Bump version: v2.18.1

Update dependencies

Co-authored-by: cibuildwheel-bot[bot] <83877280+cibuildwheel-bot[bot]@users.noreply.github.com>

.circleci/prepare.sh

@@ -4,7 +4,9 @@ set -o xtrace
 
 $PYTHON --version
 $PYTHON -m pip --version
-$PYTHON -m virtualenv -p "$PYTHON" venv
+$PYTHON -m virtualenv --version
+$PYTHON -m virtualenv --no-setuptools --no-wheel -p "$PYTHON" venv
+venv/bin/python -m pip install -U pip
 venv/bin/python -m pip install -e ".[dev]"
 venv/bin/python -m pip freeze
 venv/bin/python --version

.github/matchers/pylint.json

@@ -1,32 +0,0 @@
-{
-  "problemMatcher": [
-    {
-      "severity": "warning",
-      "pattern": [
-        {
-          "regexp": "^([^:]+):(\\d+):(\\d+): ([A-DF-Z]\\d+): \\033\\[[\\d;]+m([^\\033]+).*$",
-          "file": 1,
-          "line": 2,
-          "column": 3,
-          "code": 4,
-          "message": 5
-        }
-      ],
-      "owner": "pylint-warning"
-    },
-    {
-      "severity": "error",
-      "pattern": [
-        {
-          "regexp": "^([^:]+):(\\d+):(\\d+): (E\\d+): \\033\\[[\\d;]+m([^\\033]+).*$",
-          "file": 1,
-          "line": 2,
-          "column": 3,
-          "code": 4,
-          "message": 5
-        }
-      ],
-      "owner": "pylint-error"
-    }
-  ]
-}

.github/workflows/test.yml

@@ -28,9 +28,7 @@ jobs:
     - name: Check manifest
       run: pipx run nox -s check_manifest
     - name: PyLint checks
-      run: |
-        echo "::add-matcher::$GITHUB_WORKSPACE/.github/matchers/pylint.json"
-        pipx run nox -s pylint
+      run: pipx run nox -s pylint -- --output-format=github
 
   test:
     name: Test cibuildwheel on ${{ matrix.os }} (${{ matrix.python_version }})

.pre-commit-config.yaml

@@ -14,18 +14,12 @@ repos:
   - id: trailing-whitespace
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.4.3
+  rev: v0.4.4
   hooks:
   - id: ruff
     args: ["--fix", "--show-fixes"]
   - id: ruff-format
 
-- repo: https://github.com/asottile/setup-cfg-fmt
-  rev: v2.5.0
-  hooks:
-  - id: setup-cfg-fmt
-    args: [--include-version-classifiers, --min-py-version=3.8, --max-py-version=3.12]
-
 - repo: https://github.com/pre-commit/mirrors-mypy
   rev: v1.10.0
   hooks:
@@ -82,7 +76,7 @@ repos:
 
 
 - repo: https://github.com/python-jsonschema/check-jsonschema
-  rev: 0.28.2
+  rev: 0.28.3
   hooks:
     - id: check-dependabot
     - id: check-github-actions

.readthedocs.yml

@@ -11,5 +11,5 @@ build:
     - asdf install uv latest
     - asdf global uv latest
     - uv venv
-    - uv pip install .[docs]
-    - .venv/bin/python -m mkdocs build --site-dir $READTHEDOCS_OUTPUT/html
+    - uv pip install -e.[docs]
+    - NO_COLOR=1 .venv/bin/mkdocs build --strict --site-dir $READTHEDOCS_OUTPUT/html

MANIFEST.in

@@ -1,6 +0,0 @@
-recursive-include cibuildwheel *.cfg
-recursive-include cibuildwheel *.in
-recursive-include cibuildwheel *.py
-recursive-include cibuildwheel *.toml
-recursive-include cibuildwheel *.txt
-recursive-include cibuildwheel *.typed

README.md

@@ -93,7 +93,7 @@ jobs:
       - uses: actions/setup-python@v5
 
       - name: Install cibuildwheel
-        run: python -m pip install cibuildwheel==2.18.0
+        run: python -m pip install cibuildwheel==2.18.1
 
       - name: Build wheels
         run: python -m cibuildwheel --output-dir wheelhouse
@@ -165,19 +165,19 @@ Here are some repos that use cibuildwheel.
 | [NCNN][]                          | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | ncnn is a high-performance neural network inference framework optimized for the mobile platform |
 | [Prophet][]                       | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Tool for producing high quality forecasts for time series data that has multiple seasonality with linear or non-linear growth. |
 | [MyPy][]                          | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | The compiled version of MyPy using MyPyC. |
-| [Kivy][]                          | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Open source UI framework written in Python, running on Windows, Linux, macOS, Android and iOS |
 | [duckdb][]                        | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | DuckDB is an in-process SQL OLAP Database Management System |
+| [Kivy][]                          | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Open source UI framework written in Python, running on Windows, Linux, macOS, Android and iOS |
 
 [scikit-learn]: https://github.com/scikit-learn/scikit-learn
-[pytorch-fairseq]: https://github.com/pytorch/fairseq
+[pytorch-fairseq]: https://github.com/facebookresearch/fairseq
 [NumPy]: https://github.com/numpy/numpy
 [Tornado]: https://github.com/tornadoweb/tornado
 [Matplotlib]: https://github.com/matplotlib/matplotlib
 [NCNN]: https://github.com/Tencent/ncnn
 [Prophet]: https://github.com/facebook/prophet
 [MyPy]: https://github.com/mypyc/mypy_mypyc-wheels
-[Kivy]: https://github.com/kivy/kivy
 [duckdb]: https://github.com/duckdb/duckdb
+[Kivy]: https://github.com/kivy/kivy
 
 [appveyor icon]: docs/data/readme_icons/appveyor.svg
 [github icon]: docs/data/readme_icons/github.svg
@@ -210,14 +210,27 @@ Changelog
 
 <!-- this section was generated by bin/update_readme_changelog.py -- do not edit manually -->
 
+### v2.18.1
+
+- 🌟 Add free-threaded Linux and Windows builds for 3.13. New identifiers `cp313t-*`, new option `CIBW_FREE_THREADED_SUPPORT`/`tool.cibuildwheel.free-threaded-support` required to opt-in. [See the docs](https://cibuildwheel.pypa.io/en/stable/options/#free-threaded-support) for more information. (#1831)
+- ✨ The `container-engine` is now a build (non-global) option. (#1792)
+- 🛠 The build backend for cibuildwheel is now hatchling. (#1297)
+- 🛠 Significant improvements and modernization to our noxfile. (#1823)
+- 🛠 Use pylint's new GitHub Actions reporter instead of a custom matcher. (#1823)
+- 🛠 Unpin virtualenv updates for Python 3.7+ (#1830)
+- 🐛 Fix running linux tests from Windows or macOS ARM. (#1788)
+- 📚 Fix our documentation build. (#1821)
+
+
 ### v2.18.0
 
 _12 May 2024_
 
-- ✨ Adds CPython 3.13 support, under the prerelease flag [CIBW_PRERELEASE_PYTHONS](https://cibuildwheel.pypa.io/en/stable/options/#prerelease-pythons). This version of cibuildwheel uses 3.13.0b1. Free-threading mode is not available yet, waiting on official binaries (planned for beta 2) and pip support.
+- ✨ Adds CPython 3.13 support, under the prerelease flag [CIBW_PRERELEASE_PYTHONS](https://cibuildwheel.pypa.io/en/stable/options/#prerelease-pythons). This version of cibuildwheel uses 3.13.0b1. Free-threading mode is not available yet (#1657), waiting on official binaries (planned for beta 2) and pip support.
 
-    While CPython is in beta, the ABI can change, so your wheels might not be compatible with the final release. For this reason, we don't recommend distributing wheels until RC1, at which point 3.13 will be available in cibuildwheel without the flag. (#1816)
-- ✨ Musllinux now defaults to `musllinux_1_2`. You can set the older `manylinux_1_1` via config if needed. (#1817)
+    _While CPython is in beta, the ABI can change, so your wheels might not be compatible with the final release. For this reason, we don't recommend distributing wheels until RC1, at which point 3.13 will be available in cibuildwheel without the flag._ (#1815)
+
+- ✨ Musllinux now defaults to `musllinux_1_2`. You can set the older `musllinux_1_1` via config if needed. (#1817)
 - 🛠 No longer pre-seed setuptools/wheel in virtual environments (#1819)
 - 🛠 Respect the constraints file when building with pip, matching build (#1818)
 - 🛠 Use uv to compile our pinned dependencies, 10x faster and doesn't require special setup (#1778)
@@ -232,14 +245,14 @@ _12 May 2024_
 _11 March 2024_
 
 - 🌟 Adds the ability to inherit configuration in TOML overrides. This makes certain configurations much simpler. If you're overriding an option like `before-build` or `environment`, and you just want to add an  extra command or environment variable, you can just append (or prepend) to the previous config. See [the docs](https://cibuildwheel.pypa.io/en/stable/options/#inherit) for more information. (#1730)
-- 🌟 Adds official support for native arm64 macOS GitHub runners. To use them, just specify `macos-14` as an `os` of your job in your workflow file. You can also keep `macos-13` in your build matrix to build x86_64. Check out the new [GitHub Actions example config](https://cibuildwheel.pypa.io/en/stable/setup/#github-actions).
+- 🌟 Adds official support for native `arm64` macOS GitHub runners. To use them, just specify `macos-14` as an `os` of your job in your workflow file. You can also keep `macos-13` in your build matrix to build `x86_64`. Check out the new [GitHub Actions example config](https://cibuildwheel.pypa.io/en/stable/setup/#github-actions).
 - ✨ You no longer need to specify `--platform` to run cibuildwheel locally! Instead it will detect your platform automatically. This was a safety feature, no longer necessary. (#1727)
 - 🛠 Removed setuptools and wheel pinned versions. This only affects old-style projects without a `pyproject.toml`, projects with `pyproject.toml` are already getting fresh versions of their `build-system.requires` installed into an isolated environment. (#1725)
 - 🛠 Improve how the GitHub Action passes arguments (#1757)
 - 🛠 Remove a system-wide install of pipx in the GitHub Action (#1745)
-- 🐛 No longer will cibuildwheel override the PIP_CONSTRAINT environment variable when using the `build` frontend. Instead it will be extended. (#1675)
-- 🐛 Fix a bug where building and testing both x86_86 and arm64 wheels on the same runner caused the wrong architectures in the test environment (#1750)
-- 🐛 Fix a bug that prevented testing a CPython 3.8 wheel targeting macOS 11+ on x86_64 (#1768)
+- 🐛 No longer will cibuildwheel override the `PIP_CONSTRAINT` environment variable when using the `build` frontend. Instead it will be extended. (#1675)
+- 🐛 Fix a bug where building and testing both `x86_86` and `arm64` wheels on the same runner caused the wrong architectures in the test environment (#1750)
+- 🐛 Fix a bug that prevented testing a CPython 3.8 wheel targeting macOS 11+ on `x86_64` (#1768)
 - 📚 Moved the docs onto the official PyPA domain - they're now available at https://cibuildwheel.pypa.io . (#1775)
 - 📚 Docs and examples improvements (#1762, #1734)
 
@@ -257,14 +270,6 @@ _28 January 2024_
 
 - 🛠 Update manylinux pins to upgrade from a problematic PyPy version. (#1737)
 
-### v2.16.3
-
-_26 January 2024_
-
-- 🐛 Fix a bug when building from sdist, where relative paths to files in the package didn't work because the working directory was wrong (#1687)
-- 🛠 Adds the ability to disable mounting the host filesystem in containers to `/host`, through the `disable_host_mount` suboption on [`CIBW_CONTAINER_ENGINE`](https://cibuildwheel.pypa.io/en/stable/options/#container-engine).
-- 📚 A lot of docs improvements! (#1708, #1705, #1686, #1679, #1667, #1665)
-
 <!-- END bin/update_readme_changelog.py -->
 
 ---

bin/bump_version.py

@@ -1,13 +1,12 @@
 #!/usr/bin/env python3
 
 # /// script
-# dependencies = ["click", "packaging"]
+# dependencies = ["click", "packaging", "tomli; python_version<'3.11'"]
 # ///
 
 
 from __future__ import annotations
 
-import configparser
 import glob
 import os
 import subprocess
@@ -18,8 +17,14 @@ from pathlib import Path
 import click
 from packaging.version import InvalidVersion, Version
 
+if sys.version_info < (3, 11):
+    import tomli as tomllib
+else:
+    import tomllib
+
 config = [
     # file path, version find/replace format
+    ("pyproject.toml", 'version = "{}"'),
     ("README.md", "cibuildwheel=={}"),
     ("cibuildwheel/__init__.py", '__version__ = "{}"'),
     ("docs/faq.md", "cibuildwheel=={}"),
@@ -27,7 +32,6 @@ config = [
     ("docs/setup.md", "cibuildwheel=={}"),
     ("examples/*", "cibuildwheel=={}"),
     ("examples/*", "cibuildwheel@v{}"),
-    ("setup.cfg", "version = {}"),
 ]
 
 RED = "\u001b[31m"
@@ -37,10 +41,8 @@ OFF = "\u001b[0m"
 
 @click.command()
 def bump_version() -> None:
-    # Update if moving setup.cfg to pyproject.toml
-    cfg = configparser.ConfigParser()
-    cfg.read("setup.cfg")
-    current_version = cfg["metadata"]["version"]
+    with open("pyproject.toml", "rb") as f:
+        current_version = tomllib.load(f)["project"]["version"]
 
     try:
         commit_date_str = subprocess.run(

bin/generate_schema.py

@@ -1,5 +1,9 @@
 #!/usr/bin/env python
 
+# /// script
+# dependencies = ["pyyaml"]
+# ///
+
 import argparse
 import copy
 import json
@@ -100,6 +104,10 @@ properties:
     description: Set environment variables on the host to pass-through to the container
       during the build.
     type: string_array
+  free-threaded-support:
+    type: boolean
+    default: false
+    description: The project supports free-threaded builds of Python (PEP703)
   manylinux-aarch64-image:
     type: string
     description: Specify alternative manylinux / musllinux container images
@@ -243,8 +251,8 @@ for key, value in schema["properties"].items():
 non_global_options = {k: {"$ref": f"#/properties/{k}"} for k in schema["properties"]}
 del non_global_options["build"]
 del non_global_options["skip"]
-del non_global_options["container-engine"]
 del non_global_options["test-skip"]
+del non_global_options["free-threaded-support"]
 
 overrides["items"]["properties"]["select"]["oneOf"] = string_array
 overrides["items"]["properties"] |= non_global_options.copy()
@@ -254,6 +262,7 @@ del overrides["items"]["properties"]["archs"]
 not_linux = non_global_options.copy()
 
 del not_linux["environment-pass"]
+del not_linux["container-engine"]
 for key in list(not_linux):
     if "linux-" in key:
         del not_linux[key]

bin/projects.py

@@ -1,5 +1,13 @@
 #!/usr/bin/env python3
 
+# /// script
+# dependencies = [
+#   "click",
+#   "pyyaml",
+#   "pygithub",
+# ]
+# ///
+
 """
 Convert a yaml project list into a nice table.
 

bin/update_pythons.py

@@ -58,7 +58,7 @@ AnyConfig = Union[ConfigWinCP, ConfigWinPP, ConfigMacOS]
 
 
 class WindowsVersions:
-    def __init__(self, arch_str: ArchStr) -> None:
+    def __init__(self, arch_str: ArchStr, free_threaded: bool) -> None:
         response = requests.get("https://api.nuget.org/v3/index.json")
         response.raise_for_status()
         api_info = response.json()
@@ -72,7 +72,11 @@ class WindowsVersions:
 
         self.arch_str = arch_str
         self.arch = ARCH_DICT[arch_str]
+        self.free_threaded = free_threaded
+
         package = PACKAGE_DICT[arch_str]
+        if free_threaded:
+            package = f"{package}-freethreaded"
 
         response = requests.get(f"{endpoint}{package}/index.json")
         response.raise_for_status()
@@ -92,8 +96,9 @@ class WindowsVersions:
         if not versions:
             return None
 
+        flags = "t" if self.free_threaded else ""
         version = versions[0]
-        identifier = f"cp{version.major}{version.minor}-{self.arch}"
+        identifier = f"cp{version.major}{version.minor}{flags}-{self.arch}"
         return ConfigWinCP(
             identifier=identifier,
             version=self.version_dict[version],
@@ -233,9 +238,12 @@ class CPythonVersions:
 
 class AllVersions:
     def __init__(self) -> None:
-        self.windows_32 = WindowsVersions("32")
-        self.windows_64 = WindowsVersions("64")
-        self.windows_arm64 = WindowsVersions("ARM64")
+        self.windows_32 = WindowsVersions("32", False)
+        self.windows_t_32 = WindowsVersions("32", True)
+        self.windows_64 = WindowsVersions("64", False)
+        self.windows_t_64 = WindowsVersions("64", True)
+        self.windows_arm64 = WindowsVersions("ARM64", False)
+        self.windows_t_arm64 = WindowsVersions("ARM64", True)
         self.windows_pypy_64 = PyPyVersions("64")
 
         self.macos_cpython = CPythonVersions()
@@ -259,14 +267,19 @@ class AllVersions:
                     config_update = self.macos_pypy.update_version_macos(spec)
                 elif "macosx_arm64" in identifier:
                     config_update = self.macos_pypy_arm64.update_version_macos(spec)
-        elif "win32" in identifier:
-            if identifier.startswith("cp"):
-                config_update = self.windows_32.update_version_windows(spec)
+        elif "t-win32" in identifier and identifier.startswith("cp"):
+            config_update = self.windows_t_32.update_version_windows(spec)
+        elif "win32" in identifier and identifier.startswith("cp"):
+            config_update = self.windows_32.update_version_windows(spec)
+        elif "t-win_amd64" in identifier and identifier.startswith("cp"):
+            config_update = self.windows_t_64.update_version_windows(spec)
         elif "win_amd64" in identifier:
             if identifier.startswith("cp"):
                 config_update = self.windows_64.update_version_windows(spec)
             elif identifier.startswith("pp"):
                 config_update = self.windows_pypy_64.update_version_windows(spec)
+        elif "t-win_arm64" in identifier and identifier.startswith("cp"):
+            config_update = self.windows_t_arm64.update_version_windows(spec)
         elif "win_arm64" in identifier and identifier.startswith("cp"):
             config_update = self.windows_arm64.update_version_windows(spec)
 

bin/update_virtualenv.py

@@ -53,10 +53,6 @@ def git_ls_remote_versions(url) -> list[VersionTuple]:
             if version.is_prerelease:
                 log.info("Ignoring pre-release %r", str(version))
                 continue
-            # Do not upgrade past 20.22.0 to keep python 3.6 compat
-            if version >= Version("20.22.0"):
-                log.info("Ignoring %r which is not compatible with python 3.6", str(version))
-                continue
             versions.append(VersionTuple(version, version_string))
         except InvalidVersion:
             log.warning("Ignoring ref %r", ref)
@@ -82,15 +78,20 @@ def update_virtualenv(force: bool, level: str) -> None:
 
     original_toml = toml_file_path.read_text()
     with toml_file_path.open("rb") as f:
-        loaded_file = tomllib.load(f)
-    version = str(loaded_file["version"])
+        configurations = tomllib.load(f)
+    default = configurations.pop("default")
+    version = str(default["version"])
     versions = git_ls_remote_versions(GET_VIRTUALENV_GITHUB)
     if versions[0].version > Version(version):
         version = versions[0].version_string
 
-    result_toml = (
-        f'version = "{version}"\n'
-        f'url = "{GET_VIRTUALENV_URL_TEMPLATE.format(version=version)}"\n'
+    configurations["default"] = {
+        "version": version,
+        "url": GET_VIRTUALENV_URL_TEMPLATE.format(version=version),
+    }
+    result_toml = "".join(
+        f'{key} = {{ version = "{value["version"]}", url = "{value["url"]}" }}\n'
+        for key, value in configurations.items()
     )
 
     rich.print()  # spacer

cibuildwheel/__init__.py

@@ -1,3 +1,3 @@
 from __future__ import annotations
 
-__version__ = "2.18.0"
+__version__ = "2.18.1"

cibuildwheel/linux.py

@@ -11,8 +11,8 @@ from typing import OrderedDict, Tuple
 from ._compat.typing import assert_never
 from .architecture import Architecture
 from .logger import log
-from .oci_container import OCIContainer
-from .options import Options
+from .oci_container import OCIContainer, OCIContainerEngineConfig
+from .options import BuildOptions, Options
 from .typing import PathOrStr
 from .util import (
     AlreadyBuiltWheelError,
@@ -44,6 +44,7 @@ class PythonConfiguration:
 class BuildStep:
     platform_configs: list[PythonConfiguration]
     platform_tag: str
+    container_engine: OCIContainerEngineConfig
     container_image: str
 
 
@@ -65,8 +66,9 @@ def get_python_configurations(
     ]
 
 
-def container_image_for_python_configuration(config: PythonConfiguration, options: Options) -> str:
-    build_options = options.build_options(config.identifier)
+def container_image_for_python_configuration(
+    config: PythonConfiguration, build_options: BuildOptions
+) -> str:
     # e.g
     # identifier is 'cp310-manylinux_x86_64'
     # platform_tag is 'manylinux_x86_64'
@@ -91,15 +93,18 @@ def get_build_steps(
     Groups PythonConfigurations into BuildSteps. Each BuildStep represents a
     separate container instance.
     """
-    steps = OrderedDict[Tuple[str, str, str], BuildStep]()
+    steps = OrderedDict[Tuple[str, str, str, OCIContainerEngineConfig], BuildStep]()
 
     for config in python_configurations:
         _, platform_tag = config.identifier.split("-", 1)
 
-        before_all = options.build_options(config.identifier).before_all
-        container_image = container_image_for_python_configuration(config, options)
+        build_options = options.build_options(config.identifier)
 
-        step_key = (platform_tag, container_image, before_all)
+        before_all = build_options.before_all
+        container_image = container_image_for_python_configuration(config, build_options)
+        container_engine = build_options.container_engine
+
+        step_key = (platform_tag, container_image, before_all, container_engine)
 
         if step_key in steps:
             steps[step_key].platform_configs.append(config)
@@ -107,6 +112,7 @@ def get_build_steps(
             steps[step_key] = BuildStep(
                 platform_configs=[config],
                 platform_tag=platform_tag,
+                container_engine=container_engine,
                 container_image=container_image,
             )
 
@@ -331,6 +337,10 @@ def build_in_container(
             virtualenv_env = env.copy()
             virtualenv_env["PATH"] = f"{venv_dir / 'bin'}:{virtualenv_env['PATH']}"
 
+            # TODO remove me once virtualenv provides pip>=24.1b1
+            if config.version == "3.13":
+                container.call(["pip", "install", "pip>=24.1b1"], env=virtualenv_env)
+
             if build_options.before_test:
                 before_test_prepared = prepare_command(
                     build_options.before_test,
@@ -388,29 +398,6 @@ def build_in_container(
 
 
 def build(options: Options, tmp_path: Path) -> None:  # noqa: ARG001
-    try:
-        # check the container engine is installed
-        subprocess.run(
-            [options.globals.container_engine.name, "--version"],
-            check=True,
-            stdout=subprocess.DEVNULL,
-        )
-    except subprocess.CalledProcessError:
-        print(
-            unwrap(
-                f"""
-                cibuildwheel: {options.globals.container_engine} not found. An
-                OCI exe like Docker or Podman is required to run Linux builds.
-                If you're building on Travis CI, add `services: [docker]` to
-                your .travis.yml. If you're building on Circle CI in Linux,
-                add a `setup_remote_docker` step to your .circleci/config.yml.
-                If you're building on Cirrus CI, use `docker_builder` task.
-                """
-            ),
-            file=sys.stderr,
-        )
-        sys.exit(2)
-
     python_configurations = get_python_configurations(
         options.globals.build_selector, options.globals.architectures
     )
@@ -425,6 +412,29 @@ def build(options: Options, tmp_path: Path) -> None:  # noqa: ARG001
     container_package_dir = container_project_path / abs_package_dir.relative_to(cwd)
 
     for build_step in get_build_steps(options, python_configurations):
+        try:
+            # check the container engine is installed
+            subprocess.run(
+                [build_step.container_engine.name, "--version"],
+                check=True,
+                stdout=subprocess.DEVNULL,
+            )
+        except subprocess.CalledProcessError:
+            print(
+                unwrap(
+                    f"""
+                    cibuildwheel: {build_step.container_engine.name} not found. An
+                    OCI exe like Docker or Podman is required to run Linux builds.
+                    If you're building on Travis CI, add `services: [docker]` to
+                    your .travis.yml. If you're building on Circle CI in Linux,
+                    add a `setup_remote_docker` step to your .circleci/config.yml.
+                    If you're building on Cirrus CI, use `docker_builder` task.
+                    """
+                ),
+                file=sys.stderr,
+            )
+            sys.exit(2)
+
         try:
             ids_to_build = [x.identifier for x in build_step.platform_configs]
             log.step(f"Starting container image {build_step.container_image}...")
@@ -435,7 +445,7 @@ def build(options: Options, tmp_path: Path) -> None:  # noqa: ARG001
                 image=build_step.container_image,
                 enforce_32_bit=build_step.platform_tag.endswith("i686"),
                 cwd=container_project_path,
-                engine=options.globals.container_engine,
+                engine=build_step.container_engine,
             ) as container:
                 build_in_container(
                     options=options,

cibuildwheel/macos.py

@@ -181,7 +181,9 @@ def setup_python(
 
     log.step("Setting up build environment...")
     venv_path = tmp / "venv"
-    env = virtualenv(base_python, venv_path, dependency_constraint_flags)
+    env = virtualenv(
+        python_configuration.version, base_python, venv_path, dependency_constraint_flags
+    )
     venv_bin_path = venv_path / "bin"
     assert venv_bin_path.exists()
     # Fix issue with site.py setting the wrong `sys.prefix`, `sys.exec_prefix`,
@@ -573,6 +575,10 @@ def build(options: Options, tmp_path: Path) -> None:
                     # check that we are using the Python from the virtual environment
                     call_with_arch("which", "python", env=virtualenv_env)
 
+                    # TODO remove me once virtualenv provides pip>=24.1b1
+                    if config.version == "3.13":
+                        call("python", "-m", "pip", "install", "pip>=24.1b1", env=virtualenv_env)
+
                     if build_options.before_test:
                         before_test_prepared = prepare_command(
                             build_options.before_test,

cibuildwheel/oci_container.py

@@ -11,7 +11,7 @@ import sys
 import typing
 import uuid
 from collections.abc import Mapping, Sequence
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from pathlib import Path, PurePath, PurePosixPath
 from types import TracebackType
 from typing import IO, Dict, Literal
@@ -32,7 +32,7 @@ ContainerEngineName = Literal["docker", "podman"]
 @dataclass(frozen=True)
 class OCIContainerEngineConfig:
     name: ContainerEngineName
-    create_args: Sequence[str] = ()
+    create_args: tuple[str, ...] = field(default_factory=tuple)
     disable_host_mount: bool = False
 
     @staticmethod
@@ -58,7 +58,7 @@ class OCIContainerEngineConfig:
         )
 
         return OCIContainerEngineConfig(
-            name=name, create_args=create_args, disable_host_mount=disable_host_mount
+            name=name, create_args=tuple(create_args), disable_host_mount=disable_host_mount
         )
 
     def options_summary(self) -> str | dict[str, str]:

cibuildwheel/options.py

@@ -75,7 +75,6 @@ class GlobalOptions:
     build_selector: BuildSelector
     test_selector: TestSelector
     architectures: set[Architecture]
-    container_engine: OCIContainerEngineConfig
 
 
 @dataclasses.dataclass(frozen=True)
@@ -95,6 +94,7 @@ class BuildOptions:
     build_verbosity: int
     build_frontend: BuildFrontendConfig | None
     config_settings: str
+    container_engine: OCIContainerEngineConfig
 
     @property
     def package_dir(self) -> Path:
@@ -117,7 +117,7 @@ class BuildOptions:
         return self.globals.architectures
 
 
-Setting = Union[Mapping[str, str], Sequence[str], str, int]
+Setting = Union[Mapping[str, str], Sequence[str], str, int, bool]
 
 
 @dataclasses.dataclass(frozen=True)
@@ -196,7 +196,7 @@ def _resolve_cascade(
         if value is None:
             continue
 
-        if ignore_empty and not value:
+        if ignore_empty and not value and value is not False:
             continue
 
         value_string = _stringify_setting(value, list_sep, table_format)
@@ -258,7 +258,7 @@ def _stringify_setting(
             raise ConfigOptionError(msg)
         return list_sep.join(setting)
 
-    if isinstance(setting, int):
+    if isinstance(setting, (bool, int)):
         return str(setting)
 
     return setting
@@ -516,6 +516,10 @@ class Options:
         skip_config = self.reader.get("skip", env_plat=False, list_sep=" ")
         test_skip = self.reader.get("test-skip", env_plat=False, list_sep=" ")
 
+        free_threaded_support = strtobool(
+            self.reader.get("free-threaded-support", env_plat=False, ignore_empty=True)
+        )
+
         prerelease_pythons = args.prerelease_pythons or strtobool(
             self.env.get("CIBW_PRERELEASE_PYTHONS", "0")
         )
@@ -536,34 +540,23 @@ class Options:
             skip_config = ""
             architectures = Architecture.all_archs(self.platform)
             prerelease_pythons = True
+            free_threaded_support = True
 
         build_selector = BuildSelector(
             build_config=build_config,
             skip_config=skip_config,
             requires_python=requires_python,
             prerelease_pythons=prerelease_pythons,
+            free_threaded_support=free_threaded_support,
         )
         test_selector = TestSelector(skip_config=test_skip)
 
-        container_engine_str = self.reader.get(
-            "container-engine",
-            table_format={"item": "{k}:{v}", "sep": "; ", "quote": shlex.quote},
-        )
-
-        try:
-            container_engine = OCIContainerEngineConfig.from_config_string(container_engine_str)
-        except ValueError as e:
-            msg = f"cibuildwheel: Failed to parse container config. {e}"
-            print(msg, file=sys.stderr)
-            sys.exit(2)
-
         return GlobalOptions(
             package_dir=package_dir,
             output_dir=output_dir,
             build_selector=build_selector,
             test_selector=test_selector,
             architectures=architectures,
-            container_engine=container_engine,
         )
 
     def build_options(self, identifier: str | None) -> BuildOptions:
@@ -643,6 +636,8 @@ class Options:
 
             manylinux_images: dict[str, str] = {}
             musllinux_images: dict[str, str] = {}
+            container_engine: OCIContainerEngineConfig | None = None
+
             if self.platform == "linux":
                 all_pinned_container_images = _get_pinned_container_images()
 
@@ -677,6 +672,18 @@ class Options:
 
                     musllinux_images[build_platform] = image
 
+            container_engine_str = self.reader.get(
+                "container-engine",
+                table_format={"item": "{k}:{v}", "sep": "; ", "quote": shlex.quote},
+            )
+
+            try:
+                container_engine = OCIContainerEngineConfig.from_config_string(container_engine_str)
+            except ValueError as e:
+                msg = f"cibuildwheel: Failed to parse container config. {e}"
+                print(msg, file=sys.stderr)
+                sys.exit(2)
+
             return BuildOptions(
                 globals=self.globals,
                 test_command=test_command,
@@ -693,6 +700,7 @@ class Options:
                 musllinux_images=musllinux_images or None,
                 build_frontend=build_frontend,
                 config_settings=config_settings,
+                container_engine=container_engine,
             )
 
     def check_for_invalid_configuration(self, identifiers: Iterable[str]) -> None:

cibuildwheel/resources/build-platforms.toml

@@ -8,6 +8,7 @@ python_configurations = [
   { identifier = "cp311-manylinux_x86_64", version = "3.11", path_str = "/opt/python/cp311-cp311" },
   { identifier = "cp312-manylinux_x86_64", version = "3.12", path_str = "/opt/python/cp312-cp312" },
   { identifier = "cp313-manylinux_x86_64", version = "3.13", path_str = "/opt/python/cp313-cp313" },
+  { identifier = "cp313t-manylinux_x86_64", version = "3.13", path_str = "/opt/python/cp313-cp313t" },
   { identifier = "cp36-manylinux_i686", version = "3.6", path_str = "/opt/python/cp36-cp36m" },
   { identifier = "cp37-manylinux_i686", version = "3.7", path_str = "/opt/python/cp37-cp37m" },
   { identifier = "cp38-manylinux_i686", version = "3.8", path_str = "/opt/python/cp38-cp38" },
@@ -16,6 +17,7 @@ python_configurations = [
   { identifier = "cp311-manylinux_i686", version = "3.11", path_str = "/opt/python/cp311-cp311" },
   { identifier = "cp312-manylinux_i686", version = "3.12", path_str = "/opt/python/cp312-cp312" },
   { identifier = "cp313-manylinux_i686", version = "3.13", path_str = "/opt/python/cp313-cp313" },
+  { identifier = "cp313t-manylinux_i686", version = "3.13", path_str = "/opt/python/cp313-cp313t" },
   { identifier = "pp37-manylinux_x86_64", version = "3.7", path_str = "/opt/python/pp37-pypy37_pp73" },
   { identifier = "pp38-manylinux_x86_64", version = "3.8", path_str = "/opt/python/pp38-pypy38_pp73" },
   { identifier = "pp39-manylinux_x86_64", version = "3.9", path_str = "/opt/python/pp39-pypy39_pp73" },
@@ -28,6 +30,7 @@ python_configurations = [
   { identifier = "cp311-manylinux_aarch64", version = "3.11", path_str = "/opt/python/cp311-cp311" },
   { identifier = "cp312-manylinux_aarch64", version = "3.12", path_str = "/opt/python/cp312-cp312" },
   { identifier = "cp313-manylinux_aarch64", version = "3.13", path_str = "/opt/python/cp313-cp313" },
+  { identifier = "cp313t-manylinux_aarch64", version = "3.13", path_str = "/opt/python/cp313-cp313t" },
   { identifier = "cp36-manylinux_ppc64le", version = "3.6", path_str = "/opt/python/cp36-cp36m" },
   { identifier = "cp37-manylinux_ppc64le", version = "3.7", path_str = "/opt/python/cp37-cp37m" },
   { identifier = "cp38-manylinux_ppc64le", version = "3.8", path_str = "/opt/python/cp38-cp38" },
@@ -36,6 +39,7 @@ python_configurations = [
   { identifier = "cp311-manylinux_ppc64le", version = "3.11", path_str = "/opt/python/cp311-cp311" },
   { identifier = "cp312-manylinux_ppc64le", version = "3.12", path_str = "/opt/python/cp312-cp312" },
   { identifier = "cp313-manylinux_ppc64le", version = "3.13", path_str = "/opt/python/cp313-cp313" },
+  { identifier = "cp313t-manylinux_ppc64le", version = "3.13", path_str = "/opt/python/cp313-cp313t" },
   { identifier = "cp36-manylinux_s390x", version = "3.6", path_str = "/opt/python/cp36-cp36m" },
   { identifier = "cp37-manylinux_s390x", version = "3.7", path_str = "/opt/python/cp37-cp37m" },
   { identifier = "cp38-manylinux_s390x", version = "3.8", path_str = "/opt/python/cp38-cp38" },
@@ -44,6 +48,7 @@ python_configurations = [
   { identifier = "cp311-manylinux_s390x", version = "3.11", path_str = "/opt/python/cp311-cp311" },
   { identifier = "cp312-manylinux_s390x", version = "3.12", path_str = "/opt/python/cp312-cp312" },
   { identifier = "cp313-manylinux_s390x", version = "3.13", path_str = "/opt/python/cp313-cp313" },
+  { identifier = "cp313t-manylinux_s390x", version = "3.13", path_str = "/opt/python/cp313-cp313t" },
   { identifier = "pp37-manylinux_aarch64", version = "3.7", path_str = "/opt/python/pp37-pypy37_pp73" },
   { identifier = "pp38-manylinux_aarch64", version = "3.8", path_str = "/opt/python/pp38-pypy38_pp73" },
   { identifier = "pp39-manylinux_aarch64", version = "3.9", path_str = "/opt/python/pp39-pypy39_pp73" },
@@ -60,6 +65,7 @@ python_configurations = [
   { identifier = "cp311-musllinux_x86_64", version = "3.11", path_str = "/opt/python/cp311-cp311" },
   { identifier = "cp312-musllinux_x86_64", version = "3.12", path_str = "/opt/python/cp312-cp312" },
   { identifier = "cp313-musllinux_x86_64", version = "3.13", path_str = "/opt/python/cp313-cp313" },
+  { identifier = "cp313t-musllinux_x86_64", version = "3.13", path_str = "/opt/python/cp313-cp313t" },
   { identifier = "cp36-musllinux_i686", version = "3.6", path_str = "/opt/python/cp36-cp36m" },
   { identifier = "cp37-musllinux_i686", version = "3.7", path_str = "/opt/python/cp37-cp37m" },
   { identifier = "cp38-musllinux_i686", version = "3.8", path_str = "/opt/python/cp38-cp38" },
@@ -68,6 +74,7 @@ python_configurations = [
   { identifier = "cp311-musllinux_i686", version = "3.11", path_str = "/opt/python/cp311-cp311" },
   { identifier = "cp312-musllinux_i686", version = "3.12", path_str = "/opt/python/cp312-cp312" },
   { identifier = "cp313-musllinux_i686", version = "3.13", path_str = "/opt/python/cp313-cp313" },
+  { identifier = "cp313t-musllinux_i686", version = "3.13", path_str = "/opt/python/cp313-cp313t" },
   { identifier = "cp36-musllinux_aarch64", version = "3.6", path_str = "/opt/python/cp36-cp36m" },
   { identifier = "cp37-musllinux_aarch64", version = "3.7", path_str = "/opt/python/cp37-cp37m" },
   { identifier = "cp38-musllinux_aarch64", version = "3.8", path_str = "/opt/python/cp38-cp38" },
@@ -76,6 +83,7 @@ python_configurations = [
   { identifier = "cp311-musllinux_aarch64", version = "3.11", path_str = "/opt/python/cp311-cp311" },
   { identifier = "cp312-musllinux_aarch64", version = "3.12", path_str = "/opt/python/cp312-cp312" },
   { identifier = "cp313-musllinux_aarch64", version = "3.13", path_str = "/opt/python/cp313-cp313" },
+  { identifier = "cp313t-musllinux_aarch64", version = "3.13", path_str = "/opt/python/cp313-cp313t" },
   { identifier = "cp36-musllinux_ppc64le", version = "3.6", path_str = "/opt/python/cp36-cp36m" },
   { identifier = "cp37-musllinux_ppc64le", version = "3.7", path_str = "/opt/python/cp37-cp37m" },
   { identifier = "cp38-musllinux_ppc64le", version = "3.8", path_str = "/opt/python/cp38-cp38" },
@@ -84,6 +92,7 @@ python_configurations = [
   { identifier = "cp311-musllinux_ppc64le", version = "3.11", path_str = "/opt/python/cp311-cp311" },
   { identifier = "cp312-musllinux_ppc64le", version = "3.12", path_str = "/opt/python/cp312-cp312" },
   { identifier = "cp313-musllinux_ppc64le", version = "3.13", path_str = "/opt/python/cp313-cp313" },
+  { identifier = "cp313t-musllinux_ppc64le", version = "3.13", path_str = "/opt/python/cp313-cp313t" },
   { identifier = "cp36-musllinux_s390x", version = "3.6", path_str = "/opt/python/cp36-cp36m" },
   { identifier = "cp37-musllinux_s390x", version = "3.7", path_str = "/opt/python/cp37-cp37m" },
   { identifier = "cp38-musllinux_s390x", version = "3.8", path_str = "/opt/python/cp38-cp38" },
@@ -92,6 +101,7 @@ python_configurations = [
   { identifier = "cp311-musllinux_s390x", version = "3.11", path_str = "/opt/python/cp311-cp311" },
   { identifier = "cp312-musllinux_s390x", version = "3.12", path_str = "/opt/python/cp312-cp312" },
   { identifier = "cp313-musllinux_s390x", version = "3.13", path_str = "/opt/python/cp313-cp313" },
+  { identifier = "cp313t-musllinux_s390x", version = "3.13", path_str = "/opt/python/cp313-cp313t" },
 ]
 
 [macos]
@@ -142,12 +152,15 @@ python_configurations = [
   { identifier = "cp312-win32", version = "3.12.3", arch = "32" },
   { identifier = "cp312-win_amd64", version = "3.12.3", arch = "64" },
   { identifier = "cp313-win32", version = "3.13.0-b1", arch = "32" },
+  { identifier = "cp313t-win32", version = "3.13.0-b1", arch = "32" },
   { identifier = "cp313-win_amd64", version = "3.13.0-b1", arch = "64" },
+  { identifier = "cp313t-win_amd64", version = "3.13.0-b1", arch = "64" },
   { identifier = "cp39-win_arm64", version = "3.9.10", arch = "ARM64" },
   { identifier = "cp310-win_arm64", version = "3.10.11", arch = "ARM64" },
   { identifier = "cp311-win_arm64", version = "3.11.9", arch = "ARM64" },
   { identifier = "cp312-win_arm64", version = "3.12.3", arch = "ARM64" },
   { identifier = "cp313-win_arm64", version = "3.13.0-b1", arch = "ARM64" },
+  { identifier = "cp313t-win_arm64", version = "3.13.0-b1", arch = "ARM64" },
   { identifier = "pp37-win_amd64", version = "3.7", arch = "64", url = "https://downloads.python.org/pypy/pypy3.7-v7.3.9-win64.zip" },
   { identifier = "pp38-win_amd64", version = "3.8", arch = "64", url = "https://downloads.python.org/pypy/pypy3.8-v7.3.11-win64.zip" },
   { identifier = "pp39-win_amd64", version = "3.9", arch = "64", url = "https://downloads.python.org/pypy/pypy3.9-v7.3.16-win64.zip" },

cibuildwheel/resources/cibuildwheel.schema.json

@@ -255,6 +255,12 @@
       ],
       "title": "CIBW_ENVIRONMENT_PASS"
     },
+    "free-threaded-support": {
+      "type": "boolean",
+      "default": false,
+      "description": "The project supports free-threaded builds of Python (PEP703)",
+      "title": "CIBW_FREE_THREADED_SUPPORT"
+    },
     "manylinux-aarch64-image": {
       "type": "string",
       "description": "Specify alternative manylinux / musllinux container images",
@@ -491,6 +497,9 @@
           "config-settings": {
             "$ref": "#/properties/config-settings"
           },
+          "container-engine": {
+            "$ref": "#/properties/container-engine"
+          },
           "dependency-versions": {
             "$ref": "#/properties/dependency-versions"
           },
@@ -579,6 +588,9 @@
         "config-settings": {
           "$ref": "#/properties/config-settings"
         },
+        "container-engine": {
+          "$ref": "#/properties/container-engine"
+        },
         "environment": {
           "$ref": "#/properties/environment"
         },

cibuildwheel/resources/constraints-python310.txt

@@ -3,7 +3,9 @@
 altgraph==0.17.4
     # via macholib
 build==1.2.1
+    # via -r cibuildwheel/resources/constraints.in
 delocate==0.11.0
+    # via -r cibuildwheel/resources/constraints.in
 distlib==0.3.8
     # via virtualenv
 filelock==3.14.0
@@ -17,7 +19,8 @@ packaging==24.0
     #   build
     #   delocate
 pip==24.0
-platformdirs==4.2.1
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.2.2
     # via virtualenv
 pyproject-hooks==1.1.0
     # via build
@@ -25,6 +28,7 @@ tomli==2.0.1
     # via build
 typing-extensions==4.11.0
     # via delocate
-virtualenv==20.26.1
-zipp==3.18.1
+virtualenv==20.26.2
+    # via -r cibuildwheel/resources/constraints.in
+zipp==3.18.2
     # via importlib-metadata

cibuildwheel/resources/constraints-python311.txt

@@ -3,7 +3,9 @@
 altgraph==0.17.4
     # via macholib
 build==1.2.1
+    # via -r cibuildwheel/resources/constraints.in
 delocate==0.11.0
+    # via -r cibuildwheel/resources/constraints.in
 distlib==0.3.8
     # via virtualenv
 filelock==3.14.0
@@ -15,10 +17,12 @@ packaging==24.0
     #   build
     #   delocate
 pip==24.0
-platformdirs==4.2.1
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.2.2
     # via virtualenv
 pyproject-hooks==1.1.0
     # via build
 typing-extensions==4.11.0
     # via delocate
-virtualenv==20.26.1
+virtualenv==20.26.2
+    # via -r cibuildwheel/resources/constraints.in

cibuildwheel/resources/constraints-python312.txt

@@ -3,7 +3,9 @@
 altgraph==0.17.4
     # via macholib
 build==1.2.1
+    # via -r cibuildwheel/resources/constraints.in
 delocate==0.11.0
+    # via -r cibuildwheel/resources/constraints.in
 distlib==0.3.8
     # via virtualenv
 filelock==3.14.0
@@ -15,10 +17,12 @@ packaging==24.0
     #   build
     #   delocate
 pip==24.0
-platformdirs==4.2.1
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.2.2
     # via virtualenv
 pyproject-hooks==1.1.0
     # via build
 typing-extensions==4.11.0
     # via delocate
-virtualenv==20.26.1
+virtualenv==20.26.2
+    # via -r cibuildwheel/resources/constraints.in

cibuildwheel/resources/constraints-python313.txt

@@ -3,7 +3,9 @@
 altgraph==0.17.4
     # via macholib
 build==1.2.1
+    # via -r cibuildwheel/resources/constraints.in
 delocate==0.11.0
+    # via -r cibuildwheel/resources/constraints.in
 distlib==0.3.8
     # via virtualenv
 filelock==3.14.0
@@ -14,11 +16,13 @@ packaging==24.0
     # via
     #   build
     #   delocate
-pip==24.0
-platformdirs==4.2.1
+pip==24.1b1
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.2.2
     # via virtualenv
 pyproject-hooks==1.1.0
     # via build
 typing-extensions==4.11.0
     # via delocate
-virtualenv==20.26.1
+virtualenv==20.26.2
+    # via -r cibuildwheel/resources/constraints.in

cibuildwheel/resources/constraints-python37.txt

@@ -3,7 +3,9 @@
 altgraph==0.17.4
     # via macholib
 build==1.1.1
+    # via -r cibuildwheel/resources/constraints.in
 delocate==0.11.0
+    # via -r cibuildwheel/resources/constraints.in
 distlib==0.3.8
     # via virtualenv
 filelock==3.12.2
@@ -19,6 +21,7 @@ packaging==24.0
     #   build
     #   delocate
 pip==24.0
+    # via -r cibuildwheel/resources/constraints.in
 platformdirs==4.0.0
     # via virtualenv
 pyproject-hooks==1.1.0
@@ -30,6 +33,7 @@ typing-extensions==4.7.1
     #   delocate
     #   importlib-metadata
     #   platformdirs
-virtualenv==20.26.1
+virtualenv==20.26.2
+    # via -r cibuildwheel/resources/constraints.in
 zipp==3.15.0
     # via importlib-metadata

cibuildwheel/resources/constraints-python38.txt

@@ -3,7 +3,9 @@
 altgraph==0.17.4
     # via macholib
 build==1.2.1
+    # via -r cibuildwheel/resources/constraints.in
 delocate==0.11.0
+    # via -r cibuildwheel/resources/constraints.in
 distlib==0.3.8
     # via virtualenv
 filelock==3.14.0
@@ -17,7 +19,8 @@ packaging==24.0
     #   build
     #   delocate
 pip==24.0
-platformdirs==4.2.1
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.2.2
     # via virtualenv
 pyproject-hooks==1.1.0
     # via build
@@ -25,6 +28,7 @@ tomli==2.0.1
     # via build
 typing-extensions==4.11.0
     # via delocate
-virtualenv==20.26.1
-zipp==3.18.1
+virtualenv==20.26.2
+    # via -r cibuildwheel/resources/constraints.in
+zipp==3.18.2
     # via importlib-metadata

cibuildwheel/resources/constraints-python39.txt

@@ -3,7 +3,9 @@
 altgraph==0.17.4
     # via macholib
 build==1.2.1
+    # via -r cibuildwheel/resources/constraints.in
 delocate==0.11.0
+    # via -r cibuildwheel/resources/constraints.in
 distlib==0.3.8
     # via virtualenv
 filelock==3.14.0
@@ -17,7 +19,8 @@ packaging==24.0
     #   build
     #   delocate
 pip==24.0
-platformdirs==4.2.1
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.2.2
     # via virtualenv
 pyproject-hooks==1.1.0
     # via build
@@ -25,6 +28,7 @@ tomli==2.0.1
     # via build
 typing-extensions==4.11.0
     # via delocate
-virtualenv==20.26.1
-zipp==3.18.1
+virtualenv==20.26.2
+    # via -r cibuildwheel/resources/constraints.in
+zipp==3.18.2
     # via importlib-metadata

cibuildwheel/resources/constraints.in

@@ -1,4 +1,5 @@
-pip
+pip>=24.1b1 ; python_version >= '3.13'
+pip ; python_version < '3.13'
 build
 delocate
 virtualenv

cibuildwheel/resources/constraints.txt

@@ -3,7 +3,9 @@
 altgraph==0.17.4
     # via macholib
 build==1.2.1
+    # via -r cibuildwheel/resources/constraints.in
 delocate==0.11.0
+    # via -r cibuildwheel/resources/constraints.in
 distlib==0.3.8
     # via virtualenv
 filelock==3.14.0
@@ -15,10 +17,12 @@ packaging==24.0
     #   build
     #   delocate
 pip==24.0
-platformdirs==4.2.1
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.2.2
     # via virtualenv
 pyproject-hooks==1.1.0
     # via build
 typing-extensions==4.11.0
     # via delocate
-virtualenv==20.26.1
+virtualenv==20.26.2
+    # via -r cibuildwheel/resources/constraints.in

cibuildwheel/resources/defaults.toml

@@ -2,6 +2,7 @@
 build = "*"
 skip = ""
 test-skip = ""
+free-threaded-support = false
 
 archs = ["auto"]
 build-frontend = "default"

cibuildwheel/resources/pinned_docker_images.cfg

@@ -1,54 +1,54 @@
 [x86_64]
 manylinux1 = quay.io/pypa/manylinux1_x86_64:2024-04-29-76807b8
 manylinux2010 = quay.io/pypa/manylinux2010_x86_64:2022-08-05-4535177
-manylinux2014 = quay.io/pypa/manylinux2014_x86_64:2024-05-10-7415d48
+manylinux2014 = quay.io/pypa/manylinux2014_x86_64:2024-05-13-0983f6f
 manylinux_2_24 = quay.io/pypa/manylinux_2_24_x86_64:2022-12-26-0d38463
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_x86_64:2024-05-10-7415d48
-musllinux_1_1 = quay.io/pypa/musllinux_1_1_x86_64:2024-05-10-7415d48
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_x86_64:2024-05-10-7415d48
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_x86_64:2024-05-13-0983f6f
+musllinux_1_1 = quay.io/pypa/musllinux_1_1_x86_64:2024-05-13-0983f6f
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_x86_64:2024-05-13-0983f6f
 
 [i686]
 manylinux1 = quay.io/pypa/manylinux1_i686:2024-04-29-76807b8
 manylinux2010 = quay.io/pypa/manylinux2010_i686:2022-08-05-4535177
-manylinux2014 = quay.io/pypa/manylinux2014_i686:2024-05-10-7415d48
+manylinux2014 = quay.io/pypa/manylinux2014_i686:2024-05-13-0983f6f
 manylinux_2_24 = quay.io/pypa/manylinux_2_24_i686:2022-12-26-0d38463
-musllinux_1_1 = quay.io/pypa/musllinux_1_1_i686:2024-05-10-7415d48
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_i686:2024-05-10-7415d48
+musllinux_1_1 = quay.io/pypa/musllinux_1_1_i686:2024-05-13-0983f6f
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_i686:2024-05-13-0983f6f
 
 [pypy_x86_64]
 manylinux2010 = quay.io/pypa/manylinux2010_x86_64:2022-08-05-4535177
-manylinux2014 = quay.io/pypa/manylinux2014_x86_64:2024-05-10-7415d48
+manylinux2014 = quay.io/pypa/manylinux2014_x86_64:2024-05-13-0983f6f
 manylinux_2_24 = quay.io/pypa/manylinux_2_24_x86_64:2022-12-26-0d38463
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_x86_64:2024-05-10-7415d48
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_x86_64:2024-05-13-0983f6f
 
 [pypy_i686]
 manylinux2010 = quay.io/pypa/manylinux2010_i686:2022-08-05-4535177
-manylinux2014 = quay.io/pypa/manylinux2014_i686:2024-05-10-7415d48
+manylinux2014 = quay.io/pypa/manylinux2014_i686:2024-05-13-0983f6f
 manylinux_2_24 = quay.io/pypa/manylinux_2_24_i686:2022-12-26-0d38463
 
 [aarch64]
-manylinux2014 = quay.io/pypa/manylinux2014_aarch64:2024-05-10-7415d48
+manylinux2014 = quay.io/pypa/manylinux2014_aarch64:2024-05-13-0983f6f
 manylinux_2_24 = quay.io/pypa/manylinux_2_24_aarch64:2022-12-26-0d38463
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_aarch64:2024-05-10-7415d48
-musllinux_1_1 = quay.io/pypa/musllinux_1_1_aarch64:2024-05-10-7415d48
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_aarch64:2024-05-10-7415d48
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_aarch64:2024-05-13-0983f6f
+musllinux_1_1 = quay.io/pypa/musllinux_1_1_aarch64:2024-05-13-0983f6f
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_aarch64:2024-05-13-0983f6f
 
 [ppc64le]
-manylinux2014 = quay.io/pypa/manylinux2014_ppc64le:2024-05-10-7415d48
+manylinux2014 = quay.io/pypa/manylinux2014_ppc64le:2024-05-13-0983f6f
 manylinux_2_24 = quay.io/pypa/manylinux_2_24_ppc64le:2022-12-26-0d38463
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_ppc64le:2024-05-10-7415d48
-musllinux_1_1 = quay.io/pypa/musllinux_1_1_ppc64le:2024-05-10-7415d48
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_ppc64le:2024-05-10-7415d48
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_ppc64le:2024-05-13-0983f6f
+musllinux_1_1 = quay.io/pypa/musllinux_1_1_ppc64le:2024-05-13-0983f6f
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_ppc64le:2024-05-13-0983f6f
 
 [s390x]
-manylinux2014 = quay.io/pypa/manylinux2014_s390x:2024-05-10-7415d48
+manylinux2014 = quay.io/pypa/manylinux2014_s390x:2024-05-13-0983f6f
 manylinux_2_24 = quay.io/pypa/manylinux_2_24_s390x:2022-12-26-0d38463
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_s390x:2024-05-10-7415d48
-musllinux_1_1 = quay.io/pypa/musllinux_1_1_s390x:2024-05-10-7415d48
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_s390x:2024-05-10-7415d48
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_s390x:2024-05-13-0983f6f
+musllinux_1_1 = quay.io/pypa/musllinux_1_1_s390x:2024-05-13-0983f6f
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_s390x:2024-05-13-0983f6f
 
 [pypy_aarch64]
-manylinux2014 = quay.io/pypa/manylinux2014_aarch64:2024-05-10-7415d48
+manylinux2014 = quay.io/pypa/manylinux2014_aarch64:2024-05-13-0983f6f
 manylinux_2_24 = quay.io/pypa/manylinux_2_24_aarch64:2022-12-26-0d38463
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_aarch64:2024-05-10-7415d48
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_aarch64:2024-05-13-0983f6f
 

cibuildwheel/resources/virtualenv.toml

@@ -1,2 +1,2 @@
-version = "20.21.1"
-url = "https://github.com/pypa/get-virtualenv/blob/20.21.1/public/virtualenv.pyz?raw=true"
+py36 = { version = "20.21.1", url = "https://github.com/pypa/get-virtualenv/blob/20.21.1/public/virtualenv.pyz?raw=true" }
+default = { version = "20.26.2", url = "https://github.com/pypa/get-virtualenv/blob/20.26.2/public/virtualenv.pyz?raw=true" }

cibuildwheel/util.py

@@ -238,13 +238,17 @@ class BuildSelector:
     requires_python: SpecifierSet | None = None
 
     # a pattern that skips prerelease versions, when include_prereleases is False.
-    PRERELEASE_SKIP: ClassVar[str] = "cp313-*"
+    PRERELEASE_SKIP: ClassVar[str] = "cp313-* cp313t-*"
     prerelease_pythons: bool = False
 
+    free_threaded_support: bool = False
+
     def __call__(self, build_id: str) -> bool:
         # Filter build selectors by python_requires if set
         if self.requires_python is not None:
             py_ver_str = build_id.split("-")[0]
+            if py_ver_str.endswith("t"):
+                py_ver_str = py_ver_str[:-1]
             major = int(py_ver_str[2])
             minor = int(py_ver_str[3:])
             version = Version(f"{major}.{minor}.99")
@@ -255,6 +259,10 @@ class BuildSelector:
         if not self.prerelease_pythons and selector_matches(self.PRERELEASE_SKIP, build_id):
             return False
 
+        # filter out free threaded pythons if self.free_threaded_support is False
+        if not self.free_threaded_support and selector_matches("*t-*", build_id):
+            return False
+
         should_build = selector_matches(self.build_config, build_id)
         should_skip = selector_matches(self.skip_config, build_id)
 
@@ -266,6 +274,7 @@ class BuildSelector:
             "skip_config": self.skip_config,
             "requires_python": str(self.requires_python),
             "prerelease_pythons": self.prerelease_pythons,
+            "free_threaded_support": self.free_threaded_support,
         }
 
 
@@ -526,12 +535,15 @@ def get_pip_version(env: Mapping[str, str]) -> str:
 
 
 @lru_cache(maxsize=None)
-def _ensure_virtualenv() -> Path:
+def _ensure_virtualenv(version: str) -> Path:
+    version_parts = version.split(".")
+    key = f"py{version_parts[0]}{version_parts[1]}"
     input_file = resources_dir / "virtualenv.toml"
     with input_file.open("rb") as f:
         loaded_file = tomllib.load(f)
-    version = str(loaded_file["version"])
-    url = str(loaded_file["url"])
+    configuration = loaded_file.get(key, loaded_file["default"])
+    version = str(configuration["version"])
+    url = str(configuration["url"])
     path = CIBW_CACHE_PATH / f"virtualenv-{version}.pyz"
     with FileLock(str(path) + ".lock"):
         if not path.exists():
@@ -587,10 +599,10 @@ def _parse_constraints_for_virtualenv(
 
 
 def virtualenv(
-    python: Path, venv_path: Path, dependency_constraint_flags: Sequence[PathOrStr]
+    version: str, python: Path, venv_path: Path, dependency_constraint_flags: Sequence[PathOrStr]
 ) -> dict[str, str]:
     assert python.exists()
-    virtualenv_app = _ensure_virtualenv()
+    virtualenv_app = _ensure_virtualenv(version)
     allowed_seed_packages = ["pip", "setuptools", "wheel"]
     constraints = _parse_constraints_for_virtualenv(
         allowed_seed_packages, dependency_constraint_flags
@@ -642,10 +654,13 @@ def find_compatible_wheel(wheels: Sequence[T], identifier: str) -> T | None:
     """
 
     interpreter, platform = identifier.split("-")
+    free_threaded = interpreter.endswith("t")
+    if free_threaded:
+        interpreter = interpreter[:-1]
     for wheel in wheels:
         _, _, _, tags = parse_wheel_filename(wheel.name)
         for tag in tags:
-            if tag.abi == "abi3":
+            if tag.abi == "abi3" and not free_threaded:
                 # ABI3 wheels must start with cp3 for impl and tag
                 if not (interpreter.startswith("cp3") and tag.interpreter.startswith("cp3")):
                     continue

cibuildwheel/windows.py

@@ -44,7 +44,9 @@ from .util import (
 )
 
 
-def get_nuget_args(version: str, arch: str, output_directory: Path) -> list[str]:
+def get_nuget_args(
+    version: str, arch: str, free_threaded: bool, output_directory: Path
+) -> list[str]:
     package_name = {
         "32": "pythonx86",
         "64": "python",
@@ -53,6 +55,8 @@ def get_nuget_args(version: str, arch: str, output_directory: Path) -> list[str]
         "x86": "pythonx86",
         "AMD64": "python",
     }[arch]
+    if free_threaded:
+        package_name = f"{package_name}-freethreaded"
     return [
         package_name,
         "-Version",
@@ -106,11 +110,16 @@ def _ensure_nuget() -> Path:
     return nuget
 
 
-def install_cpython(version: str, arch: str) -> Path:
+def install_cpython(configuration: PythonConfiguration, arch: str | None = None) -> Path:
+    version = configuration.version
+    free_threaded = "t-" in configuration.identifier
+    if arch is None:
+        arch = configuration.arch
     base_output_dir = CIBW_CACHE_PATH / "nuget-cpython"
-    nuget_args = get_nuget_args(version, arch, base_output_dir)
+    nuget_args = get_nuget_args(version, arch, free_threaded, base_output_dir)
     installation_path = base_output_dir / (nuget_args[0] + "." + version) / "tools"
-    with FileLock(str(base_output_dir) + f"-{version}-{arch}.lock"):
+    free_threaded_str = "-freethreaded" if free_threaded else ""
+    with FileLock(str(base_output_dir) + f"-{version}{free_threaded_str}-{arch}.lock"):
         if not installation_path.exists():
             nuget = _ensure_nuget()
             call(nuget, "install", *nuget_args)
@@ -224,18 +233,14 @@ def setup_python(
     log.step(f"Installing Python {implementation_id}...")
     if implementation_id.startswith("cp"):
         native_arch = platform_module.machine()
+        base_python = install_cpython(python_configuration)
         if python_configuration.arch == "ARM64" != native_arch:
             # To cross-compile for ARM64, we need a native CPython to run the
             # build, and a copy of the ARM64 import libraries ('.\libs\*.lib')
             # for any extension modules.
-            python_libs_base = install_cpython(
-                python_configuration.version, python_configuration.arch
-            )
-            python_libs_base = python_libs_base.parent / "libs"
+            python_libs_base = base_python.parent / "libs"
             log.step(f"Installing native Python {native_arch} for cross-compilation...")
-            base_python = install_cpython(python_configuration.version, native_arch)
-        else:
-            base_python = install_cpython(python_configuration.version, python_configuration.arch)
+            base_python = install_cpython(python_configuration, arch=native_arch)
     elif implementation_id.startswith("pp"):
         assert python_configuration.url is not None
         base_python = install_pypy(tmp, python_configuration.arch, python_configuration.url)
@@ -246,7 +251,9 @@ def setup_python(
 
     log.step("Setting up build environment...")
     venv_path = tmp / "venv"
-    env = virtualenv(base_python, venv_path, dependency_constraint_flags)
+    env = virtualenv(
+        python_configuration.version, base_python, venv_path, dependency_constraint_flags
+    )
 
     # set up environment variables for run_with_env
     env["PYTHON_VERSION"] = python_configuration.version
@@ -519,6 +526,10 @@ def build(options: Options, tmp_path: Path) -> None:
                 # check that we are using the Python from the virtual environment
                 call("where", "python", env=virtualenv_env)
 
+                # TODO remove me once virtualenv provides pip>=24.1b1
+                if config.version.startswith("3.13."):
+                    call("python", "-m", "pip", "install", "--pre", "-U", "pip", env=virtualenv_env)
+
                 if build_options.before_test:
                     before_test_prepared = prepare_command(
                         build_options.before_test,

docs/changelog.md

@@ -4,14 +4,27 @@ title: Changelog
 
 # Changelog
 
+### v2.18.1
+
+- 🌟 Add free-threaded Linux and Windows builds for 3.13. New identifiers `cp313t-*`, new option `CIBW_FREE_THREADED_SUPPORT`/`tool.cibuildwheel.free-threaded-support` required to opt-in. [See the docs](https://cibuildwheel.pypa.io/en/stable/options/#free-threaded-support) for more information. (#1831)
+- ✨ The `container-engine` is now a build (non-global) option. (#1792)
+- 🛠 The build backend for cibuildwheel is now hatchling. (#1297)
+- 🛠 Significant improvements and modernization to our noxfile. (#1823)
+- 🛠 Use pylint's new GitHub Actions reporter instead of a custom matcher. (#1823)
+- 🛠 Unpin virtualenv updates for Python 3.7+ (#1830)
+- 🐛 Fix running linux tests from Windows or macOS ARM. (#1788)
+- 📚 Fix our documentation build. (#1821)
+
+
 ### v2.18.0
 
 _12 May 2024_
 
-- ✨ Adds CPython 3.13 support, under the prerelease flag [CIBW_PRERELEASE_PYTHONS](https://cibuildwheel.pypa.io/en/stable/options/#prerelease-pythons). This version of cibuildwheel uses 3.13.0b1. Free-threading mode is not available yet, waiting on official binaries (planned for beta 2) and pip support.
+- ✨ Adds CPython 3.13 support, under the prerelease flag [CIBW_PRERELEASE_PYTHONS](https://cibuildwheel.pypa.io/en/stable/options/#prerelease-pythons). This version of cibuildwheel uses 3.13.0b1. Free-threading mode is not available yet (#1657), waiting on official binaries (planned for beta 2) and pip support.
 
-    While CPython is in beta, the ABI can change, so your wheels might not be compatible with the final release. For this reason, we don't recommend distributing wheels until RC1, at which point 3.13 will be available in cibuildwheel without the flag. (#1816)
-- ✨ Musllinux now defaults to `musllinux_1_2`. You can set the older `manylinux_1_1` via config if needed. (#1817)
+    _While CPython is in beta, the ABI can change, so your wheels might not be compatible with the final release. For this reason, we don't recommend distributing wheels until RC1, at which point 3.13 will be available in cibuildwheel without the flag._ (#1815)
+
+- ✨ Musllinux now defaults to `musllinux_1_2`. You can set the older `musllinux_1_1` via config if needed. (#1817)
 - 🛠 No longer pre-seed setuptools/wheel in virtual environments (#1819)
 - 🛠 Respect the constraints file when building with pip, matching build (#1818)
 - 🛠 Use uv to compile our pinned dependencies, 10x faster and doesn't require special setup (#1778)
@@ -26,14 +39,14 @@ _12 May 2024_
 _11 March 2024_
 
 - 🌟 Adds the ability to inherit configuration in TOML overrides. This makes certain configurations much simpler. If you're overriding an option like `before-build` or `environment`, and you just want to add an  extra command or environment variable, you can just append (or prepend) to the previous config. See [the docs](https://cibuildwheel.pypa.io/en/stable/options/#inherit) for more information. (#1730)
-- 🌟 Adds official support for native arm64 macOS GitHub runners. To use them, just specify `macos-14` as an `os` of your job in your workflow file. You can also keep `macos-13` in your build matrix to build x86_64. Check out the new [GitHub Actions example config](https://cibuildwheel.pypa.io/en/stable/setup/#github-actions).
+- 🌟 Adds official support for native `arm64` macOS GitHub runners. To use them, just specify `macos-14` as an `os` of your job in your workflow file. You can also keep `macos-13` in your build matrix to build `x86_64`. Check out the new [GitHub Actions example config](https://cibuildwheel.pypa.io/en/stable/setup/#github-actions).
 - ✨ You no longer need to specify `--platform` to run cibuildwheel locally! Instead it will detect your platform automatically. This was a safety feature, no longer necessary. (#1727)
 - 🛠 Removed setuptools and wheel pinned versions. This only affects old-style projects without a `pyproject.toml`, projects with `pyproject.toml` are already getting fresh versions of their `build-system.requires` installed into an isolated environment. (#1725)
 - 🛠 Improve how the GitHub Action passes arguments (#1757)
 - 🛠 Remove a system-wide install of pipx in the GitHub Action (#1745)
-- 🐛 No longer will cibuildwheel override the PIP_CONSTRAINT environment variable when using the `build` frontend. Instead it will be extended. (#1675)
-- 🐛 Fix a bug where building and testing both x86_86 and arm64 wheels on the same runner caused the wrong architectures in the test environment (#1750)
-- 🐛 Fix a bug that prevented testing a CPython 3.8 wheel targeting macOS 11+ on x86_64 (#1768)
+- 🐛 No longer will cibuildwheel override the `PIP_CONSTRAINT` environment variable when using the `build` frontend. Instead it will be extended. (#1675)
+- 🐛 Fix a bug where building and testing both `x86_86` and `arm64` wheels on the same runner caused the wrong architectures in the test environment (#1750)
+- 🐛 Fix a bug that prevented testing a CPython 3.8 wheel targeting macOS 11+ on `x86_64` (#1768)
 - 📚 Moved the docs onto the official PyPA domain - they're now available at https://cibuildwheel.pypa.io . (#1775)
 - 📚 Docs and examples improvements (#1762, #1734)
 
@@ -110,7 +123,7 @@ _10 July 2023_
 - 🛠 Updates the prerelease CPython 3.12 version to 3.12.0b3.
 - ✨ Allow the use of the `{wheel}` placeholder in CIBW_TEST_COMMAND (#1533)
 - 📚 Docs & examples updates (#1532, #1416)
-- ⚠️ Removed support for running cibuildwheel in Python 3.7. Python 3.7 is EOL. However, cibuildwheel continues to build Python 3.7 wheels for the moment. (#1175)
+- ⚠️  Removed support for running cibuildwheel in Python 3.7. Python 3.7 is EOL. However, cibuildwheel continues to build Python 3.7 wheels for the moment. (#1175)
 
 ### v2.13.1
 

docs/data/projects.yml

@@ -26,7 +26,7 @@
   notes: A simple C extension, without external dependencies
 
 - name: websockets
-  gh: aaugustin/websockets
+  gh: python-websockets/websockets
   ci: [travisci]
   ci_config: .travis.yml
   os: [apple, linux]
@@ -325,12 +325,12 @@
   notes: Full range of wheels for setuptools rust, with auto release and PyPI deploy.
 
 - name: python-snappy
-  gh: andrix/python-snappy
+  gh: intake/python-snappy
   ci: [github]
   os: [apple, linux, windows]
 
 - name: sourmash
-  gh: dib-lab/sourmash
+  gh: sourmash-bio/sourmash
   ci: [github]
   os: [apple, linux, windows]
 
@@ -418,7 +418,7 @@
   notes: Tornado is a Python web framework and asynchronous networking library. Uses stable ABI for a small C extension.
 
 - name: pytorch-fairseq
-  gh: pytorch/fairseq
+  gh: facebookresearch/fairseq
   ci: [github]
   os: [apple, linux]
 
@@ -475,7 +475,7 @@
   os: [apple, linux, windows]
 
 - name: OpenSpiel
-  gh: deepmind/open_spiel
+  gh: google-deepmind/open_spiel
   ci: [github]
   os: [apple, linux]
 
@@ -505,7 +505,7 @@
   os: [apple, linux, windows]
 
 - name: OpenTimelineIO
-  gh: PixarAnimationStudios/OpenTimelineIO
+  gh: AcademySoftwareFoundation/OpenTimelineIO
   ci: [github]
   os: [apple, linux, windows]
 
@@ -584,7 +584,7 @@
   notes: Includes GPU support for linux wheels
 
 - name: power-grid-model
-  gh: alliander-opensource/power-grid-model
+  gh: PowerGridModel/power-grid-model
   ci: [github]
   os: [windows, apple, linux]
   notes: Python/C++ library for distribution power system analysis

docs/faq.md

@@ -142,7 +142,7 @@ There are two suggested methods for keeping cibuildwheel up to date that instead
 If you use GitHub Actions for builds, you can use cibuildwheel as an action:
 
 ```yaml
-uses: pypa/cibuildwheel@v2.18.0
+uses: pypa/cibuildwheel@v2.18.1
 ```
 
 This is a composite step that just runs cibuildwheel using pipx. You can set command-line options as `with:` parameters, and use `env:` as normal.
@@ -164,7 +164,7 @@ The second option, and the only one that supports other CI systems, is using a `
 
 ```bash
 # requirements-cibw.txt
-cibuildwheel==2.18.0
+cibuildwheel==2.18.1
 ```
 
 Then your install step would have `python -m pip install -r requirements-cibw.txt` in it. Your `.github/dependabot.yml` file could look like this:
@@ -328,7 +328,7 @@ Solutions to this vary, but the simplest is to use pipx:
 # most runners have pipx preinstalled, but in case you don't
 python3 -m pip install pipx
 
-pipx run cibuildwheel==2.18.0 --output-dir wheelhouse
+pipx run cibuildwheel==2.18.1 --output-dir wheelhouse
 pipx run twine upload wheelhouse/*.whl
 ```
 

docs/main.py

@@ -1,10 +1,10 @@
 from __future__ import annotations
 
+import os
 import subprocess
+import sysconfig
 from typing import Any
 
-# Requires Python 3.7+
-
 
 def define_env(env: Any) -> None:
     "Hook function for mkdocs-macros"
@@ -12,4 +12,7 @@ def define_env(env: Any) -> None:
     @env.macro
     def subprocess_run(*args: str) -> str:
         "Run a subprocess and return the stdout"
-        return subprocess.run(args, check=True, capture_output=True, text=True).stdout
+        env = os.environ.copy()
+        scripts = sysconfig.get_path("scripts")
+        env["PATH"] = f"{scripts}{os.pathsep}{env.get('PATH', '')}"
+        return subprocess.run(args, check=True, capture_output=True, text=True, env=env).stdout

docs/options.md

@@ -408,6 +408,53 @@ See the [cibuildwheel 1 documentation](https://cibuildwheel.pypa.io/en/1.x/) for
   }
 </style>
 
+### `CIBW_FREE_THREADED_SUPPORT` {: #free-threaded-support}
+
+> Choose whether free-threaded variants should be built
+
+[PEP 703](https://www.python.org/dev/peps/pep-0703) introduced variants of CPython that can be built without the Global Interpreter Lock (GIL).
+Those variants are also known as free-threaded / no-gil.
+
+Building for free-threaded variants is disabled by default.
+
+Building can be enabled by setting this option to `true`. The free-threaded compatible wheels will be built in addition to the standard wheels.
+
+This option doesn't support overrides.
+If you need to enable/disable it per platform or python version, set this option to `true` and use [`CIBW_BUILD`](#build-skip)/[`CIBW_SKIP`](#build-skip) options to filter the builds.
+
+The build identifiers for those variants have a `t` suffix in their `python_tag` (e.g. `cp313t-manylinux_x86_64`)
+
+!!! note
+    This feature is experimental: [What’s New In Python 3.13](https://docs.python.org/3.13/whatsnew/3.13.html#free-threaded-cpython)
+
+#### Examples
+
+!!! tab examples "Environment variables"
+
+    ```yaml
+    # Enable free-threaded support
+    CIBW_FREE_THREADED_SUPPORT: 1
+
+    # Skip building free-threaded compatible wheels on Windows
+    CIBW_FREE_THREADED_SUPPORT: 1
+    CIBW_SKIP: *t-win*
+    ```
+
+    It is generally recommended to use `free-threaded-support` in a config file as you can statically declare that you
+    support free-threaded builds.
+
+!!! tab examples "pyproject.toml"
+
+    ```toml
+    [tool.cibuildwheel]
+    # Enable free-threaded support
+    free-threaded-support = true
+
+    # Skip building free-threaded compatible wheels on Windows
+    free-threaded-support = true
+    skip = "*t-win*"
+    ```
+
 ### `CIBW_ARCHS` {: #archs}
 > Change the architectures built on your machine by default.
 

docs/setup.md

@@ -154,7 +154,7 @@ To build Linux, Mac, and Windows wheels using GitHub Actions, create a `.github/
           - uses: actions/checkout@v4
 
           - name: Build wheels
-            run: pipx run cibuildwheel==2.18.0
+            run: pipx run cibuildwheel==2.18.1
 
           - uses: actions/upload-artifact@v4
             with:
@@ -191,7 +191,7 @@ To build Linux, Mac, and Windows wheels using GitHub Actions, create a `.github/
           - uses: actions/setup-python@v5
 
           - name: Install cibuildwheel
-            run: python -m pip install cibuildwheel==2.18.0
+            run: python -m pip install cibuildwheel==2.18.1
 
           - name: Build wheels
             run: python -m cibuildwheel --output-dir wheelhouse

docs/working-examples.md

@@ -16,8 +16,8 @@ title: Working examples
 | [NCNN][]                          | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | ncnn is a high-performance neural network inference framework optimized for the mobile platform |
 | [Prophet][]                       | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Tool for producing high quality forecasts for time series data that has multiple seasonality with linear or non-linear growth. |
 | [MyPy][]                          | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | The compiled version of MyPy using MyPyC. |
-| [Kivy][]                          | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Open source UI framework written in Python, running on Windows, Linux, macOS, Android and iOS |
 | [duckdb][]                        | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | DuckDB is an in-process SQL OLAP Database Management System |
+| [Kivy][]                          | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Open source UI framework written in Python, running on Windows, Linux, macOS, Android and iOS |
 | [MemRay][]                        | ![github icon][] | ![linux icon][] | Memray is a memory profiler for Python |
 | [Triton][]                        | ![github icon][] | ![linux icon][] | Self hosted runners |
 | [uvloop][]                        | ![github icon][] | ![apple icon][] ![linux icon][] | Ultra fast asyncio event loop. |
@@ -44,8 +44,8 @@ title: Working examples
 | [Implicit][]                      | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Includes GPU support for linux wheels |
 | [vispy][]                         | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Main repository for Vispy |
 | [tinyobjloader][]                 | ![azurepipelines icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Tiny but powerful single file wavefront obj loader |
-| [coverage.py][]                   | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | The coverage tool for Python |
 | [CTranslate2][]                   | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Includes libraries from the [Intel oneAPI toolkit](https://www.intel.com/content/www/us/en/developer/tools/oneapi/base-toolkit.html) and CUDA kernels compiled for multiple GPU architectures. |
+| [coverage.py][]                   | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | The coverage tool for Python |
 | [PyCryptodome][]                  | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | A self-contained cryptographic library for Python |
 | [Line Profiler][]                 | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Line-by-line profiling for Python |
 | [PyYAML][]                        | ![github icon][] | ![apple icon][] | Canonical source repository for PyYAML |
@@ -79,8 +79,8 @@ title: Working examples
 | [tgcalls][]                       | ![github icon][] | ![apple icon][] ![windows icon][] | Python `pybind11` binding to Telegram's WebRTC library with third party dependencies like `OpenSSL`, `MozJPEG`, `FFmpeg`, etc. |
 | [python-snappy][]                 | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Python bindings for the snappy google library |
 | [pybind11 python_example][]       | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Example pybind11 module built with a Python-based build system |
-| [sourmash][]                      | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Quickly search, compare, and analyze genomic and metagenomic data sets. |
 | [abess][]                         | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | A fast best-subset selection library. It uses cibuildwheel to build a large project with C++ extensions. |
+| [sourmash][]                      | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Quickly search, compare, and analyze genomic and metagenomic data sets. |
 | [cyvcf2][]                        | ![github icon][] | ![apple icon][] ![linux icon][] | cython + htslib == fast VCF and BCF processing |
 | [matrixprofile][]                 | ![travisci icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | A Python 3 library making time series data mining tasks, utilizing matrix profile algorithms, accessible to everyone. |
 | [jq.py][]                         | ![travisci icon][] | ![apple icon][] ![linux icon][] | Python bindings for jq |
@@ -118,15 +118,15 @@ title: Working examples
 | [pybind11 cross build example][]  | ![github icon][] ![gitlab icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Same as pybind11 cmake_example but used to demo Linux ARM + Windows + macOS builds on GitLab |
 
 [scikit-learn]: https://github.com/scikit-learn/scikit-learn
-[pytorch-fairseq]: https://github.com/pytorch/fairseq
+[pytorch-fairseq]: https://github.com/facebookresearch/fairseq
 [NumPy]: https://github.com/numpy/numpy
 [Tornado]: https://github.com/tornadoweb/tornado
 [Matplotlib]: https://github.com/matplotlib/matplotlib
 [NCNN]: https://github.com/Tencent/ncnn
 [Prophet]: https://github.com/facebook/prophet
 [MyPy]: https://github.com/mypyc/mypy_mypyc-wheels
-[Kivy]: https://github.com/kivy/kivy
 [duckdb]: https://github.com/duckdb/duckdb
+[Kivy]: https://github.com/kivy/kivy
 [MemRay]: https://github.com/bloomberg/memray
 [Triton]: https://github.com/openai/triton
 [uvloop]: https://github.com/MagicStack/uvloop
@@ -141,11 +141,11 @@ title: Working examples
 [twisted-iocpsupport]: https://github.com/twisted/twisted-iocpsupport
 [PyOxidizer]: https://github.com/indygreg/PyOxidizer
 [cvxpy]: https://github.com/cvxpy/cvxpy
-[websockets]: https://github.com/aaugustin/websockets
+[websockets]: https://github.com/python-websockets/websockets
 [pedalboard]: https://github.com/spotify/pedalboard
 [River]: https://github.com/online-ml/river
 [UltraJSON]: https://github.com/ultrajson/ultrajson
-[OpenSpiel]: https://github.com/deepmind/open_spiel
+[OpenSpiel]: https://github.com/google-deepmind/open_spiel
 [aiortc]: https://github.com/aiortc/aiortc
 [Confluent client for Kafka]: https://github.com/confluentinc/confluent-kafka-python
 [Dependency Injector]: https://github.com/ets-labs/python-dependency-injector
@@ -153,8 +153,8 @@ title: Working examples
 [Implicit]: https://github.com/benfred/implicit
 [vispy]: https://github.com/vispy/vispy
 [tinyobjloader]: https://github.com/tinyobjloader/tinyobjloader
-[coverage.py]: https://github.com/nedbat/coveragepy
 [CTranslate2]: https://github.com/OpenNMT/CTranslate2
+[coverage.py]: https://github.com/nedbat/coveragepy
 [PyCryptodome]: https://github.com/Legrandin/pycryptodome
 [Line Profiler]: https://github.com/pyutils/line_profiler
 [PyYAML]: https://github.com/yaml/pyyaml
@@ -169,7 +169,7 @@ title: Working examples
 [aioquic]: https://github.com/aiortc/aioquic
 [Psycopg 3]: https://github.com/psycopg/psycopg
 [ruptures]: https://github.com/deepcharles/ruptures
-[OpenTimelineIO]: https://github.com/PixarAnimationStudios/OpenTimelineIO
+[OpenTimelineIO]: https://github.com/AcademySoftwareFoundation/OpenTimelineIO
 [PyTables]: https://github.com/PyTables/PyTables
 [Parselmouth]: https://github.com/YannickJadoul/Parselmouth
 [google neuroglancer]: https://github.com/google/neuroglancer
@@ -186,10 +186,10 @@ title: Working examples
 [dd-trace-py]: https://github.com/DataDog/dd-trace-py
 [python-rapidjson]: https://github.com/python-rapidjson/python-rapidjson
 [tgcalls]: https://github.com/MarshalX/tgcalls
-[python-snappy]: https://github.com/andrix/python-snappy
+[python-snappy]: https://github.com/intake/python-snappy
 [pybind11 python_example]: https://github.com/pybind/python_example
-[sourmash]: https://github.com/dib-lab/sourmash
 [abess]: https://github.com/abess-team/abess
+[sourmash]: https://github.com/sourmash-bio/sourmash
 [cyvcf2]: https://github.com/brentp/cyvcf2
 [matrixprofile]: https://github.com/matrix-profile-foundation/matrixprofile
 [jq.py]: https://github.com/mwilliamson/jq.py
@@ -203,7 +203,7 @@ title: Working examples
 [bx-python]: https://github.com/bxlab/bx-python
 [boost-histogram]: https://github.com/scikit-hep/boost-histogram
 [Python-WebRTC]: https://github.com/MarshalX/python-webrtc
-[power-grid-model]: https://github.com/alliander-opensource/power-grid-model
+[power-grid-model]: https://github.com/PowerGridModel/power-grid-model
 [pybase64]: https://github.com/mayeut/pybase64
 [fathon]: https://github.com/stfbnc/fathon
 [Imagecodecs (fork)]: https://github.com/czaki/imagecodecs_build

examples/appveyor-minimal.yml

@@ -12,7 +12,7 @@ stack: python 3.7
 init:
 - cmd: set PATH=C:\Python37;C:\Python37\Scripts;%PATH%
 
-install: python -m pip install cibuildwheel==2.18.0
+install: python -m pip install cibuildwheel==2.18.1
 
 build_script: python -m cibuildwheel --output-dir wheelhouse
 

examples/azure-pipelines-minimal.yml

@@ -6,7 +6,7 @@ jobs:
     - bash: |
         set -o errexit
         python3 -m pip install --upgrade pip
-        pip3 install cibuildwheel==2.18.0
+        pip3 install cibuildwheel==2.18.1
       displayName: Install dependencies
     - bash: cibuildwheel --output-dir wheelhouse .
       displayName: Build wheels
@@ -20,7 +20,7 @@ jobs:
     - bash: |
         set -o errexit
         python3 -m pip install --upgrade pip
-        python3 -m pip install cibuildwheel==2.18.0
+        python3 -m pip install cibuildwheel==2.18.1
       displayName: Install dependencies
     - bash: cibuildwheel --output-dir wheelhouse .
       displayName: Build wheels
@@ -34,7 +34,7 @@ jobs:
     - bash: |
         set -o errexit
         python -m pip install --upgrade pip
-        pip install cibuildwheel==2.18.0
+        pip install cibuildwheel==2.18.1
       displayName: Install dependencies
     - bash: cibuildwheel --output-dir wheelhouse .
       displayName: Build wheels

examples/circleci-minimal.yml

@@ -11,7 +11,7 @@ jobs:
       - run:
           name: Build the Linux wheels.
           command: |
-            pip3 install --user cibuildwheel==2.18.0
+            pip3 install --user cibuildwheel==2.18.1
             cibuildwheel --output-dir wheelhouse
       - store_artifacts:
           path: wheelhouse/
@@ -28,7 +28,7 @@ jobs:
       - run:
           name: Build the Linux aarch64 wheels.
           command: |
-            python3 -m pip install --user cibuildwheel==2.18.0
+            python3 -m pip install --user cibuildwheel==2.18.1
             python3 -m cibuildwheel --output-dir wheelhouse
       - store_artifacts:
           path: wheelhouse/
@@ -42,7 +42,7 @@ jobs:
       - run:
           name: Build the OS X wheels.
           command: |
-            pip3 install cibuildwheel==2.18.0
+            pip3 install cibuildwheel==2.18.1
             cibuildwheel --output-dir wheelhouse
       - store_artifacts:
           path: wheelhouse/

examples/cirrus-ci-intel-mac.yml

@@ -1,6 +1,6 @@
 build_and_store_wheels: &BUILD_AND_STORE_WHEELS
   install_cibuildwheel_script:
-    - python -m pip install cibuildwheel==2.18.0
+    - python -m pip install cibuildwheel==2.18.1
   run_cibuildwheel_script:
     - cibuildwheel
   wheels_artifacts:

examples/cirrus-ci-minimal.yml

@@ -1,6 +1,6 @@
 build_and_store_wheels: &BUILD_AND_STORE_WHEELS
   install_cibuildwheel_script:
-    - python -m pip install cibuildwheel==2.18.0
+    - python -m pip install cibuildwheel==2.18.1
   run_cibuildwheel_script:
     - cibuildwheel
   wheels_artifacts:

examples/github-deploy.yml

@@ -23,7 +23,7 @@ jobs:
       - uses: actions/checkout@v4
 
       - name: Build wheels
-        uses: pypa/cibuildwheel@v2.18.0
+        uses: pypa/cibuildwheel@v2.18.1
 
       - uses: actions/upload-artifact@v4
         with:

examples/github-minimal.yml

@@ -15,7 +15,7 @@ jobs:
       - uses: actions/checkout@v4
 
       - name: Build wheels
-        uses: pypa/cibuildwheel@v2.18.0
+        uses: pypa/cibuildwheel@v2.18.1
         # env:
         #   CIBW_SOME_OPTION: value
         #    ...

examples/github-with-qemu.yml

@@ -21,7 +21,7 @@ jobs:
           platforms: all
 
       - name: Build wheels
-        uses: pypa/cibuildwheel@v2.18.0
+        uses: pypa/cibuildwheel@v2.18.1
         env:
           # configure cibuildwheel to build native archs ('auto'), and some
           # emulated ones

examples/gitlab-minimal.yml

@@ -12,7 +12,7 @@ linux:
     DOCKER_TLS_CERTDIR: ""
   script:
     - curl -sSL https://get.docker.com/ | sh
-    - python -m pip install cibuildwheel==2.18.0
+    - python -m pip install cibuildwheel==2.18.1
     - cibuildwheel --output-dir wheelhouse
   artifacts:
     paths:
@@ -23,7 +23,7 @@ windows:
   before_script:
     - choco install python -y --version 3.8.6
     - choco install git.install -y
-    - py -m pip install cibuildwheel==2.18.0
+    - py -m pip install cibuildwheel==2.18.1
   script:
     - py -m cibuildwheel --output-dir wheelhouse --platform windows
   artifacts:

examples/gitlab-with-qemu.yml

@@ -14,7 +14,7 @@ linux:
     - curl -sSL https://get.docker.com/ | sh
     # Warning: This is extremely slow, be careful with how many wheels you build
     - docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
-    - python -m pip install cibuildwheel==2.18.0
+    - python -m pip install cibuildwheel==2.18.1
     # Assuming your CI runner's default architecture is x86_64...
     - cibuildwheel --output-dir wheelhouse --platform linux --archs aarch64
   artifacts:

examples/travis-ci-deploy.yml

@@ -20,7 +20,7 @@ jobs:
         - ln -s /c/Python38/python.exe /c/Python38/python3.exe
 
 install:
-  - python3 -m pip install cibuildwheel==2.18.0
+  - python3 -m pip install cibuildwheel==2.18.1
 
 script:
   # build the wheels, put them into './dist'

examples/travis-ci-minimal.yml

@@ -26,7 +26,7 @@ jobs:
         - ln -s /c/Python38/python.exe /c/Python38/python3.exe
 
 install:
-  - python3 -m pip install cibuildwheel==2.18.0
+  - python3 -m pip install cibuildwheel==2.18.1
 
 script:
   # build the wheels, put them into './wheelhouse'

examples/travis-ci-test-and-deploy.yml

@@ -54,7 +54,7 @@ jobs:
     - stage: deploy
       name: Build and deploy Linux wheels
       services: docker
-      install: python3 -m pip install cibuildwheel==2.18.0 twine
+      install: python3 -m pip install cibuildwheel==2.18.1 twine
       script: python3 -m cibuildwheel --output-dir wheelhouse
       after_success: python3 -m twine upload --skip-existing wheelhouse/*.whl
     # Deploy on windows
@@ -62,7 +62,7 @@ jobs:
       name: Build and deploy Windows wheels
       os: windows
       language: shell
-      install: python3 -m pip install cibuildwheel==2.18.0 twine
+      install: python3 -m pip install cibuildwheel==2.18.1 twine
       script: python3 -m cibuildwheel --output-dir wheelhouse
       after_success: python3 -m twine upload --skip-existing wheelhouse/*.whl
 

mkdocs.yml

@@ -49,3 +49,5 @@ plugins:
       module_name: docs/main
       j2_variable_start_string: «
       j2_variable_end_string: »
+      on_error_fail: true
+      on_undefined: strict

noxfile.py

@@ -4,15 +4,21 @@ import os
 import shutil
 import sys
 from pathlib import Path
+from typing import Any
 
 import nox
 
+nox.needs_version = ">=2024.4.15"
 nox.options.sessions = ["lint", "pylint", "check_manifest", "tests"]
+nox.options.default_venv_backend = "uv|virtualenv"
 
 DIR = Path(__file__).parent.resolve()
 
-if os.environ.get("CI", None):
-    nox.options.error_on_missing_interpreters = True
+
+def install_and_run(session: nox.Session, script: str, *args: str, **kwargs: Any) -> str | None:
+    deps = nox.project.load_toml(script)["dependencies"]
+    session.install(*deps)
+    return session.run("python", script, *args, **kwargs)
 
 
 @nox.session
@@ -20,11 +26,11 @@ def tests(session: nox.Session) -> None:
     """
     Run the unit and regular tests.
     """
-    unit_test_args = ["--run-docker"] if sys.platform.startswith("linux") else []
     session.install("-e.[test]")
     if session.posargs:
         session.run("pytest", *session.posargs)
     else:
+        unit_test_args = ["--run-docker"] if sys.platform.startswith("linux") else []
         session.run("pytest", "unit_test", *unit_test_args)
         session.run("pytest", "test", "-x", "--durations", "0", "--timeout=2400", "test")
 
@@ -44,8 +50,7 @@ def pylint(session: nox.Session) -> None:
     Run pylint.
     """
 
-    name = "cibuildwheel @ ." if getattr(session.virtualenv, "venv_backend", "") == "uv" else "."
-    session.install("pylint", name)
+    session.install("pylint>=3.2", "-e.")
     session.run("pylint", "cibuildwheel", *session.posargs)
 
 
@@ -65,7 +70,7 @@ def update_constraints(session: nox.Session) -> None:
     Update the dependencies inplace.
     """
 
-    if getattr(session.virtualenv, "venv_backend", "") != "uv":
+    if session.venv_backend != "uv":
         session.install("uv>=0.1.23")
 
     for minor_version in range(7, 14):
@@ -96,20 +101,19 @@ def update_pins(session: nox.Session) -> None:
     """
     Update the python, docker and virtualenv pins version inplace.
     """
-    session.install("-e", ".[bin]")
+    session.install("-e.[bin]")
     session.run("python", "bin/update_pythons.py", "--force")
     session.run("python", "bin/update_docker.py")
     session.run("python", "bin/update_virtualenv.py", "--force")
 
 
-@nox.session
+@nox.session(reuse_venv=True)
 def update_proj(session: nox.Session) -> None:
     """
     Update the README inplace.
     """
-    session.install("-e.[bin]")
-    session.run(
-        "python",
+    install_and_run(
+        session,
         "bin/projects.py",
         "docs/data/projects.yml",
         *session.posargs,
@@ -121,19 +125,26 @@ def generate_schema(session: nox.Session) -> None:
     """
     Generate the cibuildwheel.schema.json file.
     """
-    session.install("pyyaml")
-    output = session.run("python", "bin/generate_schema.py", silent=True)
+    output = install_and_run(session, "bin/generate_schema.py", silent=True)
     assert isinstance(output, str)
     DIR.joinpath("cibuildwheel/resources/cibuildwheel.schema.json").write_text(output)
 
 
-@nox.session(python="3.9")
+@nox.session(reuse_venv=True)
+def bump_version(session: nox.Session) -> None:
+    """
+    Bump cibuildwheel's version. Interactive.
+    """
+    install_and_run(session, "bin/bump_version.py")
+
+
+@nox.session(python="3.12")
 def docs(session: nox.Session) -> None:
     """
     Build the docs. Will serve unless --non-interactive
     """
     session.install("-e.[docs]")
-    session.run("mkdocs", "serve" if session.interactive else "build")
+    session.run("mkdocs", "serve" if session.interactive else "build", "--strict", *session.posargs)
 
 
 @nox.session

pyproject.toml

@@ -1,9 +1,94 @@
 [build-system]
-requires = [
-    "setuptools>=42",
-]
-build-backend = "setuptools.build_meta"
+requires = ["hatchling"]
+build-backend = "hatchling.build"
 
+[project]
+name = "cibuildwheel"
+version = "2.18.1"
+description = "Build Python wheels on CI with minimal configuration."
+readme = "README.md"
+license = "BSD-2-Clause"
+requires-python = ">=3.8"
+authors = [
+    { name = "Joe Rickerby", email = "joerick@mac.com" },
+]
+keywords = [
+    "appveyor",
+    "ci",
+    "linux",
+    "macos",
+    "packaging",
+    "pypi",
+    "travis",
+    "wheel",
+    "windows",
+]
+classifiers = [
+    "Development Status :: 5 - Production/Stable",
+    "Intended Audience :: Developers",
+    "License :: OSI Approved :: BSD License",
+    "Natural Language :: English",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3 :: Only",
+    "Programming Language :: Python :: 3.8",
+    "Programming Language :: Python :: 3.9",
+    "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python :: Implementation :: CPython",
+    "Topic :: Software Development :: Build Tools",
+]
+dependencies = [
+    "bashlex!=0.13",
+    "bracex",
+    "certifi",
+    "filelock",
+    "packaging>=20.9",
+    "platformdirs",
+    "tomli;python_version < '3.11'",
+    "typing-extensions>=4.1.0;python_version < '3.11'",
+]
+
+[project.optional-dependencies]
+bin = [
+    "click",
+    "packaging>=21.0",
+    "pip-tools",
+    "pygithub",
+    "pyyaml",
+    "requests",
+    "rich>=9.6",
+]
+dev = [
+    "cibuildwheel[test,bin]",
+]
+docs = [
+    "jinja2>=3.1.2",
+    "mkdocs-include-markdown-plugin==2.8.0",
+    "mkdocs-macros-plugin",
+    "mkdocs==1.3.1",
+    "pymdown-extensions",
+]
+test = [
+    "build",
+    "jinja2",
+    "pytest-timeout",
+    "pytest-xdist",
+    "pytest>=6",
+    "tomli_w",
+    "validate-pyproject",
+]
+
+[project.scripts]
+cibuildwheel = "cibuildwheel.__main__:main"
+
+[project.entry-points."validate_pyproject.tool_schema"]
+cibuildwheel = "cibuildwheel.schema:get_schema"
+
+[project.urls]
+Changelog = "https://github.com/pypa/cibuildwheel#changelog"
+Documentation = "https://cibuildwheel.pypa.io"
+Homepage = "https://github.com/pypa/cibuildwheel"
 
 [tool.pytest.ini_options]
 minversion = "6.0"
@@ -57,21 +142,6 @@ module = [
 ignore_missing_imports = true
 
 
-[tool.check-manifest]
-ignore = [
-    ".*",
-    ".circleci/**",
-    "test/**",
-    "unit_test/**",
-    "docs/**",
-    "examples/**",
-    "bin/**",
-    "*.yml",
-    "CI.md",  # TODO: can change test/test_ssl and remove this
-    "requirements-dev.txt",
-    "noxfile.py",
-]
-
 [tool.pylint]
 py-version = "3.8"
 jobs = "0"
@@ -162,6 +232,7 @@ flake8-unused-arguments.ignore-variadic-names = true
 [tool.ruff.lint.per-file-ignores]
 "unit_test/*" = ["PLC1901"]
 "cibuildwheel/_compat/**.py" = ["TID251"]
+"bin/*" = ["TID251"]
 
 [tool.repo-review]
 ignore = ["PC170", "PP303"]

setup.cfg

@@ -1,57 +0,0 @@
-[metadata]
-name = cibuildwheel
-version = 2.18.0
-description = Build Python wheels on CI with minimal configuration.
-long_description = file: README.md
-long_description_content_type = text/markdown
-url = https://github.com/pypa/cibuildwheel
-author = Joe Rickerby
-author_email = joerick@mac.com
-license = BSD-2-Clause
-license_files = LICENSE
-classifiers =
-    Development Status :: 5 - Production/Stable
-    Intended Audience :: Developers
-    License :: OSI Approved :: BSD License
-    Natural Language :: English
-    Programming Language :: Python :: 3
-    Programming Language :: Python :: 3 :: Only
-    Programming Language :: Python :: 3.8
-    Programming Language :: Python :: 3.9
-    Programming Language :: Python :: 3.10
-    Programming Language :: Python :: 3.11
-    Programming Language :: Python :: 3.12
-    Programming Language :: Python :: Implementation :: CPython
-    Topic :: Software Development :: Build Tools
-keywords = ci,wheel,packaging,pypi,travis,appveyor,macos,linux,windows
-project_urls =
-    Changelog=https://github.com/pypa/cibuildwheel#changelog
-    Documentation=https://cibuildwheel.pypa.io/
-
-[options]
-packages = find:
-install_requires =
-    bashlex!=0.13
-    bracex
-    certifi
-    filelock
-    packaging>=20.9
-    platformdirs
-    tomli;python_version < '3.11'
-    typing-extensions>=4.1.0;python_version < '3.11'
-python_requires = >=3.8
-include_package_data = True
-zip_safe = False
-
-[options.packages.find]
-include =
-    cibuildwheel
-
-[options.entry_points]
-console_scripts =
-    cibuildwheel = cibuildwheel.__main__:main
-validate_pyproject.tool_schema =
-    cibuildwheel = cibuildwheel.schema:get_schema
-
-[options.package_data]
-cibuildwheel = resources/*

setup.py

@@ -1,38 +0,0 @@
-from __future__ import annotations
-
-from setuptools import setup
-
-extras = {
-    "docs": [
-        "mkdocs-include-markdown-plugin==2.8.0",
-        "mkdocs==1.3.1",
-        "jinja2>=3.1.2",
-        "pymdown-extensions",
-        "mkdocs-macros-plugin",
-    ],
-    "test": [
-        "jinja2",
-        "pytest>=6",
-        "pytest-timeout",
-        "pytest-xdist",
-        "build",
-        "tomli_w",
-        "validate-pyproject",
-    ],
-    "bin": [
-        "click",
-        "pip-tools",
-        "pygithub",
-        "pyyaml",
-        "requests",
-        "rich>=9.6",
-        "packaging>=21.0",
-    ],
-}
-
-extras["dev"] = [
-    *extras["test"],
-    *extras["bin"],
-]
-
-setup(extras_require=extras)

test/test_abi_variants.py

@@ -13,9 +13,14 @@ build-backend = "setuptools.build_meta"
 limited_api_project = test_projects.new_c_project(
     setup_py_add=textwrap.dedent(
         r"""
+        import sysconfig
+
+        IS_CPYTHON = sys.implementation.name == "cpython"
+        Py_GIL_DISABLED = sysconfig.get_config_var("Py_GIL_DISABLED")
+        CAN_USE_ABI3 = IS_CPYTHON and not Py_GIL_DISABLED
         cmdclass = {}
         extension_kwargs = {}
-        if sys.version_info[:2] >= (3, 8):
+        if CAN_USE_ABI3 and sys.version_info[:2] >= (3, 8):
             from wheel.bdist_wheel import bdist_wheel as _bdist_wheel
 
             class bdist_wheel_abi3(_bdist_wheel):
@@ -47,7 +52,8 @@ def test_abi3(tmp_path):
     actual_wheels = utils.cibuildwheel_run(
         project_dir,
         add_env={
-            "CIBW_SKIP": "pp* ",  # PyPy does not have a Py_LIMITED_API equivalent
+            # free_threaded and PyPy do not have a Py_LIMITED_API equivalent, just build one of those
+            "CIBW_BUILD": "cp3?-* cp31?-* cp313t-* pp310-*"
         },
     )
 
@@ -55,7 +61,9 @@ def test_abi3(tmp_path):
     expected_wheels = [
         w.replace("cp38-cp38", "cp38-abi3")
         for w in utils.expected_wheels("spam", "0.1.0")
-        if "-pp" not in w and "-cp39" not in w and "-cp31" not in w
+        if ("-pp310" in w or "-pp" not in w)
+        and "-cp39" not in w
+        and ("-cp313t" in w or "-cp31" not in w)
     ]
     assert set(actual_wheels) == set(expected_wheels)
 
@@ -177,7 +185,7 @@ def test_abi_none(tmp_path, capfd):
             "CIBW_TEST_REQUIRES": "pytest",
             "CIBW_TEST_COMMAND": "pytest {project}/test",
             # limit the number of builds for test performance reasons
-            "CIBW_BUILD": "cp38-* cp310-* pp39-*",
+            "CIBW_BUILD": "cp38-* cp310-* cp313t-* pp310-*",
         },
     )
 

test/test_dependency_versions.py

@@ -111,7 +111,6 @@ def test_dependency_constraints_file(tmp_path, build_frontend_env):
             """
             pip=={pip}
             delocate=={delocate}
-            importlib-metadata<3,>=0.12; python_version < "3.8"
             """.format(**tool_versions)
         )
     )

test/test_macos_archs.py

@@ -202,13 +202,15 @@ def test_universal2_testing_on_arm64(tmp_path, capfd):
     assert set(actual_wheels) == set(expected_wheels)
 
 
-def test_cp38_arm64_testing(tmp_path, capfd):
+def test_cp38_arm64_testing(tmp_path, capfd, request):
     if utils.platform != "macos":
         pytest.skip("this test is only relevant to macos")
     if get_xcode_version() < (12, 2):
         pytest.skip("this test only works with Xcode 12.2 or greater")
     if platform.machine() != "arm64":
         pytest.skip("this test only works on arm64")
+    if request.config.getoption("--run-cp38-universal2"):
+        pytest.skip("--run-cp38-universal2 option skips this test")
 
     project_dir = tmp_path / "project"
     basic_project.generate(project_dir)

test/utils.py

@@ -37,6 +37,9 @@ def cibuildwheel_get_build_identifiers(project_path, env=None, *, prerelease_pyt
     cmd = [sys.executable, "-m", "cibuildwheel", "--print-build-identifiers", str(project_path)]
     if prerelease_pythons:
         cmd.append("--prerelease-pythons")
+    if env is None:
+        env = os.environ.copy()
+    env.setdefault("CIBW_FREE_THREADED_SUPPORT", "1")
 
     cmd_output = subprocess.run(
         cmd,
@@ -94,6 +97,8 @@ def cibuildwheel_run(
 
     _update_pip_cache_dir(env)
 
+    env.setdefault("CIBW_FREE_THREADED_SUPPORT", "1")
+
     with TemporaryDirectory() as tmp_output_dir:
         subprocess.run(
             [
@@ -147,6 +152,9 @@ def expected_wheels(
 
     if machine_arch is None:
         machine_arch = pm.machine()
+        if platform == "linux" and machine_arch.lower() == "arm64":
+            # we're running linux tests from macOS/Windows arm64, override platform
+            machine_arch = "aarch64"
 
     if manylinux_versions is None:
         if machine_arch == "x86_64":
@@ -173,6 +181,8 @@ def expected_wheels(
             "cp312-cp312",
             "cp313-cp313",
         ]
+        if platform != "macos":
+            python_abi_tags.append("cp313-cp313t")
 
         if machine_arch in ["x86_64", "AMD64", "x86", "aarch64"]:
             python_abi_tags += [

unit_test/build_selector_test.py

@@ -50,6 +50,7 @@ def test_build_filter_pre():
     assert build_selector("cp313-manylinux_x86_64")
     assert build_selector("cp37-win_amd64")
     assert build_selector("cp313-win_amd64")
+    assert not build_selector("cp313t-manylinux_x86_64")
 
 
 def test_skip():
@@ -144,6 +145,14 @@ def test_build_limited_python_patch():
     assert build_selector("cp37-manylinux_x86_64")
 
 
+def test_build_free_threaded_python():
+    build_selector = BuildSelector(
+        build_config="*", skip_config="", prerelease_pythons=True, free_threaded_support=True
+    )
+
+    assert build_selector("cp313t-manylinux_x86_64")
+
+
 def test_testing_selector():
     # local import to avoid pytest trying to collect this as a test class!
     from cibuildwheel.util import TestSelector

unit_test/linux_build_steps_test.py

@@ -5,13 +5,13 @@ from pathlib import Path
 from pprint import pprint
 
 import cibuildwheel.linux
-import cibuildwheel.oci_container
+from cibuildwheel.oci_container import OCIContainerEngineConfig
 from cibuildwheel.options import CommandLineArguments, Options
 
 
 def test_linux_container_split(tmp_path: Path, monkeypatch):
     """
-    Tests splitting linux builds by container image and before_all
+    Tests splitting linux builds by container image, container engine, and before_all
     """
 
     args = CommandLineArguments.defaults()
@@ -28,13 +28,17 @@ def test_linux_container_split(tmp_path: Path, monkeypatch):
                 archs = "x86_64 i686"
 
                 [[tool.cibuildwheel.overrides]]
-                select = "cp{38,39,310}-*"
+                select = "cp{37,38,39,310}-*"
                 manylinux-x86_64-image = "other_container_image"
                 manylinux-i686-image = "other_container_image"
 
                 [[tool.cibuildwheel.overrides]]
                 select = "cp39-*"
                 before-all = "echo 'a cp39-only command'"
+
+                [[tool.cibuildwheel.overrides]]
+                select = "cp310-*"
+                container-engine = "docker; create_args: --privileged"
             """
         )
     )
@@ -55,21 +59,35 @@ def test_linux_container_split(tmp_path: Path, monkeypatch):
     def before_alls(step):
         return [options.build_options(c.identifier).before_all for c in step.platform_configs]
 
+    def container_engines(step):
+        return [options.build_options(c.identifier).container_engine for c in step.platform_configs]
+
     pprint(build_steps)
 
+    default_container_engine = OCIContainerEngineConfig(name="docker")
+
     assert build_steps[0].container_image == "normal_container_image"
     assert identifiers(build_steps[0]) == [
         "cp36-manylinux_x86_64",
-        "cp37-manylinux_x86_64",
         "cp311-manylinux_x86_64",
         "cp312-manylinux_x86_64",
     ]
-    assert before_alls(build_steps[0]) == ["", "", "", ""]
+    assert before_alls(build_steps[0]) == [""] * 3
+    assert container_engines(build_steps[0]) == [default_container_engine] * 3
 
     assert build_steps[1].container_image == "other_container_image"
-    assert identifiers(build_steps[1]) == ["cp38-manylinux_x86_64", "cp310-manylinux_x86_64"]
-    assert before_alls(build_steps[1]) == ["", ""]
+    assert identifiers(build_steps[1]) == ["cp37-manylinux_x86_64", "cp38-manylinux_x86_64"]
+    assert before_alls(build_steps[1]) == [""] * 2
+    assert container_engines(build_steps[1]) == [default_container_engine] * 2
 
     assert build_steps[2].container_image == "other_container_image"
     assert identifiers(build_steps[2]) == ["cp39-manylinux_x86_64"]
     assert before_alls(build_steps[2]) == ["echo 'a cp39-only command'"]
+    assert container_engines(build_steps[2]) == [default_container_engine]
+
+    assert build_steps[3].container_image == "other_container_image"
+    assert identifiers(build_steps[3]) == ["cp310-manylinux_x86_64"]
+    assert before_alls(build_steps[3]) == [""]
+    assert container_engines(build_steps[3]) == [
+        OCIContainerEngineConfig(name="docker", create_args=("--privileged",))
+    ]

unit_test/oci_container_test.py

@@ -340,7 +340,7 @@ def test_create_args_volume(tmp_path: Path, container_engine):
     test_mount_dir.mkdir()
     (test_mount_dir / "test_file.txt").write_text("1234")
     container_engine = OCIContainerEngineConfig(
-        name="docker", create_args=[f"--volume={test_mount_dir}:/test_mount"]
+        name="docker", create_args=(f"--volume={test_mount_dir}:/test_mount",)
     )
 
     with OCIContainer(
@@ -356,37 +356,37 @@ def test_create_args_volume(tmp_path: Path, container_engine):
         (
             "docker",
             "docker",
-            [],
+            (),
         ),
         (
             "docker;create_args:",
             "docker",
-            [],
+            (),
         ),
         (
             "docker;create_args:--abc --def",
             "docker",
-            ["--abc", "--def"],
+            ("--abc", "--def"),
         ),
         (
             "docker; create_args: --abc --def",
             "docker",
-            ["--abc", "--def"],
+            ("--abc", "--def"),
         ),
         (
             "name:docker; create_args: --abc --def",
             "docker",
-            ["--abc", "--def"],
+            ("--abc", "--def"),
         ),
         (
             'docker; create_args: --some-option="value with spaces"',
             "docker",
-            ["--some-option=value with spaces"],
+            ("--some-option=value with spaces",),
         ),
         (
             'docker; create_args: --some-option="value; with; semicolons" --another-option',
             "docker",
-            ["--some-option=value; with; semicolons", "--another-option"],
+            ("--some-option=value; with; semicolons", "--another-option"),
         ),
     ],
 )

unit_test/options_test.py

@@ -206,49 +206,49 @@ def test_toml_environment_quoting(tmp_path: Path, toml_assignment, result_value)
         (
             'container-engine = "podman"',
             "podman",
-            [],
+            (),
             False,
         ),
         (
             'container-engine = {name = "podman"}',
             "podman",
-            [],
+            (),
             False,
         ),
         (
             'container-engine = "docker; create_args: --some-option"',
             "docker",
-            ["--some-option"],
+            ("--some-option",),
             False,
         ),
         (
             'container-engine = {name = "docker", create-args = ["--some-option"]}',
             "docker",
-            ["--some-option"],
+            ("--some-option",),
             False,
         ),
         (
             'container-engine = {name = "docker", create-args = ["--some-option", "value that contains spaces"]}',
             "docker",
-            ["--some-option", "value that contains spaces"],
+            ("--some-option", "value that contains spaces"),
             False,
         ),
         (
             'container-engine = {name = "docker", create-args = ["--some-option", "value;that;contains;semicolons"]}',
             "docker",
-            ["--some-option", "value;that;contains;semicolons"],
+            ("--some-option", "value;that;contains;semicolons"),
             False,
         ),
         (
             'container-engine = {name = "docker", disable-host-mount = true}',
             "docker",
-            [],
+            (),
             True,
         ),
         (
             'container-engine = {name = "docker", disable_host_mount = true}',
             "docker",
-            [],
+            (),
             True,
         ),
     ],
@@ -269,7 +269,7 @@ def test_container_engine_option(
     )
 
     options = Options(platform="linux", command_line_arguments=args, env={})
-    parsed_container_engine = options.globals.container_engine
+    parsed_container_engine = options.build_options(None).container_engine
 
     assert parsed_container_engine.name == result_name
     assert parsed_container_engine.create_args == result_create_args
@@ -415,3 +415,36 @@ def test_override_inherit_environment_with_references(tmp_path: Path):
     ) == {
         "PATH": "/opt/local/bin:/opt/bin:/usr/bin:/bin",
     }
+
+
+@pytest.mark.parametrize(
+    ("toml_assignment", "env", "expected_result"),
+    [
+        ("", {}, False),
+        ("free-threaded-support = true", {}, True),
+        ("free-threaded-support = false", {}, False),
+        ("", {"CIBW_FREE_THREADED_SUPPORT": "0"}, False),
+        ("", {"CIBW_FREE_THREADED_SUPPORT": "1"}, True),
+        ("free-threaded-support = false", {"CIBW_FREE_THREADED_SUPPORT": "1"}, True),
+        ("free-threaded-support = true", {"CIBW_FREE_THREADED_SUPPORT": "0"}, False),
+        ("free-threaded-support = true", {"CIBW_FREE_THREADED_SUPPORT": ""}, True),
+        ("free-threaded-support = false", {"CIBW_FREE_THREADED_SUPPORT": ""}, False),
+    ],
+)
+def test_free_threaded_support(
+    tmp_path: Path, toml_assignment: str, env: dict[str, str], expected_result: bool
+):
+    args = CommandLineArguments.defaults()
+    args.package_dir = tmp_path
+
+    pyproject_toml: Path = tmp_path / "pyproject.toml"
+    pyproject_toml.write_text(
+        textwrap.dedent(
+            f"""\
+            [tool.cibuildwheel]
+            {toml_assignment}
+            """
+        )
+    )
+    options = Options(platform="linux", command_line_arguments=args, env=env)
+    assert options.globals.build_selector.free_threaded_support is expected_result

unit_test/validate_schema_test.py

@@ -20,11 +20,39 @@ def test_validate_default_schema():
     assert validator(example) is not None
 
 
-def test_validate_bad_container_engine():
+def test_validate_container_engine():
+    """
+    This test checks container engine can be overridden - it used to be a
+    global option but is now a build option.
+    """
+
     example = tomllib.loads(
         """
+        [tool.cibuildwheel]
+        container-engine = "docker"
+
         [tool.cibuildwheel.linux]
         container-engine = "docker"
+
+        [[tool.cibuildwheel.overrides]]
+        select = "*_x86_64"
+        container-engine = "docker; create_args: --platform linux/arm64/v8"
+        """
+    )
+
+    validator = validate_pyproject.api.Validator()
+    assert validator(example) is not None
+
+
+@pytest.mark.parametrize("platform", ["macos", "windows"])
+def test_validate_bad_container_engine(platform: str):
+    """
+    container-engine is not a valid option for macos or windows
+    """
+    example = tomllib.loads(
+        f"""
+        [tool.cibuildwheel.{platform}]
+        container-engine = "docker"
         """
     )