Bump version: v2.0.1

Update dependencies (#771 )
Co-authored-by: mayeut <mayeut@users.noreply.github.com>
2021-07-25 14:39:54 +01:00 · 2021-07-25 12:36:10 +02:00 · 2021-07-20 18:58:20 +01:00 · 2021-07-19 23:23:06 +02:00 · 2021-07-19 21:15:24 +00:00 · 2021-07-19 18:36:31 +01:00
90 changed files with 2656 additions and 24084 deletions
@@ -3,7 +3,7 @@ version: 2
 jobs:
  osx-python3.6:
    macos:
-      xcode: 9.4.1
+      xcode: 12.5.1
    environment:
      PYTHON: python3
    steps:
@@ -1,7 +0,0 @@
-# config file for https://github.com/bobvanderlinden/probot-auto-merge
-
-# no approvals required, just the label is enough
-minApprovals: {}
-
-requiredLabels:
- merge when green
@@ -0,0 +1,10 @@
+version: 2
+updates:
+  # Maintain dependencies for GitHub Actions
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    ignore:
+      - dependency-name: "actions/*"
+        update-types: ["version-update:semver-minor", "version-update:semver-patch"]
@@ -3,8 +3,7 @@ name: Test
 on:
  push:
    branches:
-      - master
-      - 1.x
+      - main
  pull_request:
    paths-ignore:
      - 'docs/**'
@@ -18,7 +17,7 @@ jobs:
    steps:
    - uses: actions/checkout@v2
    - uses: actions/setup-python@v2
-    - uses: pre-commit/action@v2.0.0
+    - uses: pre-commit/action@v2.0.3

  test:
    name: Test cibuildwheel on ${{ matrix.os }}
@@ -38,7 +37,7 @@ jobs:

    - name: Install dependencies
      run: |
-        python -m pip install -e ".[dev]"
+        python -m pip install ".[test]"

    - name: Sample build
      if: "contains(github.event.pull_request.labels.*.name, 'CI: Sample build')"
@@ -71,7 +70,7 @@ jobs:
    - uses: actions/setup-python@v2
    - name: Install dependencies
      run: |
-        python -m pip install -r requirements-dev.txt
+        python -m pip install ".[test]"

    - name: Set up QEMU
      id: qemu
@@ -11,19 +11,25 @@ jobs:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v2
-    - uses: actions/setup-python@v2
-      name: Install Python 3.9
-      with:
-        python-version: 3.9
-        architecture: x64
-    - name: Install dependencies
-      run: python -m pip install ".[dev]"
+    - uses: excitedleigh/setup-nox@v2.0.0
+
    - name: "Run update: dependencies"
-      run: python ./bin/update_dependencies.py
+      run: nox --force-color -s update_constraints
    - name: "Run update: python configs"
-      run: python ./bin/update_pythons.py --force
+      run: nox --force-color -s update_pins
+    - name: "Run update: docs user projects"
+      run: nox --force-color -s update_proj -- --auth=${{ secrets.GITHUB_TOKEN }}
+
+    # we use this step to grab a Github App auth token, so that PRs generated by this workflow
+    # run the GHA tests.
+    - uses: tibdex/github-app-token@v1
+      id: generate-token
+      with:
+        app_id: ${{ secrets.CIBUILDWHEEL_BOT_APP_ID }}
+        private_key: ${{ secrets.CIBUILDWHEEL_BOT_APP_PRIVATE_KEY }}
+
    - name: Create Pull Request
-      if: github.ref == 'refs/heads/master' && github.repository == 'pypa/cibuildwheel'
+      if: github.ref == 'refs/heads/main' && github.repository == 'pypa/cibuildwheel'
      uses: peter-evans/create-pull-request@v3
      with:
        commit-message: Update dependencies
@@ -33,4 +39,5 @@ jobs:

          PR generated by "Update dependencies" [workflow](https://github.com/${{github.repository}}/actions/runs/${{github.run_id}}).
        branch: update-dependencies-pr
+        token: ${{ steps.generate-token.outputs.token }}
        delete-branch: true
@@ -114,3 +114,6 @@ site/

 # Virtual environments
 venv*
+
+# PyCharm
+.idea/
@@ -1,7 +1,7 @@
 repos:

 - repo: https://github.com/pre-commit/pre-commit-hooks
-  rev: v3.4.0
+  rev: v4.0.1
  hooks:
  - id: check-case-conflict
  - id: check-merge-conflict
@@ -13,37 +13,8 @@ repos:
  - id: mixed-line-ending
  - id: trailing-whitespace

- repo: https://github.com/PyCQA/isort
-  rev: 5.8.0
-  hooks:
-  - id: isort
-
- repo: https://github.com/psf/black
-  rev: 21.4b2
-  hooks:
-  - id: black
-
- repo: https://github.com/asottile/setup-cfg-fmt
-  rev: v1.17.0
-  hooks:
-  - id: setup-cfg-fmt
-    stages: [manual]
-
- repo: https://github.com/pre-commit/mirrors-mypy
-  rev: v0.812
-  hooks:
-  - id: mypy
-    exclude: ^(bin/|cibuildwheel/resources/).*py$
-    additional_dependencies: [packaging]
-    args: ["--python-version=3.6", "--ignore-missing-imports", "--scripts-are-modules"]
-  - id: mypy
-    name: mypy 3.7+ on bin/
-    files: ^bin/.*py$
-    additional_dependencies: [packaging]
-    args: ["--python-version=3.7", "--ignore-missing-imports", "--scripts-are-modules"]
-
 - repo: https://github.com/asottile/pyupgrade
-  rev: v2.14.0
+  rev: v2.21.2
  hooks:
  - id: pyupgrade
    name: PyUpgrade 3.6+
@@ -54,8 +25,48 @@ repos:
    exclude: ^(cibuildwheel|unit_test|test)/
    args: ["--py37-plus"]

+- repo: https://github.com/PyCQA/isort
+  rev: 5.9.2
+  hooks:
+  - id: isort
+
+- repo: https://github.com/psf/black
+  rev: 21.7b0
+  hooks:
+  - id: black
+
+- repo: https://github.com/asottile/setup-cfg-fmt
+  rev: v1.17.0
+  hooks:
+  - id: setup-cfg-fmt
+    stages: [manual]
+
+- repo: https://github.com/pre-commit/mirrors-mypy
+  rev: v0.910
+  hooks:
+  - id: mypy
+    exclude: ^(bin|cibuildwheel/resources|docs)/.*py$
+    args: ["--python-version=3.6", "--scripts-are-modules"]
+    additional_dependencies:
+      - packaging
+      - types-jinja2
+      - types-certifi
+      - types-toml
+  - id: mypy
+    name: mypy 3.7+ on bin/
+    files: ^((bin|docs)/.*py|noxfile.py)$
+    args: ["--python-version=3.7", "--scripts-are-modules"]
+    additional_dependencies:
+      - packaging>=21.0
+      - rich
+      - types-jinja2
+      - types-pyyaml
+      - types-click
+      - types-requests
+      - types-toml
+
 - repo: https://github.com/PyCQA/flake8
-  rev: 3.9.1
+  rev: 3.9.2
  hooks:
  - id: flake8
    exclude: cibuildwheel/resources/
@@ -66,6 +77,12 @@ repos:
  - id: disallow-caps
    name: Disallow improper capitalization
    language: pygrep
-    entry: PyBind|Numpy|Cmake|Github
+    entry: PyBind|Numpy|Cmake|Github|PyTest
    types:
    - markdown
+
+- repo: https://github.com/codespell-project/codespell
+  rev: v2.1.0
+  hooks:
+  - id: codespell
+    args: ["-L", "sur"]
@@ -4,7 +4,7 @@ language: python

 branches:
  only:
-  - master
+  - main

 jobs:
  include:
@@ -16,13 +16,16 @@ jobs:
    - name: Linux | arm64 | Python 3.6
      python: 3.6
      services: docker
-      arch: arm64
+      arch: arm64-graviton2
+      group: edge
+      virt: vm
      env: PYTHON=python

    - name: Linux | ppc64le | Python 3.6
      python: 3.6
      services: docker
      arch: ppc64le
+      allow_failure: True
      env:
        - PYTHON=python
        # skip test_manylinuxXXXX_only, it uses too much disk space
@@ -1,12 +1,11 @@
 This is a summary of the Python versions and platforms covered by the different CI platforms:

-|          | 3.6                          | 3.7                                      | 3.8              |
-|----------|------------------------------|------------------------------------------|------------------|
-| Linux    | Travis CI / CircleCI         | AppVeyor² / GitHub Actions               | Azure Pipelines  |
-| macOS    | CircleCI                     | AppVeyor² / Travis CI¹ / GitHub Actions  | Azure Pipelines  |
-| Windows  | Travis CI / Azure Pipelines  | AppVeyor² / GitHub Actions               | Azure Pipelines  |
+|          | 3.6                          | 3.7                         | 3.8              |
+|----------|------------------------------|-----------------------------|------------------|
+| Linux    | Travis CI / CircleCI         | AppVeyor¹ / GitHub Actions  | Azure Pipelines  |
+| macOS    | CircleCI                     | AppVeyor¹ / GitHub Actions  | Azure Pipelines  |
+| Windows  | Travis CI / Azure Pipelines  | AppVeyor¹ / GitHub Actions  | Azure Pipelines  |

-> ¹ Python version not really pinned, but dependent on the (default) version of image used.
-> ² AppVeyor only runs the "basic" test to reduce load.
+> ¹ AppVeyor only runs the "basic" test to reduce load.

 Non-x86 architectures are covered on Travis CI using Python 3.6.
@@ -22,7 +22,3 @@ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-
-Get-pip and Pip (bundled in cibuildwheel/resources) are licensed under the MIT
-license. See https://github.com/pypa/get-pip/blob/master/LICENSE.txt
@@ -4,10 +4,10 @@ cibuildwheel
 [![PyPI](https://img.shields.io/pypi/v/cibuildwheel.svg)](https://pypi.python.org/pypi/cibuildwheel)
 [![Documentation Status](https://readthedocs.org/projects/cibuildwheel/badge/?version=stable)](https://cibuildwheel.readthedocs.io/en/stable/?badge=stable)
 [![Actions Status](https://github.com/pypa/cibuildwheel/workflows/Test/badge.svg)](https://github.com/pypa/cibuildwheel/actions)
-[![Travis Status](https://img.shields.io/travis/com/pypa/cibuildwheel/master?logo=travis)](https://travis-ci.com/pypa/cibuildwheel)
-[![Appveyor status](https://ci.appveyor.com/api/projects/status/gt3vwl88yt0y3hur/branch/master?svg=true)](https://ci.appveyor.com/project/joerick/cibuildwheel/branch/master)
-[![CircleCI Status](https://img.shields.io/circleci/build/gh/pypa/cibuildwheel/master?logo=circleci)](https://circleci.com/gh/pypa/cibuildwheel)
-[![Azure Status](https://dev.azure.com/joerick0429/cibuildwheel/_apis/build/status/pypa.cibuildwheel?branchName=master)](https://dev.azure.com/joerick0429/cibuildwheel/_build/latest?definitionId=4&branchName=master)
+[![Travis Status](https://img.shields.io/travis/com/pypa/cibuildwheel/main?logo=travis)](https://travis-ci.com/pypa/cibuildwheel)
+[![Appveyor status](https://ci.appveyor.com/api/projects/status/gt3vwl88yt0y3hur/branch/main?svg=true)](https://ci.appveyor.com/project/joerick/cibuildwheel/branch/main)
+[![CircleCI Status](https://img.shields.io/circleci/build/gh/pypa/cibuildwheel/main?logo=circleci)](https://circleci.com/gh/pypa/cibuildwheel)
+[![Azure Status](https://dev.azure.com/joerick0429/cibuildwheel/_apis/build/status/pypa.cibuildwheel?branchName=main)](https://dev.azure.com/joerick0429/cibuildwheel/_build/latest?definitionId=4&branchName=main)


 [Documentation](https://cibuildwheel.readthedocs.org)
@@ -23,24 +23,23 @@ What does it do?
 ----------------

 |   | macOS Intel | macOS Apple Silicon | Windows 64bit | Windows 32bit | manylinux x86_64 | manylinux i686 | manylinux aarch64 | manylinux ppc64le | manylinux s390x |
-|---|---|---|---|---|---|---|---|---|---|
-| CPython 2.7     | ✅ |   | ✅¹ | ✅¹ | ✅ | ✅ |    |    |   |
-| CPython 3.5     | ✅ |   | ✅  | ✅  | ✅ | ✅ | ✅ | ✅ | ✅ |
-| CPython 3.6     | ✅ |   | ✅  | ✅  | ✅ | ✅ | ✅ | ✅ | ✅ |
-| CPython 3.7     | ✅ |   | ✅  | ✅  | ✅ | ✅ | ✅ | ✅ | ✅ |
-| CPython 3.8     | ✅ |   | ✅  | ✅  | ✅ | ✅ | ✅ | ✅ | ✅ |
-| CPython 3.9     | ✅ | ✅ | ✅  | ✅  | ✅ | ✅ | ✅ | ✅ | ✅ |
-| PyPy 2.7 v7.3.3 | ✅ |    |    | ✅  | ✅ |    |    |    |   |
-| PyPy 3.6 v7.3.3 | ✅ |    |    | ✅  | ✅ |    |    |    |   |
-| PyPy 3.7 (beta) v7.3.3 | ✅ | |  | ✅  | ✅ |    |    |   |    |
+|---------------|----|-----|-----|-----|----|-----|----|-----|-----|
+| CPython 3.6   | ✅ | N/A | ✅  | ✅  | ✅ | ✅  | ✅ | ✅  | ✅  |
+| CPython 3.7   | ✅ | N/A | ✅  | ✅  | ✅ | ✅  | ✅ | ✅  | ✅  |
+| CPython 3.8   | ✅ | ✅  | ✅  | ✅  | ✅ | ✅  | ✅ | ✅  | ✅  |
+| CPython 3.9   | ✅ | ✅  | ✅  | ✅  | ✅ | ✅  | ✅ | ✅  | ✅  |
+| CPython 3.10¹ | ✅ | ✅  | ✅  | ✅  | ✅ | ✅  | ✅ | ✅  | ✅  |
+| PyPy 3.7 v7.3 | ✅ | N/A | ✅  | N/A | ✅ | ✅  | ✅ | N/A | N/A |

-<sup>¹ Only using a workaround with a newer compiler; Microsoft removed the 2008 compiler for Python 2.7 in April 2021.</sup><br>
+<sup>¹ Available as a prerelease under a [flag](https://cibuildwheel.readthedocs.io/en/stable/options/#prerelease-pythons)</sup><br>

 - Builds manylinux, macOS 10.9+, and Windows wheels for CPython and PyPy
 - Works on GitHub Actions, Azure Pipelines, Travis CI, AppVeyor, CircleCI, and GitLab CI
 - Bundles shared library dependencies on Linux and macOS through [auditwheel](https://github.com/pypa/auditwheel) and [delocate](https://github.com/matthew-brett/delocate)
 - Runs your library's tests against the wheel-installed version of your library

+See the [cibuildwheel 1 documentation](https://cibuildwheel.readthedocs.io/en/1.x/) if you need to build unsupported versions of Python, such as Python 2.
+
 Usage
 -----

@@ -48,9 +47,9 @@ Usage

 |                 | Linux | macOS | Windows | Linux ARM |
 |-----------------|-------|-------|---------|--------------|
-| GitHub Actions  | ✅    | ✅    | ✅      | ✅¹           |
+| GitHub Actions  | ✅    | ✅    | ✅      | ✅¹          |
 | Azure Pipelines | ✅    | ✅    | ✅      |              |
-| Travis CI       | ✅    | ✅    | ✅      | ✅           |
+| Travis CI       | ✅    |       | ✅      | ✅           |
 | AppVeyor        | ✅    | ✅    | ✅      |              |
 | CircleCI        | ✅    | ✅    |         |              |
 | Gitlab CI       | ✅    |       |         |              |
@@ -86,7 +85,7 @@ jobs:
      - uses: actions/setup-python@v2

      - name: Install cibuildwheel
-        run: python -m pip install cibuildwheel==1.11.1.post1
+        run: python -m pip install cibuildwheel==2.0.1

      - name: Build wheels
        run: python -m cibuildwheel --output-dir wheelhouse
@@ -99,7 +98,7 @@ jobs:
          path: ./wheelhouse/*.whl
 ```

-For more information, including building on Python 2, PyPI deployment, and the use of other CI services or the dedicated GitHub Action, check out the [documentation](https://cibuildwheel.readthedocs.org) and the [examples](https://github.com/pypa/cibuildwheel/tree/master/examples).
+For more information, including PyPI deployment, and the use of other CI services or the dedicated GitHub Action, check out the [documentation](https://cibuildwheel.readthedocs.org) and the [examples](https://github.com/pypa/cibuildwheel/tree/main/examples).

 Options
 -------
@@ -108,13 +107,15 @@ Options
 |---|--------|-------------|
 | **Build selection** | [`CIBW_PLATFORM`](https://cibuildwheel.readthedocs.io/en/stable/options/#platform)  | Override the auto-detected target platform |
 |   | [`CIBW_BUILD`](https://cibuildwheel.readthedocs.io/en/stable/options/#build-skip)  <br> [`CIBW_SKIP`](https://cibuildwheel.readthedocs.io/en/stable/options/#build-skip)  | Choose the Python versions to build |
-|   | [`CIBW_ARCHS`](https://cibuildwheel.readthedocs.io/en/stable/options/#archs)  | Change the architectures built on your machine by default |
+|   | [`CIBW_ARCHS`](https://cibuildwheel.readthedocs.io/en/stable/options/#archs)  | Change the architectures built on your machine by default. |
 |   | [`CIBW_PROJECT_REQUIRES_PYTHON`](https://cibuildwheel.readthedocs.io/en/stable/options/#requires-python)  | Manually set the Python compatibility of your project |
-| **Build customization** | [`CIBW_ENVIRONMENT`](https://cibuildwheel.readthedocs.io/en/stable/options/#environment)  | Set environment variables needed during the build |
+|   | [`CIBW_PRERELEASE_PYTHONS`](https://cibuildwheel.readthedocs.io/en/stable/options/#prerelease-pythons)  | Enable building with pre-release versions of Python |
+| **Build customization** | [`CIBW_BUILD_FRONTEND`](https://cibuildwheel.readthedocs.io/en/stable/options/#build-frontend)  | Set the tool to use to build, either "pip" (default for now) or "build" |
+|   | [`CIBW_ENVIRONMENT`](https://cibuildwheel.readthedocs.io/en/stable/options/#environment)  | Set environment variables needed during the build |
 |   | [`CIBW_BEFORE_ALL`](https://cibuildwheel.readthedocs.io/en/stable/options/#before-all)  | Execute a shell command on the build system before any wheels are built. |
 |   | [`CIBW_BEFORE_BUILD`](https://cibuildwheel.readthedocs.io/en/stable/options/#before-build)  | Execute a shell command preparing each wheel's build |
 |   | [`CIBW_REPAIR_WHEEL_COMMAND`](https://cibuildwheel.readthedocs.io/en/stable/options/#repair-wheel-command)  | Execute a shell command to repair each (non-pure Python) built wheel |
-|   | [`CIBW_MANYLINUX_X86_64_IMAGE`](https://cibuildwheel.readthedocs.io/en/stable/options/#manylinux-image)  <br> [`CIBW_MANYLINUX_I686_IMAGE`](https://cibuildwheel.readthedocs.io/en/stable/options/#manylinux-image)  <br> [`CIBW_MANYLINUX_PYPY_X86_64_IMAGE`](https://cibuildwheel.readthedocs.io/en/stable/options/#manylinux-image)  <br> [`CIBW_MANYLINUX_AARCH64_IMAGE`](https://cibuildwheel.readthedocs.io/en/stable/options/#manylinux-image)  <br> [`CIBW_MANYLINUX_PPC64LE_IMAGE`](https://cibuildwheel.readthedocs.io/en/stable/options/#manylinux-image)  <br> [`CIBW_MANYLINUX_S390X_IMAGE`](https://cibuildwheel.readthedocs.io/en/stable/options/#manylinux-image)  | Specify alternative manylinux docker images |
+|   | [`CIBW_MANYLINUX_*_IMAGE`](https://cibuildwheel.readthedocs.io/en/stable/options/#manylinux-image)  | Specify alternative manylinux Docker images |
 |   | [`CIBW_DEPENDENCY_VERSIONS`](https://cibuildwheel.readthedocs.io/en/stable/options/#dependency-versions)  | Specify how cibuildwheel controls the versions of the tools it uses |
 | **Testing** | [`CIBW_TEST_COMMAND`](https://cibuildwheel.readthedocs.io/en/stable/options/#test-command)  | Execute a shell command to test each built wheel |
 |   | [`CIBW_BEFORE_TEST`](https://cibuildwheel.readthedocs.io/en/stable/options/#before-test)  | Execute a shell command before testing each wheel |
@@ -123,6 +124,7 @@ Options
 |   | [`CIBW_TEST_SKIP`](https://cibuildwheel.readthedocs.io/en/stable/options/#test-skip)  | Skip running tests on some builds |
 | **Other** | [`CIBW_BUILD_VERBOSITY`](https://cibuildwheel.readthedocs.io/en/stable/options/#build-verbosity)  | Increase/decrease the output of pip wheel |

+These options can be specified in a pyproject.toml file, as well; see [configuration](https://cibuildwheel.readthedocs.io/en/stable/options/#configuration).

 Working examples
 ----------------
@@ -143,6 +145,7 @@ Here are some repos that use cibuildwheel.
 | [psutil][]                        | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Cross-platform lib for process and system monitoring in Python |
 | [scikit-image][]                  | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Image processing library. Uses cibuildwheel to build and test a project that uses Cython with platform-native code.  |
 | [twisted-iocpsupport][]           | ![github icon][] | ![windows icon][] | A submodule of Twisted that hooks into native C APIs using Cython. |
+| [cmake][]                         | ![github icon][] ![travisci icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Multitagged binary builds for all supported platforms, using cibw 2 config configuration. |
 | [websockets][]                    | ![travisci icon][] | ![apple icon][] ![linux icon][] | Library for building WebSocket servers and clients. Mostly written in Python, with a small C 'speedups' extension module.  |
 | [pyzmq][]                         | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Python bindings for zeromq, the networking library. Uses Cython and CFFI.  |
 | [aiortc][]                        | ![github icon][] | ![apple icon][] ![linux icon][] | WebRTC and ORTC implementation for Python using asyncio. |
@@ -156,8 +159,8 @@ Here are some repos that use cibuildwheel.
 | [ruptures][]                      | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Extensive Cython + NumPy [pyproject.toml](https://github.com/deepcharles/ruptures/blob/master/pyproject.toml) example. |
 | [aioquic][]                       | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | QUIC and HTTP/3 implementation in Python |
 | [pikepdf][]                       | ![azurepipelines icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | A Python library for reading and writing PDF, powered by qpdf |
-| [DeepForest][]                    | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | An Efficient, Scalable and Optimized Python Framework for Deep Forest (2021.2.1) |
 | [google neuroglancer][]           | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | WebGL-based viewer for volumetric data |
+| [DeepForest][]                    | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | An Efficient, Scalable and Optimized Python Framework for Deep Forest (2021.2.1) |
 | [AutoPy][]                        | ![travisci icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Includes a Windows Travis build. |
 | [Parselmouth][]                   | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | A Python interface to the Praat software package, using pybind11, C++17 and CMake, with the core Praat static library built only once and shared between wheels. |
 | [python-rapidjson][]              | ![travisci icon][] ![gitlab icon][] ![appveyor icon][] | ![windows icon][] ![linux icon][] | Python wrapper around rapidjson |
@@ -169,31 +172,32 @@ Here are some repos that use cibuildwheel.
 | [KDEpy][]                         | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Kernel Density Estimation in Python |
 | [cyvcf2][]                        | ![github icon][] | ![apple icon][] ![linux icon][] | cython + htslib == fast VCF and BCF processing |
 | [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. |
 | [dd-trace-py][]                   | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Uses custom alternate arch emulation on GitHub |
-| [iminuit][]                       | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Jupyter-friendly Python interface for C++ MINUIT2 |
+| [sourmash][]                      | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Quickly search, compare, and analyze genomic and metagenomic data sets. |
 | [time-machine][]                  | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Time mocking library using only the CPython C API. |
-| [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. |
+| [iminuit][]                       | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Jupyter-friendly Python interface for C++ MINUIT2 |
 | [CTranslate2][]                   | ![github icon][] | ![apple icon][] ![linux icon][] | Includes libraries from the [Intel oneAPI toolkit](https://software.intel.com/content/www/us/en/develop/tools/oneapi/base-toolkit.html). The Linux wheels also include CUDA libraries for GPU execution. |
+| [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 |
 | [Tokenizer][]                     | ![github icon][] ![travisci icon][] | ![apple icon][] ![linux icon][] | Fast and customizable text tokenization library with BPE and SentencePiece support |
 | [PyGLM][]                         | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Fast OpenGL Mathematics (GLM) for Python |
 | [bx-python][]                     | ![travisci icon][] | ![apple icon][] ![linux icon][] | A library that includes Cython extensions. |
-| [boost-histogram][]               | ![github icon][] ![travisci icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Supports full range of wheels, including PyPy and alternate archs. |
 | [iDynTree][]                      | ![github icon][] | ![linux icon][] | Uses manylinux_2_24 |
-| [TgCrypto][]                      | ![travisci icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Includes a Windows Travis build. |
+| [boost-histogram][]               | ![github icon][] ![travisci icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Supports full range of wheels, including PyPy and alternate archs. |
 | [pybase64][]                      | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Fast Base64 encoding/decoding in Python |
+| [TgCrypto][]                      | ![travisci icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Includes a Windows Travis build. |
 | [etebase-py][]                    | ![travisci icon][] | ![linux icon][] | Python bindings to a Rust library using `setuptools-rust`, and `sccache` for improved speed. |
+| [fathon][]                        | ![travisci icon][] | ![apple icon][] ![linux icon][] | python package for DFA (Detrended Fluctuation Analysis) and related algorithms |
 | [pyjet][]                         | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | The interface between FastJet and NumPy |
 | [numpythia][]                     | ![github icon][] | ![apple icon][] ![linux icon][] | The interface between PYTHIA and NumPy |
-| [fathon][]                        | ![travisci icon][] | ![apple icon][] ![linux icon][] | python package for DFA (Detrended Fluctuation Analysis) and related algorithms |
 | [polaroid][]                      | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Full range of wheels for setuptools rust, with auto release and PyPI deploy. |
+| [ninja][]                         | ![github icon][] ![travisci icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Multitagged binary builds for all supported platforms, using cibw 2 config configuration. |
 | [GSD][]                           | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Cython and NumPy project with 64-bit wheels. |
 | [pybind11 scikit_build_example][] | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | An example combining scikit-build and pybind11 |
+| [Imagecodecs (fork)][]            | ![azurepipelines icon][] | ![apple icon][] ![linux icon][] | Over 20 external dependencies in compiled libraries, custom docker image, `libomp`, `openblas` and `install_name_tool` for macOS. |
 | [pyinstrument_cext][]             | ![travisci icon][] ![appveyor icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | A simple C extension, without external dependencies |
 | [xmlstarlet][]                    | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Python 3.6+ CFFI bindings with true MSVC build. |
 | [CorrectionLib][]                 | ![github icon][] | ![apple icon][] ![linux icon][] | Structured JSON powered correction library for HEP, designed for the CMS experiment at CERN. |
-| [Imagecodecs (fork)][]            | ![azurepipelines icon][] | ![apple icon][] ![linux icon][] | Over 20 external dependencies in compiled libraries, custom docker image, `libomp`, `openblas` and `install_name_tool` for macOS. |
 | [SiPM][]                          | ![github icon][] | ![apple icon][] ![linux icon][] | High performance library for SiPM detectors simulation using C++17, OpenMP and AVX2 intrinsics. |

 [scikit-learn]: https://github.com/scikit-learn/scikit-learn
@@ -202,6 +206,7 @@ Here are some repos that use cibuildwheel.
 [psutil]: https://github.com/giampaolo/psutil
 [scikit-image]: https://github.com/scikit-image/scikit-image
 [twisted-iocpsupport]: https://github.com/twisted/twisted-iocpsupport
+[cmake]: https://github.com/scikit-build/cmake-python-distributions
 [websockets]: https://github.com/aaugustin/websockets
 [pyzmq]: https://github.com/zeromq/pyzmq
 [aiortc]: https://github.com/aiortc/aiortc
@@ -215,8 +220,8 @@ Here are some repos that use cibuildwheel.
 [ruptures]: https://github.com/deepcharles/ruptures
 [aioquic]: https://github.com/aiortc/aioquic
 [pikepdf]: https://github.com/pikepdf/pikepdf
-[DeepForest]: https://github.com/LAMDA-NJU/Deep-Forest
 [google neuroglancer]: https://github.com/google/neuroglancer
+[DeepForest]: https://github.com/LAMDA-NJU/Deep-Forest
 [AutoPy]: https://github.com/autopilot-rs/autopy
 [Parselmouth]: https://github.com/YannickJadoul/Parselmouth
 [python-rapidjson]: https://github.com/python-rapidjson/python-rapidjson
@@ -228,31 +233,32 @@ Here are some repos that use cibuildwheel.
 [KDEpy]: https://github.com/tommyod/KDEpy
 [cyvcf2]: https://github.com/brentp/cyvcf2
 [pybind11 python_example]: https://github.com/pybind/python_example
-[sourmash]: https://github.com/dib-lab/sourmash
 [dd-trace-py]: https://github.com/DataDog/dd-trace-py
-[iminuit]: https://github.com/scikit-hep/iminuit
+[sourmash]: https://github.com/dib-lab/sourmash
 [time-machine]: https://github.com/adamchainz/time-machine
-[matrixprofile]: https://github.com/matrix-profile-foundation/matrixprofile
+[iminuit]: https://github.com/scikit-hep/iminuit
 [CTranslate2]: https://github.com/OpenNMT/CTranslate2
+[matrixprofile]: https://github.com/matrix-profile-foundation/matrixprofile
 [jq.py]: https://github.com/mwilliamson/jq.py
 [Tokenizer]: https://github.com/OpenNMT/Tokenizer
 [PyGLM]: https://github.com/Zuzu-Typ/PyGLM
 [bx-python]: https://github.com/bxlab/bx-python
-[boost-histogram]: https://github.com/scikit-hep/boost-histogram
 [iDynTree]: https://github.com/robotology/idyntree
-[TgCrypto]: https://github.com/pyrogram/tgcrypto
+[boost-histogram]: https://github.com/scikit-hep/boost-histogram
 [pybase64]: https://github.com/mayeut/pybase64
+[TgCrypto]: https://github.com/pyrogram/tgcrypto
 [etebase-py]: https://github.com/etesync/etebase-py
+[fathon]: https://github.com/stfbnc/fathon
 [pyjet]: https://github.com/scikit-hep/pyjet
 [numpythia]: https://github.com/scikit-hep/numpythia
-[fathon]: https://github.com/stfbnc/fathon
 [polaroid]: https://github.com/daggy1234/polaroid
+[ninja]: https://github.com/scikit-build/ninja-python-distributions
 [GSD]: https://github.com/glotzerlab/gsd
 [pybind11 scikit_build_example]: https://github.com/pybind/scikit_build_example
+[Imagecodecs (fork)]: https://github.com/czaki/imagecodecs_build
 [pyinstrument_cext]: https://github.com/joerick/pyinstrument_cext
 [xmlstarlet]: https://github.com/dimitern/xmlstarlet
 [CorrectionLib]: https://github.com/cms-nanoAOD/correctionlib
-[Imagecodecs (fork)]: https://github.com/czaki/imagecodecs_build
 [SiPM]: https://github.com/EdoPro98/SimSiPM

 [appveyor icon]: docs/data/readme_icons/appveyor.svg
@@ -265,64 +271,66 @@ Here are some repos that use cibuildwheel.
 [apple icon]: docs/data/readme_icons/apple.svg
 [linux icon]: docs/data/readme_icons/linux.svg

-<!-- scikit-learn: 45793, last pushed 0 days ago -->
-<!-- Matplotlib: 13636, last pushed 0 days ago -->
-<!-- MyPy: 10696, last pushed 0 days ago -->
-<!-- psutil: 7319, last pushed 4 days ago -->
-<!-- scikit-image: 4342, last pushed 0 days ago -->
-<!-- twisted-iocpsupport: 4266, last pushed 0 days ago -->
-<!-- websockets: 3349, last pushed 0 days ago -->
-<!-- pyzmq: 2792, last pushed 1 days ago -->
-<!-- aiortc: 2396, last pushed 32 days ago -->
-<!-- River: 1604, last pushed 0 days ago -->
-<!-- coverage.py: 1592, last pushed 6 days ago -->
-<!-- numexpr: 1586, last pushed 75 days ago -->
-<!-- h5py: 1517, last pushed 1 days ago -->
-<!-- Dependency Injector: 1318, last pushed 20 days ago -->
-<!-- PyAV: 1246, last pushed 2 days ago -->
-<!-- PyTables: 1023, last pushed 53 days ago -->
-<!-- ruptures: 704, last pushed 0 days ago -->
-<!-- aioquic: 644, last pushed 13 days ago -->
-<!-- pikepdf: 624, last pushed 9 days ago -->
-<!-- DeepForest: 591, last pushed 6 days ago -->
-<!-- google neuroglancer: 586, last pushed 3 days ago -->
-<!-- AutoPy: 533, last pushed 251 days ago -->
-<!-- Parselmouth: 511, last pushed 0 days ago -->
-<!-- python-rapidjson: 420, last pushed 156 days ago -->
-<!-- Rtree: 403, last pushed 59 days ago -->
-<!-- python-snappy: 398, last pushed 82 days ago -->
-<!-- markupsafe: 390, last pushed 0 days ago -->
-<!-- H3-py: 376, last pushed 0 days ago -->
-<!-- pybind11 cmake_example: 271, last pushed 6 days ago -->
-<!-- KDEpy: 264, last pushed 7 days ago -->
-<!-- cyvcf2: 260, last pushed 19 days ago -->
-<!-- pybind11 python_example: 250, last pushed 6 days ago -->
-<!-- sourmash: 241, last pushed 0 days ago -->
-<!-- dd-trace-py: 237, last pushed 0 days ago -->
+<!-- scikit-learn: 46576, last pushed 0 days ago -->
+<!-- Matplotlib: 13940, last pushed 0 days ago -->
+<!-- MyPy: 11060, last pushed 0 days ago -->
+<!-- psutil: 7508, last pushed 0 days ago -->
+<!-- scikit-image: 4433, last pushed 0 days ago -->
+<!-- twisted-iocpsupport: 4304, last pushed 1 days ago -->
+<!-- cmake: 4022, last pushed 0 days ago -->
+<!-- websockets: 3472, last pushed 0 days ago -->
+<!-- pyzmq: 2857, last pushed 0 days ago -->
+<!-- aiortc: 2485, last pushed 13 days ago -->
+<!-- River: 1773, last pushed 1 days ago -->
+<!-- coverage.py: 1658, last pushed 0 days ago -->
+<!-- numexpr: 1607, last pushed 17 days ago -->
+<!-- h5py: 1546, last pushed 2 days ago -->
+<!-- Dependency Injector: 1463, last pushed 0 days ago -->
+<!-- PyAV: 1297, last pushed 48 days ago -->
+<!-- PyTables: 1044, last pushed 5 days ago -->
+<!-- ruptures: 764, last pushed 2 days ago -->
+<!-- aioquic: 711, last pushed 0 days ago -->
+<!-- pikepdf: 695, last pushed 2 days ago -->
+<!-- google neuroglancer: 665, last pushed 0 days ago -->
+<!-- DeepForest: 634, last pushed 1 days ago -->
+<!-- AutoPy: 553, last pushed 37 days ago -->
+<!-- Parselmouth: 528, last pushed 31 days ago -->
+<!-- python-rapidjson: 424, last pushed 29 days ago -->
+<!-- Rtree: 414, last pushed 126 days ago -->
+<!-- python-snappy: 406, last pushed 3 days ago -->
+<!-- markupsafe: 406, last pushed 18 days ago -->
+<!-- H3-py: 402, last pushed 42 days ago -->
+<!-- pybind11 cmake_example: 290, last pushed 8 days ago -->
+<!-- KDEpy: 286, last pushed 51 days ago -->
+<!-- cyvcf2: 265, last pushed 4 days ago -->
+<!-- pybind11 python_example: 258, last pushed 6 days ago -->
+<!-- dd-trace-py: 256, last pushed 1 days ago -->
+<!-- sourmash: 253, last pushed 0 days ago -->
+<!-- time-machine: 186, last pushed 5 days ago -->
 <!-- iminuit: 181, last pushed 0 days ago -->
-<!-- time-machine: 160, last pushed 0 days ago -->
-<!-- matrixprofile: 158, last pushed 68 days ago -->
-<!-- CTranslate2: 157, last pushed 0 days ago -->
-<!-- jq.py: 152, last pushed 15 days ago -->
-<!-- Tokenizer: 140, last pushed 14 days ago -->
-<!-- PyGLM: 103, last pushed 7 days ago -->
-<!-- bx-python: 102, last pushed 47 days ago -->
-<!-- boost-histogram: 78, last pushed 0 days ago -->
-<!-- iDynTree: 75, last pushed 3 days ago -->
-<!-- TgCrypto: 64, last pushed 16 days ago -->
-<!-- pybase64: 62, last pushed 1 days ago -->
-<!-- etebase-py: 50, last pushed 134 days ago -->
-<!-- pyjet: 28, last pushed 6 days ago -->
-<!-- numpythia: 28, last pushed 15 days ago -->
-<!-- fathon: 25, last pushed 65 days ago -->
-<!-- polaroid: 16, last pushed 69 days ago -->
-<!-- GSD: 16, last pushed 1 days ago -->
-<!-- pybind11 scikit_build_example: 14, last pushed 6 days ago -->
-<!-- pyinstrument_cext: 10, last pushed 95 days ago -->
-<!-- xmlstarlet: 7, last pushed 29 days ago -->
-<!-- CorrectionLib: 5, last pushed 5 days ago -->
-<!-- Imagecodecs (fork): 3, last pushed 19 days ago -->
-<!-- SiPM: 2, last pushed 15 days ago -->
+<!-- CTranslate2: 177, last pushed 2 days ago -->
+<!-- matrixprofile: 174, last pushed 29 days ago -->
+<!-- jq.py: 164, last pushed 32 days ago -->
+<!-- Tokenizer: 150, last pushed 30 days ago -->
+<!-- PyGLM: 106, last pushed 4 days ago -->
+<!-- bx-python: 104, last pushed 16 days ago -->
+<!-- iDynTree: 84, last pushed 1 days ago -->
+<!-- boost-histogram: 83, last pushed 1 days ago -->
+<!-- pybase64: 70, last pushed 5 days ago -->
+<!-- TgCrypto: 68, last pushed 55 days ago -->
+<!-- etebase-py: 51, last pushed 201 days ago -->
+<!-- fathon: 32, last pushed 52 days ago -->
+<!-- pyjet: 29, last pushed 66 days ago -->
+<!-- numpythia: 29, last pushed 0 days ago -->
+<!-- polaroid: 19, last pushed 3 days ago -->
+<!-- ninja: 19, last pushed 0 days ago -->
+<!-- GSD: 16, last pushed 3 days ago -->
+<!-- pybind11 scikit_build_example: 15, last pushed 6 days ago -->
+<!-- Imagecodecs (fork): 13, last pushed 29 days ago -->
+<!-- pyinstrument_cext: 10, last pushed 9 days ago -->
+<!-- xmlstarlet: 7, last pushed 2 days ago -->
+<!-- CorrectionLib: 6, last pushed 8 days ago -->
+<!-- SiPM: 4, last pushed 15 days ago -->

 <!-- END bin/projects.py -->

@@ -346,6 +354,32 @@ Changelog

 <!--changelog-start-->

+### v2.0.1
+
+_25 July 2021_
+
+- 📚 Docs improvements (#767)
+- 🛠 Dependency updates, including delocate 0.9.0.
+
+### v2.0.0 🎉
+
+_16 July 2021_
+
+- 🌟 You can now configure cibuildwheel options inside your project's `pyproject.toml`! Environment variables still work of course. Check out the [documentation](https://cibuildwheel.readthedocs.io/en/stable/options/#setting-options) for more info.
+- 🌟 Added support for building wheels with [build](https://github.com/pypa/build), as well as pip. This feature is controlled with the [`CIBW_BUILD_FRONTEND`](https://cibuildwheel.readthedocs.io/en/stable/options/#build-frontend) option.
+- 🌟 Added the ability to test building wheels on CPython 3.10! Because CPython 3.10 is in beta, these wheels should not be distributed, because they might not be compatible with the final release, but it's available to build for testing purposes. Use the flag [`--prerelease-pythons` or `CIBW_PRERELEASE_PYTHONS`](https://cibuildwheel.readthedocs.io/en/stable/options/#prerelease-pythons) to test. (#675) This version of cibuildwheel includes CPython 3.10.0b4.
+- ⚠️ **Removed support for building Python 2.7 and Python 3.5 wheels**, for both CPython and PyPy. If you still need to build on these versions, please use the latest v1.x version. (#596)
+- ✨ Added the ability to build CPython 3.8 wheels for Apple Silicon. (#704)
+- 🛠 Update to the latest build dependencies, including Auditwheel 4. (#633)
+- 🛠 Use the unified pypa/manylinux images to build PyPy (#671)
+- 🐛 Numerous bug fixes & docs improvements
+
+### v1.12.0
+
+_22 June 2021_
+
+- ✨ Adds support building macOS universal2/arm64 wheels on Python 3.8.
+
 ### v1.11.1

 _28 May 2021_
@@ -17,12 +17,12 @@ runs:
  using: composite
  steps:

-    # This needs powershell-core because github.action path is a Windows-style
-    # path on Windows.  Powershell-core understands both types of paths.
+    # Redirecting stderr to stdout to fix interleaving issue in Actions.
    - run: >
        pipx run
-        --spec ${{ github.action_path }}
+        --spec '${{ github.action_path }}'
        cibuildwheel
        ${{ inputs.package-dir }}
        --output-dir ${{ inputs.output-dir }}
-      shell: pwsh
+        2>&1
+      shell: bash
@@ -15,7 +15,7 @@ init:
 - cmd: set PATH=C:\Python37;C:\Python37\Scripts;%PATH%
 - ps: |
      $BRANCH = if ($env:APPVEYOR_PULL_REQUEST_HEAD_REPO_BRANCH) { $env:APPVEYOR_PULL_REQUEST_HEAD_REPO_BRANCH } else { $env:APPVEYOR_REPO_BRANCH }
-      if (-not ($BRANCH -eq 'master' -or $BRANCH.ToLower().StartsWith('appveyor-'))) {
+      if (-not ($BRANCH -eq 'main' -or $BRANCH.ToLower().StartsWith('appveyor-'))) {
        $env:PYTEST_ADDOPTS='-k "unit_test or test_0_basic" --suppress-no-test-exit-code'
      }

@@ -27,7 +27,7 @@ test_script: python -u ./bin/run_tests.py

 branches:
  only:
-    - master
+    - main

 skip_commits:
  files:
@@ -40,7 +40,7 @@ def main():
    timestamp = time.strftime("%Y-%m-%dT%H-%M-%S", time.gmtime())
    branch_name = f"update-constraints-{timestamp}"

-    shell(f"git checkout -b {branch_name} origin/master", check=True)
+    shell(f"git checkout -b {branch_name} origin/main", check=True)

    try:
        shell("bin/update_dependencies.py", check=True)
@@ -63,7 +63,7 @@ def main():
                "pr",
                "create",
                "--repo=pypa/cibuildwheel",
-                "--base=master",
+                "--base=main",
                "--title=Update dependencies",
                f"--body='{body}'",
            ],
@@ -62,7 +62,7 @@ class Project:
                print(f"Broken: {self.stars_repo}")
                raise

-            self.num_stars = repo.stargazers_count
+            self.num_stars: int = repo.stargazers_count
            self.pushed_at = repo.pushed_at
            if not self.notes:
                notes = repo.description
@@ -1,142 +1,40 @@
 #!/usr/bin/env python3
-from __future__ import annotations
+# This file supports 3.6+

-import configparser
 import os
 import shutil
 import subprocess
 import sys
-from typing import NamedTuple
+from pathlib import Path

-import requests
+DIR = Path(__file__).parent.resolve()
+RESOURCES = DIR.parent / "cibuildwheel/resources"

-os.chdir(os.path.dirname(__file__))
-os.chdir("..")
+python_version = "".join(str(v) for v in sys.version_info[:2])
+
+env = os.environ.copy()

 # CUSTOM_COMPILE_COMMAND is a pip-compile option that tells users how to
 # regenerate the constraints files
-os.environ["CUSTOM_COMPILE_COMMAND"] = "bin/update_dependencies.py"
+env["CUSTOM_COMPILE_COMMAND"] = "bin/update_dependencies.py"

-PYTHON_VERSIONS = ["27", "35", "36", "37", "38", "39"]
+os.chdir(DIR.parent)

-if "--no-docker" in sys.argv:
-    for python_version in PYTHON_VERSIONS:
-        subprocess.run(
-            [
-                f"./env{python_version}/bin/pip-compile",
-                "--allow-unsafe",
-                "--upgrade",
-                "cibuildwheel/resources/constraints.in",
-                f"--output-file=cibuildwheel/resources/constraints-python{python_version}.txt",
-            ],
-            check=True,
-        )
-else:
-    # latest manylinux2010 image with cpython 2.7 support
-    image_runner = "quay.io/pypa/manylinux2010_x86_64:2021-02-06-3d322a5"
-    subprocess.run(["docker", "pull", image_runner], check=True)
-    for python_version in PYTHON_VERSIONS:
-        abi_flags = "" if int(python_version) >= 38 else "m"
-        python_path = f"/opt/python/cp{python_version}-cp{python_version}{abi_flags}/bin/"
-        command = (
-            f"{python_path}pip install pip-tools && "
-            f"{python_path}pip-compile --allow-unsafe --upgrade "
-            "cibuildwheel/resources/constraints.in "
-            f"--output-file cibuildwheel/resources/constraints-python{python_version}.txt"
-        )
-        subprocess.run(
-            [
-                "docker",
-                "run",
-                "--rm",
-                "--env=CUSTOM_COMPILE_COMMAND",
-                f"--volume={os.getcwd()}:/volume",
-                "--workdir=/volume",
-                image_runner,
-                "bash",
-                "-c",
-                command,
-            ],
-            check=True,
-        )
-
-# default constraints.txt
-shutil.copyfile(
-    f"cibuildwheel/resources/constraints-python{PYTHON_VERSIONS[-1]}.txt",
-    "cibuildwheel/resources/constraints.txt",
+subprocess.run(
+    [
+        "pip-compile",
+        "--allow-unsafe",
+        "--upgrade",
+        "cibuildwheel/resources/constraints.in",
+        f"--output-file=cibuildwheel/resources/constraints-python{python_version}.txt",
+    ],
+    check=True,
+    env=env,
 )

-
-class Image(NamedTuple):
-    manylinux_version: str
-    platform: str
-    image_name: str
-    tag: str | None
-
-
-images = [
-    Image("manylinux1", "x86_64", "quay.io/pypa/manylinux1_x86_64", None),
-    Image("manylinux1", "i686", "quay.io/pypa/manylinux1_i686", None),
-    # Images for manylinux2010 are pinned to the latest tag supporting cp27
-    Image("manylinux2010", "x86_64", "quay.io/pypa/manylinux2010_x86_64", "2021-02-06-3d322a5"),
-    Image("manylinux2010", "i686", "quay.io/pypa/manylinux2010_i686", "2021-02-06-3d322a5"),
-    Image("manylinux2010", "pypy_x86_64", "pypywheels/manylinux2010-pypy_x86_64", None),
-    # 2014 images
-    Image("manylinux2014", "x86_64", "quay.io/pypa/manylinux2014_x86_64", None),
-    Image("manylinux2014", "i686", "quay.io/pypa/manylinux2014_i686", None),
-    Image("manylinux2014", "aarch64", "quay.io/pypa/manylinux2014_aarch64", None),
-    Image("manylinux2014", "ppc64le", "quay.io/pypa/manylinux2014_ppc64le", None),
-    Image("manylinux2014", "s390x", "quay.io/pypa/manylinux2014_s390x", None),
-    # 2_24 images
-    Image("manylinux_2_24", "x86_64", "quay.io/pypa/manylinux_2_24_x86_64", None),
-    Image("manylinux_2_24", "i686", "quay.io/pypa/manylinux_2_24_i686", None),
-    Image("manylinux_2_24", "aarch64", "quay.io/pypa/manylinux_2_24_aarch64", None),
-    Image("manylinux_2_24", "ppc64le", "quay.io/pypa/manylinux_2_24_ppc64le", None),
-    Image("manylinux_2_24", "s390x", "quay.io/pypa/manylinux_2_24_s390x", None),
-]
-
-config = configparser.ConfigParser()
-
-for image in images:
-    # get the tag name whose digest matches 'latest'
-    if image.tag is not None:
-        # image has been pinned, do not update
-        tag_name = image.tag
-    elif image.image_name.startswith("quay.io/"):
-        _, _, repository_name = image.image_name.partition("/")
-        response = requests.get(
-            f"https://quay.io/api/v1/repository/{repository_name}?includeTags=true"
-        )
-        response.raise_for_status()
-        repo_info = response.json()
-        tags_dict = repo_info["tags"]
-
-        latest_tag = tags_dict.pop("latest")
-        # find the tag whose manifest matches 'latest'
-        tag_name = next(
-            name
-            for (name, info) in tags_dict.items()
-            if info["manifest_digest"] == latest_tag["manifest_digest"]
-        )
-    else:
-        response = requests.get(f"https://hub.docker.com/v2/repositories/{image.image_name}/tags")
-        response.raise_for_status()
-        tags = response.json()["results"]
-
-        latest_tag = next(tag for tag in tags if tag["name"] == "latest")
-        # i don't know what it would mean to have multiple images per tag
-        assert len(latest_tag["images"]) == 1
-        digest = latest_tag["images"][0]["digest"]
-
-        pinned_tag = next(
-            tag for tag in tags if tag != latest_tag and tag["images"][0]["digest"] == digest
-        )
-        tag_name = pinned_tag["name"]
-
-    if not config.has_section(image.platform):
-        config[image.platform] = {}
-
-    config[image.platform][image.manylinux_version] = f"{image.image_name}:{tag_name}"
-
-with open("cibuildwheel/resources/pinned_docker_images.cfg", "w") as f:
-    config.write(f)
+# default constraints.txt
+if python_version == "39":
+    shutil.copyfile(
+        RESOURCES / f"constraints-python{python_version}.txt",
+        RESOURCES / "constraints.txt",
+    )
@@ -0,0 +1,93 @@
+#!/usr/bin/env python3
+from __future__ import annotations
+
+import configparser
+from pathlib import Path
+from typing import NamedTuple
+
+import requests
+
+DIR = Path(__file__).parent.resolve()
+RESOURCES = DIR.parent / "cibuildwheel/resources"
+
+
+class Image(NamedTuple):
+    manylinux_version: str
+    platform: str
+    image_name: str
+    tag: str | None  # Set this to pin the image
+
+
+images = [
+    Image("manylinux1", "x86_64", "quay.io/pypa/manylinux1_x86_64", None),
+    Image("manylinux1", "i686", "quay.io/pypa/manylinux1_i686", None),
+    # 2010 images
+    Image("manylinux2010", "x86_64", "quay.io/pypa/manylinux2010_x86_64", None),
+    Image("manylinux2010", "i686", "quay.io/pypa/manylinux2010_i686", None),
+    Image("manylinux2010", "pypy_x86_64", "quay.io/pypa/manylinux2010_x86_64", None),
+    Image("manylinux2010", "pypy_i686", "quay.io/pypa/manylinux2010_i686", None),
+    # 2014 images
+    Image("manylinux2014", "x86_64", "quay.io/pypa/manylinux2014_x86_64", None),
+    Image("manylinux2014", "i686", "quay.io/pypa/manylinux2014_i686", None),
+    Image("manylinux2014", "aarch64", "quay.io/pypa/manylinux2014_aarch64", None),
+    Image("manylinux2014", "ppc64le", "quay.io/pypa/manylinux2014_ppc64le", None),
+    Image("manylinux2014", "s390x", "quay.io/pypa/manylinux2014_s390x", None),
+    Image("manylinux2014", "pypy_x86_64", "quay.io/pypa/manylinux2014_x86_64", None),
+    Image("manylinux2014", "pypy_i686", "quay.io/pypa/manylinux2014_i686", None),
+    Image("manylinux2014", "pypy_aarch64", "quay.io/pypa/manylinux2014_aarch64", None),
+    # 2_24 images
+    Image("manylinux_2_24", "x86_64", "quay.io/pypa/manylinux_2_24_x86_64", None),
+    Image("manylinux_2_24", "i686", "quay.io/pypa/manylinux_2_24_i686", None),
+    Image("manylinux_2_24", "aarch64", "quay.io/pypa/manylinux_2_24_aarch64", None),
+    Image("manylinux_2_24", "ppc64le", "quay.io/pypa/manylinux_2_24_ppc64le", None),
+    Image("manylinux_2_24", "s390x", "quay.io/pypa/manylinux_2_24_s390x", None),
+    Image("manylinux_2_24", "pypy_x86_64", "quay.io/pypa/manylinux_2_24_x86_64", None),
+    Image("manylinux_2_24", "pypy_i686", "quay.io/pypa/manylinux_2_24_i686", None),
+    Image("manylinux_2_24", "pypy_aarch64", "quay.io/pypa/manylinux_2_24_aarch64", None),
+]
+
+config = configparser.ConfigParser()
+
+for image in images:
+    # get the tag name whose digest matches 'latest'
+    if image.tag is not None:
+        # image has been pinned, do not update
+        tag_name = image.tag
+    elif image.image_name.startswith("quay.io/"):
+        _, _, repository_name = image.image_name.partition("/")
+        response = requests.get(
+            f"https://quay.io/api/v1/repository/{repository_name}?includeTags=true"
+        )
+        response.raise_for_status()
+        repo_info = response.json()
+        tags_dict = repo_info["tags"]
+
+        latest_tag = tags_dict.pop("latest")
+        # find the tag whose manifest matches 'latest'
+        tag_name = next(
+            name
+            for (name, info) in tags_dict.items()
+            if info["manifest_digest"] == latest_tag["manifest_digest"]
+        )
+    else:
+        response = requests.get(f"https://hub.docker.com/v2/repositories/{image.image_name}/tags")
+        response.raise_for_status()
+        tags = response.json()["results"]
+
+        latest_tag = next(tag for tag in tags if tag["name"] == "latest")
+        # i don't know what it would mean to have multiple images per tag
+        assert len(latest_tag["images"]) == 1
+        digest = latest_tag["images"][0]["digest"]
+
+        pinned_tag = next(
+            tag for tag in tags if tag != latest_tag and tag["images"][0]["digest"] == digest
+        )
+        tag_name = pinned_tag["name"]
+
+    if not config.has_section(image.platform):
+        config[image.platform] = {}
+
+    config[image.platform][image.manylinux_version] = f"{image.image_name}:{tag_name}"
+
+with open(RESOURCES / "pinned_docker_images.cfg", "w") as f:
+    config.write(f)
@@ -6,7 +6,7 @@ import copy
 import difflib
 import logging
 from pathlib import Path
-from typing import Union
+from typing import Any, Union

 import click
 import requests
@@ -79,23 +79,26 @@ class WindowsVersions:
        response.raise_for_status()
        cp_info = response.json()

-        versions = (Version(v) for v in cp_info["versions"])
-        self.versions = sorted(v for v in versions if not v.is_devrelease)
+        self.version_dict = {Version(v): v for v in cp_info["versions"]}

    def update_version_windows(self, spec: Specifier) -> ConfigWinCP | None:
-        versions = sorted(v for v in self.versions if spec.contains(v))
-        if not all(v.is_prerelease for v in versions):
-            versions = [v for v in versions if not v.is_prerelease]
+
+        # Specifier.filter selects all non pre-releases that match the spec,
+        # unless there are only pre-releases, then it selects pre-releases
+        # instead (like pip)
+        unsorted_versions = spec.filter(self.version_dict)
+        versions = sorted(unsorted_versions, reverse=True)
+
        log.debug(f"Windows {self.arch} {spec} has {', '.join(str(v) for v in versions)}")

        if not versions:
            return None

-        version = versions[-1]
+        version = versions[0]
        identifier = f"cp{version.major}{version.minor}-{self.arch}"
        return ConfigWinCP(
            identifier=identifier,
-            version=str(version),
+            version=self.version_dict[version],
            arch=self.arch_str,
        )

@@ -118,26 +121,33 @@ class PyPyVersions:
        ]
        self.arch = arch_str

-    def update_version_windows(self, spec: Specifier) -> ConfigWinCP:
-        if self.arch != "32":
-            raise RuntimeError("64 bit releases not supported yet on Windows")
+    def get_arch_file(self, release: dict[str, Any]) -> str:
+        urls: list[str] = [
+            rf["download_url"]
+            for rf in release["files"]
+            if "" in rf["platform"] == f"win{self.arch}"
+        ]
+        return urls[0] if urls else ""

+    def update_version_windows(self, spec: Specifier) -> ConfigWinCP:
        releases = [r for r in self.releases if spec.contains(r["python_version"])]
-        releases = sorted(releases, key=lambda r: r["pypy_version"])
+        releases = sorted(releases, key=lambda r: r["pypy_version"])  # type: ignore
+        releases = [r for r in releases if self.get_arch_file(r)]

        if not releases:
            raise RuntimeError(f"PyPy Win {self.arch} not found for {spec}! {self.releases}")

+        version_arch = "win32" if self.arch == "32" else "win_amd64"
+
        release = releases[-1]
        version = release["python_version"]
-        identifier = f"pp{version.major}{version.minor}-win32"
-
-        (url,) = [rf["download_url"] for rf in release["files"] if "" in rf["platform"] == "win32"]
+        identifier = f"pp{version.major}{version.minor}-{version_arch}"
+        url = self.get_arch_file(release)

        return ConfigWinPP(
            identifier=identifier,
            version=f"{version.major}.{version.minor}",
-            arch="32",
+            arch=self.arch,
            url=url,
        )

@@ -146,7 +156,7 @@ class PyPyVersions:
            raise RuntimeError("Other archs not supported yet on macOS")

        releases = [r for r in self.releases if spec.contains(r["python_version"])]
-        releases = sorted(releases, key=lambda r: r["pypy_version"])
+        releases = sorted(releases, key=lambda r: r["pypy_version"])  # type: ignore

        if not releases:
            raise RuntimeError(f"PyPy macOS {self.arch} not found for {spec}!")
@@ -155,11 +165,11 @@ class PyPyVersions:
        version = release["python_version"]
        identifier = f"pp{version.major}{version.minor}-macosx_x86_64"

-        (url,) = [
+        (url,) = (
            rf["download_url"]
            for rf in release["files"]
            if "" in rf["platform"] == "darwin" and rf["arch"] == "x64"
-        ]
+        )

        return ConfigMacOS(
            identifier=identifier,
@@ -183,31 +193,38 @@ class CPythonVersions:
            # Removing the prefix, Python 3.9 would use: release["name"].removeprefix("Python ")
            version = Version(release["name"][7:])

-            if not version.is_prerelease and not version.is_devrelease:
-                uri = int(release["resource_uri"].rstrip("/").split("/")[-1])
-                self.versions_dict[version] = uri
+            uri = int(release["resource_uri"].rstrip("/").split("/")[-1])
+            self.versions_dict[version] = uri

-    def update_version_macos(self, identifier: str, spec: Specifier) -> ConfigMacOS | None:
-        file_idents = ("macos11.pkg", "macosx10.9.pkg", "macosx10.6.pkg")
-        sorted_versions = sorted(v for v in self.versions_dict if spec.contains(v))
+    def update_version_macos(
+        self, identifier: str, version: Version, spec: Specifier
+    ) -> ConfigMacOS | None:

-        for version in reversed(sorted_versions):
+        # see note above on Specifier.filter
+        unsorted_versions = spec.filter(self.versions_dict)
+        sorted_versions = sorted(unsorted_versions, reverse=True)
+
+        if version <= Version("3.8.9999"):
+            file_ident = "macosx10.9.pkg"
+        else:
+            file_ident = "macos11.pkg"
+
+        for new_version in sorted_versions:
            # Find the first patch version that contains the requested file
-            uri = self.versions_dict[version]
+            uri = self.versions_dict[new_version]
            response = requests.get(
                f"https://www.python.org/api/v2/downloads/release_file/?release={uri}"
            )
            response.raise_for_status()
            file_info = response.json()

-            for file_ident in file_idents:
-                urls = [rf["url"] for rf in file_info if file_ident in rf["url"]]
-                if urls:
-                    return ConfigMacOS(
-                        identifier=identifier,
-                        version=f"{version.major}.{version.minor}",
-                        url=urls[0],
-                    )
+            urls = [rf["url"] for rf in file_info if file_ident in rf["url"]]
+            if urls:
+                return ConfigMacOS(
+                    identifier=identifier,
+                    version=f"{new_version.major}.{new_version.minor}",
+                    url=urls[0],
+                )

        return None

@@ -220,7 +237,7 @@ class AllVersions:
    def __init__(self) -> None:
        self.windows_32 = WindowsVersions("32")
        self.windows_64 = WindowsVersions("64")
-        self.windows_pypy = PyPyVersions("32")
+        self.windows_pypy_64 = PyPyVersions("64")

        self.macos_cpython = CPythonVersions()
        self.macos_pypy = PyPyVersions("64")
@@ -231,28 +248,25 @@ class AllVersions:
        spec = Specifier(f"=={version.major}.{version.minor}.*")
        log.info(f"Reading in '{identifier}' -> {spec} @ {version}")
        orig_config = copy.copy(config)
-        config_update: AnyConfig | None
+        config_update: AnyConfig | None = None

        # We need to use ** in update due to MyPy (probably a bug)
        if "macos" in identifier:
-            if identifier.startswith("pp"):
+            if identifier.startswith("cp"):
+                config_update = self.macos_cpython.update_version_macos(identifier, version, spec)
+            elif identifier.startswith("pp"):
                config_update = self.macos_pypy.update_version_macos(spec)
-            else:
-                config_update = self.macos_cpython.update_version_macos(identifier, spec)
-
-            assert config_update is not None, f"MacOS {spec} not found!"
-            config.update(**config_update)
        elif "win32" in identifier:
-            if identifier.startswith("pp"):
-                config.update(**self.windows_pypy.update_version_windows(spec))
-            else:
+            if identifier.startswith("cp"):
                config_update = self.windows_32.update_version_windows(spec)
-                if config_update:
-                    config.update(**config_update)
        elif "win_amd64" in identifier:
-            config_update = self.windows_64.update_version_windows(spec)
-            if config_update:
-                config.update(**config_update)
+            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)
+
+        assert config_update is not None, f"{identifier} not found!"
+        config.update(**config_update)

        if config != orig_config:
            log.info(f"  Updated {orig_config} to {config}")
@@ -261,7 +275,7 @@ class AllVersions:
@click.command()
@click.option("--force", is_flag=True)
@click.option(
-    "--level", default="INFO", type=click.Choice(["INFO", "DEBUG", "TRACE"], case_sensitive=False)
+    "--level", default="INFO", type=click.Choice(["WARNING", "INFO", "DEBUG"], case_sensitive=False)
 )
 def update_pythons(force: bool, level: str) -> None:

@@ -1 +1 @@
-__version__ = "1.11.1.post1"
+__version__ = "2.0.1"
@@ -5,7 +5,7 @@ import textwrap
 import traceback
 from configparser import ConfigParser
 from pathlib import Path
-from typing import Dict, List, Optional, Set, Union, overload
+from typing import Dict, List, Optional, Set, Union

 from packaging.specifiers import SpecifierSet

@@ -16,9 +16,11 @@ import cibuildwheel.util
 import cibuildwheel.windows
 from cibuildwheel.architecture import Architecture, allowed_architectures_check
 from cibuildwheel.environment import EnvironmentParseError, parse_environment
+from cibuildwheel.options import ConfigOptions
 from cibuildwheel.projectfiles import get_requires_python_str
 from cibuildwheel.typing import PLATFORMS, PlatformName, assert_never
 from cibuildwheel.util import (
+    BuildFrontend,
    BuildOptions,
    BuildSelector,
    DependencyConstraints,
@@ -28,39 +30,16 @@ from cibuildwheel.util import (
    resources_dir,
 )

-
-@overload
-def get_option_from_environment(
-    option_name: str, *, platform: Optional[str] = None, default: str
-) -> str:
-    ...  # noqa: E704
-
-
-@overload
-def get_option_from_environment(
-    option_name: str, *, platform: Optional[str] = None, default: None = None
-) -> Optional[str]:
-    ...  # noqa: E704 E302
-
-
-def get_option_from_environment(
-    option_name: str, *, platform: Optional[str] = None, default: Optional[str] = None
-) -> Optional[str]:  # noqa: E302
-    """
-    Returns an option from the environment, optionally scoped by the platform.
-
-    Example:
-      get_option_from_environment('CIBW_COLOR', platform='macos')
-
-      This will return the value of CIBW_COLOR_MACOS if it exists, otherwise the value of
-      CIBW_COLOR.
-    """
-    if platform:
-        option = os.environ.get(f"{option_name}_{platform.upper()}")
-        if option is not None:
-            return option
-
-    return os.environ.get(option_name, default)
+MANYLINUX_ARCHS = (
+    "x86_64",
+    "i686",
+    "pypy_x86_64",
+    "aarch64",
+    "ppc64le",
+    "s390x",
+    "pypy_aarch64",
+    "pypy_i686",
+)


 def main() -> None:
@@ -69,8 +48,9 @@ def main() -> None:
    parser = argparse.ArgumentParser(
        description="Build wheels for all the platforms.",
        epilog="""
-            Most options are supplied via environment variables.
-            See https://github.com/pypa/cibuildwheel#options for info.
+            Most options are supplied via environment variables or in
+            --config-file (pyproject.toml usually). See
+            https://github.com/pypa/cibuildwheel#options for info.
        """,
    )

@@ -104,10 +84,17 @@ def main() -> None:

    parser.add_argument(
        "--output-dir",
-        default=os.environ.get("CIBW_OUTPUT_DIR", "wheelhouse"),
        help="Destination folder for the wheels.",
    )

+    parser.add_argument(
+        "--config-file",
+        help="""
+            TOML config file for cibuildwheel. Defaults to pyproject.toml, but
+            can be overridden with this option.
+        """,
+    )
+
    parser.add_argument(
        "package_dir",
        default=".",
@@ -132,9 +119,13 @@ def main() -> None:
        help="Do not report an error code if the build does not match any wheels.",
    )

-    args = parser.parse_args()
+    parser.add_argument(
+        "--prerelease-pythons",
+        action="store_true",
+        help="Enable pre-release Python versions if available.",
+    )

-    detect_obsolete_options()
+    args = parser.parse_args()

    if args.platform != "auto":
        platform = args.platform
@@ -172,58 +163,79 @@ def main() -> None:
        sys.exit(2)

    package_dir = Path(args.package_dir)
-    output_dir = Path(args.output_dir)

-    if platform == "linux":
-        repair_command_default = "auditwheel repair -w {dest_dir} {wheel}"
-    elif platform == "macos":
-        repair_command_default = "delocate-listdeps {wheel} && delocate-wheel --require-archs {delocate_archs} -w {dest_dir} {wheel}"
-    elif platform == "windows":
-        repair_command_default = ""
+    manylinux_identifiers = {
+        f"manylinux-{build_platform}-image" for build_platform in MANYLINUX_ARCHS
+    }
+    disallow = {
+        "linux": {"dependency-versions"},
+        "macos": manylinux_identifiers,
+        "windows": manylinux_identifiers,
+    }
+    options = ConfigOptions(package_dir, args.config_file, platform=platform, disallow=disallow)
+    output_dir = Path(
+        args.output_dir
+        if args.output_dir is not None
+        else os.environ.get("CIBW_OUTPUT_DIR", "wheelhouse")
+    )
+
+    build_config = options("build", env_plat=False, sep=" ") or "*"
+    skip_config = options("skip", env_plat=False, sep=" ")
+    test_skip = options("test-skip", env_plat=False, sep=" ")
+
+    archs_config_str = args.archs or options("archs", sep=" ")
+
+    build_frontend_str = options("build-frontend", env_plat=False)
+    environment_config = options("environment", table={"item": '{k}="{v}"', "sep": " "})
+    before_all = options("before-all", sep=" && ")
+    before_build = options("before-build", sep=" && ")
+    repair_command = options("repair-wheel-command", sep=" && ")
+
+    dependency_versions = options("dependency-versions")
+    test_command = options("test-command", sep=" && ")
+    before_test = options("before-test", sep=" && ")
+    test_requires = options("test-requires", sep=" ").split()
+    test_extras = options("test-extras", sep=",")
+    build_verbosity_str = options("build-verbosity")
+
+    prerelease_pythons = args.prerelease_pythons or cibuildwheel.util.strtobool(
+        os.environ.get("CIBW_PRERELEASE_PYTHONS", "0")
+    )
+
+    build_frontend: BuildFrontend
+    if build_frontend_str == "build":
+        build_frontend = "build"
+    elif build_frontend_str == "pip":
+        build_frontend = "pip"
    else:
-        assert_never(platform)
-
-    build_config = os.environ.get("CIBW_BUILD") or "*"
-    skip_config = os.environ.get("CIBW_SKIP", "")
-    test_skip = os.environ.get("CIBW_TEST_SKIP", "")
-    environment_config = get_option_from_environment(
-        "CIBW_ENVIRONMENT", platform=platform, default=""
-    )
-    before_all = get_option_from_environment("CIBW_BEFORE_ALL", platform=platform, default="")
-    before_build = get_option_from_environment("CIBW_BEFORE_BUILD", platform=platform)
-    repair_command = get_option_from_environment(
-        "CIBW_REPAIR_WHEEL_COMMAND", platform=platform, default=repair_command_default
-    )
-    dependency_versions = get_option_from_environment(
-        "CIBW_DEPENDENCY_VERSIONS", platform=platform, default="pinned"
-    )
-    test_command = get_option_from_environment("CIBW_TEST_COMMAND", platform=platform)
-    before_test = get_option_from_environment("CIBW_BEFORE_TEST", platform=platform)
-    test_requires = get_option_from_environment(
-        "CIBW_TEST_REQUIRES", platform=platform, default=""
-    ).split()
-    test_extras = get_option_from_environment("CIBW_TEST_EXTRAS", platform=platform, default="")
-    build_verbosity_str = get_option_from_environment(
-        "CIBW_BUILD_VERBOSITY", platform=platform, default=""
-    )
+        msg = f"cibuildwheel: Unrecognised build frontend '{build_frontend}', only 'pip' and 'build' are supported"
+        print(msg, file=sys.stderr)
+        sys.exit(2)

    package_files = {"setup.py", "setup.cfg", "pyproject.toml"}

    if not any(package_dir.joinpath(name).exists() for name in package_files):
        names = ", ".join(sorted(package_files, reverse=True))
-        print(
-            f"cibuildwheel: Could not find any of {{{names}}} at root of package", file=sys.stderr
-        )
+        msg = f"cibuildwheel: Could not find any of {{{names}}} at root of package"
+        print(msg, file=sys.stderr)
        sys.exit(2)

+    # This is not supported in tool.cibuildwheel, as it comes from a standard location.
    # Passing this in as an environment variable will override pyproject.toml, setup.cfg, or setup.py
    requires_python_str: Optional[str] = os.environ.get(
        "CIBW_PROJECT_REQUIRES_PYTHON"
    ) or get_requires_python_str(package_dir)
    requires_python = None if requires_python_str is None else SpecifierSet(requires_python_str)

+    deprecated_selectors("CIBW_BUILD", build_config, error=True)
+    deprecated_selectors("CIBW_SKIP", skip_config)
+    deprecated_selectors("CIBW_TEST_SKIP", test_skip)
+
    build_selector = BuildSelector(
-        build_config=build_config, skip_config=skip_config, requires_python=requires_python
+        build_config=build_config,
+        skip_config=skip_config,
+        requires_python=requires_python,
+        prerelease_pythons=prerelease_pythons,
    )
    test_selector = TestSelector(skip_config=test_skip)

@@ -256,13 +268,6 @@ def main() -> None:
    # This needs to be passed on to the docker container in linux.py
    os.environ["CIBUILDWHEEL"] = "1"

-    if args.archs is not None:
-        archs_config_str = args.archs
-    else:
-        archs_config_str = get_option_from_environment(
-            "CIBW_ARCHS", platform=platform, default="auto"
-        )
-
    archs = Architecture.parse_config(archs_config_str, platform=platform)

    identifiers = get_build_identifiers(platform, build_selector, archs)
@@ -272,7 +277,7 @@ def main() -> None:
            print(identifier)
        sys.exit(0)

-    manylinux_images: Optional[Dict[str, str]] = None
+    manylinux_images: Dict[str, str] = {}
    if platform == "linux":
        pinned_docker_images_file = resources_dir / "pinned_docker_images.cfg"
        all_pinned_docker_images = ConfigParser()
@@ -283,13 +288,10 @@ def main() -> None:
        #   'pypy_x86_64': {'manylinux2010': '...' }
        #   ... }

-        manylinux_images = {}
-
-        for build_platform in ["x86_64", "i686", "pypy_x86_64", "aarch64", "ppc64le", "s390x"]:
+        for build_platform in MANYLINUX_ARCHS:
            pinned_images = all_pinned_docker_images[build_platform]

-            config_name = f"CIBW_MANYLINUX_{build_platform.upper()}_IMAGE"
-            config_value = os.environ.get(config_name)
+            config_value = options(f"manylinux-{build_platform}-image")

            if config_value is None:
                # default to manylinux2010 if it's available, otherwise manylinux2014
@@ -317,7 +319,8 @@ def main() -> None:
        repair_command=repair_command,
        environment=environment,
        dependency_constraints=dependency_constraints,
-        manylinux_images=manylinux_images,
+        manylinux_images=manylinux_images or None,
+        build_frontend=build_frontend,
    )

    # Python is buffering by default when running on the CI platforms, giving problems interleaving subprocess call output with unflushed calls to 'print'
@@ -352,35 +355,12 @@ def main() -> None:
            assert_never(platform)


-def detect_obsolete_options() -> None:
-    # Check the old 'MANYLINUX1_*_IMAGE' options
-    for (deprecated, alternative) in [
-        ("CIBW_MANYLINUX1_X86_64_IMAGE", "CIBW_MANYLINUX_X86_64_IMAGE"),
-        ("CIBW_MANYLINUX1_I686_IMAGE", "CIBW_MANYLINUX_I686_IMAGE"),
-    ]:
-        if deprecated in os.environ:
-            print(
-                f"'{deprecated}' has been deprecated, and will be removed in a future release. Use the option '{alternative}' instead."
-            )
-            if alternative not in os.environ:
-                print(f"Using value of option '{deprecated}' as replacement for '{alternative}'")
-                os.environ[alternative] = os.environ[deprecated]
-            else:
-                print(f"Option '{alternative}' is not empty. Please unset '{deprecated}'")
-                sys.exit(2)
-
-    # Check for deprecated identifiers in 'CIBW_BUILD' and 'CIBW_SKIP' options
-    for option in ["CIBW_BUILD", "CIBW_SKIP"]:
-        for deprecated, alternative in [
-            ("manylinux1", "manylinux"),
-            ("macosx_10_6_intel", "macosx_x86_64"),
-            ("macosx_10_9_x86_64", "macosx_x86_64"),
-        ]:
-            if option in os.environ and deprecated in os.environ[option]:
-                print(
-                    f"Build identifiers with '{deprecated}' have been deprecated. Replacing all occurences of '{deprecated}' with '{alternative}' in the option '{option}'"
-                )
-                os.environ[option] = os.environ[option].replace(deprecated, alternative)
+def deprecated_selectors(name: str, selector: str, *, error: bool = False) -> None:
+    if "p2" in selector or "p35" in selector:
+        msg = f"cibuildwheel 2.x no longer supports Python < 3.6. Please use the 1.x series or update {name}"
+        print(msg, file=sys.stderr)
+        if error:
+            sys.exit(4)


 def print_preamble(platform: str, build_options: BuildOptions) -> None:
@@ -7,7 +7,7 @@ from typing import List, NamedTuple, Set
 from .architecture import Architecture
 from .docker_container import DockerContainer
 from .logger import log
-from .typing import PathOrStr
+from .typing import PathOrStr, assert_never
 from .util import (
    BuildOptions,
    BuildSelector,
@@ -15,7 +15,6 @@ from .util import (
    get_build_verbosity_extra_flags,
    prepare_command,
    read_python_configs,
-    resources_dir,
 )


@@ -70,6 +69,8 @@ def build(options: BuildOptions) -> None:
        ("cp", "manylinux_ppc64le", options.manylinux_images["ppc64le"]),
        ("cp", "manylinux_s390x", options.manylinux_images["s390x"]),
        ("pp", "manylinux_x86_64", options.manylinux_images["pypy_x86_64"]),
+        ("pp", "manylinux_aarch64", options.manylinux_images["pypy_aarch64"]),
+        ("pp", "manylinux_i686", options.manylinux_images["pypy_i686"]),
    ]

    cwd = Path.cwd()
@@ -122,26 +123,6 @@ def build(options: BuildOptions) -> None:
                    log.build_start(config.identifier)

                    dependency_constraint_flags: List[PathOrStr] = []
-                    if config.identifier.startswith("pp"):
-                        # Patch PyPy to make sure headers get installed into a venv
-                        patch_version = "_27" if config.version == "2.7" else ""
-                        patch_path = resources_dir / f"pypy_venv{patch_version}.patch"
-                        patch_docker_path = PurePath("/pypy_venv.patch")
-                        docker.copy_into(patch_path, patch_docker_path)
-                        try:
-                            docker.call(
-                                [
-                                    "patch",
-                                    "--force",
-                                    "-p1",
-                                    "-d",
-                                    config.path,
-                                    "-i",
-                                    patch_docker_path,
-                                ]
-                            )
-                        except subprocess.CalledProcessError:
-                            print("PyPy patch not applied", file=sys.stderr)

                    if options.dependency_constraints:
                        constraints_file = options.dependency_constraints.get_for_python_version(
@@ -164,7 +145,7 @@ def build(options: BuildOptions) -> None:
                        env, executor=docker.environment_executor
                    )

-                    # check config python and pip are still on PATH
+                    # check config python is still on PATH
                    which_python = docker.call(
                        ["which", "python"], env=env, capture_output=True
                    ).strip()
@@ -199,18 +180,38 @@ def build(options: BuildOptions) -> None:
                    docker.call(["rm", "-rf", built_wheel_dir])
                    docker.call(["mkdir", "-p", built_wheel_dir])

-                    docker.call(
-                        [
-                            "pip",
-                            "wheel",
-                            container_package_dir,
-                            "--wheel-dir",
-                            built_wheel_dir,
-                            "--no-deps",
-                            *get_build_verbosity_extra_flags(options.build_verbosity),
-                        ],
-                        env=env,
-                    )
+                    verbosity_flags = get_build_verbosity_extra_flags(options.build_verbosity)
+
+                    if options.build_frontend == "pip":
+                        docker.call(
+                            [
+                                "python",
+                                "-m",
+                                "pip",
+                                "wheel",
+                                container_package_dir,
+                                f"--wheel-dir={built_wheel_dir}",
+                                "--no-deps",
+                                *verbosity_flags,
+                            ],
+                            env=env,
+                        )
+                    elif options.build_frontend == "build":
+                        config_setting = " ".join(verbosity_flags)
+                        docker.call(
+                            [
+                                "python",
+                                "-m",
+                                "build",
+                                container_package_dir,
+                                "--wheel",
+                                f"--outdir={built_wheel_dir}",
+                                f"--config-setting={config_setting}",
+                            ],
+                            env=env,
+                        )
+                    else:
+                        assert_never(options.build_frontend)

                    built_wheel = docker.glob(built_wheel_dir, "*.whl")[0]

@@ -310,8 +311,11 @@ def build(options: BuildOptions) -> None:


 def troubleshoot(package_dir: Path, error: Exception) -> None:
-    if isinstance(error, subprocess.CalledProcessError) and error.cmd[0:2] == ["pip", "wheel"]:
-        # the 'pip wheel' step failed.
+    if isinstance(error, subprocess.CalledProcessError) and (
+        error.cmd[0:4] == ["python", "-m", "pip", "wheel"]
+        or error.cmd[0:3] == ["python", "-m", "build"]
+    ):
+        # the wheel build step failed
        print("Checking for common errors...")
        so_files = list(package_dir.glob("**/*.so"))

@@ -186,7 +186,7 @@ def build_description_from_identifier(identifier: str) -> str:
    build_description = ""

    python_interpreter = python_identifier[0:2]
-    python_version = python_identifier[2:4]
+    python_version = python_identifier[2:]

    if python_interpreter == "cp":
        build_description += "CPython"
@@ -195,7 +195,7 @@ def build_description_from_identifier(identifier: str) -> str:
    else:
        raise Exception("unknown python")

-    build_description += f" {python_version[0]}.{python_version[1]} "
+    build_description += f" {python_version[0]}.{python_version[1:]} "

    try:
        build_description += PLATFORM_IDENTIFIER_DESCIPTIONS[platform_identifier]
@@ -12,18 +12,18 @@ from typing import Any, Dict, List, NamedTuple, Optional, Sequence, Set, Tuple,
 from .architecture import Architecture
 from .environment import ParsedEnvironment
 from .logger import log
-from .typing import Literal, PathOrStr
+from .typing import Literal, PathOrStr, assert_never
 from .util import (
+    BuildFrontend,
    BuildOptions,
    BuildSelector,
    NonPlatformWheelError,
    download,
    get_build_verbosity_extra_flags,
-    get_pip_script,
+    get_pip_version,
    install_certifi_script,
    prepare_command,
    read_python_configs,
-    resources_dir,
    unwrap,
 )

@@ -111,21 +111,6 @@ def get_python_configurations(
                c for c in python_configurations if not c.identifier.startswith("pp")
            ]

-        if any(c.identifier.startswith("cp35") for c in python_configurations):
-            # CPython 3.5 doesn't work on macOS 11
-            log.warning(
-                unwrap(
-                    """
-                    CPython 3.5 is unsupported when building on macOS 11. To build CPython 3.5
-                    wheels, build on an older OS, such as macOS 10.15. To silence this warning,
-                    deselect CPython 3.5 by adding "cp35-macosx_x86_64" to your CIBW_SKIP option.
-                    """
-                )
-            )
-            python_configurations = [
-                c for c in python_configurations if not c.identifier.startswith("cp35")
-            ]
-
    return python_configurations


@@ -156,7 +141,7 @@ def install_cpython(version: str, url: str) -> Path:

    # if this version of python isn't installed, get it from python.org and install
    python_package_identifier = f"org.python.Python.PythonFramework-{version}"
-    python_executable = "python3" if version[0] == "3" else "python"
+    python_executable = "python3"
    installation_bin_path = Path(f"/Library/Frameworks/Python.framework/Versions/{version}/bin")

    if python_package_identifier not in installed_system_packages:
@@ -164,24 +149,9 @@ def install_cpython(version: str, url: str) -> Path:
        download(url, Path("/tmp/Python.pkg"))
        # install
        call(["sudo", "installer", "-pkg", "/tmp/Python.pkg", "-target", "/"])
-        # patch open ssl
-        if version == "3.5":
-            open_ssl_patch_url = f"https://github.com/mayeut/patch-macos-python-openssl/releases/download/v1.1.1h/patch-macos-python-{version}-openssl-v1.1.1h.tar.gz"
-            download(open_ssl_patch_url, Path("/tmp/python-patch.tar.gz"))
-            call(
-                [
-                    "sudo",
-                    "tar",
-                    "-C",
-                    f"/Library/Frameworks/Python.framework/Versions/{version}/",
-                    "-xmf",
-                    "/tmp/python-patch.tar.gz",
-                ]
-            )
-
        call(["sudo", str(installation_bin_path / python_executable), str(install_certifi_script)])

-    pip_executable = "pip3" if version[0] == "3" else "pip"
+    pip_executable = "pip3"
    make_symlinks(installation_bin_path, python_executable, pip_executable)

    return installation_bin_path
@@ -197,14 +167,10 @@ def install_pypy(version: str, url: str) -> Path:
        downloaded_tar_bz2 = Path("/tmp") / pypy_tar_bz2
        download(url, downloaded_tar_bz2)
        call(["tar", "-C", "/tmp", "-xf", downloaded_tar_bz2])
-        # Patch PyPy to make sure headers get installed into a venv
-        patch_version = "_27" if version == "2.7" else ""
-        patch_path = resources_dir / f"pypy_venv{patch_version}.patch"
-        call(["patch", "--force", "-p1", "-d", installation_path, "-i", patch_path])

    installation_bin_path = installation_path / "bin"
-    python_executable = "pypy3" if version[0] == "3" else "pypy"
-    pip_executable = "pip3" if version[0] == "3" else "pip"
+    python_executable = "pypy3"
+    pip_executable = "pip3"
    make_symlinks(installation_bin_path, python_executable, pip_executable)

    return installation_bin_path
@@ -214,7 +180,9 @@ def setup_python(
    python_configuration: PythonConfiguration,
    dependency_constraint_flags: Sequence[PathOrStr],
    environment: ParsedEnvironment,
+    build_frontend: BuildFrontend,
 ) -> Dict[str, str]:
+
    implementation_id = python_configuration.identifier.split("-")[0]
    log.step(f"Installing Python {implementation_id}...")

@@ -263,8 +231,29 @@ def setup_python(
        )
        sys.exit(1)

-    # install pip & wheel
-    call(["python", get_pip_script, *dependency_constraint_flags], env=env, cwd="/tmp")
+    # Install pip
+
+    requires_reinstall = not (installation_bin_path / "pip").exists()
+    if requires_reinstall:
+        # maybe pip isn't installed at all. ensurepip resolves that.
+        call(["python", "-m", "ensurepip"], env=env, cwd="/tmp")
+
+    # upgrade pip to the version matching our constraints
+    # if necessary, reinstall it to ensure that it's available on PATH as 'pip'
+    call(
+        [
+            "python",
+            "-m",
+            "pip",
+            "install",
+            "--force-reinstall" if requires_reinstall else "--upgrade",
+            "pip",
+            *dependency_constraint_flags,
+        ],
+        env=env,
+        cwd="/tmp",
+    )
+
    assert (installation_bin_path / "pip").exists()
    call(["which", "pip"], env=env)
    call(["pip", "--version"], env=env)
@@ -279,36 +268,26 @@ def setup_python(
        sys.exit(1)

    # Set MACOSX_DEPLOYMENT_TARGET to 10.9, if the user didn't set it.
-    # CPython 3.5 defaults to 10.6, and pypy defaults to 10.7, causing
-    # inconsistencies if it's left unset.
+    # PyPy defaults to 10.7, causing inconsistencies if it's left unset.
    env.setdefault("MACOSX_DEPLOYMENT_TARGET", "10.9")

    config_is_arm64 = python_configuration.identifier.endswith("arm64")
    config_is_universal2 = python_configuration.identifier.endswith("universal2")

-    if python_configuration.version == "3.5":
-        # Cross-compilation platform override - CPython 3.5 has an
-        # i386/x86_64 version of Python, but we only want a x64_64 build
-        env.setdefault("_PYTHON_HOST_PLATFORM", "macosx-10.9-x86_64")
-        # https://github.com/python/cpython/blob/a5ed2fe0eedefa1649aa93ee74a0bafc8e628a10/Lib/_osx_support.py#L260
-        env.setdefault("ARCHFLAGS", "-arch x86_64")
-
-    if python_configuration.version == "3.9":
-        if python_configuration.identifier.endswith("x86_64"):
-            # even on the macos11.0 Python installer, on the x86_64 side it's
-            # compatible back to 10.9.
-            env.setdefault("_PYTHON_HOST_PLATFORM", "macosx-10.9-x86_64")
-            env.setdefault("ARCHFLAGS", "-arch x86_64")
-        elif config_is_arm64:
+    if python_configuration.version not in {"3.6", "3.7"}:
+        if config_is_arm64:
            # macOS 11 is the first OS with arm64 support, so the wheels
            # have that as a minimum.
            env.setdefault("_PYTHON_HOST_PLATFORM", "macosx-11.0-arm64")
            env.setdefault("ARCHFLAGS", "-arch arm64")
        elif config_is_universal2:
-            if get_macos_version() < (10, 16):
-                # we can do universal2 builds on macos 10.15, but we need to
-                # set ARCHFLAGS otherwise CPython sets it to `-arch x86_64`
-                env.setdefault("ARCHFLAGS", "-arch arm64 -arch x86_64")
+            env.setdefault("_PYTHON_HOST_PLATFORM", "macosx-10.9-universal2")
+            env.setdefault("ARCHFLAGS", "-arch arm64 -arch x86_64")
+        elif python_configuration.identifier.endswith("x86_64"):
+            # even on the macos11.0 Python installer, on the x86_64 side it's
+            # compatible back to 10.9.
+            env.setdefault("_PYTHON_HOST_PLATFORM", "macosx-10.9-x86_64")
+            env.setdefault("ARCHFLAGS", "-arch x86_64")

    building_arm64 = config_is_arm64 or config_is_universal2
    if building_arm64 and get_macos_version() < (10, 16) and "SDKROOT" not in env:
@@ -333,18 +312,33 @@ def setup_python(
            env.setdefault("SDKROOT", arm64_compatible_sdks[0])

    log.step("Installing build tools...")
-    call(
-        [
-            "pip",
-            "install",
-            "--upgrade",
-            "setuptools",
-            "wheel",
-            "delocate",
-            *dependency_constraint_flags,
-        ],
-        env=env,
-    )
+    if build_frontend == "pip":
+        call(
+            [
+                "pip",
+                "install",
+                "--upgrade",
+                "setuptools",
+                "wheel",
+                "delocate",
+                *dependency_constraint_flags,
+            ],
+            env=env,
+        )
+    elif build_frontend == "build":
+        call(
+            [
+                "pip",
+                "install",
+                "--upgrade",
+                "delocate",
+                "build[virtualenv]",
+                *dependency_constraint_flags,
+            ],
+            env=env,
+        )
+    else:
+        assert_never(build_frontend)

    return env

@@ -381,7 +375,12 @@ def build(options: BuildOptions) -> None:
                    options.dependency_constraints.get_for_python_version(config.version),
                ]

-            env = setup_python(config, dependency_constraint_flags, options.environment)
+            env = setup_python(
+                config,
+                dependency_constraint_flags,
+                options.environment,
+                options.build_frontend,
+            )

            if options.before_build:
                log.step("Running before_build...")
@@ -395,20 +394,45 @@ def build(options: BuildOptions) -> None:
                shutil.rmtree(built_wheel_dir)
            built_wheel_dir.mkdir(parents=True)

-            # Path.resolve() is needed. Without it pip wheel may try to fetch package from pypi.org
-            # see https://github.com/pypa/cibuildwheel/pull/369
-            call(
-                [
-                    "pip",
-                    "wheel",
-                    options.package_dir.resolve(),
-                    "--wheel-dir",
-                    built_wheel_dir,
-                    "--no-deps",
-                    *get_build_verbosity_extra_flags(options.build_verbosity),
-                ],
-                env=env,
-            )
+            verbosity_flags = get_build_verbosity_extra_flags(options.build_verbosity)
+
+            if options.build_frontend == "pip":
+                # Path.resolve() is needed. Without it pip wheel may try to fetch package from pypi.org
+                # see https://github.com/pypa/cibuildwheel/pull/369
+                call(
+                    [
+                        "python",
+                        "-m",
+                        "pip",
+                        "wheel",
+                        options.package_dir.resolve(),
+                        f"--wheel-dir={built_wheel_dir}",
+                        "--no-deps",
+                        *verbosity_flags,
+                    ],
+                    env=env,
+                )
+            elif options.build_frontend == "build":
+                config_setting = " ".join(verbosity_flags)
+                build_env = env.copy()
+                if options.dependency_constraints:
+                    constr = options.dependency_constraints.get_for_python_version(config.version)
+                    build_env["PIP_CONSTRAINT"] = constr.as_uri()
+                build_env["VIRTUALENV_PIP"] = get_pip_version(env)
+                call(
+                    [
+                        "python",
+                        "-m",
+                        "build",
+                        options.package_dir,
+                        "--wheel",
+                        f"--outdir={built_wheel_dir}",
+                        f"--config-setting={config_setting}",
+                    ],
+                    env=build_env,
+                )
+            else:
+                assert_never(options.build_frontend)

            built_wheel = next(built_wheel_dir.glob("*.whl"))

@@ -0,0 +1,171 @@
+import os
+from pathlib import Path
+from typing import Any, Dict, List, Mapping, Optional, Set, Tuple, Union
+
+import toml
+
+from .typing import PLATFORMS, TypedDict
+from .util import resources_dir
+
+Setting = Union[Dict[str, str], List[str], str]
+
+
+class TableFmt(TypedDict):
+    item: str
+    sep: str
+
+
+class ConfigOptionError(KeyError):
+    pass
+
+
+def _dig_first(*pairs: Tuple[Mapping[str, Any], str]) -> Setting:
+    """
+    Return the first dict item that matches from pairs of dicts and keys.
+    Final result is will throw a KeyError if missing.
+
+    _dig_first((dict1, "key1"), (dict2, "key2"), ...)
+    """
+    (dict_like, key), *others = pairs
+    return dict_like.get(key, _dig_first(*others)) if others else dict_like[key]
+
+
+class ConfigOptions:
+    """
+    Gets options from the environment, config or defaults, optionally scoped
+    by the platform.
+
+    Example:
+      >>> options = ConfigOptions(package_dir, platform='macos')
+      >>> options('cool-color')
+
+      This will return the value of CIBW_COOL_COLOR_MACOS if it exists,
+      otherwise the value of CIBW_COOL_COLOR, otherwise
+      'tool.cibuildwheel.macos.cool-color' or 'tool.cibuildwheel.cool-color'
+      from pyproject.toml, or from cibuildwheel/resources/defaults.toml. An
+      error is thrown if there are any unexpected keys or sections in
+      tool.cibuildwheel.
+    """
+
+    def __init__(
+        self,
+        package_path: Path,
+        config_file: Optional[str] = None,
+        *,
+        platform: str,
+        disallow: Optional[Dict[str, Set[str]]] = None,
+    ) -> None:
+        self.platform = platform
+        self.disallow = disallow or {}
+
+        # Open defaults.toml, loading both global and platform sections
+        defaults_path = resources_dir / "defaults.toml"
+        self.default_options, self.default_platform_options = self._load_file(defaults_path)
+
+        # load the project config file
+        config_options: Dict[str, Any] = {}
+        config_platform_options: Dict[str, Any] = {}
+
+        if config_file is not None:
+            config_path = Path(config_file.format(package=package_path))
+            config_options, config_platform_options = self._load_file(config_path)
+        else:
+            # load pyproject.toml, if it's available
+            pyproject_toml_path = package_path / "pyproject.toml"
+            if pyproject_toml_path.exists():
+                config_options, config_platform_options = self._load_file(pyproject_toml_path)
+
+        # validate project config
+        for option_name in config_options:
+            if not self._is_valid_global_option(option_name):
+                raise ConfigOptionError(f'Option "{option_name}" not supported in a config file')
+
+        for option_name in config_platform_options:
+            if not self._is_valid_platform_option(option_name):
+                raise ConfigOptionError(
+                    f'Option "{option_name}" not supported in the "{self.platform}" section'
+                )
+
+        self.config_options = config_options
+        self.config_platform_options = config_platform_options
+
+    def _is_valid_global_option(self, name: str) -> bool:
+        """
+        Returns True if an option with this name is allowed in the
+        [tool.cibuildwheel] section of a config file.
+        """
+        allowed_option_names = self.default_options.keys() | PLATFORMS
+
+        return name in allowed_option_names
+
+    def _is_valid_platform_option(self, name: str) -> bool:
+        """
+        Returns True if an option with this name is allowed in the
+        [tool.cibuildwheel.<current-platform>] section of a config file.
+        """
+        disallowed_platform_options = self.disallow.get(self.platform, set())
+        if name in disallowed_platform_options:
+            return False
+
+        allowed_option_names = self.default_options.keys() | self.default_platform_options.keys()
+
+        return name in allowed_option_names
+
+    def _load_file(self, filename: Path) -> Tuple[Dict[str, Any], Dict[str, Any]]:
+        """
+        Load a toml file, returns global and platform as separate dicts.
+        """
+        config = toml.load(filename)
+
+        global_options = config.get("tool", {}).get("cibuildwheel", {})
+        platform_options = global_options.get(self.platform, {})
+
+        return global_options, platform_options
+
+    def __call__(
+        self,
+        name: str,
+        *,
+        env_plat: bool = True,
+        sep: Optional[str] = None,
+        table: Optional[TableFmt] = None,
+    ) -> str:
+        """
+        Get and return the value for the named option from environment,
+        configuration file, or the default. If env_plat is False, then don't
+        accept platform versions of the environment variable. If this is an
+        array it will be merged with "sep" before returning. If it is a table,
+        it will be formatted with "table['item']" using {k} and {v} and merged
+        with "table['sep']".
+        """
+
+        if name not in self.default_options and name not in self.default_platform_options:
+            raise ConfigOptionError(f"{name} must be in cibuildwheel/resources/defaults.toml file")
+
+        # Environment variable form
+        envvar = f"CIBW_{name.upper().replace('-', '_')}"
+        plat_envvar = f"{envvar}_{self.platform.upper()}"
+
+        # get the option from the environment, then the config file, then finally the default.
+        # platform-specific options are preferred, if they're allowed.
+        result = _dig_first(
+            (os.environ if env_plat else {}, plat_envvar),  # type: ignore
+            (os.environ, envvar),
+            (self.config_platform_options, name),
+            (self.config_options, name),
+            (self.default_platform_options, name),
+            (self.default_options, name),
+        )
+
+        if isinstance(result, dict):
+            if table is None:
+                raise ConfigOptionError(f"{name} does not accept a table")
+            return table["sep"].join(table["item"].format(k=k, v=v) for k, v in result.items())
+        elif isinstance(result, list):
+            if sep is None:
+                raise ConfigOptionError(f"{name} does not accept a list")
+            return sep.join(result)
+        elif isinstance(result, int):
+            return str(result)
+        else:
+            return result
@@ -1,69 +1,62 @@
 [linux]
 python_configurations = [
-  { identifier = "cp27-manylinux_x86_64", version = "2.7", path_str = "/opt/python/cp27-cp27m" },
-  { identifier = "cp27-manylinux_x86_64", version = "2.7", path_str = "/opt/python/cp27-cp27mu" },
-  { identifier = "cp35-manylinux_x86_64", version = "3.5", path_str = "/opt/python/cp35-cp35m" },
  { identifier = "cp36-manylinux_x86_64", version = "3.6", path_str = "/opt/python/cp36-cp36m" },
  { identifier = "cp37-manylinux_x86_64", version = "3.7", path_str = "/opt/python/cp37-cp37m" },
  { identifier = "cp38-manylinux_x86_64", version = "3.8", path_str = "/opt/python/cp38-cp38" },
  { identifier = "cp39-manylinux_x86_64", version = "3.9", path_str = "/opt/python/cp39-cp39" },
-  { identifier = "cp27-manylinux_i686", version = "2.7", path_str = "/opt/python/cp27-cp27m" },
-  { identifier = "cp27-manylinux_i686", version = "2.7", path_str = "/opt/python/cp27-cp27mu" },
-  { identifier = "cp35-manylinux_i686", version = "3.5", path_str = "/opt/python/cp35-cp35m" },
+  { identifier = "cp310-manylinux_x86_64", version = "3.10", path_str = "/opt/python/cp310-cp310" },
  { 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" },
  { identifier = "cp39-manylinux_i686", version = "3.9", path_str = "/opt/python/cp39-cp39" },
-  { identifier = "pp27-manylinux_x86_64", version = "2.7", path_str = "/opt/python/pp27-pypy_73" },
-  { identifier = "pp36-manylinux_x86_64", version = "3.6", path_str = "/opt/python/pp36-pypy36_pp73" },
+  { identifier = "cp310-manylinux_i686", version = "3.10", path_str = "/opt/python/cp310-cp310" },
  { identifier = "pp37-manylinux_x86_64", version = "3.7", path_str = "/opt/python/pp37-pypy37_pp73" },
-  { identifier = "cp35-manylinux_aarch64", version = "3.5", path_str = "/opt/python/cp35-cp35m" },
  { identifier = "cp36-manylinux_aarch64", version = "3.6", path_str = "/opt/python/cp36-cp36m" },
  { identifier = "cp37-manylinux_aarch64", version = "3.7", path_str = "/opt/python/cp37-cp37m" },
  { identifier = "cp38-manylinux_aarch64", version = "3.8", path_str = "/opt/python/cp38-cp38" },
  { identifier = "cp39-manylinux_aarch64", version = "3.9", path_str = "/opt/python/cp39-cp39" },
-  { identifier = "cp35-manylinux_ppc64le", version = "3.5", path_str = "/opt/python/cp35-cp35m" },
+  { identifier = "cp310-manylinux_aarch64", version = "3.10", path_str = "/opt/python/cp310-cp310" },
  { 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" },
  { identifier = "cp39-manylinux_ppc64le", version = "3.9", path_str = "/opt/python/cp39-cp39" },
-  { identifier = "cp35-manylinux_s390x", version = "3.5", path_str = "/opt/python/cp35-cp35m" },
+  { identifier = "cp310-manylinux_ppc64le", version = "3.10", path_str = "/opt/python/cp310-cp310" },
  { 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" },
  { identifier = "cp39-manylinux_s390x", version = "3.9", path_str = "/opt/python/cp39-cp39" },
+  { identifier = "cp310-manylinux_s390x", version = "3.10", path_str = "/opt/python/cp310-cp310" },
+  { identifier = "pp37-manylinux_aarch64", version = "3.7", path_str = "/opt/python/pp37-pypy37_pp73" },
+  { identifier = "pp37-manylinux_i686", version = "3.7", path_str = "/opt/python/pp37-pypy37_pp73" },
 ]

 [macos]
 python_configurations = [
-  { identifier = "cp27-macosx_x86_64", version = "2.7", url = "https://www.python.org/ftp/python/2.7.18/python-2.7.18-macosx10.9.pkg" },
-  { identifier = "cp35-macosx_x86_64", version = "3.5", url = "https://www.python.org/ftp/python/3.5.4/python-3.5.4-macosx10.6.pkg" },
  { identifier = "cp36-macosx_x86_64", version = "3.6", url = "https://www.python.org/ftp/python/3.6.8/python-3.6.8-macosx10.9.pkg" },
  { identifier = "cp37-macosx_x86_64", version = "3.7", url = "https://www.python.org/ftp/python/3.7.9/python-3.7.9-macosx10.9.pkg" },
-  { identifier = "cp38-macosx_x86_64", version = "3.8", url = "https://www.python.org/ftp/python/3.8.9/python-3.8.9-macosx10.9.pkg" },
-  { identifier = "cp39-macosx_x86_64", version = "3.9", url = "https://www.python.org/ftp/python/3.9.4/python-3.9.4-macos11.pkg" },
-  { identifier = "cp39-macosx_arm64", version = "3.9", url = "https://www.python.org/ftp/python/3.9.4/python-3.9.4-macos11.pkg" },
-  { identifier = "cp39-macosx_universal2", version = "3.9", url = "https://www.python.org/ftp/python/3.9.4/python-3.9.4-macos11.pkg" },
-  { identifier = "pp27-macosx_x86_64", version = "2.7", url = "https://downloads.python.org/pypy/pypy2.7-v7.3.3-osx64.tar.bz2" },
-  { identifier = "pp36-macosx_x86_64", version = "3.6", url = "https://downloads.python.org/pypy/pypy3.6-v7.3.3-osx64.tar.bz2" },
-  { identifier = "pp37-macosx_x86_64", version = "3.7", url = "https://downloads.python.org/pypy/pypy3.7-v7.3.3-osx64.tar.bz2" },
+  { identifier = "cp38-macosx_x86_64", version = "3.8", url = "https://www.python.org/ftp/python/3.8.10/python-3.8.10-macosx10.9.pkg" },
+  { identifier = "cp38-macosx_arm64", version = "3.8", url = "https://www.python.org/ftp/python/3.8.10/python-3.8.10-macosx10.9.pkg" },
+  { identifier = "cp38-macosx_universal2", version = "3.8", url = "https://www.python.org/ftp/python/3.8.10/python-3.8.10-macosx10.9.pkg" },
+  { identifier = "cp39-macosx_x86_64", version = "3.9", url = "https://www.python.org/ftp/python/3.9.6/python-3.9.6-macos11.pkg" },
+  { identifier = "cp39-macosx_arm64", version = "3.9", url = "https://www.python.org/ftp/python/3.9.6/python-3.9.6-macos11.pkg" },
+  { identifier = "cp39-macosx_universal2", version = "3.9", url = "https://www.python.org/ftp/python/3.9.6/python-3.9.6-macos11.pkg" },
+  { identifier = "cp310-macosx_x86_64", version = "3.10", url = "https://www.python.org/ftp/python/3.10.0/python-3.10.0b4-macos11.pkg" },
+  { identifier = "cp310-macosx_arm64", version = "3.10", url = "https://www.python.org/ftp/python/3.10.0/python-3.10.0b4-macos11.pkg" },
+  { identifier = "cp310-macosx_universal2", version = "3.10", url = "https://www.python.org/ftp/python/3.10.0/python-3.10.0b4-macos11.pkg" },
+  { identifier = "pp37-macosx_x86_64", version = "3.7", url = "https://downloads.python.org/pypy/pypy3.7-v7.3.5-osx64.tar.bz2" },
 ]

 [windows]
 python_configurations = [
-  { identifier = "cp27-win32", version = "2.7.18", arch = "32" },
-  { identifier = "cp27-win_amd64", version = "2.7.18", arch = "64" },
-  { identifier = "cp35-win32", version = "3.5.4", arch = "32" },
-  { identifier = "cp35-win_amd64", version = "3.5.4", arch = "64" },
  { identifier = "cp36-win32", version = "3.6.8", arch = "32" },
  { identifier = "cp36-win_amd64", version = "3.6.8", arch = "64" },
  { identifier = "cp37-win32", version = "3.7.9", arch = "32" },
  { identifier = "cp37-win_amd64", version = "3.7.9", arch = "64" },
-  { identifier = "cp38-win32", version = "3.8.9", arch = "32" },
-  { identifier = "cp38-win_amd64", version = "3.8.9", arch = "64" },
-  { identifier = "cp39-win32", version = "3.9.4", arch = "32" },
-  { identifier = "cp39-win_amd64", version = "3.9.4", arch = "64" },
-  { identifier = "pp27-win32", version = "2.7", arch = "32", url = "https://downloads.python.org/pypy/pypy2.7-v7.3.3-win32.zip" },
-  { identifier = "pp36-win32", version = "3.6", arch = "32", url = "https://downloads.python.org/pypy/pypy3.6-v7.3.3-win32.zip" },
-  { identifier = "pp37-win32", version = "3.7", arch = "32", url = "https://downloads.python.org/pypy/pypy3.7-v7.3.3-win32.zip" },
+  { identifier = "cp38-win32", version = "3.8.10", arch = "32" },
+  { identifier = "cp38-win_amd64", version = "3.8.10", arch = "64" },
+  { identifier = "cp39-win32", version = "3.9.6", arch = "32" },
+  { identifier = "cp39-win_amd64", version = "3.9.6", arch = "64" },
+  { identifier = "cp310-win32", version = "3.10.0-b4", arch = "32" },
+  { identifier = "cp310-win_amd64", version = "3.10.0-b4", arch = "64" },
+  { identifier = "pp37-win_amd64", version = "3.7", arch = "64", url = "https://downloads.python.org/pypy/pypy3.7-v7.3.5-win64.zip" },
 ]
@@ -1,55 +0,0 @@
-#
-# This file is autogenerated by pip-compile
-# To update, run:
-#
-#    bin/update_dependencies.py
-#
-appdirs==1.4.4
-    # via virtualenv
-configparser==4.0.2
-    # via importlib-metadata
-contextlib2==0.6.0.post1
-    # via
-    #   importlib-metadata
-    #   importlib-resources
-delocate==0.8.2
-    # via -r cibuildwheel/resources/constraints.in
-distlib==0.3.1
-    # via virtualenv
-filelock==3.0.12
-    # via virtualenv
-importlib-metadata==2.1.1
-    # via virtualenv
-importlib-resources==3.3.1
-    # via virtualenv
-pathlib2==2.3.5
-    # via
-    #   importlib-metadata
-    #   importlib-resources
-    #   virtualenv
-scandir==1.10.0
-    # via pathlib2
-singledispatch==3.6.1
-    # via importlib-resources
-six==1.15.0
-    # via
-    #   pathlib2
-    #   virtualenv
-typing==3.7.4.3
-    # via importlib-resources
-virtualenv==20.4.3
-    # via -r cibuildwheel/resources/constraints.in
-wheel==0.36.2
-    # via
-    #   -r cibuildwheel/resources/constraints.in
-    #   delocate
-zipp==1.2.0
-    # via
-    #   importlib-metadata
-    #   importlib-resources
-
-# The following packages are considered to be unsafe in a requirements file:
-pip==20.3.4
-    # via -r cibuildwheel/resources/constraints.in
-setuptools==44.1.1
-    # via -r cibuildwheel/resources/constraints.in
@@ -1,36 +0,0 @@
-#
-# This file is autogenerated by pip-compile
-# To update, run:
-#
-#    bin/update_dependencies.py
-#
-appdirs==1.4.4
-    # via virtualenv
-delocate==0.8.2
-    # via -r cibuildwheel/resources/constraints.in
-distlib==0.3.1
-    # via virtualenv
-filelock==3.0.12
-    # via virtualenv
-importlib-metadata==2.1.1
-    # via virtualenv
-importlib-resources==3.2.1
-    # via virtualenv
-six==1.15.0
-    # via virtualenv
-virtualenv==20.4.3
-    # via -r cibuildwheel/resources/constraints.in
-wheel==0.36.2
-    # via
-    #   -r cibuildwheel/resources/constraints.in
-    #   delocate
-zipp==1.2.0
-    # via
-    #   importlib-metadata
-    #   importlib-resources
-
-# The following packages are considered to be unsafe in a requirements file:
-pip==20.3.4
-    # via -r cibuildwheel/resources/constraints.in
-setuptools==50.3.2
-    # via -r cibuildwheel/resources/constraints.in
@@ -1,38 +1,46 @@
 #
-# This file is autogenerated by pip-compile
+# This file is autogenerated by pip-compile with python 3.6
 # To update, run:
 #
 #    bin/update_dependencies.py
 #
-appdirs==1.4.4
+backports.entry-points-selectable==1.1.0
    # via virtualenv
-delocate==0.8.2
+delocate==0.9.0
    # via -r cibuildwheel/resources/constraints.in
-distlib==0.3.1
+distlib==0.3.2
    # via virtualenv
 filelock==3.0.12
    # via virtualenv
-importlib-metadata==3.10.0
+importlib-metadata==4.6.1
+    # via
+    #   backports.entry-points-selectable
+    #   virtualenv
+importlib-resources==5.2.0
    # via virtualenv
-importlib-resources==5.1.2
+platformdirs==2.0.2
    # via virtualenv
-six==1.15.0
-    # via virtualenv
-typing-extensions==3.7.4.3
-    # via importlib-metadata
-virtualenv==20.4.3
+six==1.16.0
+    # via
+    #   delocate
+    #   virtualenv
+typing-extensions==3.10.0.0
+    # via
+    #   delocate
+    #   importlib-metadata
+virtualenv==20.6.0
    # via -r cibuildwheel/resources/constraints.in
 wheel==0.36.2
    # via
    #   -r cibuildwheel/resources/constraints.in
    #   delocate
-zipp==3.4.1
+zipp==3.5.0
    # via
    #   importlib-metadata
    #   importlib-resources

 # The following packages are considered to be unsafe in a requirements file:
-pip==21.0.1
+pip==21.2.1
    # via -r cibuildwheel/resources/constraints.in
-setuptools==54.2.0
+setuptools==57.4.0
    # via -r cibuildwheel/resources/constraints.in
@@ -1,34 +1,42 @@
 #
-# This file is autogenerated by pip-compile
+# This file is autogenerated by pip-compile with python 3.7
 # To update, run:
 #
 #    bin/update_dependencies.py
 #
-appdirs==1.4.4
+backports.entry-points-selectable==1.1.0
    # via virtualenv
-delocate==0.8.2
+delocate==0.9.0
    # via -r cibuildwheel/resources/constraints.in
-distlib==0.3.1
+distlib==0.3.2
    # via virtualenv
 filelock==3.0.12
    # via virtualenv
-importlib-metadata==3.10.0
+importlib-metadata==4.6.1
+    # via
+    #   backports.entry-points-selectable
+    #   virtualenv
+platformdirs==2.0.2
    # via virtualenv
-six==1.15.0
-    # via virtualenv
-typing-extensions==3.7.4.3
-    # via importlib-metadata
-virtualenv==20.4.3
+six==1.16.0
+    # via
+    #   delocate
+    #   virtualenv
+typing-extensions==3.10.0.0
+    # via
+    #   delocate
+    #   importlib-metadata
+virtualenv==20.6.0
    # via -r cibuildwheel/resources/constraints.in
 wheel==0.36.2
    # via
    #   -r cibuildwheel/resources/constraints.in
    #   delocate
-zipp==3.4.1
+zipp==3.5.0
    # via importlib-metadata

 # The following packages are considered to be unsafe in a requirements file:
-pip==21.0.1
+pip==21.2.1
    # via -r cibuildwheel/resources/constraints.in
-setuptools==54.2.0
+setuptools==57.4.0
    # via -r cibuildwheel/resources/constraints.in
@@ -1,20 +1,26 @@
 #
-# This file is autogenerated by pip-compile
+# This file is autogenerated by pip-compile with python 3.8
 # To update, run:
 #
 #    bin/update_dependencies.py
 #
-appdirs==1.4.4
+backports.entry-points-selectable==1.1.0
    # via virtualenv
-delocate==0.8.2
+delocate==0.9.0
    # via -r cibuildwheel/resources/constraints.in
-distlib==0.3.1
+distlib==0.3.2
    # via virtualenv
 filelock==3.0.12
    # via virtualenv
-six==1.15.0
+platformdirs==2.0.2
    # via virtualenv
-virtualenv==20.4.3
+six==1.16.0
+    # via
+    #   delocate
+    #   virtualenv
+typing-extensions==3.10.0.0
+    # via delocate
+virtualenv==20.6.0
    # via -r cibuildwheel/resources/constraints.in
 wheel==0.36.2
    # via
@@ -22,7 +28,7 @@ wheel==0.36.2
    #   delocate

 # The following packages are considered to be unsafe in a requirements file:
-pip==21.0.1
+pip==21.2.1
    # via -r cibuildwheel/resources/constraints.in
-setuptools==54.2.0
+setuptools==57.4.0
    # via -r cibuildwheel/resources/constraints.in
@@ -1,20 +1,26 @@
 #
-# This file is autogenerated by pip-compile
+# This file is autogenerated by pip-compile with python 3.9
 # To update, run:
 #
 #    bin/update_dependencies.py
 #
-appdirs==1.4.4
+backports.entry-points-selectable==1.1.0
    # via virtualenv
-delocate==0.8.2
+delocate==0.9.0
    # via -r cibuildwheel/resources/constraints.in
-distlib==0.3.1
+distlib==0.3.2
    # via virtualenv
 filelock==3.0.12
    # via virtualenv
-six==1.15.0
+platformdirs==2.0.2
    # via virtualenv
-virtualenv==20.4.3
+six==1.16.0
+    # via
+    #   delocate
+    #   virtualenv
+typing-extensions==3.10.0.0
+    # via delocate
+virtualenv==20.6.0
    # via -r cibuildwheel/resources/constraints.in
 wheel==0.36.2
    # via
@@ -22,7 +28,7 @@ wheel==0.36.2
    #   delocate

 # The following packages are considered to be unsafe in a requirements file:
-pip==21.0.1
+pip==21.2.1
    # via -r cibuildwheel/resources/constraints.in
-setuptools==54.2.0
+setuptools==57.4.0
    # via -r cibuildwheel/resources/constraints.in
@@ -1,20 +1,26 @@
 #
-# This file is autogenerated by pip-compile
+# This file is autogenerated by pip-compile with python 3.9
 # To update, run:
 #
 #    bin/update_dependencies.py
 #
-appdirs==1.4.4
+backports.entry-points-selectable==1.1.0
    # via virtualenv
-delocate==0.8.2
+delocate==0.9.0
    # via -r cibuildwheel/resources/constraints.in
-distlib==0.3.1
+distlib==0.3.2
    # via virtualenv
 filelock==3.0.12
    # via virtualenv
-six==1.15.0
+platformdirs==2.0.2
    # via virtualenv
-virtualenv==20.4.3
+six==1.16.0
+    # via
+    #   delocate
+    #   virtualenv
+typing-extensions==3.10.0.0
+    # via delocate
+virtualenv==20.6.0
    # via -r cibuildwheel/resources/constraints.in
 wheel==0.36.2
    # via
@@ -22,7 +28,7 @@ wheel==0.36.2
    #   delocate

 # The following packages are considered to be unsafe in a requirements file:
-pip==21.0.1
+pip==21.2.1
    # via -r cibuildwheel/resources/constraints.in
-setuptools==54.2.0
+setuptools==57.4.0
    # via -r cibuildwheel/resources/constraints.in
@@ -0,0 +1,40 @@
+[tool.cibuildwheel]
+build = "*"
+skip = ""
+test-skip = ""
+
+archs = ["auto"]
+build-frontend = "pip"
+dependency-versions = "pinned"
+environment = {}
+build-verbosity = ""
+
+before-all = ""
+before-build = ""
+repair-wheel-command = ""
+
+test-command = ""
+before-test = ""
+test-requires = []
+test-extras = []
+
+manylinux-x86_64-image = "manylinux2010"
+manylinux-i686-image = "manylinux2010"
+manylinux-aarch64-image = "manylinux2014"
+manylinux-ppc64le-image = "manylinux2014"
+manylinux-s390x-image = "manylinux2014"
+manylinux-pypy_x86_64-image = "manylinux2010"
+manylinux-pypy_i686-image = "manylinux2010"
+manylinux-pypy_aarch64-image = "manylinux2014"
+
+
+[tool.cibuildwheel.linux]
+repair-wheel-command = "auditwheel repair -w {dest_dir} {wheel}"
+
+[tool.cibuildwheel.macos]
+repair-wheel-command = [
+  "delocate-listdeps {wheel}",
+  "delocate-wheel --require-archs {delocate_archs} -w {dest_dir} {wheel}",
+]
+
+[tool.cibuildwheel.windows]
@@ -24,9 +24,6 @@ STAT_0o775 = (
    | stat.S_IXOTH
 )

-if sys.version_info[0] == 2:
-    FileNotFoundError = OSError
-

 def main():
    openssl_dir, openssl_cafile = os.path.split(ssl.get_default_verify_paths().openssl_cafile)
@@ -1,26 +1,38 @@
 [x86_64]
-manylinux1 = quay.io/pypa/manylinux1_x86_64:2021-05-05-b64d921
-manylinux2010 = quay.io/pypa/manylinux2010_x86_64:2021-02-06-3d322a5
-manylinux2014 = quay.io/pypa/manylinux2014_x86_64:2021-05-01-28d233a
-manylinux_2_24 = quay.io/pypa/manylinux_2_24_x86_64:2021-05-01-28d233a
+manylinux1 = quay.io/pypa/manylinux1_x86_64:2021-07-25-0f995ee
+manylinux2010 = quay.io/pypa/manylinux2010_x86_64:2021-07-25-cfe8a6c
+manylinux2014 = quay.io/pypa/manylinux2014_x86_64:2021-07-25-cfe8a6c
+manylinux_2_24 = quay.io/pypa/manylinux_2_24_x86_64:2021-07-25-cfe8a6c

 [i686]
-manylinux1 = quay.io/pypa/manylinux1_i686:2021-05-05-b64d921
-manylinux2010 = quay.io/pypa/manylinux2010_i686:2021-02-06-3d322a5
-manylinux2014 = quay.io/pypa/manylinux2014_i686:2021-05-01-28d233a
-manylinux_2_24 = quay.io/pypa/manylinux_2_24_i686:2021-05-01-28d233a
+manylinux1 = quay.io/pypa/manylinux1_i686:2021-07-25-0f995ee
+manylinux2010 = quay.io/pypa/manylinux2010_i686:2021-07-25-cfe8a6c
+manylinux2014 = quay.io/pypa/manylinux2014_i686:2021-07-25-cfe8a6c
+manylinux_2_24 = quay.io/pypa/manylinux_2_24_i686:2021-07-25-cfe8a6c

 [pypy_x86_64]
-manylinux2010 = pypywheels/manylinux2010-pypy_x86_64:2020-12-11-f1e0e80
+manylinux2010 = quay.io/pypa/manylinux2010_x86_64:2021-07-25-cfe8a6c
+manylinux2014 = quay.io/pypa/manylinux2014_x86_64:2021-07-25-cfe8a6c
+manylinux_2_24 = quay.io/pypa/manylinux_2_24_x86_64:2021-07-25-cfe8a6c
+
+[pypy_i686]
+manylinux2010 = quay.io/pypa/manylinux2010_i686:2021-07-25-cfe8a6c
+manylinux2014 = quay.io/pypa/manylinux2014_i686:2021-07-25-cfe8a6c
+manylinux_2_24 = quay.io/pypa/manylinux_2_24_i686:2021-07-25-cfe8a6c

 [aarch64]
-manylinux2014 = quay.io/pypa/manylinux2014_aarch64:2021-05-01-28d233a
-manylinux_2_24 = quay.io/pypa/manylinux_2_24_aarch64:2021-05-01-28d233a
+manylinux2014 = quay.io/pypa/manylinux2014_aarch64:2021-07-25-cfe8a6c
+manylinux_2_24 = quay.io/pypa/manylinux_2_24_aarch64:2021-07-25-cfe8a6c

 [ppc64le]
-manylinux2014 = quay.io/pypa/manylinux2014_ppc64le:2021-05-01-28d233a
-manylinux_2_24 = quay.io/pypa/manylinux_2_24_ppc64le:2021-05-01-28d233a
+manylinux2014 = quay.io/pypa/manylinux2014_ppc64le:2021-07-25-cfe8a6c
+manylinux_2_24 = quay.io/pypa/manylinux_2_24_ppc64le:2021-07-25-cfe8a6c

 [s390x]
-manylinux2014 = quay.io/pypa/manylinux2014_s390x:2021-05-01-28d233a
-manylinux_2_24 = quay.io/pypa/manylinux_2_24_s390x:2021-05-01-28d233a
+manylinux2014 = quay.io/pypa/manylinux2014_s390x:2021-07-25-cfe8a6c
+manylinux_2_24 = quay.io/pypa/manylinux_2_24_s390x:2021-07-25-cfe8a6c
+
+[pypy_aarch64]
+manylinux2014 = quay.io/pypa/manylinux2014_aarch64:2021-07-25-cfe8a6c
+manylinux_2_24 = quay.io/pypa/manylinux_2_24_aarch64:2021-07-25-cfe8a6c
+
@@ -1,36 +0,0 @@
-diff --git a/lib-python/3/sysconfig.py b/lib-python/3/sysconfig.py
-index 0d08cde66b4150e1772c13fdc6fe34d079c2b10d..30c77d165a2505d98bc7660ff0cc3b728f56c682 100644
--- a/lib-python/3/sysconfig.py
-+++ b/lib-python/3/sysconfig.py
-@@ -618,9 +618,6 @@ def get_config_vars(*args):
-             import _osx_support
-             _osx_support.customize_config_vars(_CONFIG_VARS)
-
-        _CONFIG_VARS['INCLUDEPY'] = os.path.join(_CONFIG_VARS['prefix'],
-                                                 'include')
-
-     if args:
-         vals = []
-         for name in args:
-diff --git a/lib_pypy/_sysconfigdata.py b/lib_pypy/_sysconfigdata.py
-index f1cca41a4b7553819bb1a2a63af1c1a9b8591ce9..a34216e8e12b82abd72fabdd7793b3e8bb19bbcf 100644
--- a/lib_pypy/_sysconfigdata.py
-+++ b/lib_pypy/_sysconfigdata.py
-@@ -5,6 +5,7 @@ from distutils.spawn import find_executable
-
- so_ext = _imp.extension_suffixes()[0]
-
-+mybase = os.path.dirname(os.path.dirname(__file__))
-
- build_time_vars = {
-     # SOABI is PEP 3149 compliant, but CPython3 has so_ext.split('.')[1]
-@@ -25,7 +26,8 @@ build_time_vars = {
-     'AR': "ar",
-     'ARFLAGS': "rc",
-     'EXE': "",
-    'LIBDIR': os.path.join(sys.prefix, 'bin'),
-+    'LIBDIR': os.path.join(mybase, 'lib'),
-+    'INCLUDEPY': os.path.join(mybase, 'include'),
- }
-
- if find_executable("gcc"):
@@ -1,27 +0,0 @@
--- a/lib-python/2.7/sysconfig.py
-+++ b/lib-python/2.7/sysconfig.py
-@@ -553,9 +553,6 @@ def get_config_vars(*args):
-             if type_ == imp.C_EXTENSION:
-                 _CONFIG_VARS['SOABI'] = suffix.split('.')[1]
-                 break
-        _CONFIG_VARS['INCLUDEPY'] = os.path.join(_CONFIG_VARS['prefix'],
-                                                 'include')
-
-     if args:
-         vals = []
-         for name in args:
--- a/lib_pypy/_sysconfigdata.py
-+++ b/lib_pypy/_sysconfigdata.py
-@@ -1,5 +1,11 @@
-import imp
-+import imp, os
-+
-+mybase = os.path.dirname(os.path.dirname(__file__))
-
- build_time_vars = {
-     "SO": [s[0] for s in imp.get_suffixes() if s[2] == imp.C_EXTENSION][0]
- }
-+
-+build_time_vars['LIBDIR'] = os.path.join(mybase, 'lib')
-+build_time_vars['INCLUDEPY'] = os.path.join(mybase, 'include')
-+
@@ -4,6 +4,8 @@ import itertools
 import os
 import re
 import ssl
+import subprocess
+import sys
 import textwrap
 import time
 import urllib.request
@@ -20,13 +22,14 @@ from packaging.version import Version

 from .architecture import Architecture
 from .environment import ParsedEnvironment
-from .typing import PathOrStr, PlatformName
+from .typing import Literal, PathOrStr, PlatformName

 resources_dir = Path(__file__).parent / "resources"

-get_pip_script = resources_dir / "get-pip.py"
 install_certifi_script = resources_dir / "install_certifi.py"

+BuildFrontend = Literal["pip", "build"]
+

 def prepare_command(command: str, **kwargs: PathOrStr) -> str:
    """
@@ -59,15 +62,25 @@ class IdentifierSelector:
    This class holds a set of build/skip patterns. You call an instance with a
    build identifier, and it returns True if that identifier should be
    included. Only call this on valid identifiers, ones that have at least 2
-    numeric digits before the first dash.
+    numeric digits before the first dash. If a pre-release version X.Y is present,
+    you can filter it with prerelease="XY".
    """

+    # a pattern that skips prerelease versions, when include_prereleases is False.
+    PRERELEASE_SKIP = "cp310-*"
+
    def __init__(
-        self, *, build_config: str, skip_config: str, requires_python: Optional[SpecifierSet] = None
+        self,
+        *,
+        build_config: str,
+        skip_config: str,
+        requires_python: Optional[SpecifierSet] = None,
+        prerelease_pythons: bool = False,
    ):
        self.build_patterns = build_config.split()
        self.skip_patterns = skip_config.split()
        self.requires_python = requires_python
+        self.prerelease_pythons = prerelease_pythons

    def __call__(self, build_id: str) -> bool:
        # Filter build selectors by python_requires if set
@@ -82,17 +95,33 @@ class IdentifierSelector:
        build_patterns = itertools.chain.from_iterable(
            bracex.expand(p) for p in self.build_patterns
        )
-        skip_patterns = itertools.chain.from_iterable(bracex.expand(p) for p in self.skip_patterns)
+
+        unexpanded_skip_patterns = self.skip_patterns.copy()
+
+        if not self.prerelease_pythons:
+            # filter out the prerelease pythons, alongside the user-defined
+            # skip patterns
+            unexpanded_skip_patterns += BuildSelector.PRERELEASE_SKIP.split()
+
+        skip_patterns = itertools.chain.from_iterable(
+            bracex.expand(p) for p in unexpanded_skip_patterns
+        )

        build: bool = any(fnmatch.fnmatch(build_id, pat) for pat in build_patterns)
        skip: bool = any(fnmatch.fnmatch(build_id, pat) for pat in skip_patterns)
        return build and not skip

    def __repr__(self) -> str:
-        if not self.skip_patterns:
-            return f'{self.__class__.__name__}({" ".join(self.build_patterns)!r})'
-        else:
-            return f'{self.__class__.__name__}({" ".join(self.build_patterns)!r} - {" ".join(self.skip_patterns)!r})'
+        result = f'{self.__class__.__name__}(build_config={" ".join(self.build_patterns)!r}'
+
+        if self.skip_patterns:
+            result += f', skip_config={" ".join(self.skip_patterns)!r}'
+        if self.prerelease_pythons:
+            result += ", prerelease_pythons=True"
+
+        result += ")"
+
+        return result


 class BuildSelector(IdentifierSelector):
@@ -115,8 +144,8 @@ class Unbuffered:
        self.stream.write(data)
        self.stream.flush()

-    def writelines(self, datas):  # type: ignore
-        self.stream.writelines(datas)
+    def writelines(self, data):  # type: ignore
+        self.stream.writelines(data)
        self.stream.flush()

    def __getattr__(self, attr):  # type: ignore
@@ -163,7 +192,7 @@ class DependencyConstraints:
        version_parts = version.split(".")

        # try to find a version-specific dependency file e.g. if
-        # ./constraints.txt is the base, look for ./constraints-python27.txt
+        # ./constraints.txt is the base, look for ./constraints-python36.txt
        specific_stem = self.base_file_path.stem + f"-python{version_parts[0]}{version_parts[1]}"
        specific_name = specific_stem + self.base_file_path.suffix
        specific_file_path = self.base_file_path.with_name(specific_name)
@@ -193,6 +222,7 @@ class BuildOptions(NamedTuple):
    test_requires: List[str]
    test_extras: str
    build_verbosity: int
+    build_frontend: BuildFrontend


 class NonPlatformWheelError(Exception):
@@ -275,3 +305,18 @@ def print_new_wheels(msg: str, output_dir: Path) -> Iterator[None]:
    s = time.time() - start_time
    m = s / 60
    print(msg.format(n=n, s=s, m=m), *sorted(f"  {f.name}" for f in new_contents), sep="\n")
+
+
+def get_pip_version(env: Dict[str, str]) -> str:
+    # we use shell=True here for windows, even though we don't need a shell due to a bug
+    # https://bugs.python.org/issue8557
+    shell = sys.platform.startswith("win")
+    versions_output_text = subprocess.check_output(
+        ["python", "-m", "pip", "freeze", "--all"], universal_newlines=True, shell=shell, env=env
+    )
+    (pip_version,) = (
+        version[5:]
+        for version in versions_output_text.strip().splitlines()
+        if version.startswith("pip==")
+    )
+    return pip_version
@@ -7,28 +7,27 @@ from pathlib import Path
 from typing import Dict, List, NamedTuple, Optional, Sequence, Set
 from zipfile import ZipFile

-import toml
-
 from .architecture import Architecture
 from .environment import ParsedEnvironment
 from .logger import log
-from .typing import PathOrStr
+from .typing import PathOrStr, assert_never
 from .util import (
+    BuildFrontend,
    BuildOptions,
    BuildSelector,
    NonPlatformWheelError,
    download,
    get_build_verbosity_extra_flags,
-    get_pip_script,
+    get_pip_version,
    prepare_command,
    read_python_configs,
 )

-IS_RUNNING_ON_AZURE = Path("C:\\hostedtoolcache").exists()
+CIBW_INSTALL_PATH = Path("C:\\cibw")


 def call(
-    args: Sequence[PathOrStr], env: Optional[Dict[str, str]] = None, cwd: Optional[str] = None
+    args: Sequence[PathOrStr], env: Optional[Dict[str, str]] = None, cwd: Optional[PathOrStr] = None
 ) -> None:
    print("+ " + " ".join(str(a) for a in args))
    # we use shell=True here, even though we don't need a shell due to a bug
@@ -36,13 +35,15 @@ def call(
    subprocess.run([str(a) for a in args], env=env, cwd=cwd, shell=True, check=True)


-def shell(command: str, env: Optional[Dict[str, str]] = None, cwd: Optional[str] = None) -> None:
+def shell(
+    command: str, env: Optional[Dict[str, str]] = None, cwd: Optional[PathOrStr] = None
+) -> None:
    print(f"+ {command}")
    subprocess.run(command, env=env, cwd=cwd, shell=True, check=True)


 def get_nuget_args(version: str, arch: str) -> List[str]:
-    python_name = "python" if version[0] == "3" else "python2"
+    python_name = "python"
    if arch == "32":
        python_name += "x86"
    return [
@@ -52,7 +53,7 @@ def get_nuget_args(version: str, arch: str) -> List[str]:
        "-FallbackSource",
        "https://api.nuget.org/v3/index.json",
        "-OutputDirectory",
-        "C:\\cibw\\python",
+        str(CIBW_INSTALL_PATH / "python"),
    ]


@@ -77,13 +78,6 @@ def get_python_configurations(
        "64": Architecture.AMD64,
    }

-    # Only supported with custom compiler, since MS removed the 2008 compiler download
-    custom_compiler = os.environ.get("DISTUTILS_USE_SDK") and os.environ.get("MSSdk")
-    if not custom_compiler:
-        python_configurations = [
-            c for c in python_configurations if not c.version.startswith("2.7")
-        ]
-
    # skip builds as required
    python_configurations = [
        c
@@ -107,19 +101,18 @@ def install_cpython(version: str, arch: str, nuget: Path) -> Path:


 def install_pypy(version: str, arch: str, url: str) -> Path:
-    assert arch == "32"
+    assert arch == "64" and "win64" in url
    # Inside the PyPy zip file is a directory with the same name
    zip_filename = url.rsplit("/", 1)[-1]
    extension = ".zip"
    assert zip_filename.endswith(extension)
-    installation_path = Path("C:\\cibw") / zip_filename[: -len(extension)]
+    installation_path = CIBW_INSTALL_PATH / zip_filename[: -len(extension)]
    if not installation_path.exists():
-        pypy_zip = Path("C:\\cibw") / zip_filename
+        pypy_zip = CIBW_INSTALL_PATH / zip_filename
        download(url, pypy_zip)
        # Extract to the parent directory because the zip file still contains a directory
        extract_zip(pypy_zip, installation_path.parent)
-        pypy_exe = "pypy3.exe" if version[0] == "3" else "pypy.exe"
-        (installation_path / "python.exe").symlink_to(installation_path / pypy_exe)
+        (installation_path / "python.exe").symlink_to(installation_path / "pypy3.exe")
    return installation_path


@@ -127,8 +120,10 @@ def setup_python(
    python_configuration: PythonConfiguration,
    dependency_constraint_flags: Sequence[PathOrStr],
    environment: ParsedEnvironment,
+    build_frontend: BuildFrontend,
 ) -> Dict[str, str]:
-    nuget = Path("C:\\cibw\\nuget.exe")
+
+    nuget = CIBW_INSTALL_PATH / "nuget.exe"
    if not nuget.exists():
        log.step("Downloading nuget...")
        download("https://dist.nuget.org/win-x86-commandline/latest/nuget.exe", nuget)
@@ -186,9 +181,31 @@ def setup_python(
        )
        sys.exit(1)

-    # make sure pip is installed
-    if not (installation_path / "Scripts" / "pip.exe").exists():
-        call(["python", get_pip_script, *dependency_constraint_flags], env=env, cwd="C:\\cibw")
+    log.step("Installing build tools...")
+
+    # Install pip
+
+    requires_reinstall = not (installation_path / "Scripts" / "pip.exe").exists()
+    if requires_reinstall:
+        # maybe pip isn't installed at all. ensurepip resolves that.
+        call(["python", "-m", "ensurepip"], env=env, cwd=CIBW_INSTALL_PATH)
+
+    # upgrade pip to the version matching our constraints
+    # if necessary, reinstall it to ensure that it's available on PATH as 'pip.exe'
+    call(
+        [
+            "python",
+            "-m",
+            "pip",
+            "install",
+            "--force-reinstall" if requires_reinstall else "--upgrade",
+            "pip",
+            *dependency_constraint_flags,
+        ],
+        env=env,
+        cwd=CIBW_INSTALL_PATH,
+    )
+
    assert (installation_path / "Scripts" / "pip.exe").exists()
    where_pip = (
        subprocess.run(
@@ -204,49 +221,31 @@ def setup_python(
        )
        sys.exit(1)

-    log.step("Installing build tools...")
-
-    call(
-        ["python", "-m", "pip", "install", "--upgrade", "pip", *dependency_constraint_flags],
-        env=env,
-    )
    call(["pip", "--version"], env=env)
-    call(
-        ["pip", "install", "--upgrade", "setuptools", "wheel", *dependency_constraint_flags],
-        env=env,
-    )
+
+    if build_frontend == "pip":
+        call(
+            [
+                "pip",
+                "install",
+                "--upgrade",
+                "setuptools",
+                "wheel",
+                *dependency_constraint_flags,
+            ],
+            env=env,
+        )
+    elif build_frontend == "build":
+        call(
+            ["pip", "install", "--upgrade", "build[virtualenv]", *dependency_constraint_flags],
+            env=env,
+        )
+    else:
+        assert_never(build_frontend)

    return env


-def pep_518_cp35_workaround(package_dir: Path, env: Dict[str, str]) -> None:
-    """
-    Python 3.5 PEP 518 hack (see https://github.com/pypa/pip/issues/8392#issuecomment-639563494)
-    Basically, nuget's Python is an embedded Python distribution, which is not supported by pip.
-    Before version 3.6, there was no way to disable the "embedded" behavior, including the ignoring
-    of environment variables, including the ones pip uses to setup PEP 518 builds.
-
-    The fix here is as suggested in that issue; we manually setup the PEP 518 requirements. Since we
-    are in a fresh environment (except for pinned cibuildweel dependencies), the build is already
-    mostly "isolated".
-    """
-
-    pyproject_path = package_dir / "pyproject.toml"
-
-    if pyproject_path.exists():
-        data = toml.load(pyproject_path)
-        requirements = data["build-system"].get("requires", []) if "build-system" in data else []
-
-        if requirements:
-            log.step("Performing PEP518 workaround...")
-            with tempfile.TemporaryDirectory() as d:
-                reqfile = Path(d) / "requirements.txt"
-                with reqfile.open("w") as f:
-                    for r in requirements:
-                        print(r, file=f)
-                call(["pip", "install", "-r", reqfile], env=env)
-
-
 def build(options: BuildOptions) -> None:
    temp_dir = Path(tempfile.mkdtemp(prefix="cibuildwheel"))
    built_wheel_dir = temp_dir / "built_wheel"
@@ -276,7 +275,12 @@ def build(options: BuildOptions) -> None:
                ]

            # install Python
-            env = setup_python(config, dependency_constraint_flags, options.environment)
+            env = setup_python(
+                config,
+                dependency_constraint_flags,
+                options.environment,
+                options.build_frontend,
+            )

            # run the before_build command
            if options.before_build:
@@ -286,29 +290,64 @@ def build(options: BuildOptions) -> None:
                )
                shell(before_build_prepared, env=env)

-            # activate the PEP 518 patch if on Windows Python 3.5
-            # (will only have an effect if PEP 517 builds are used):
-            if config.version.startswith("3.5"):
-                pep_518_cp35_workaround(options.package_dir, env)
-
            log.step("Building wheel...")
            if built_wheel_dir.exists():
                shutil.rmtree(built_wheel_dir)
            built_wheel_dir.mkdir(parents=True)
-            # Path.resolve() is needed. Without it pip wheel may try to fetch package from pypi.org
-            # see https://github.com/pypa/cibuildwheel/pull/369
-            call(
-                [
-                    "pip",
-                    "wheel",
-                    options.package_dir.resolve(),
-                    "-w",
-                    built_wheel_dir,
-                    "--no-deps",
-                    *get_build_verbosity_extra_flags(options.build_verbosity),
-                ],
-                env=env,
-            )
+
+            verbosity_flags = get_build_verbosity_extra_flags(options.build_verbosity)
+
+            if options.build_frontend == "pip":
+                # Path.resolve() is needed. Without it pip wheel may try to fetch package from pypi.org
+                # see https://github.com/pypa/cibuildwheel/pull/369
+                call(
+                    [
+                        "python",
+                        "-m",
+                        "pip",
+                        "wheel",
+                        options.package_dir.resolve(),
+                        f"--wheel-dir={built_wheel_dir}",
+                        "--no-deps",
+                        *get_build_verbosity_extra_flags(options.build_verbosity),
+                    ],
+                    env=env,
+                )
+            elif options.build_frontend == "build":
+                config_setting = " ".join(verbosity_flags)
+                build_env = env.copy()
+                if options.dependency_constraints:
+                    constraints_path = options.dependency_constraints.get_for_python_version(
+                        config.version
+                    )
+                    # Bug in pip <= 21.1.3 - we can't have a space in the
+                    # constraints file, and pip doesn't support drive letters
+                    # in uhi.  After probably pip 21.2, we can use uri. For
+                    # now, use a temporary file.
+                    if " " in str(constraints_path):
+                        tmp_file = tempfile.NamedTemporaryFile(
+                            "w", suffix="constraints.txt", delete=False, dir=CIBW_INSTALL_PATH
+                        )
+                        with tmp_file as new_constraints_file, open(constraints_path) as f:
+                            new_constraints_file.write(f.read())
+                            constraints_path = Path(new_constraints_file.name)
+
+                    build_env["PIP_CONSTRAINT"] = str(constraints_path)
+                    build_env["VIRTUALENV_PIP"] = get_pip_version(env)
+                    call(
+                        [
+                            "python",
+                            "-m",
+                            "build",
+                            options.package_dir,
+                            "--wheel",
+                            f"--outdir={built_wheel_dir}",
+                            f"--config-setting={config_setting}",
+                        ],
+                        env=build_env,
+                    )
+            else:
+                assert_never(options.build_frontend)

            built_wheel = next(built_wheel_dir.glob("*.whl"))

@@ -20,7 +20,7 @@ Design Goals

 Other notes:

- The platforms are very similar, until they're not. I'd rather have straight-forward code than totally DRY code, so let's keep airy platfrom abstractions to a minimum.
+- The platforms are very similar, until they're not. I'd rather have straight-forward code than totally DRY code, so let's keep airy platform abstractions to a minimum.
 - I might want to break the options into a shared config file one day, so that config is more easily shared. That has motivated some of the design decisions.

 ### cibuildwheel's relationship with build errors
@@ -34,11 +34,32 @@ So, if we can, I'd like to improve the experience on errors as well. In [this](h
 Maintainer notes
 ----------------

+### Nox support
+
+Most developer tasks have a nox interface. This allows you to very simply run tasks without worrying about setting up a development environment (as shown below). This is a slower than setting up a development environment and reusing it, but has the (important) benefit of being highly reproducible; an earlier run does not affect a current run, or anything else on your machine.
+
+Install [nox](https://nox.thea.codes); homebrew is recommend on macOS, otherwise, pipx is a great choice - in fact, you can use `pipx run nox` and avoid installing completely.
+
+You can see a list of sessions by typing `nox -l`; here are a few common ones:
+
+```console
+nox -s lint          # Run the linters (default)
+nox -s tests         # Run the tests   (default)
+nox -s docs -- serve # Build and serve the documentation
+nox -s build         # Make SDist and wheel
+```
+
+More advanced users can run the update scripts. `update_pins` should work directly, but `update_constraints` needs all versions of Python installed. If you don't want to do that locally, a fast way to run it to use docker to run nox:
+
+```console
+docker run --rm -itv $PWD:/src -w /src quay.io/pypa/manylinux_2_24_x86_64:latest pipx run nox -s update_constraints
+```
+
 ### Local testing

 You should run:

-```python
+```console
 python3 -m venv venv
 . venv/bin/activate
 pip install -e .[dev]
@@ -73,8 +94,6 @@ This has been moved to using docker, so you only need the following instructions
 The dependency update script in the next section requires multiple python versions installed. One way to do this is to use `pyenv`:

 ```bash
-pyenv install 2.7.18
-pyenv install 3.5.9
 pyenv install 3.6.11
 pyenv install 3.7.8
 # Optionally add 3.8 and make it the local version;
@@ -84,9 +103,6 @@ pyenv install 3.7.8
 Then, you need to make the required virtual environments:

 ```bash
-$(pyenv prefix 2.7.18)/bin/python -m pip install virtualenv
-$(pyenv prefix 2.7.18)/bin/python -m virtualenv env27
-$(pyenv prefix 3.5.9)/bin/python -m venv env35
 $(pyenv prefix 3.6.11)/bin/python -m venv env36
 $(pyenv prefix 3.7.8)/bin/python -m venv env37
 ```
@@ -5,10 +5,6 @@ title: Modern C++ standards
 Building Python wheels with modern C++ standards (C++11 and later) requires a few tricks.


-## Python 2.7 and C++17
-
-The Python 2.7 header files use the `register` keyword, which is [reserved and unused from C+17 onwards](https://en.cppreference.com/w/cpp/keyword/register). Compiling a wheel for Python 2.7 with the C++17 standard is still possible to allow usage of `register` using proper flag `-Wno-register` for gcc/clang and `/wd5033` for MSVC.
-
 ## manylinux1 and C++14
 The default `manylinux1` image (based on CentOS 5) contains a version of GCC and libstdc++ that only supports C++11 and earlier standards. There are however ways to compile wheels with the C++14 standard (and later): https://github.com/pypa/manylinux/issues/118

@@ -27,45 +23,3 @@ To get C++17 support, Xcode 9.3+ is needed, requiring at least macOS 10.13 on th
 However, if only C++17 compiler and standard template library (STL) features are used (not needing a C++17 runtime) it might be possible to set `MACOSX_DEPLOYMENT_TARGET` to a lower value, such as `"10.9"`. To find out if this is the case, try compiling and running with a lower `MACOSX_DEPLOYMENT_TARGET`: if C++17 features are used that require a more recent deployment target, building the wheel should fail.

 For more details see https://en.cppreference.com/w/cpp/compiler_support, https://en.wikipedia.org/wiki/Xcode, and https://xcodereleases.com/: Xcode 10 needs macOS 10.13 and Xcode 11 needs macOS 10.14.
-
-## Windows and Python 2.7
-
-In previous years, Microsoft distributed a compiler toolchain called 'Visual C++ for Python 2.7', which was a distribution of MSVC 2008 that was created to make it easier to build Python 2.7 extensions on Windows, because it was fully compatible with the toolchain that built Python 2.7.
-
-This toolchain does not support modern C++ standards (i.e., C++11 and later). And it is hard to find this toolchain these days, since Microsoft removed the download for the required Visual Studio 2008 needed to build a native extension in April, 2021. So, by default, cibuildwheel does not attempt to build Python 2.7 extensions on Windows.
-
-There is an optional workaround, though: the pybind11 project argues and shows that it is [possible to compile Python 2.7 extension with a newer compiler](https://pybind11.readthedocs.io/en/stable/faq.html#working-with-ancient-visual-studio-2008-builds-on-windows) and has an example project showing how to do this: https://github.com/pybind/python_example. The main catch is that a user might need to install [a newer "Microsoft Visual C++ Redistributable"](https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads), since the newer C++ standard library's binaries are not included by default with the Python 2.7 installation.
-
-Forcing `distutils` or `setuptools` to use a more recent version of MSVC that supports modern C++ can be done in the following way:
-
-1. Set the environment variables `DISTUTILS_USE_SDK=1` and `MSSdk=1`. These two environment variables will tell `distutils`/`setuptools` to not search and set up a build environment that uses Visual C++ for Python 2.7 (aka. MSVC 9).
-2. Set up the build Visual Studio build environment you want to use, making sure that e.g. `PATH` contains `cl`, `link`, etc.
-    - Usually, this can be done through `vcvarsall.bat x86` or `vcvarsall.bat x64`. The exact location of this file depends on the installation, but the default path for VS 2019 Community (e.g. used in AppVeyor's `Visual Studio 2019` image) is `C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvarsall.bat`. **Note**: `vcvarsall.bat` changes the environment variables, so this cannot be run in a subprocess/subshell and consequently running `vsvarsall.bat` in `CIBW_BEFORE_BUILD` does not have any effect.
-    - In Azure Pipelines, [a `VSBuild` task is available](https://docs.microsoft.com/en-us/azure/devops/pipelines/tasks/build/visual-studio-build)
-    - In GitHub Actions, the default shell is powershell, so you'll need to use `shell: cmd` to source a `.bat` file, and the directory is `"C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC\Auxiliary\Build\vcvarsall.bat"`. Or you can use an action, such as the [`ilammy/msvc-dev-cmd@v1`](https://github.com/ilammy/msvc-dev-cmd) action to setup the environment (see example below).
-3. Next, call `cibuildwheel`. Unfortunately, MSVC has separate toolchains for compiling 32-bit and 64-bit, so you will need to run `cibuildwheel` twice: once with `CIBW_BUILD=*-win32` after setting up the `x86` build environment, and once with `CIBW_BUILD=*-win_amd64` in a `x64` environment (see previous step).
-
-
-**GitHub Action example with ilammy/msvc-dev-cmd**:
-
-```yaml
-  - uses: ilammy/msvc-dev-cmd@v1
-
-  - name: Build 64-bit wheel
-    run: python -m cibuildwheel --output-dir wheelhouse
-    env:
-      CIBW_BUILD: cp27-win_amd64
-      DISTUTILS_USE_SDK: 1
-      MSSdk: 1
-
-  - uses: ilammy/msvc-dev-cmd@v1
-    with:
-      arch: x86
-
-  - name: Build 32-bit wheel
-    run: python -m cibuildwheel --output-dir wheelhouse
-    env:
-      CIBW_BUILD: cp27-win32
-      DISTUTILS_USE_SDK: 1
-      MSSdk: 1
-```
@@ -363,3 +363,16 @@
  gh: LAMDA-NJU/Deep-Forest
  ci: [github]
  os: [apple, linux, windows]
+
+- name: cmake
+  gh: scikit-build/cmake-python-distributions
+  stars: Kitware/CMake
+  ci: [github, travisci]
+  os: [apple, linux, windows]
+  notes: Multitagged binary builds for all supported platforms, using cibw 2 config configuration.
+
+- name: ninja
+  gh: scikit-build/ninja-python-distributions
+  ci: [github, travisci]
+  os: [apple, linux, windows]
+  notes: Multitagged binary builds for all supported platforms, using cibw 2 config configuration.
@@ -1 +1 @@
-<svg xmlns="http://www.w3.org/2000/svg" role="img" viewBox="0 0 24 24" width="16px" fill="#606060"><title>Azure Pipelines icon</title><path d="M1.8 18H0v6h6v-1.8H1.8zM23 0h-8.93a2 2 0 0 0-1.67.89L9 5.99H1a1 1 0 0 0-1 1v5.5l3.5 3.61 1.2-1.29 1.5 1.5L5 17.53l1.48 1.48 1.22-1.22 1.5 1.51L8 20.5l3.5 3.5H17a1 1 0 0 0 1-1v-8l5.11-3.4A2 2 0 0 0 24 9.92V1a1 1 0 0 0-1-1zm-5 9a3 3 0 1 1 0-6 3 3 0 0 1 0 6z"/></svg>
+<svg xmlns="http://www.w3.org/2000/svg" role="img" viewBox="0 0 24 24" width="16px" fill="#606060"><title>Azure Pipelines icon</title><path d="M1.7997 22.1998h4.2001V24H.0004v-6.0002h1.7993v4.2zM12.6229 9.8975l-7.6353 7.6353 1.4792 1.4792 7.6345-7.6362-1.4784-1.4783zM4.365 15.1793l-.391-.3908c-.5042-.5042-.5828-1.3004-.1869-1.8934l4.6036-6.8958H.9979c-.5513.0014-.9975.4487-.9975 1v5.5002l3.5021 3.6036.8625-.9238zM23.9996.9999v8.9306a2 2 0 0 1-.8893 1.6632l-12.2834 8.2005a.9999.9999 0 0 1-1.2622-.1246L8.04 18.1457c.3313-.3313 6.4656-6.4672 6.7684-6.7698l-2.1855-2.1855L5.8533 15.96l-1.5258-1.525a1.0001 1.0001 0 0 1-.1246-1.2623L12.4034.8893A2 2 0 0 1 14.0666 0h8.9331c.5522 0 .9999.4477.9999.9999zm-2.9997 5.0003c0-1.6567-1.343-2.9997-2.9997-2.9997s-2.9997 1.343-2.9997 2.9997 1.343 2.9997 2.9997 2.9997 2.9997-1.343 2.9997-2.9997zM10.272 20.4625c-.4008 0-.7776-.156-1.0609-.4392l-.368-.3679-.8435.8417 3.4996 3.4996h5.5003c.5522 0 .9999-.4477.9999-.9999v-7.3899L11.1045 20.21a1.4944 1.4944 0 0 1-.8325.2525z"/></svg>
@@ -33,4 +33,4 @@ Obviously, manual steps are for chumps, so we can automate this a little by usin

 If you don't need much control over the release of a package, you can set up cibuildwheel to deliver the wheels straight to PyPI. This doesn't require anycloud storage to work - you just need to bump the version and tag it.

-[`examples/travis-ci-deploy.yml`](https://github.com/pypa/cibuildwheel/blob/master/examples/travis-ci-deploy.yml) and [`examples/github-deploy.yml`](https://github.com/pypa/cibuildwheel/blob/master/examples/github-deploy.yml) are example configurations that automatically upload wheels to PyPI. Also check out [this example repo](https://github.com/pypa/cibuildwheel-autopypi-example) for more detailed instructions on how to set this up.
+[`examples/travis-ci-deploy.yml`](https://github.com/pypa/cibuildwheel/blob/main/examples/travis-ci-deploy.yml) and [`examples/github-deploy.yml`](https://github.com/pypa/cibuildwheel/blob/main/examples/github-deploy.yml) are example configurations that automatically upload wheels to PyPI. Also check out [this example repo](https://github.com/pypa/cibuildwheel-autopypi-example) for more detailed instructions on how to set this up.
@@ -1,6 +1,10 @@

 /* Global styles */

+body {
+    overflow-wrap: break-word;
+}
+
 p {
    margin-bottom: 12px;
    line-height: 26px;
@@ -20,9 +24,9 @@ code, pre, tt {
    font-family: SFMono-Regular, Consolas, Liberation Mono, Menlo, monospace;
 }

-.hljs {
-    padding: 1em;
-    background-color: #f6f8fa;
+pre code, pre code.hljs {
+  padding: 1em;
+  background-color: #f6f8fa;
 }

 h1, h2, h3, h4, h5, h6 {
@@ -112,7 +116,21 @@ h1, h2, h3, h4, h5, h6 {
  background-color: white;
  display: flex;
  justify-content: flex-start;
-  border-bottom: 2px solid #ccc;
+  overflow-x: auto;
+  overflow-y: hidden;
+  position: relative;
+}
+.tabs-header::before {
+  position: absolute;
+  content: "";
+  bottom: 0;
+  left: 0;
+  right: 0;
+  height: 2px;
+  background: #ccc;
+}
+.tabs-header > * {
+  position: relative;
 }

 /* Style the buttons that are used to open the tab content */
@@ -126,15 +144,13 @@ h1, h2, h3, h4, h5, h6 {
  font-size: 0.9em;
  font-weight: 600;
  padding: 8px 16px;
-  border-bottom: 2px solid transparent;
-
-  /* put the border on top of the parent border */
-  margin-bottom: -2px;
+  border-bottom: 2px solid #ccc;
 }

 .tabs-header button:focus-visible {
-  /* preserve an outline for accesibility purposes */
+  /* preserve an outline for accessibility purposes */
  outline: 1px solid currentColor;
+  outline-offset: -1px;
 }

 /* Change background color of buttons on hover */
@@ -153,4 +169,53 @@ h1, h2, h3, h4, h5, h6 {
  background-color: #f1f6fa;
  padding: 1px 1em;
  padding-top: 0.8em;
+
+  /* don't collapse inner margins */
+  overflow-y: hidden;
+}
+
+/* Examples tabs styling */
+
+.tabs.examples .tabs-header {
+  justify-content: flex-end;
+  background-color: transparent;
+  border-bottom-style: none;
+  padding: 0;
+}
+.tabs.examples .tabs-header::before {
+  height: 0;
+}
+.tabs.examples .tabs-header button {
+  padding: 6px 12px;
+  border-bottom: none;
+  color: rgba(0, 0, 0, 0.3);
+  font-size: 0.8em;
+  border-top-left-radius: 4px;
+  border-top-right-radius: 4px;
+}
+.tabs-header button:hover {
+  background-color: unset;
+}
+
+.tabs.examples .tabs-header button.active {
+  border-bottom-style: none;
+  background: #f6f8fa;
+  color: inherit;
+}
+.tabs.examples .tabs-content {
+  padding: 0;
+  background-color: transparent;
+  background-color: #f6f8fa;
+}
+.tabs.examples .tabs-content .tab > * {
+  padding-left: 0.8em;
+  padding-right: 0.8em;
+}
+.tabs.examples .tabs-content .tab > pre {
+  padding-left: 0;
+  padding-right: 0;
+  margin-bottom: 0.5em;
+}
+.tabs.examples pre:first-child {
+  margin-top: 0;
 }
@@ -20,6 +20,17 @@ while (true) {
  tabContainer.insertBefore(firstTab);
  tabContainer.append(headerContainer, contentContainer)

+  // add extra classes from the first tab to the container
+  const classes = Array.from(firstTab[0].classList)
+
+  for (let i = 0; i < classes.length; i++) {
+    const element = classes[i];
+    if (element == 'tab' || element == 'admonition') {
+      continue
+    }
+    tabContainer.addClass(element)
+  }
+
  const selectTab = function (index) {
    headerContainer.children().removeClass('active')
    headerContainer.children().eq(index).addClass('active')
@@ -14,6 +14,10 @@ If your wheel didn't compile, check the list below for some debugging tips.

 - MacOS: calling cibuildwheel from a python3 script and getting a `ModuleNotFoundError`? Due to a (fixed) [bug](https://bugs.python.org/issue22490) in CPython, you'll need to [unset the `__PYVENV_LAUNCHER__` variable](https://github.com/pypa/cibuildwheel/issues/133#issuecomment-478288597) before activating a venv.

+### Building Python 2.7 / PyPy2 wheels
+
+See the [cibuildwheel version 1 docs](https://cibuildwheel.readthedocs.io/en/1.x/) for information about building Python 2.7 or PyPy2 wheels. There are lots of tricks and workaround there that are no longer required for Python 3 in cibuildwheel 2.
+
 ### Linux builds on Docker

 Linux wheels are built in the [`manylinux` docker images](https://github.com/pypa/manylinux) to provide binary compatible wheels on Linux, according to [PEP 571](https://www.python.org/dev/peps/pep-0571/). Because of this, when building with `cibuildwheel` on Linux, a few things should be taken into account:
@@ -80,7 +84,7 @@ by default, and require opt-in by setting `CIBW_ARCHS_MACOS`.
 !!! note
    Your runner needs Xcode Command Line Tools 12.2 or later to build `universal2` or `arm64`.

-    So far, only CPython 3.9 supports `universal2` and `arm64` wheels.
+    Only CPython 3.8 and newer support `universal2` and `arm64` wheels.

 Here's an example GitHub Actions workflow with a job that builds for Apple Silicon:

@@ -136,35 +140,6 @@ Here's an example GitHub Actions workflow with a job that builds for Apple Silic
 {% include "../examples/github-apple-silicon.yml" %}
 ```

-### Windows and Python 2.7
-
-Building 2.7 extensions on Windows is difficult, because the VS 2008 compiler that was used for the original Python compilation was discontinued in 2018, and has since been removed from Microsoft's downloads. Most people choose to not build Windows 2.7 wheels, or to override the compiler to something more modern.
-
-To override, you need to have a modern compiler toolchain activated, and set `DISTUTILS_USE_SDK=1` and `MSSdk=1`. For example, on GitHub Actions, you would add these steps:
-
-```yaml
-    - name: Prepare compiler environment for Windows
-      if: runner.os == 'Windows'
-      uses: ilammy/msvc-dev-cmd@v1
-      with:
-        arch: x64
-
-    - name: Set Windows environment variables
-      if: runner.os == 'Windows'
-      shell: bash
-      run: |
-        echo "DISTUTILS_USE_SDK=1" >> $GITHUB_ENV
-        echo "MSSdk=1" >> $GITHUB_ENV
-
-    # invoke cibuildwheel...
-```
-
-cibuildwheel will not try to build 2.7 on Windows unless it detects that the above two variables are set. Note that changing to a more modern compiler will mean your wheel picks up a runtime dependency to a different [Visual C++ Redistributable][]. You also need to be [a bit careful][] in designing your extension; some major binding tools like pybind11 do this for you.
-
-More on setting a custom Windows toolchain in our docs on modern C++ standards [here](cpp_standards.md#windows-and-python-27).
-
-[Visual C++ Redistributable]: https://support.microsoft.com/en-us/topic/the-latest-supported-visual-c-downloads-2647da03-1eea-4433-9aff-95f26a218cc0
-[a bit careful]: https://pybind11.readthedocs.io/en/stable/faq.html#working-with-ancient-visual-studio-2008-builds-on-windows

 ### Building packages with optional C extensions

@@ -206,7 +181,7 @@ python3 -m twine upload wheelhouse/*.whl

 ### 'ImportError: DLL load failed: The specific module could not be found' error on Windows

-Visual Studio and MSVC link the compiled binary wheels to the Microsoft Visual C++ Runtime. Normally, these are included with Python, but when compiling with a newer version of Visual Studio, it is possible users will run into problems on systems that do not have these runtime libraries installed. The solution is to ask users to download the corresponding Visual C++ Redistributable from the [Microsoft website](https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads) and install it. Since a Python installation normally includes these VC++ Redistributable files for [the version of the MSVC compiler used to compile Python](https://wiki.python.org/moin/WindowsCompilers), this is typically only a problem when compiling a Python 2.7 C extension with a newer compiler, e.g. to support a modern C++ standard (see [the section on modern C++ standards for Python 2.7](cpp_standards.md#windows-and-python-27) for more details).
+Visual Studio and MSVC link the compiled binary wheels to the Microsoft Visual C++ Runtime. Normally, these are included with Python, but when compiling with a newer version of Visual Studio, it is possible users will run into problems on systems that do not have these runtime libraries installed. The solution is to ask users to download the corresponding Visual C++ Redistributable from the [Microsoft website](https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads) and install it. Since a Python installation normally includes these VC++ Redistributable files for [the version of the MSVC compiler used to compile Python](https://wiki.python.org/moin/WindowsCompilers), this is typically only a problem when compiling a Python C extension with a newer compiler.

 Additionally, Visual Studio 2019 started linking to an even newer DLL, `VCRUNTIME140_1.dll`, besides the `VCRUNTIME140.dll` that is included with recent Python versions (starting from Python 3.5; see [here](https://wiki.python.org/moin/WindowsCompilers) for more details on the corresponding Visual Studio & MSVC versions used to compile the different Python versions). To avoid this extra dependency on `VCRUNTIME140_1.dll`, the [`/d2FH4-` flag](https://devblogs.microsoft.com/cppblog/making-cpp-exception-handling-smaller-x64/) can be added to the MSVC invocations (check out [this issue](https://github.com/pypa/cibuildwheel/issues/423) for details and references).

@@ -235,12 +210,12 @@ 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@v1.11.1.post1
+uses: pypa/cibuildwheel@v2.0.1
 ```

 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.

-Then, your `dependabot.yml` file could look like this:
+Then, your `.github/dependabot.yml` file could look like this:

 ```yaml
 version: 2
@@ -261,10 +236,10 @@ The second option, and the only one that supports other CI systems, is using a `

 ```bash
 # requirements-cibw.txt
-cibuildwheel==1.11.1.post1
+cibuildwheel==2.0.1
 ```

-Then your install step would have `python -m pip install -r requirements-cibw.txt` in it. Your `dependabot.yml` file could look like this:
+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:

 ```yaml
 version: 2
@@ -0,0 +1,13 @@
+import subprocess
+from typing import Any
+
+# Requires Python 3.7+
+
+
+def define_env(env: Any) -> None:
+    "Hook function for mkdocs-macros"
+
+    @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
@@ -46,7 +46,7 @@ To build Linux, Mac, and Windows wheels using GitHub Actions, create a `.github/
          - uses: actions/checkout@v2

          - name: Build wheels
-            run: pipx run cibuildwheel==1.11.1.post1
+            run: pipx run cibuildwheel==2.0.1

          - uses: actions/upload-artifact@v2
            with:
@@ -81,7 +81,7 @@ To build Linux, Mac, and Windows wheels using GitHub Actions, create a `.github/
          - uses: actions/setup-python@v2

          - name: Install cibuildwheel
-            run: python -m pip install cibuildwheel==1.11.1.post1
+            run: python -m pip install cibuildwheel==2.0.1

          - name: Build wheels
            run: python -m cibuildwheel --output-dir wheelhouse
@@ -96,7 +96,7 @@ Commit this file, and push to GitHub - either to your default branch, or to a PR

 For more info on this file, check out the [docs](https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions).

-[`examples/github-deploy.yml`](https://github.com/pypa/cibuildwheel/blob/master/examples/github-deploy.yml) extends this minimal example with a demonstration of how to automatically upload the built wheels to PyPI.
+[`examples/github-deploy.yml`](https://github.com/pypa/cibuildwheel/blob/main/examples/github-deploy.yml) extends this minimal example with a demonstration of how to automatically upload the built wheels to PyPI.


 # Azure Pipelines [linux/mac/windows] {: #azure-pipelines}
@@ -109,16 +109,13 @@ To build Linux, Mac, and Windows wheels on Azure Pipelines, create a `azure-pipe
 {% include "../examples/azure-pipelines-minimal.yml" %}
 ```

-!!! note
-    To support Python 3.5 on Windows, make sure to specify the use of `{vmImage: 'vs2017-win2016'}` on Windows, to ensure the required toolchain is available.
-
 Commit this file, enable building of your repo on Azure Pipelines, and push.

 Wheels will be stored for you and available through the Pipelines interface. For more info on this file, check out the [docs](https://docs.microsoft.com/en-us/azure/devops/pipelines/yaml-schema).

-# Travis CI [linux/mac/windows] {: #travis-ci}
+# Travis CI [linux/windows] {: #travis-ci}

-To build Linux, Mac, and Windows wheels on Travis CI, create a `.travis.yml` file in your repo.
+To build Linux and Windows wheels on Travis CI, create a `.travis.yml` file in your repo.

 > .travis.yml

@@ -126,13 +123,11 @@ To build Linux, Mac, and Windows wheels on Travis CI, create a `.travis.yml` fil
 {% include "../examples/travis-ci-minimal.yml" %}
 ```

-Note that building Windows Python 2.7 wheels on Travis is unsupported unless using a newer compiler [via a workaround](cpp_standards.md).
-
 Commit this file, enable building of your repo on Travis CI, and push.

 Then setup a deployment method by following the [Travis CI deployment docs](https://docs.travis-ci.com/user/deployment/), or see [Delivering to PyPI](deliver-to-pypi.md). For more info on `.travis.yml`, check out the [docs](https://docs.travis-ci.com/).

-[`examples/travis-ci-deploy.yml`](https://github.com/pypa/cibuildwheel/blob/master/examples/travis-ci-deploy.yml) extends this minimal example with a demonstration of how to automatically upload the built wheels to PyPI.
+[`examples/travis-ci-deploy.yml`](https://github.com/pypa/cibuildwheel/blob/main/examples/travis-ci-deploy.yml) extends this minimal example with a demonstration of how to automatically upload the built wheels to PyPI.

 # AppVeyor [linux/mac/windows] {: #appveyor}

@@ -12,7 +12,7 @@ stack: python 3.7
 init:
 - cmd: set PATH=C:\Python37;C:\Python37\Scripts;%PATH%

-install: python -m pip install cibuildwheel==1.11.1.post1
+install: python -m pip install cibuildwheel==2.0.1

 build_script: python -m cibuildwheel --output-dir wheelhouse

@@ -6,7 +6,7 @@ jobs:
    - bash: |
        set -o errexit
        python3 -m pip install --upgrade pip
-        pip3 install cibuildwheel==1.11.1.post1
+        pip3 install cibuildwheel==2.0.1
      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==1.11.1.post1
+        python3 -m pip install cibuildwheel==2.0.1
      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==1.11.1.post1
+        pip install cibuildwheel==2.0.1
      displayName: Install dependencies
    - bash: cibuildwheel --output-dir wheelhouse .
      displayName: Build wheels
@@ -11,7 +11,7 @@ jobs:
      - run:
          name: Build the Linux wheels.
          command: |
-            pip3 install --user cibuildwheel==1.11.1.post1
+            pip3 install --user cibuildwheel==2.0.1
            cibuildwheel --output-dir wheelhouse
      - store_artifacts:
          path: wheelhouse/
@@ -19,13 +19,13 @@ jobs:
  osx-wheels:
    working_directory: ~/osx-wheels
    macos:
-      xcode: 10.0.0
+      xcode: 12.5.1
    steps:
      - checkout
      - run:
          name: Build the OS X wheels.
          command: |
-            pip3 install cibuildwheel==1.11.1.post1
+            pip3 install cibuildwheel==2.0.1
            cibuildwheel --output-dir wheelhouse
      - store_artifacts:
          path: wheelhouse/
@@ -10,7 +10,7 @@ jobs:
      - uses: actions/checkout@v2

      - name: Build wheels
-        uses: pypa/cibuildwheel@v1.11.1.post1
+        uses: pypa/cibuildwheel@v2.0.1
        env:
          CIBW_ARCHS_MACOS: x86_64 universal2

@@ -27,7 +27,7 @@ jobs:
          python-version: '3.8'

      - name: Build wheels
-        uses: pypa/cibuildwheel@v1.11.1.post1
+        uses: pypa/cibuildwheel@v2.0.1

      - uses: actions/upload-artifact@v2
        with:
@@ -64,7 +64,7 @@ jobs:
          name: artifact
          path: dist

-      - uses: pypa/gh-action-pypi-publish@master
+      - uses: pypa/gh-action-pypi-publish@v1.4.2
        with:
          user: __token__
          password: ${{ secrets.pypi_password }}
@@ -14,7 +14,7 @@ jobs:
      - uses: actions/checkout@v2

      - name: Build wheels
-        uses: pypa/cibuildwheel@v1.11.1.post1
+        uses: pypa/cibuildwheel@v2.0.1
        # to supply options, put them in 'env', like:
        # env:
        #   CIBW_SOME_OPTION: value
@@ -25,7 +25,7 @@ jobs:
          platforms: all

      - name: Build wheels
-        uses: pypa/cibuildwheel@v1.11.1.post1
+        uses: pypa/cibuildwheel@v2.0.1
        env:
          # configure cibuildwheel to build native archs ('auto'), and some
          # emulated ones
@@ -12,7 +12,7 @@ linux:
    DOCKER_TLS_CERTDIR: ""
  script:
    - curl -sSL https://get.docker.com/ | sh
-    - python -m pip install cibuildwheel==1.11.1.post1
+    - python -m pip install cibuildwheel==2.0.1
    - cibuildwheel --output-dir wheelhouse
  artifacts:
    paths:
@@ -9,9 +9,6 @@ jobs:
  include:
    # perform a linux build
    - services: docker
-    # and a mac build
-    - os: osx
-      language: shell
    # and a windows build
    - os: windows
      language: shell
@@ -22,7 +19,7 @@ jobs:
        - ln -s /c/Python38/python.exe /c/Python38/python3.exe

 install:
-  - python3 -m pip install cibuildwheel==1.11.1.post1
+  - python3 -m pip install cibuildwheel==2.0.1

 script:
  # build the wheels, put them into './wheelhouse'
@@ -15,9 +15,6 @@ jobs:
    # perform a linux S390X build
    - services: docker
      arch: s390x
-    # and a mac build
-    - os: osx
-      language: shell
    # and a windows build
    - os: windows
      language: shell
@@ -28,7 +25,7 @@ jobs:
        - ln -s /c/Python38/python.exe /c/Python38/python3.exe

 install:
-  - python3 -m pip install cibuildwheel==1.11.1.post1
+  - python3 -m pip install cibuildwheel==2.0.1

 script:
  # build the wheels, put them into './wheelhouse'
@@ -1,7 +1,7 @@
 # In this configuration, the package is tested against multiple versions of python
 # on Linux and on one version of Python on Windows. If and only if all tests pass
 # will the wheels be built and deployed. Further, deployment is only initiated if
-# the current branch is "master", the current commit is tagged, and the current
+# the current branch is "main", the current commit is tagged, and the current
 # repo is yours (e.g. it won't run on a Pull Request). For convenience, a source
 # distribution is also created.

@@ -57,17 +57,7 @@ jobs:
    - stage: deploy
      name: Build and deploy Linux wheels
      services: docker
-      install: python3 -m pip install cibuildwheel==1.11.1.post1
-      script: python3 -m cibuildwheel --output-dir wheelhouse
-      after_success: |
-        python3 -m pip install twine
-        python3 -m twine upload --skip-existing wheelhouse/*.whl
-    # Deploy on mac
-    - stage: deploy
-      name: Build and deploy macOS wheels
-      os: osx
-      language: shell
-      install: python3 -m pip install cibuildwheel==1.11.1.post1
+      install: python3 -m pip install cibuildwheel==2.0.1
      script: python3 -m cibuildwheel --output-dir wheelhouse
      after_success: |
        python3 -m pip install twine
@@ -77,7 +67,7 @@ jobs:
      name: Build and deploy Windows wheels
      os: windows
      language: shell
-      install: python3 -m pip install cibuildwheel==1.11.1.post1
+      install: python3 -m pip install cibuildwheel==2.0.1
      script: python3 -m cibuildwheel --output-dir wheelhouse
      after_success: |
        python3 -m pip install twine
@@ -41,3 +41,7 @@ markdown_extensions:
 plugins:
  - include-markdown
  - search
+  - macros:
+      module_name: docs/main
+      j2_variable_start_string: «
+      j2_variable_end_string: »
@@ -0,0 +1,102 @@
+import shutil
+import sys
+from pathlib import Path
+
+import nox
+
+nox.options.sessions = ["lint", "tests"]
+
+PYTHON_ALL_VERSIONS = ["3.6", "3.7", "3.8", "3.9"]
+
+DIR = Path(__file__).parent.resolve()
+
+
+@nox.session
+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:
+        session.run("pytest", "unit_test", *unit_test_args)
+        session.run("pytest", "test", "-x", "--durations", "0", "--timeout=2400", "test")
+
+
+@nox.session
+def lint(session: nox.Session) -> None:
+    """
+    Run the linter.
+    """
+    session.install("pre-commit")
+    session.run("pre-commit", "run", "--all-files", *session.posargs)
+
+
+@nox.session(python=PYTHON_ALL_VERSIONS)
+def update_constraints(session: nox.Session) -> None:
+    """
+    Update the dependencies inplace.
+    """
+    session.install("requests", "pip-tools")
+    session.run("python", "bin/update_dependencies.py")
+
+
+@nox.session
+def update_pins(session: nox.Session) -> None:
+    """
+    Update the python and docker pins version inplace.
+    """
+    session.install("-e", ".[bin]")
+    session.run("python", "bin/update_pythons.py", "--force")
+    session.run("python", "bin/update_docker.py")
+
+
+@nox.session
+def update_proj(session: nox.Session) -> None:
+    """
+    Update the README inplace.
+    """
+    session.install("-e", ".[bin]")
+    session.run(
+        "python",
+        "bin/projects.py",
+        "docs/data/projects.yml",
+        "--readme=README.md",
+        *session.posargs,
+    )
+
+
+@nox.session
+def docs(session: nox.Session) -> None:
+    """
+    Build the docs.
+    """
+    session.install("-e", ".[docs]")
+
+    if session.posargs:
+        if "serve" in session.posargs:
+            session.run("mkdocs", "serve")
+        else:
+            session.error("Unrecognized args, use 'serve'")
+    else:
+        session.run("mkdocs", "build")
+
+
+@nox.session
+def build(session: nox.Session) -> None:
+    """
+    Build an SDist and wheel.
+    """
+
+    build_p = DIR.joinpath("build")
+    if build_p.exists():
+        shutil.rmtree(build_p)
+
+    dist_p = DIR.joinpath("dist")
+    if dist_p.exists():
+        shutil.rmtree(dist_p)
+
+    session.install("build")
+    session.run("python", "-m", "build")
@@ -6,6 +6,62 @@ requires = [

 build-backend = "setuptools.build_meta"

+
 [tool.black]
 line-length = 100
 target-version = ['py36', 'py37', 'py38', 'py39']
+
+
+[tool.isort]
+profile = "black"
+multi_line_output = 3
+
+
+[tool.pytest.ini_options]
+minversion = 6.0
+junit_family = "xunit2"
+testpaths = [
+    "test",
+    "unit_test",
+]
+
+
+[tool.mypy]
+python_version = 3.7
+files = [
+    "cibuildwheel/*.py",
+    "test/**/*.py",
+    "unit_test/**/*.py",
+    "bin/*.py"
+]
+warn_unused_configs = true
+warn_redundant_casts = true
+no_implicit_reexport = true
+strict_equality = true
+warn_unused_ignores = true
+check_untyped_defs = true
+
+disallow_subclassing_any = true
+disallow_any_generics = true
+warn_return_any = true
+no_implicit_optional = true
+
+[[tool.mypy.overrides]]
+module = "cibuildwheel.*"
+disallow_untyped_defs = true
+disallow_untyped_calls = true
+disallow_incomplete_defs = true
+disallow_untyped_decorators = true
+
+[[tool.mypy.overrides]]
+module = [
+    "setuptools",
+    "pytest", # ignored in pre-commit to speed up check
+    "bashlex",
+    "toml.encoder", # encoder missing from stub package
+    "bracex",
+    "importlib_resources",
+    "nox",
+    "github",
+]
+ignore_missing_imports = true
@@ -1,6 +1,6 @@
 [metadata]
 name = cibuildwheel
-version = 1.11.1.post1
+version = 2.0.1
 description = Build Python wheels on CI with minimal configuration.
 long_description = file: README.md
 long_description_content_type = text/markdown
@@ -65,57 +65,3 @@ exclude =
    env??/,
    .venv/,
    site/
-
-[tool:pytest]
-junit_family = xunit2
-testpaths =
-    test
-    unit_test
-
-[mypy]
-python_version = 3.7
-files = cibuildwheel/*.py,test/**/*.py,unit_test/**/*.py,bin/*.py
-warn_unused_configs = True
-warn_redundant_casts = True
-
-[mypy-test.*,mypy-unit_test.*]
-check_untyped_defs = True
-
-[mypy-cibuildwheel.*]
-disallow_any_generics = True
-disallow_subclassing_any = True
-disallow_untyped_calls = True
-disallow_untyped_defs = True
-disallow_incomplete_defs = True
-check_untyped_defs = True
-disallow_untyped_decorators = True
-no_implicit_optional = True
-warn_unused_ignores = True
-warn_return_any = True
-no_implicit_reexport = True
-strict_equality = True
-
-[mypy-setuptools.*]
-ignore_missing_imports = True
-
-# Ignored for pre-commit to speed up check
-# Not ignored if manually running and pytest installed
-[mypy-pytest.*]
-ignore_missing_imports = True
-
-[mypy-bashlex.*]
-ignore_missing_imports = True
-
-# Has type stubs, but no pyproject.toml or .pyi files in the wheel.
-[mypy-toml.*]
-ignore_missing_imports = True
-
-[mypy-bracex.*]
-ignore_missing_imports = True
-
-[mypy-importlib_resources.*]
-ignore_missing_imports = True
-
-[tool:isort]
-profile = black
-multi_line_output = 3
@@ -5,27 +5,42 @@ extras = {
        "mkdocs-include-markdown-plugin==2.8.0",
        "mkdocs==1.0.4",
        "pymdown-extensions",
+        "mkdocs-macros-plugin",
    ],
    "test": [
        "jinja2",
-        "pytest>=4",
+        "pytest>=6",
        "pytest-timeout",
    ],
-    "dev": [
+    "bin": [
        "click",
        "ghapi",
-        "mypy>=0.800",
-        "packaging>=20.8",
        "pip-tools",
        "pygithub",
        "pyyaml",
        "requests",
        "rich>=9.6",
-        "typing-extensions",
+        "packaging>=21.0",
+    ],
+    "mypy": [
+        "mypy>=0.901",
+        "types-jinja2",
+        "types-certifi",
+        "types-toml",
+        "types-jinja2",
+        "types-pyyaml",
+        "types-click",
+        "types-requests",
+        "types-toml",
    ],
 }

+extras["dev"] = [
+    *extras["mypy"],
+    *extras["test"],
+    *extras["bin"],
+]
+
 extras["all"] = sum(extras.values(), [])
-extras["dev"] += extras["test"]

 setup(extras_require=extras)
@@ -1,7 +1,9 @@
+from typing import Dict
+
 import pytest


-def pytest_addoption(parser):
+def pytest_addoption(parser) -> None:
    parser.addoption(
        "--run-emulation", action="store_true", default=False, help="run emulation tests"
    )
@@ -11,7 +13,7 @@ def pytest_configure(config):
    config.addinivalue_line("markers", "emulation: mark test requiring qemu binfmt_misc to run")


-def pytest_collection_modifyitems(config, items):
+def pytest_collection_modifyitems(config, items) -> None:
    if config.getoption("--run-emulation"):
        # --run-emulation given in cli: do not skip emulation tests
        return
@@ -19,3 +21,10 @@ def pytest_collection_modifyitems(config, items):
    for item in items:
        if "emulation" in item.keywords:
            item.add_marker(skip_emulation)
+
+
+@pytest.fixture(
+    params=[{"CIBW_BUILD_FRONTEND": "pip"}, {"CIBW_BUILD_FRONTEND": "build"}], ids=["pip", "build"]
+)
+def build_frontend_env(request) -> Dict[str, str]:
+    return request.param  # type: ignore
@@ -1,4 +1,3 @@
-import platform
 import textwrap

 import pytest
@@ -19,12 +18,12 @@ basic_project = test_projects.new_c_project(
 )


-def test(tmp_path):
+def test(tmp_path, build_frontend_env):
    project_dir = tmp_path / "project"
    basic_project.generate(project_dir)

    # build the wheels
-    actual_wheels = utils.cibuildwheel_run(project_dir)
+    actual_wheels = utils.cibuildwheel_run(project_dir, add_env=build_frontend_env)

    # check that the expected wheels are produced
    expected_wheels = utils.expected_wheels("spam", "0.1.0")
@@ -53,16 +52,8 @@ def test_build_identifiers(tmp_path):

    # check that the number of expected wheels matches the number of build
    # identifiers
-    # after adding CIBW_MANYLINUX_IMAGE to support manylinux2010, there
-    # can be multiple wheels for each wheel, though, so we need to limit
-    # the expected wheels
-    if platform.machine() in ["x86_64", "i686"]:
-        expected_wheels = [
-            w
-            for w in utils.expected_wheels("spam", "0.1.0")
-            if "-manylinux" not in w or "-manylinux1" in w
-        ]
-    else:
-        expected_wheels = utils.expected_wheels("spam", "0.1.0")
-    build_identifiers = utils.cibuildwheel_get_build_identifiers(project_dir)
+    expected_wheels = utils.expected_wheels("spam", "0.1.0")
+    build_identifiers = utils.cibuildwheel_get_build_identifiers(
+        project_dir, prerelease_pythons=True
+    )
    assert len(expected_wheels) == len(build_identifiers)
@@ -25,8 +25,13 @@ project_with_before_build_asserts = test_projects.new_c_project(
            stored_executable = f.read()
        print('stored_executable', stored_executable)
        print('sys.executable', sys.executable)
+
        # windows/mac are case insensitive
-        assert os.path.realpath(stored_executable).lower() == os.path.realpath(sys.executable).lower()
+        stored_path = os.path.realpath(stored_executable).lower()
+        current_path = os.path.realpath(sys.executable).lower()
+
+        # TODO: This is not valid in an virtual environment
+        assert stored_path == current_path, '{0} != {1}'.format(stored_path, current_path)
        """
    )
 )
@@ -49,11 +49,11 @@ def test(tmp_path):
            # checked in setup.py
            "CIBW_BEFORE_TEST": """python -c "import sys; open('/tmp/pythonversion.txt', 'w').write(sys.version)" && python -c "import sys; open('/tmp/pythonprefix.txt', 'w').write(sys.prefix)" && python -m pip install {project}/dependency""",
            "CIBW_BEFORE_TEST_WINDOWS": """python -c "import sys; open('c:\\pythonversion.txt', 'w').write(sys.version)" && python -c "import sys; open('c:\\pythonprefix.txt', 'w').write(sys.prefix)" && python -m pip install {project}/dependency""",
-            "CIBW_TEST_REQUIRES": "nose",
+            "CIBW_TEST_REQUIRES": "pytest",
            # the 'false ||' bit is to ensure this command runs in a shell on
            # mac/linux.
-            "CIBW_TEST_COMMAND": "false || nosetests {project}/test",
-            "CIBW_TEST_COMMAND_WINDOWS": "nosetests {project}/test",
+            "CIBW_TEST_COMMAND": "false || pytest {project}/test",
+            "CIBW_TEST_COMMAND_WINDOWS": "pytest {project}/test",
        },
    )

@@ -5,11 +5,11 @@ from . import test_projects, utils
 project_with_skip_asserts = test_projects.new_c_project(
    setup_py_add=textwrap.dedent(
        r"""
-        # explode if run on Python 2.7 or Python 3.7 (these should be skipped)
-        if sys.version_info[0:2] == (2, 7):
-            raise Exception("Python 2.7 should not be built")
+        # explode if run on PyPyor Python 3.7 (these should be skipped)
+        if sys.implementation.name != "cpython":
+            raise Exception("Only CPython shall be built")
        if sys.version_info[0:2] == (3, 7):
-            raise Exception("Python 3.7 should be skipped")
+            raise Exception("CPython 3.7 should be skipped")
        """
    )
 )
@@ -23,12 +23,12 @@ def test(tmp_path):
    actual_wheels = utils.cibuildwheel_run(
        project_dir,
        add_env={
-            "CIBW_BUILD": "cp3?-*",
+            "CIBW_BUILD": "cp3*-*",
            "CIBW_SKIP": "cp37-*",
        },
    )

-    # check that we got the right wheels. There should be no 2.7 or 3.7.
+    # check that we got the right wheels. There should be no PyPy or 3.7.
    expected_wheels = [
        w for w in utils.expected_wheels("spam", "0.1.0") if ("-cp3" in w) and ("-cp37" not in w)
    ]
@@ -36,38 +36,18 @@ spam_system(PyObject *self, PyObject *args)
 }

 /* Module initialization */
-
-#if PY_MAJOR_VERSION >= 3
-    #define MOD_INIT(name) PyMODINIT_FUNC PyInit_##name(void)
-    #define MOD_DEF(m, name, doc, methods, module_state_size) \
-        static struct PyModuleDef moduledef = { \
-            PyModuleDef_HEAD_INIT, name, doc, module_state_size, methods, }; \
-        m = PyModule_Create(&moduledef);
-    #define MOD_RETURN(m) return m;
-#else
-    #define MOD_INIT(name) PyMODINIT_FUNC init##name(void)
-    #define MOD_DEF(m, name, doc, methods, module_state_size) \
-        m = Py_InitModule3(name, methods, doc);
-    #define MOD_RETURN(m) return;
-#endif
-
 static PyMethodDef module_methods[] = {
    {"system", (PyCFunction)spam_system, METH_VARARGS,
     "Execute a shell command."},
    {NULL}  /* Sentinel */
 };

-MOD_INIT(spam)
+PyMODINIT_FUNC PyInit_spam(void)
 {
-    PyObject* m;
-
-    MOD_DEF(m,
-            "spam",
-            "Example module",
-            module_methods,
-            -1)
-
-    MOD_RETURN(m)
+    static struct PyModuleDef moduledef = {
+        PyModuleDef_HEAD_INIT, "spam", "Example module", -1, module_methods,
+    };
+    return PyModule_Create(&moduledef);
 }
 """

@@ -87,15 +67,8 @@ def test_cpp11(tmp_path):

    cpp11_project.generate(project_dir)

-    # VC++ for Python 2.7 does not support modern standards
-    add_env = {"CIBW_SKIP": "cp27-win* pp27-win32"}
-
-    actual_wheels = utils.cibuildwheel_run(project_dir, add_env=add_env)
-    expected_wheels = [
-        w
-        for w in utils.expected_wheels("spam", "0.1.0")
-        if "cp27-cp27m-win" not in w and "pp27-pypy_73-win32" not in w
-    ]
+    actual_wheels = utils.cibuildwheel_run(project_dir)
+    expected_wheels = [w for w in utils.expected_wheels("spam", "0.1.0")]

    assert set(actual_wheels) == set(expected_wheels)

@@ -113,27 +86,17 @@ def test_cpp14(tmp_path):

    cpp14_project.generate(project_dir)

-    # VC++ for Python 2.7 does not support modern standards
-    # The manylinux1 docker image does not have a compiler which supports C++11
-    add_env = {"CIBW_SKIP": "cp27-win* pp27-win32"}
-
-    actual_wheels = utils.cibuildwheel_run(project_dir, add_env=add_env)
-    expected_wheels = [
-        w
-        for w in utils.expected_wheels("spam", "0.1.0")
-        if "cp27-cp27m-win" not in w and "pp27-pypy_73-win32" not in w
-    ]
+    actual_wheels = utils.cibuildwheel_run(project_dir)
+    expected_wheels = [w for w in utils.expected_wheels("spam", "0.1.0")]

    assert set(actual_wheels) == set(expected_wheels)


 cpp17_project = cpp_test_project.copy()

-# Python and PyPy 2.7 headers use the `register` keyword, which is forbidden in
-# the C++17 standard, so we need the -Wno-register or /wd5033 options
-cpp17_project.template_context["extra_compile_args"] = (
-    ["/std:c++17", "/wd5033"] if utils.platform == "windows" else ["-std=c++17", "-Wno-register"]
-)
+cpp17_project.template_context["extra_compile_args"] = [
+    "/std:c++17" if utils.platform == "windows" else "-std=c++17"
+]
 cpp17_project.template_context[
    "spam_cpp_top_level_add"
 ] = r"""
@@ -153,7 +116,7 @@ def test_cpp17(tmp_path):

    # Pypy's distutils sets the default compiler to 'msvc9compiler', which
    # is too old to support cpp17.
-    add_env = {"CIBW_SKIP": "cp27-win* pp??-*"}
+    add_env = {"CIBW_SKIP": "pp??-*"}

    if utils.platform == "macos":
        add_env["MACOSX_DEPLOYMENT_TARGET"] = "10.13"
@@ -162,61 +125,7 @@ def test_cpp17(tmp_path):
    expected_wheels = [
        w
        for w in utils.expected_wheels("spam", "0.1.0", macosx_deployment_target="10.13")
-        if "cp27-cp27m-win" not in w and "-pp" not in w
-    ]
-
-    assert set(actual_wheels) == set(expected_wheels)
-
-
-def test_cpp17_py27_modern_msvc_workaround(tmp_path):
-    # This test checks the workaround for building Python 2.7 wheel with MSVC 14
-
-    if utils.platform != "windows":
-        pytest.skip("the test is only relevant to the Windows build")
-
-    if os.environ.get("APPVEYOR_BUILD_WORKER_IMAGE", "") == "Visual Studio 2015":
-        pytest.skip("Visual Studio 2015 does not support C++17")
-
-    project_dir = tmp_path / "project"
-    cpp17_project.generate(project_dir)
-
-    # VC++ for Python 2.7 (i.e., MSVC 9) does not support modern standards
-    # This is a workaround which forces distutils/setupstools to a newer version
-    # Wheels compiled need a more modern C++ redistributable installed, which is not
-    # included with Python: see documentation for more info
-    # DISTUTILS_USE_SDK and MSSdk=1 tell distutils/setuptools that we are adding
-    # MSVC's compiler, tools, and libraries to PATH ourselves
-    add_env = {"DISTUTILS_USE_SDK": "1", "MSSdk": "1"}
-
-    # Use existing setuptools code to run Visual Studio's vcvarsall.bat and get the
-    # necessary environment variables, since running vcvarsall.bat in a subprocess
-    # does not keep the relevant environment variables
-    # There are different environment variables for 32-bit/64-bit targets, so we
-    # need to run cibuildwheel twice, once for 32-bit with `vcvarsall.bat x86, and
-    # once for 64-bit with `vcvarsall.bat x64`
-    # In a normal CI setup, just run vcvarsall.bat before running cibuildwheel and set
-    # DISTUTILS_USE_SDK and MSSdk
-    import setuptools
-
-    def add_vcvars(prev_env, platform):
-        vcvarsall_env = setuptools.msvc.msvc14_get_vc_env(platform)
-        env = prev_env.copy()
-        for vcvar in ["path", "include", "lib"]:
-            env[vcvar] = vcvarsall_env[vcvar]
-        return env
-
-    add_env_x86 = add_vcvars(add_env, "x86")
-    add_env_x86["CIBW_BUILD"] = "?p27-win32"
-    actual_wheels = utils.cibuildwheel_run(project_dir, add_env=add_env_x86)
-
-    add_env_x64 = add_vcvars(add_env, "x64")
-    add_env_x64["CIBW_BUILD"] = "cp27-win_amd64"
-    actual_wheels += utils.cibuildwheel_run(project_dir, add_env=add_env_x64)
-
-    expected_wheels = [
-        w
-        for w in utils.expected_wheels("spam", "0.1.0", exclude_27=False)
-        if "cp27-cp27m-win" in w or "pp27-pypy_73-win32" in w
+        if "-pp" not in w
    ]

    assert set(actual_wheels) == set(expected_wheels)
@@ -47,39 +47,28 @@ def get_versions_from_constraint_file(constraint_file):
    }


-@pytest.mark.parametrize("python_version", ["2.7", "3.5", "3.6", "3.8"])
-def test_pinned_versions(tmp_path, python_version):
+@pytest.mark.parametrize("python_version", ["3.6", "3.8", "3.9"])
+def test_pinned_versions(tmp_path, python_version, build_frontend_env):
    if utils.platform == "linux":
        pytest.skip("linux doesn't pin individual tool versions, it pins manylinux images instead")

-    if utils.platform == "windows" and python_version == "2.7":
-        pytest.skip("Windows requires a workaround")
-
-    is_macos_11_or_later = utils.platform == "macos" and utils.get_macos_version() >= (10, 16)
-
-    if is_macos_11_or_later and python_version == "3.5":
-        pytest.skip("CPython 3.5 doesn't work on macOS Big Sur+")
-
    project_dir = tmp_path / "project"
    project_with_expected_version_checks.generate(project_dir)

    build_environment = {}

-    if python_version == "2.7":
-        constraint_filename = "constraints-python27.txt"
-        build_pattern = "[cp]p27-*"
-    elif python_version == "3.5":
-        constraint_filename = "constraints-python35.txt"
-        build_pattern = "[cp]p35-*"
-    elif python_version == "3.6":
+    if python_version == "3.6":
        constraint_filename = "constraints-python36.txt"
        build_pattern = "[cp]p36-*"
    elif python_version == "3.7":
        constraint_filename = "constraints-python37.txt"
        build_pattern = "[cp]p37-*"
+    elif python_version == "3.8":
+        constraint_filename = "constraints-python38.txt"
+        build_pattern = "[cp]p38-*"
    else:
        constraint_filename = "constraints.txt"
-        build_pattern = "[cp]p38-*"
+        build_pattern = "[cp]p39-*"

    constraint_file = cibuildwheel.util.resources_dir / constraint_filename
    constraint_versions = get_versions_from_constraint_file(constraint_file)
@@ -96,19 +85,12 @@ def test_pinned_versions(tmp_path, python_version):
        add_env={
            "CIBW_BUILD": build_pattern,
            "CIBW_ENVIRONMENT": cibw_environment_option,
+            **build_frontend_env,
        },
    )

    # also check that we got the right wheels
-    if python_version == "2.7":
-        expected_wheels = [
-            w for w in utils.expected_wheels("spam", "0.1.0") if "-cp27" in w or "-pp27" in w
-        ]
-    elif python_version == "3.5":
-        expected_wheels = [
-            w for w in utils.expected_wheels("spam", "0.1.0") if "-cp35" in w or "-pp35" in w
-        ]
-    elif python_version == "3.6":
+    if python_version == "3.6":
        expected_wheels = [
            w for w in utils.expected_wheels("spam", "0.1.0") if "-cp36" in w or "-pp36" in w
        ]
@@ -116,31 +98,31 @@ def test_pinned_versions(tmp_path, python_version):
        expected_wheels = [
            w for w in utils.expected_wheels("spam", "0.1.0") if "-cp38" in w or "-pp38" in w
        ]
+    elif python_version == "3.9":
+        expected_wheels = [
+            w for w in utils.expected_wheels("spam", "0.1.0") if "-cp39" in w or "-pp39" in w
+        ]
    else:
        raise ValueError("unhandled python version")

    assert set(actual_wheels) == set(expected_wheels)


-@pytest.mark.parametrize("python_version", ["2.7", "3.x"])
-def test_dependency_constraints_file(tmp_path, python_version):
+def test_dependency_constraints_file(tmp_path, build_frontend_env):
    if utils.platform == "linux":
        pytest.skip("linux doesn't pin individual tool versions, it pins manylinux images instead")

-    if utils.platform == "windows" and python_version == "2.7":
-        pytest.skip("Windows + Travis CI requires a workaround")
-
    project_dir = tmp_path / "project"
    project_with_expected_version_checks.generate(project_dir)

    tool_versions = {
        "pip": "20.0.2",
-        "setuptools": "44.0.0" if python_version == "2.7" else "46.0.0",
+        "setuptools": "53.0.0",
        "wheel": "0.34.2",
-        "virtualenv": "20.0.10",
+        "virtualenv": "20.0.35",
    }

-    constraints_file = tmp_path / "constraints.txt"
+    constraints_file = tmp_path / "constraints file.txt"
    constraints_file.write_text(
        textwrap.dedent(
            """
@@ -148,6 +130,7 @@ def test_dependency_constraints_file(tmp_path, python_version):
            setuptools=={setuptools}
            wheel=={wheel}
            virtualenv=={virtualenv}
+            importlib-metadata<3,>=0.12; python_version < "3.8"
            """.format(
                **tool_versions
            )
@@ -166,22 +149,13 @@ def test_dependency_constraints_file(tmp_path, python_version):
    actual_wheels = utils.cibuildwheel_run(
        project_dir,
        add_env={
-            "CIBW_BUILD": "[cp]p27-*" if python_version == "2.7" else "[cp]p3?-*",
            "CIBW_ENVIRONMENT": cibw_environment_option,
            "CIBW_DEPENDENCY_VERSIONS": str(constraints_file),
+            **build_frontend_env,
        },
    )

    # also check that we got the right wheels
-    if python_version == "2.7":
-        expected_wheels = [
-            w for w in utils.expected_wheels("spam", "0.1.0") if "-cp27" in w or "-pp27" in w
-        ]
-    else:
-        expected_wheels = [
-            w
-            for w in utils.expected_wheels("spam", "0.1.0")
-            if "-cp27" not in w and "-pp27" not in w
-        ]
+    expected_wheels = utils.expected_wheels("spam", "0.1.0")

    assert set(actual_wheels) == set(expected_wheels)
@@ -37,7 +37,7 @@ def test(tmp_path):
        add_env={
            "CIBW_MANYLINUX_X86_64_IMAGE": "dockcross/manylinux2010-x64",
            "CIBW_MANYLINUX_I686_IMAGE": "dockcross/manylinux2010-x86",
-            "CIBW_SKIP": "pp* cp27-* cp39-*",
+            "CIBW_BUILD": "cp3{6,7,8,9}-*",
        },
    )

@@ -45,6 +45,6 @@ def test(tmp_path):
    expected_wheels = [
        w
        for w in utils.expected_wheels("spam", "0.1.0")
-        if "-pp" not in w and "-cp39-" not in w and "-cp27-" not in w
+        if "-cp36-" in w or "-cp37-" in w or "-cp38-" in w or "-cp39-" in w
    ]
    assert set(actual_wheels) == set(expected_wheels)
@@ -64,21 +64,24 @@ def test(manylinux_image, tmp_path):
        "CIBW_MANYLINUX_AARCH64_IMAGE": manylinux_image,
        "CIBW_MANYLINUX_PPC64LE_IMAGE": manylinux_image,
        "CIBW_MANYLINUX_S390X_IMAGE": manylinux_image,
+        "CIBW_MANYLINUX_PYPY_AARCH64_IMAGE": manylinux_image,
+        "CIBW_MANYLINUX_PYPY_I686_IMAGE": manylinux_image,
    }
-    if manylinux_image == "manylinux1":
-        # We don't have a manylinux1 image for PyPy
-        add_env["CIBW_SKIP"] = "pp*"
-    elif manylinux_image in {"manylinux2014", "manylinux_2_24"}:
-        # We don't have a manylinux2014 / 'manylinux_2_24' image for PyPy (yet?)
-        # Python 2.7 not available on manylinux2014 / 'manylinux_2_24'
-        add_env["CIBW_SKIP"] = "cp27* pp*"
+    if manylinux_image in {"manylinux1"}:
+        # We don't have a manylinux1 image for PyPy & CPython 3.10 and above
+        add_env["CIBW_SKIP"] = "pp* cp31*"
+
    actual_wheels = utils.cibuildwheel_run(project_dir, add_env=add_env)

-    expected_wheels = [
-        w for w in utils.expected_wheels("spam", "0.1.0", manylinux_versions=[manylinux_image])
-    ]
-    if manylinux_image in {"manylinux2014", "manylinux_2_24"}:
-        expected_wheels = [w for w in expected_wheels if "-cp27" not in w]
-    if manylinux_image in {"manylinux1", "manylinux2014", "manylinux_2_24"}:
-        expected_wheels = [w for w in expected_wheels if "-pp" not in w]
+    platform_tag_map = {
+        "manylinux1": ["manylinux_2_5", "manylinux1"],
+        "manylinux2010": ["manylinux_2_12", "manylinux2010"],
+        "manylinux2014": ["manylinux_2_17", "manylinux2014"],
+    }
+    expected_wheels = utils.expected_wheels(
+        "spam", "0.1.0", manylinux_versions=platform_tag_map.get(manylinux_image, [manylinux_image])
+    )
+    if manylinux_image in {"manylinux1"}:
+        # remove PyPy & CPython 3.10 and above
+        expected_wheels = [w for w in expected_wheels if "-pp" not in w and "-cp31" not in w]
    assert set(actual_wheels) == set(expected_wheels)
@@ -1,4 +1,3 @@
-import os
 import textwrap

 from . import test_projects, utils
@@ -8,10 +7,7 @@ basic_project = test_projects.new_c_project(
        """
        # Will fail if PEP 518 does work
        import requests
-        if sys.version_info < (3, 6, 0):
-            assert requests.__version__ == "2.22.0", "Requests found but wrong version ({0})".format(requests.__version__)
-        else:
-            assert requests.__version__ == "2.23.0", "Requests found but wrong version ({0})".format(requests.__version__)
+        assert requests.__version__ == "2.23.0", "Requests found but wrong version ({0})".format(requests.__version__)

        # Just making sure environment is still set
        import os
@@ -29,21 +25,20 @@ requires = [
    "setuptools >= 42",
    "setuptools_scm[toml]>=4.1.2",
    "wheel",
-    "requests==2.22.0; python_version<'3.6'",
-    "requests==2.23.0; python_version>='3.6'"
+    "requests==2.23.0"
 ]

 build-backend = "setuptools.build_meta"
 """


-def test_pep518(tmp_path):
+def test_pep518(tmp_path, build_frontend_env):

    project_dir = tmp_path / "project"
    basic_project.generate(project_dir)

    # build the wheels
-    actual_wheels = utils.cibuildwheel_run(project_dir)
+    actual_wheels = utils.cibuildwheel_run(project_dir, add_env=build_frontend_env)

    # check that the expected wheels are produced
    expected_wheels = utils.expected_wheels("spam", "0.1.0")
@@ -54,4 +49,12 @@ def test_pep518(tmp_path):
    assert not (project_dir / "42").exists()
    assert not (project_dir / "4.1.2").exists()

-    assert len(os.listdir(project_dir)) == len(basic_project.files)
+    # pypa/build creates a "build" folder & a "*.egg-info" folder for the wheel being built,
+    # this should be harmless so remove them
+    contents = [
+        item
+        for item in project_dir.iterdir()
+        if item.name != "build" and not item.name.endswith(".egg-info")
+    ]
+
+    assert len(contents) == len(basic_project.files)
@@ -1,2 +1,4 @@
-from .base import TestProject  # noqa
-from .c import new_c_project  # noqa
+from .base import TestProject
+from .c import new_c_project
+
+__all__ = ("TestProject", "new_c_project")
@@ -24,38 +24,18 @@ spam_system(PyObject *self, PyObject *args)
 }

 /* Module initialization */
-
-#if PY_MAJOR_VERSION >= 3
-    #define MOD_INIT(name) PyMODINIT_FUNC PyInit_##name(void)
-    #define MOD_DEF(m, name, doc, methods, module_state_size) \
-        static struct PyModuleDef moduledef = { \
-            PyModuleDef_HEAD_INIT, name, doc, module_state_size, methods, }; \
-        m = PyModule_Create(&moduledef);
-    #define MOD_RETURN(m) return m;
-#else
-    #define MOD_INIT(name) PyMODINIT_FUNC init##name(void)
-    #define MOD_DEF(m, name, doc, methods, module_state_size) \
-        m = Py_InitModule3(name, methods, doc);
-    #define MOD_RETURN(m) return;
-#endif
-
 static PyMethodDef module_methods[] = {
    {"system", (PyCFunction)spam_system, METH_VARARGS,
     "Execute a shell command."},
    {NULL}  /* Sentinel */
 };

-MOD_INIT(spam)
+PyMODINIT_FUNC PyInit_spam(void)
 {
-    PyObject* m;
-
-    MOD_DEF(m,
-            "spam",
-            "Example module",
-            module_methods,
-            -1)
-
-    MOD_RETURN(m)
+    static struct PyModuleDef moduledef = {
+        PyModuleDef_HEAD_INIT, "spam", "Example module", -1, module_methods,
+    };
+    return PyModule_Create(&moduledef);
 }
 """

@@ -7,15 +7,12 @@ project_with_ssl_tests = test_projects.new_c_project(
        r"""
        import ssl

-        if sys.version_info[0] == 2:
-            from urllib2 import urlopen
-        else:
-            from urllib.request import urlopen
+        from urllib.request import urlopen

        context = ssl.SSLContext(ssl.PROTOCOL_TLSv1_2)
        data = urlopen("https://www.nist.gov", context=context)
-        data = urlopen("https://raw.githubusercontent.com/pypa/cibuildwheel/master/CI.md", context=context)
-        data = urlopen("https://raw.githubusercontent.com/pypa/cibuildwheel/master/CI.md")
+        data = urlopen("https://raw.githubusercontent.com/pypa/cibuildwheel/main/CI.md", context=context)
+        data = urlopen("https://raw.githubusercontent.com/pypa/cibuildwheel/main/CI.md")
        """
    )
 )
@@ -10,7 +10,7 @@ project_with_a_test = test_projects.new_c_project(
    setup_cfg_add=textwrap.dedent(
        r"""
        [options.extras_require]
-        test = nose
+        test = pytest
        """
    )
 )
@@ -52,8 +52,7 @@ class TestSpam(TestCase):
        # sys.prefix is different from sys.base_prefix when running a virtualenv
        # See https://docs.python.org/3/library/venv.html, which virtualenv seems
        # to honor in recent releases
-        # Python 2 doesn't have sys.base_prefix by default
-        if not hasattr(sys, 'base_prefix') or sys.prefix == sys.base_prefix:
+        if sys.prefix == sys.base_prefix:
            self.fail("Not running in a virtualenv")

        self.assertTrue(path_contains(sys.prefix, sys.executable))
@@ -67,10 +66,6 @@ class TestSpam(TestCase):
        bits = struct.calcsize("P") * 8
        if bits == 32:
            self.assertEqual(platform.machine(), "i686")
-
-    def test_time_to_remove_the_pypy_venv_patch(self):
-        if sys.platform == "darwin":
-            assert not hasattr(sys, "pypy_version_info") or sys.pypy_version_info < (7,3,4)
 '''


@@ -82,11 +77,11 @@ def test(tmp_path):
    actual_wheels = utils.cibuildwheel_run(
        project_dir,
        add_env={
-            "CIBW_TEST_REQUIRES": "nose",
+            "CIBW_TEST_REQUIRES": "pytest",
            # the 'false ||' bit is to ensure this command runs in a shell on
            # mac/linux.
-            "CIBW_TEST_COMMAND": "false || nosetests {project}/test",
-            "CIBW_TEST_COMMAND_WINDOWS": "COLOR 00 || nosetests {project}/test",
+            "CIBW_TEST_COMMAND": "false || pytest {project}/test",
+            "CIBW_TEST_COMMAND_WINDOWS": "COLOR 00 || pytest {project}/test",
        },
    )

@@ -106,8 +101,8 @@ def test_extras_require(tmp_path):
            "CIBW_TEST_EXTRAS": "test",
            # the 'false ||' bit is to ensure this command runs in a shell on
            # mac/linux.
-            "CIBW_TEST_COMMAND": "false || nosetests {project}/test",
-            "CIBW_TEST_COMMAND_WINDOWS": "COLOR 00 || nosetests {project}/test",
+            "CIBW_TEST_COMMAND": "false || pytest {project}/test",
+            "CIBW_TEST_COMMAND_WINDOWS": "COLOR 00 || pytest {project}/test",
        },
    )

@@ -16,7 +16,7 @@ raise Exception('this build will fail')
 """


-def test_failed_project_with_so_files(tmp_path, capfd):
+def test_failed_project_with_so_files(tmp_path, capfd, build_frontend_env):
    if utils.platform != "linux":
        pytest.skip("this test is only relevant to the linux build")

@@ -24,7 +24,7 @@ def test_failed_project_with_so_files(tmp_path, capfd):
    so_file_project.generate(project_dir)

    with pytest.raises(subprocess.CalledProcessError):
-        utils.cibuildwheel_run(project_dir)
+        utils.cibuildwheel_run(project_dir, add_env=build_frontend_env)

    captured = capfd.readouterr()
    print("out", captured.out)
@@ -6,11 +6,9 @@ This file is added to the PYTHONPATH in the test runner at bin/run_test.py.

 import os
 import platform as pm
-import shutil
 import subprocess
 import sys
-from contextlib import contextmanager
-from tempfile import mkdtemp
+from tempfile import TemporaryDirectory

 platform: str

@@ -26,24 +24,17 @@ else:
    raise Exception("Unsupported platform")


-# Python 2 does not have a tempfile.TemporaryDirectory context manager
-@contextmanager
-def TemporaryDirectoryIfNone(path):
-    _path = path or mkdtemp()
-    try:
-        yield _path
-    finally:
-        if path is None:
-            shutil.rmtree(_path)
-
-
-def cibuildwheel_get_build_identifiers(project_path, env=None):
+def cibuildwheel_get_build_identifiers(project_path, env=None, *, prerelease_pythons=False):
    """
    Returns the list of build identifiers that cibuildwheel will try to build
    for the current platform.
    """
+    cmd = [sys.executable, "-m", "cibuildwheel", "--print-build-identifiers", str(project_path)]
+    if prerelease_pythons:
+        cmd.append("--prerelease-pythons")
+
    cmd_output = subprocess.run(
-        [sys.executable, "-m", "cibuildwheel", "--print-build-identifiers", str(project_path)],
+        cmd,
        universal_newlines=True,
        env=env,
        check=True,
@@ -76,21 +67,22 @@ def cibuildwheel_run(project_path, package_dir=".", env=None, add_env=None, outp
    if add_env is not None:
        env.update(add_env)

-    with TemporaryDirectoryIfNone(output_dir) as _output_dir:
+    with TemporaryDirectory() as tmp_output_dir:
        subprocess.run(
            [
                sys.executable,
                "-m",
                "cibuildwheel",
+                "--prerelease-pythons",
                "--output-dir",
-                str(_output_dir),
+                str(output_dir or tmp_output_dir),
                str(package_dir),
            ],
            env=env,
            cwd=project_path,
            check=True,
        )
-        wheels = os.listdir(_output_dir)
+        wheels = os.listdir(output_dir or tmp_output_dir)
    return wheels


@@ -113,8 +105,6 @@ def expected_wheels(
    manylinux_versions=None,
    macosx_deployment_target="10.9",
    machine_arch=None,
-    *,
-    exclude_27=platform == "windows",
 ):
    """
    Returns a list of expected wheels from a run of cibuildwheel.
@@ -129,28 +119,23 @@ def expected_wheels(

    if manylinux_versions is None:
        if machine_arch == "x86_64":
-            manylinux_versions = ["manylinux1", "manylinux2010"]
+            manylinux_versions = ["manylinux_2_5", "manylinux1", "manylinux_2_12", "manylinux2010"]
        else:
-            manylinux_versions = ["manylinux2014"]
+            manylinux_versions = ["manylinux_2_17", "manylinux2014"]

-    python_abi_tags = ["cp35-cp35m", "cp36-cp36m", "cp37-cp37m", "cp38-cp38", "cp39-cp39"]
+    python_abi_tags = ["cp36-cp36m", "cp37-cp37m", "cp38-cp38", "cp39-cp39", "cp310-cp310"]

-    if machine_arch in ["x86_64", "AMD64", "x86"]:
-        python_abi_tags += ["cp27-cp27m", "pp27-pypy_73", "pp36-pypy36_pp73", "pp37-pypy37_pp73"]
-
-        if platform == "linux":
-            python_abi_tags.append("cp27-cp27mu")  # python 2.7 has 2 different ABI on manylinux
+    if machine_arch in ["x86_64", "AMD64", "x86", "aarch64"]:
+        python_abi_tags += ["pp37-pypy37_pp73"]

    if platform == "macos" and get_macos_version() >= (10, 16):
        # 10.16 is sometimes reported as the macOS version on macOS 11.
-        # CPython 3.5 doesn't work on macOS 11.
-        python_abi_tags.remove("cp35-cp35m")
        # pypy not supported on macOS 11.
        python_abi_tags = [t for t in python_abi_tags if not t.startswith("pp")]

    if platform == "macos" and machine_arch == "arm64":
-        # currently, arm64 macs are only supported by cp39
-        python_abi_tags = ["cp39-cp39"]
+        # currently, arm64 macs are only supported by cp39 & cp310
+        python_abi_tags = ["cp39-cp39", "cp310-cp310"]

    wheels = []

@@ -160,20 +145,22 @@ def expected_wheels(
        if platform == "linux":
            architectures = [machine_arch]

-            if machine_arch == "x86_64" and python_abi_tag.startswith("cp"):
+            if machine_arch == "x86_64":
                architectures.append("i686")

            platform_tags = [
-                f"{manylinux_version}_{architecture}"
+                ".".join(
+                    f"{manylinux_version}_{architecture}"
+                    for manylinux_version in manylinux_versions
+                )
                for architecture in architectures
-                for manylinux_version in manylinux_versions
            ]

        elif platform == "windows":
            if python_abi_tag.startswith("cp"):
                platform_tags = ["win32", "win_amd64"]
            else:
-                platform_tags = ["win32"]
+                platform_tags = ["win_amd64"]

        elif platform == "macos":
            if python_abi_tag == "cp39-cp39" and machine_arch == "arm64":
@@ -195,11 +182,6 @@ def expected_wheels(
        for platform_tag in platform_tags:
            wheels.append(f"{package_name}-{package_version}-{python_abi_tag}-{platform_tag}.whl")

-    # Travis on Windows does not support using the default Python 2.7 compiler,
-    # so we support skipping here.
-    if exclude_27:
-        wheels = [w for w in wheels if "-cp27-" not in w and "-pp2" not in w]
-
    return wheels


@@ -11,7 +11,7 @@ def test_compare_configs():

    dict_txt = toml.loads(txt)

-    new_txt = toml.dumps(dict_txt, encoder=InlineArrayDictEncoder())
+    new_txt = toml.dumps(dict_txt, encoder=InlineArrayDictEncoder())  # type: ignore
    print(new_txt)

    assert new_txt == txt
@@ -35,6 +35,6 @@ python_configurations = [
 ]
 """

-    output = toml.dumps(example, encoder=InlineArrayDictEncoder())
+    output = toml.dumps(example, encoder=InlineArrayDictEncoder())  # type: ignore
    print(output)
    assert output == result
@@ -4,65 +4,85 @@ from cibuildwheel.util import BuildSelector


 def test_build():
-    build_selector = BuildSelector(build_config="cp3?-* *-manylinux1*", skip_config="")
+    build_selector = BuildSelector(build_config="cp3*-* *-manylinux*", skip_config="")

-    assert build_selector("cp27-manylinux1_x86_64")
-    assert build_selector("cp36-manylinux1_x86_64")
-    assert build_selector("cp37-manylinux1_x86_64")
-    assert build_selector("cp27-manylinux1_i686")
-    assert build_selector("cp36-manylinux1_i686")
-    assert build_selector("cp37-manylinux1_i686")
-    assert not build_selector("cp27-macosx_10_6_intel")
-    assert build_selector("cp36-macosx_10_6_intel")
-    assert build_selector("cp37-macosx_10_6_intel")
-    assert not build_selector("cp27-win32")
+    assert build_selector("cp36-manylinux_x86_64")
+    assert build_selector("cp37-manylinux_x86_64")
+    assert not build_selector("cp310-manylinux_x86_64")
+    assert build_selector("pp36-manylinux_x86_64")
+    assert build_selector("pp37-manylinux_x86_64")
+    assert build_selector("cp36-manylinux_i686")
+    assert build_selector("cp37-manylinux_i686")
+    assert build_selector("cp36-macosx_intel")
+    assert build_selector("cp37-macosx_intel")
+    assert build_selector("cp39-macosx_intel")
+    assert build_selector("cp39-macosx_universal2")
+    assert build_selector("cp39-macosx_arm64")
+    assert not build_selector("pp36-macosx_intel")
+    assert not build_selector("pp37-macosx_intel")
    assert build_selector("cp36-win32")
    assert build_selector("cp37-win32")
-    assert not build_selector("cp27-win_amd64")
+    assert not build_selector("pp36-win32")
+    assert not build_selector("pp37-win32")
    assert build_selector("cp36-win_amd64")
    assert build_selector("cp37-win_amd64")
+    assert not build_selector("cp310-win_amd64")
+    assert not build_selector("pp36-win_amd64")
+    assert not build_selector("pp37-win_amd64")
+
+
+def test_build_filter_pre():
+    build_selector = BuildSelector(
+        build_config="cp3*-* *-manylinux*",
+        skip_config="",
+        prerelease_pythons=True,
+    )
+
+    assert build_selector("cp37-manylinux_x86_64")
+    assert build_selector("cp310-manylinux_x86_64")
+    assert build_selector("cp37-win_amd64")
+    assert build_selector("cp310-win_amd64")


 def test_skip():
    build_selector = BuildSelector(
-        build_config="*", skip_config="cp27-* cp3?-manylinux1_i686 cp36-win* *-win32"
+        build_config="*", skip_config="pp36-* cp3?-manylinux_i686 cp36-win* *-win32"
    )

-    assert not build_selector("cp27-manylinux1_x86_64")
-    assert build_selector("cp36-manylinux1_x86_64")
-    assert build_selector("cp37-manylinux1_x86_64")
-    assert not build_selector("cp27-manylinux1_i686")
-    assert not build_selector("cp36-manylinux1_i686")
-    assert not build_selector("cp37-manylinux1_i686")
-    assert not build_selector("cp27-macosx_10_6_intel")
+    assert not build_selector("pp36-manylinux_x86_64")
+    assert build_selector("pp37-manylinux_x86_64")
+    assert build_selector("cp36-manylinux_x86_64")
+    assert build_selector("cp37-manylinux_x86_64")
+    assert not build_selector("cp36-manylinux_i686")
+    assert not build_selector("cp37-manylinux_i686")
+    assert not build_selector("pp36-macosx_10_6_intel")
+    assert build_selector("pp37-macosx_10_6_intel")
    assert build_selector("cp36-macosx_10_6_intel")
    assert build_selector("cp37-macosx_10_6_intel")
-    assert not build_selector("cp27-win32")
    assert not build_selector("cp36-win32")
    assert not build_selector("cp37-win32")
-    assert not build_selector("cp27-win_amd64")
    assert not build_selector("cp36-win_amd64")
    assert build_selector("cp37-win_amd64")


 def test_build_and_skip():
    build_selector = BuildSelector(
-        build_config="cp36-* cp37-macosx* *-manylinux1*", skip_config="cp27-* cp37-manylinux1_i686"
+        build_config="cp36-* cp37-macosx* *-manylinux*", skip_config="pp37-* cp37-manylinux_i686"
    )

-    assert not build_selector("cp27-manylinux1_x86_64")
-    assert build_selector("cp36-manylinux1_x86_64")
-    assert build_selector("cp37-manylinux1_x86_64")
-    assert not build_selector("cp27-manylinux1_i686")
-    assert build_selector("cp36-manylinux1_i686")
-    assert not build_selector("cp37-manylinux1_i686")
-    assert not build_selector("cp27-macosx_10_6_intel")
+    assert not build_selector("pp37-manylinux_x86_64")
+    assert build_selector("cp36-manylinux_x86_64")
+    assert build_selector("cp37-manylinux_x86_64")
+    assert not build_selector("pp37-manylinux_i686")
+    assert build_selector("cp36-manylinux_i686")
+    assert not build_selector("cp37-manylinux_i686")
+    assert not build_selector("pp37-macosx_10_6_intel")
    assert build_selector("cp36-macosx_10_6_intel")
    assert build_selector("cp37-macosx_10_6_intel")
-    assert not build_selector("cp27-win32")
+    assert not build_selector("pp37-win32")
    assert build_selector("cp36-win32")
    assert not build_selector("cp37-win32")
-    assert not build_selector("cp27-win_amd64")
+    assert not build_selector("pp37-win_amd64")
    assert build_selector("cp36-win_amd64")
    assert not build_selector("cp37-win_amd64")

@@ -70,49 +90,44 @@ def test_build_and_skip():
 def test_build_braces():
    build_selector = BuildSelector(build_config="cp{36,37}*", skip_config="")

-    assert not build_selector("cp27-manylinux1_x86_64")
-    assert build_selector("cp36-manylinux1_x86_64")
-    assert build_selector("cp37-manylinux1_x86_64")
-    assert not build_selector("cp38-manylinux1_x86_64")
-    assert not build_selector("cp39-manylinux1_x86_64")
+    assert build_selector("cp36-manylinux_x86_64")
+    assert build_selector("cp37-manylinux_x86_64")
+    assert not build_selector("cp38-manylinux_x86_64")
+    assert not build_selector("cp39-manylinux_x86_64")


 def test_build_limited_python():
    build_selector = BuildSelector(
-        build_config="*", skip_config="", requires_python=SpecifierSet(">=3.6")
+        build_config="*", skip_config="", requires_python=SpecifierSet(">=3.7")
    )

-    assert not build_selector("cp27-manylinux1_x86_64")
-    assert build_selector("cp36-manylinux1_x86_64")
-    assert build_selector("cp37-manylinux1_x86_64")
-    assert not build_selector("cp27-manylinux1_i686")
-    assert build_selector("cp36-manylinux1_i686")
-    assert build_selector("cp37-manylinux1_i686")
-    assert not build_selector("cp27-win32")
-    assert build_selector("cp36-win32")
+    assert not build_selector("cp36-manylinux_x86_64")
+    assert build_selector("cp37-manylinux_x86_64")
+    assert build_selector("cp38-manylinux_x86_64")
+    assert not build_selector("cp36-manylinux_i686")
+    assert build_selector("cp37-manylinux_i686")
+    assert build_selector("cp38-manylinux_i686")
+    assert not build_selector("cp36-win32")
    assert build_selector("cp37-win32")
-    assert not build_selector("pp27-win32")
-    assert build_selector("pp36-win32")
-    assert build_selector("pp37-win32")
+    assert build_selector("cp38-win32")
+    assert build_selector("pp37-win_amd64")


 def test_build_limited_python_partial():
    build_selector = BuildSelector(
-        build_config="*",
-        skip_config="",
-        requires_python=SpecifierSet(">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, !=3.5.*"),
+        build_config="*", skip_config="", requires_python=SpecifierSet(">=3.6, !=3.7.*")
    )

-    assert build_selector("cp27-manylinux1_x86_64")
-    assert not build_selector("cp35-manylinux1_x86_64")
-    assert build_selector("cp36-manylinux1_x86_64")
+    assert build_selector("cp36-manylinux_x86_64")
+    assert not build_selector("cp37-manylinux_x86_64")
+    assert build_selector("cp38-manylinux_x86_64")
+    assert build_selector("cp39-manylinux_x86_64")


 def test_build_limited_python_patch():
    build_selector = BuildSelector(
-        build_config="*", skip_config="", requires_python=SpecifierSet(">=2.7.9")
+        build_config="*", skip_config="", requires_python=SpecifierSet(">=3.6.8")
    )

-    assert build_selector("cp27-manylinux1_x86_64")
-    assert build_selector("cp36-manylinux1_x86_64")
-    assert build_selector("cp37-manylinux1_x86_64")
+    assert build_selector("cp36-manylinux_x86_64")
+    assert build_selector("cp37-manylinux_x86_64")
@@ -19,9 +19,3 @@ def test_defaults():
    assert dependency_constraints.get_for_python_version("3.6").samefile(
        resources_dir / "constraints-python36.txt"
    )
-    assert dependency_constraints.get_for_python_version("3.5").samefile(
-        resources_dir / "constraints-python35.txt"
-    )
-    assert dependency_constraints.get_for_python_version("2.7").samefile(
-        resources_dir / "constraints-python27.txt"
-    )
@@ -63,6 +63,7 @@ def test_container_removed():
            stdout=subprocess.PIPE,
            universal_newlines=True,
        ).stdout
+        assert container.name is not None
        assert container.name in docker_containers_listing
        old_container_name = container.name

@@ -106,10 +106,12 @@ def test_substitution_with_backslash():

 def test_awkwardly_quoted_variable():
    environment_recipe = parse_environment(
-        'VAR2=something"like this""$VAR1"$VAR1$(echo "theres more")"$(echo "and more!")"'
+        'VAR2=something"like this""$VAR1"$VAR1$(echo "there is more")"$(echo "and more!")"'
    )

    # pass the existing process env so PATH is available
    environment_dict = environment_recipe.as_dictionary({"VAR1": "but wait"})

-    assert environment_dict.get("VAR2") == "somethinglike thisbut waitbut waittheres moreand more!"
+    assert (
+        environment_dict.get("VAR2") == "somethinglike thisbut waitbut waitthere is moreand more!"
+    )
@@ -81,10 +81,11 @@ def test_empty_selector(platform, intercepted_build_args, monkeypatch):
        ("i686", "manylinux2014", "quay.io/pypa/manylinux2014_i686:*"),
        ("i686", "manylinux_2_24", "quay.io/pypa/manylinux_2_24_i686:*"),
        ("i686", "custom_image", "custom_image"),
-        ("pypy_x86_64", None, "pypywheels/manylinux2010-pypy_x86_64:*"),
+        ("pypy_x86_64", None, "quay.io/pypa/manylinux2010_x86_64:*"),
        ("pypy_x86_64", "manylinux1", "manylinux1"),  # Does not exist
-        ("pypy_x86_64", "manylinux2010", "pypywheels/manylinux2010-pypy_x86_64:*"),
-        ("pypy_x86_64", "manylinux2014", "manylinux2014"),  # Does not exist (yet)
+        ("pypy_x86_64", "manylinux2010", "quay.io/pypa/manylinux2010_x86_64:*"),
+        ("pypy_x86_64", "manylinux2014", "quay.io/pypa/manylinux2014_x86_64:*"),
+        ("pypy_x86_64", "manylinux_2_24", "quay.io/pypa/manylinux_2_24_x86_64:*"),
        ("pypy_x86_64", "custom_image", "custom_image"),
    ],
 )
@@ -199,7 +200,7 @@ def test_test_command(

    main()

-    assert intercepted_build_args.args[0].test_command == test_command
+    assert intercepted_build_args.args[0].test_command == (test_command or "")


@pytest.mark.parametrize("before_build", [None, "before --build"])
@@ -216,7 +217,7 @@ def test_before_build(

    main()

-    assert intercepted_build_args.args[0].before_build == before_build
+    assert intercepted_build_args.args[0].before_build == (before_build or "")


@pytest.mark.parametrize("build_verbosity", [None, 0, 2, -2, 4, -4])
@@ -237,35 +238,40 @@ def test_build_verbosity(
    assert intercepted_build_args.args[0].build_verbosity == expected_verbosity


-@pytest.mark.parametrize("option_name", ["CIBW_BUILD", "CIBW_SKIP"])
@pytest.mark.parametrize(
-    "option_value, build_selector_patterns",
+    "selector",
    [
-        ("*-manylinux1_*", ["*-manylinux_*"]),
-        ("*-macosx_10_6_intel", ["*-macosx_x86_64"]),
-        ("*-macosx_10_9_x86_64", ["*-macosx_x86_64"]),
-        ("cp37-macosx_10_9_x86_64", ["cp37-macosx_x86_64"]),
+        "CIBW_BUILD",
+        "CIBW_SKIP",
+        "CIBW_TEST_SKIP",
    ],
 )
-def test_build_selector_migrations(
-    intercepted_build_args,
-    monkeypatch,
-    option_name,
-    option_value,
-    build_selector_patterns,
-    allow_empty,
+@pytest.mark.parametrize(
+    "pattern",
+    [
+        "cp27-*",
+        "cp35-*",
+        "?p27*",
+        "?p2*",
+        "?p35*",
+    ],
+)
+def test_build_selector_deprecated_error(
+    monkeypatch, platform, intercepted_build_args, selector, pattern, allow_empty, capsys
 ):
-    monkeypatch.setenv(option_name, option_value)
+    monkeypatch.setenv(selector, pattern)

-    main()
+    if selector == "CIBW_BUILD":
+        with pytest.raises(SystemExit) as ex:
+            main()
+        assert ex.value.code == 4

-    intercepted_build_selector = intercepted_build_args.args[0].build_selector
-    assert isinstance(intercepted_build_selector, BuildSelector)
-
-    if option_name == "CIBW_BUILD":
-        assert intercepted_build_selector.build_patterns == build_selector_patterns
    else:
-        assert intercepted_build_selector.skip_patterns == build_selector_patterns
+        main()
+
+    stderr = capsys.readouterr().err
+    msg = f"cibuildwheel 2.x no longer supports Python < 3.6. Please use the 1.x series or update {selector}"
+    assert msg in stderr


@pytest.mark.parametrize("before_all", ["", None, "test text"])
@@ -280,7 +286,4 @@ def test_before_all(before_all, platform_specific, platform, intercepted_build_a

    main()

-    if before_all is None:
-        before_all = ""
-
-    assert intercepted_build_args.args[0].before_all == before_all
+    assert intercepted_build_args.args[0].before_all == (before_all or "")
@@ -0,0 +1,190 @@
+import pytest
+
+from cibuildwheel.options import ConfigOptionError, ConfigOptions
+
+PYPROJECT_1 = """
+[tool.cibuildwheel]
+build = "cp39*"
+environment = {THING = "OTHER", FOO="BAR"}
+
+test-command = "pyproject"
+test-requires = "something"
+test-extras = ["one", "two"]
+
+manylinux-x86_64-image = "manylinux1"
+
+[tool.cibuildwheel.macos]
+test-requires = "else"
+
+[tool.cibuildwheel.linux]
+test-requires = ["other", "many"]
+"""
+
+
+@pytest.fixture(params=["linux", "macos", "windows"])
+def platform(request):
+    return request.param
+
+
+@pytest.mark.parametrize("fname", ["pyproject.toml", "cibuildwheel.toml"])
+def test_simple_settings(tmp_path, platform, fname):
+    with tmp_path.joinpath(fname).open("w") as f:
+        f.write(PYPROJECT_1)
+
+    options = ConfigOptions(tmp_path, f"{{package}}/{fname}", platform=platform)
+
+    assert options("build", env_plat=False, sep=" ") == "cp39*"
+
+    assert options("test-command") == "pyproject"
+    assert options("archs", sep=" ") == "auto"
+    assert (
+        options("test-requires", sep=" ")
+        == {"windows": "something", "macos": "else", "linux": "other many"}[platform]
+    )
+
+    # Also testing options for support for both lists and tables
+    assert (
+        options("environment", table={"item": '{k}="{v}"', "sep": " "}) == 'THING="OTHER" FOO="BAR"'
+    )
+    assert (
+        options("environment", sep="x", table={"item": '{k}="{v}"', "sep": " "})
+        == 'THING="OTHER" FOO="BAR"'
+    )
+    assert options("test-extras", sep=",") == "one,two"
+    assert options("test-extras", sep=",", table={"item": '{k}="{v}"', "sep": " "}) == "one,two"
+
+    assert options("manylinux-x86_64-image") == "manylinux1"
+    assert options("manylinux-i686-image") == "manylinux2010"
+
+    with pytest.raises(ConfigOptionError):
+        options("environment", sep=" ")
+
+    with pytest.raises(ConfigOptionError):
+        options("test-extras", table={"item": '{k}="{v}"', "sep": " "})
+
+
+def test_envvar_override(tmp_path, platform, monkeypatch):
+    monkeypatch.setenv("CIBW_BUILD", "cp38*")
+    monkeypatch.setenv("CIBW_MANYLINUX_X86_64_IMAGE", "manylinux2014")
+    monkeypatch.setenv("CIBW_TEST_COMMAND", "mytest")
+    monkeypatch.setenv("CIBW_TEST_REQUIRES", "docs")
+    monkeypatch.setenv("CIBW_TEST_REQUIRES_LINUX", "scod")
+
+    with tmp_path.joinpath("pyproject.toml").open("w") as f:
+        f.write(PYPROJECT_1)
+
+    options = ConfigOptions(tmp_path, platform=platform)
+
+    assert options("archs", sep=" ") == "auto"
+
+    assert options("build", sep=" ") == "cp38*"
+    assert options("manylinux-x86_64-image") == "manylinux2014"
+    assert options("manylinux-i686-image") == "manylinux2010"
+
+    assert (
+        options("test-requires", sep=" ")
+        == {"windows": "docs", "macos": "docs", "linux": "scod"}[platform]
+    )
+    assert options("test-command") == "mytest"
+
+
+def test_project_global_override_default_platform(tmp_path, platform):
+    tmp_path.joinpath("pyproject.toml").write_text(
+        """
+[tool.cibuildwheel]
+repair-wheel-command = "repair-project-global"
+"""
+    )
+    options = ConfigOptions(tmp_path, platform=platform)
+    assert options("repair-wheel-command") == "repair-project-global"
+
+
+def test_env_global_override_default_platform(tmp_path, platform, monkeypatch):
+    monkeypatch.setenv("CIBW_REPAIR_WHEEL_COMMAND", "repair-env-global")
+    options = ConfigOptions(tmp_path, platform=platform)
+    assert options("repair-wheel-command") == "repair-env-global"
+
+
+def test_env_global_override_project_platform(tmp_path, platform, monkeypatch):
+    monkeypatch.setenv("CIBW_REPAIR_WHEEL_COMMAND", "repair-env-global")
+    tmp_path.joinpath("pyproject.toml").write_text(
+        """
+[tool.cibuildwheel.linux]
+repair-wheel-command = "repair-project-linux"
+[tool.cibuildwheel.windows]
+repair-wheel-command = "repair-project-windows"
+[tool.cibuildwheel.macos]
+repair-wheel-command = "repair-project-macos"
+"""
+    )
+    options = ConfigOptions(tmp_path, platform=platform)
+    assert options("repair-wheel-command") == "repair-env-global"
+
+
+def test_global_platform_order(tmp_path, platform):
+    tmp_path.joinpath("pyproject.toml").write_text(
+        """
+[tool.cibuildwheel.linux]
+repair-wheel-command = "repair-project-linux"
+[tool.cibuildwheel.windows]
+repair-wheel-command = "repair-project-windows"
+[tool.cibuildwheel.macos]
+repair-wheel-command = "repair-project-macos"
+[tool.cibuildwheel]
+repair-wheel-command = "repair-project-global"
+"""
+    )
+    options = ConfigOptions(tmp_path, platform=platform)
+    assert options("repair-wheel-command") == f"repair-project-{platform}"
+
+
+def test_unexpected_key(tmp_path):
+    # Note that platform contents are only checked when running
+    # for that platform.
+    tmp_path.joinpath("pyproject.toml").write_text(
+        """
+[tool.cibuildwheel]
+repairs-wheel-command = "repair-project-linux"
+"""
+    )
+
+    with pytest.raises(ConfigOptionError):
+        ConfigOptions(tmp_path, platform="linux")
+
+
+def test_unexpected_table(tmp_path):
+    tmp_path.joinpath("pyproject.toml").write_text(
+        """
+[tool.cibuildwheel.linus]
+repair-wheel-command = "repair-project-linux"
+"""
+    )
+    with pytest.raises(ConfigOptionError):
+        ConfigOptions(tmp_path, platform="linux")
+
+
+def test_unsupported_join(tmp_path):
+    tmp_path.joinpath("pyproject.toml").write_text(
+        """
+[tool.cibuildwheel]
+build = ["1", "2"]
+"""
+    )
+    options = ConfigOptions(tmp_path, platform="linux")
+
+    assert "1, 2" == options("build", sep=", ")
+    with pytest.raises(ConfigOptionError):
+        options("build")
+
+
+def test_disallowed_a(tmp_path):
+    tmp_path.joinpath("pyproject.toml").write_text(
+        """
+[tool.cibuildwheel.windows]
+manylinux-x64_86-image = "manylinux1"
+"""
+    )
+    disallow = {"windows": {"manylinux-x64_86-image"}}
+    ConfigOptions(tmp_path, platform="linux", disallow=disallow)
+    with pytest.raises(ConfigOptionError):
+        ConfigOptions(tmp_path, platform="windows", disallow=disallow)