When set to a tar.gz sdist file, --config-
                        file and --output-dir are relative to the current
                        directory, and other paths are relative to the
                        expanded SDist directory.

optional arguments:
  -h, --help            show this help message and exit
  --platform {auto,linux,macos,windows}
                        Platform to build for. Use this option to override the
                        auto-detected platform or to run cibuildwheel on your
                        development machine. Specifying "macos" or "windows"
                        only works on that operating system, but "linux" works
                        on all three, as long as Docker/Podman is installed.
                        Default: auto.
  --archs ARCHS         Comma-separated list of CPU architectures to build
                        for. When set to 'auto', builds the architectures
                        natively supported on this machine. Set this option to
                        build an architecture via emulation, for example,
                        using binfmt_misc and QEMU. Default: auto. Choices:
                        auto, auto64, auto32, native, all, x86_64, i686,
                        aarch64, ppc64le, s390x, universal2, arm64, x86,
                        AMD64, ARM64
  --only ONLY           Force a single wheel build when given an identifier.
                        Overrides CIBW_BUILD/CIBW_SKIP. --platform and --arch
                        cannot be specified if this is given.
  --output-dir OUTPUT_DIR
                        Destination folder for the wheels. Default:
                        wheelhouse.
  --config-file CONFIG_FILE
                        TOML config file. Default: "", meaning
                        {package}/pyproject.toml, if it exists. To refer to a
                        project inside your project, use {package}; this
                        matters if you build from an SDist.
  --print-build-identifiers
                        Print the build identifiers matched by the current
                        invocation and exit.
  --allow-empty         Do not report an error code if the build does not
                        match any wheels.
  --prerelease-pythons  Enable pre-release Python versions if available.

Most options are supplied via environment variables or in --config-file
(pyproject.toml usually). See https://github.com/pypa/cibuildwheel#options for
info.

Placeholders

Some options support placeholders, like {project}, {package} or {wheel}, that are substituted by cibuildwheel before they are used. If, for some reason, you need to write the literal name of a placeholder, e.g. literally {project} in a command that would ordinarily substitute {project}, prefix it with a hash character - #{project}. This is only necessary in commands where the specific string between the curly brackets would be substituted - otherwise, strings not modified.