Bump version: v4.0.0rc2

fix: remove potential partial extraction in case of error

Co-authored-by: Copilot <198982749+Copilot@users.noreply.github.com>

.agents/skills/changelog-entry/SKILL.md

@@ -0,0 +1,122 @@
+---
+name: changelog-entry
+description: Generate a new changelog entry for cibuildwheel based on all changes since the last tag. Use when updating the changelog or preparing a release.
+---
+
+# Generate Changelog Entry
+
+Produce a new version section at the top of `docs/changelog.md` summarizing all changes since the last git tag.
+
+## Steps
+
+1. **Find the last tag** — run `git tag --sort=-version:refname | head -1` to get the most recent version tag.
+2. **Gather changes** — run `git log <last-tag>..HEAD --oneline` and `git log <last-tag>..HEAD --format="%H %s"` to see all commits since that tag.
+3. **Read each merge/commit** — for substantive commits, read the full message and any linked PRs to understand the change. Use `git log <last-tag>..HEAD --format="---%n%B"` for full messages. If a commit message is ambiguous, use `gh pr view <number>` to get richer context from GitHub.
+4. **Classify and draft entries** — assign each change an emoji and write a one-line description following the style rules below. Combine related small PRs of the same type (bot dependency updates, dependabot CI action bumps, pre-commit autoupdates) into a single entry listing all PR numbers. Skip meta-changelog PRs (e.g., "Add missing CHANGELOG entries") — they don't describe user-facing changes. If a bot/dependency PR contains a substantive fix mixed in (e.g., a pip revert inside a dependency update), split it: mention the fix separately under its own category.
+5. **Determine the new version number** — inspect commits for breaking changes or new features to decide patch/minor/major bump. Ask the user if unclear.
+6. **Determine the date** — use today's date.
+7. **Insert the new section** — add it at the top of `docs/changelog.md`, right after the `# Changelog` heading and a blank line, before any existing version sections.
+
+## Style Rules
+
+These are non-negotiable formatting conventions derived from the existing changelog.
+
+### Version heading
+
+```markdown
+### v3.4.2
+```
+
+`###` heading, `v` prefix, full semver.
+
+### Date line
+
+```markdown
+_14 May 2026_
+```
+
+Italic (underscore-wrapped), day without leading zero, full month name, 4-digit year. One blank line after the date.
+
+### Entry format
+
+```markdown
+- <emoji> <Description> (#<PR number>)
+```
+
+- Each entry is a single bullet starting with `- `.
+- Emoji immediately after the dash-space.
+- Space between emoji and description text.
+- PR number(s) in parens at end: `(#1234)` or `(#1234, #5678)`.
+- No trailing period for single-sentence entries.
+- Period at end of multi-sentence entries only.
+
+### Emoji categories
+
+Use exactly one emoji per entry, chosen by category:
+
+| Emoji | Category | Used for |
+|-------|----------|----------|
+| 🌟 | Major feature | New platforms, significant new capabilities |
+| ✨ | Feature | New features, additions, user-visible enhancements |
+| 🐛 | Bug fix | Bug fixes |
+| 🛠 | Maintenance | Dep updates, internal improvements, behavior tweaks |
+| ⚠️ | Warning | Deprecations, breaking changes, dropped support |
+| 📚 | Docs | Documentation changes |
+| 💼 | Internal | Non-user-facing infra/tooling changes |
+| 🧪 | Tests | Test changes |
+| 🔐 | Security | Security-related changes (used in past changelogs) |
+
+### Category disambiguation
+
+When a change could fit multiple categories, use these tiebreakers:
+
+- **CI/workflow fixes** → 💼 (not 🧪) — they fix infra, not test logic.
+- **Test suite changes** → 🧪 — only for changes to the test code itself.
+- **Diagnostic output changes** (e.g., printing more info during builds) → 🛠 (not 🐛) — they're improvements, not bug fixes.
+- **A bug fix that also changes test code** → 🐛 — the user-facing fix takes priority; test changes are implicit.
+
+### Writing style
+
+- **Present tense**: "Adds", "Fixes", "Updates", not "Added", "Fixed".
+- **Sentence case**: capitalize only the first word after the emoji.
+- **Link option names to docs**: `[`option-name`](https://cibuildwheel.pypa.io/en/stable/options/#option-name)`. Option anchors match the option name — verify in `docs/options.md` by searching for `{: #option-name }`.
+- Be specific about what changed and why, not just that something changed.
+
+### Ordering
+
+Within a version section, order entries by importance:
+
+1. 🌟 entries first
+2. ⚠️ entries next
+3. ✨ entries
+4. 🐛 entries
+5. 🛠 entries
+6. 📚 entries
+7. 💼 entries
+8. 🧪 entries last
+
+### Multi-line entries
+
+For complex features needing explanation, use an indented italic paragraph:
+
+```markdown
+- ✨ Short summary here. (#1234)
+
+    _Longer explanation with details and caveats._ (#1234)
+```
+
+Adding a new Python beta version always has a specific longer explanation, check for a previous addition (like 3.14) for the note to use.
+
+### Blank lines
+
+- One blank line between version sections.
+- No blank lines between bullets within a version.
+
+## Validation
+
+After inserting the new section:
+
+1. Check that the new section follows all style rules above.
+2. Verify PR numbers match actual PRs in the commit log.
+3. Ensure no duplicate entries — multiple commits to the same PR should produce one entry.
+4. Run a final review of the file to confirm formatting is consistent with surrounding entries.

.github/workflows/copilot-setup-steps.yml

@@ -0,0 +1,40 @@
+name: "Copilot Setup Steps"
+
+permissions: {}
+
+on:
+  workflow_dispatch:
+  push:
+    paths:
+      - .github/workflows/copilot-setup-steps.yml
+  pull_request:
+    paths:
+      - .github/workflows/copilot-setup-steps.yml
+
+jobs:
+  copilot-setup-steps:
+    name: Copilot Setup Steps
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+
+      - uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
+        with:
+          python-version: "3.x"
+          allow-prereleases: true
+
+      - uses: astral-sh/setup-uv@08807647e7069bb48b6ef5acd8ec9567f424441b # v8.1.0
+
+      - name: Install tooling
+        run: |
+          uv tool install nox
+          uv tool install prek
+
+      - name: Pre-install checks
+        run: |
+          prek prepare-hooks

.github/workflows/release.yml

@@ -17,7 +17,7 @@ jobs:
       with:
         persist-credentials: false
 
-    - uses: hynek/build-and-inspect-python-package@fe0a0fb1925ca263d076ca4f2c13e93a6e92a33e # v2.17.0
+    - uses: hynek/build-and-inspect-python-package@d44ca7d91762de7a7d5436ddae667c6da6d1c3df # v2.18.0
 
   publish:
     needs: [dist]

.github/workflows/test.yml

@@ -46,7 +46,7 @@ jobs:
       with:
         python-version: "3.x"
     - uses: astral-sh/setup-uv@08807647e7069bb48b6ef5acd8ec9567f424441b # v8.1.0
-    - uses: j178/prek-action@6ad80277337ad479fe43bd70701c3f7f8aa74db3 # v2.0.3
+    - uses: j178/prek-action@bdca6f102f98e2b4c7029491a53dfd366469e33d # v2.0.4
     - name: PyLint checks
       run: uvx nox -s pylint -- --output-format=github
 

.github/workflows/update-dependencies.yml

@@ -28,12 +28,14 @@ jobs:
 
     # we use this step to grab a Github App auth token, so that PRs generated by this workflow
     # run the GHA tests.
-    - uses: actions/create-github-app-token@1b10c78c7865c340bc4f6099eb2f838309f1e8c3 # v3.1.1
+    - uses: actions/create-github-app-token@bcd2ba49218906704ab6c1aa796996da409d3eb1 # v3.2.0
       id: generate-token
       if: github.ref == 'refs/heads/main' && github.repository == 'pypa/cibuildwheel'
       with:
-        app-id: ${{ secrets.CIBUILDWHEEL_BOT_APP_ID }}
+        client-id: ${{ secrets.CIBUILDWHEEL_BOT_APP_ID }}
         private-key: ${{ secrets.CIBUILDWHEEL_BOT_APP_PRIVATE_KEY }}
+        permission-contents: write
+        permission-pull-requests: write
 
     - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       with:

.github/workflows/zizmor.yml

@@ -21,4 +21,4 @@ jobs:
           persist-credentials: false
 
       - name: Run zizmor 🌈
-        uses: zizmorcore/zizmor-action@b1d7e1fb5de872772f31590499237e7cce841e8e # v0.5.3
+        uses: zizmorcore/zizmor-action@5f14fd08f7cf1cb1609c1e344975f152c7ee938d # v0.5.6

.gitignore

@@ -119,3 +119,6 @@ site/
 
 # OS files
 .DS_Store
+
+# This file should be a symlink or contain "See @AGENTS.md"
+CLAUDE.md

.gitlab-ci.yml

@@ -1,5 +1,5 @@
 linux:
-  image: python:3.12
+  image: python:3.13
   services:
     - name: docker:dind
       entrypoint: ["env", "-u", "DOCKER_HOST"]
@@ -14,7 +14,7 @@ linux:
     # (comment the below line in a PR to debug a Gitlab-specific issue)
     PYTEST_ADDOPTS: -k "unit_test or test_0_basic" --suppress-no-test-exit-code
   rules:
-    - if: '$CI_COMMIT_BRANCH == "main"'
+    - if: '$CI_COMMIT_BRANCH == "main" || $CI_COMMIT_BRANCH =~ /^gitlab/'
       variables:
         CIBW_ENABLE: "all"
   script:
@@ -25,28 +25,29 @@ linux:
     - python ./bin/run_tests.py
 
 windows:
-  image: mcr.microsoft.com/windows/servercore:1809
   variables:
     PYTEST_ADDOPTS: -k "unit_test or test_0_basic" --suppress-no-test-exit-code
-  before_script:
-    - choco install python -y --allow-downgrade --version 3.12.4
   rules:
-    - if: '$CI_COMMIT_BRANCH == "main"'
+    - if: '$CI_COMMIT_BRANCH == "main" || $CI_COMMIT_BRANCH =~ /^gitlab/'
       variables:
-        CIBW_ENABLE: "all"
+        # Everything except graalpy. GraalPy is JVM-based and very slow to
+        # start; on the small (2-core) GitLab SaaS Windows runners,
+        # virtualenv's interpreter query for graalpy.exe times out, failing
+        # the build. (Other platforms run the full "all" group.)
+        CIBW_ENABLE: "cpython-prerelease pypy pypy-eol pyodide-eol pyodide-prerelease"
   script:
-    - py -m pip install -U pip
-    - py -m pip install -e. pytest-custom-exit-code --group test
-    - py bin\run_tests.py
+    - python -m pip install -U pip
+    - python -m pip install -e. pytest-custom-exit-code --group test
+    - python bin\run_tests.py
   tags:
     - saas-windows-medium-amd64
 
 macos:
-  image: macos-14-xcode-15
+  image: macos-15-xcode-16
   variables:
     PYTEST_ADDOPTS: -k "unit_test or test_0_basic" --suppress-no-test-exit-code
   rules:
-    - if: '$CI_COMMIT_BRANCH == "main"'
+    - if: '$CI_COMMIT_BRANCH == "main" || $CI_COMMIT_BRANCH =~ /^gitlab/'
       variables:
         CIBW_ENABLE: "all"
   script:

.pre-commit-config.yaml

@@ -1,5 +1,6 @@
 ci:
   autoupdate_schedule: monthly
+exclude: "^cibuildwheel/resources/ios-support/(?!make_cross_venv\\.py)"
 
 repos:
 - repo: https://github.com/pre-commit/pre-commit-hooks
@@ -17,14 +18,14 @@ repos:
     exclude: ^cibuildwheel/resources/android/android.patch$
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: 6fec9b7edb08fd9989088709d864a7826dc74e80  # frozen: v0.15.12
+  rev: 0671d8ab202c4ac093b78433ae5baf74f3fc7246  # frozen: v0.15.15
   hooks:
   - id: ruff-check
     args: ["--fix"]
   - id: ruff-format
 
 - repo: https://github.com/pre-commit/mirrors-mypy
-  rev: fc0f09a29bb495f4a91f00266155d6282d52485d  # frozen: v1.20.2
+  rev: d2823d321df3af8f878f7ee3414dc94d037145b9  # frozen: v2.1.0
   hooks:
   - id: mypy
     name: mypy 3.11 on cibuildwheel/
@@ -38,7 +39,6 @@ repos:
       - nox>=2025.2.9
       - orjson
       - packaging
-      - pyelftools
       - pygithub
       - pytest
       - rich

AGENTS.md

@@ -0,0 +1,57 @@
+# cibuildwheel — Agent Notes
+
+## Always run
+
+- `prek -a` should be run after changes to reformat, lint, and type check
+
+## Developer commands
+- `uv run pytest unit_test` — Quick run for unit tests
+- `nox -s tests` — run doctests + unit tests + integration tests (slow, >30 min, requires system Python installs on macOS).
+- `nox -s tests -- unit_test` — fast unit tests only.
+- `nox -s tests -- test -k before_build` — single integration test/file via pytest `-k`.
+- `nox -s lint` — run all linters (pre-commit/prek).
+- `nox -s pylint` — run pylint separately (not in pre-commit).
+- `nox -s docs` — mkdocs serve (interactive) or build (non-interactive).
+- Set up local dev env at `.venv`: `uv sync` (dependency groups used).
+
+## Project layout
+- `cibuildwheel/` — main package. Entry point: `cibuildwheel.__main__:main`.
+- `test/` — **integration tests** (expensive, run actual wheel builds).
+- `unit_test/` — **unit tests** (fast, no wheel builds).
+- `bin/` — maintainer scripts (update pins, generate README tables, schema, etc.).
+- `docs/` — mkdocs source.
+
+## Testing specifics
+- Three test suites exist, run in this order by `bin/run_tests.py`:
+  1. `pytest cibuildwheel` — doctests.
+  2. `pytest unit_test [...]` — unit tests.
+  3. `pytest test [...]` — integration tests (split into `serial` and `not serial` runs).
+- Serial integration tests **must not** run in parallel; non-serial use pytest-xdist by default.
+- Custom pytest options:
+  - `--run-docker` (unit_test + test): run OCI container tests. Linux only.
+  - `--run-podman`: run podman tests (Linux).
+  - `--run-emulation` (test): run QEMU emulation tests (e.g., `--run-emulation aarch64`).
+  - `--platform linux` (test): force integration tests to target Linux container builds even on macOS/Windows.
+  - `--enable` (test): sets `CIBW_ENABLE` env var (e.g., `pypy`, `graalpy`).
+- Integration tests auto-set a default `CIBW_ENABLE` if the env var is absent.
+- The `build_frontend_env` fixture parameterizes over `pip`, `build`, `build[uv]`, `uv` and skips unsupported combos per platform.
+- Some integration tests require system Python.org installs on macOS; missing them prints a download URL in the error.
+- iOS/Android/pyodide tests have dedicated pytest marks (`ios`, `android`, `pyodide`) and need platform-specific runners/simulators.
+
+## Lint / typecheck
+- Ruff (lint + format) and mypy run via pre-commit. Pylint runs separately via `nox -s pylint`.
+- Mypy is strict (`strict = true`) and targets Python 3.11 for the package, 3.14 for a second check in pre-commit.
+- Ruff config in `pyproject.toml` (`line-length = 100`).
+- Python 3.11 is the minimum supported version for the package itself.
+
+## Generated / maintained files
+- `README.md` contains two **cog-generated** tables (options table, changelog preview). Pre-commit runs `cog -c -P -r -I ./bin README.md`. Edit the source scripts (`bin/readme_*.py`) or the upstream files (`docs/options.md`, `docs/changelog.md`) — do not hand-edit the generated blocks. Note the identifier is _not_ cog generated, and can be edited.
+- `cibuildwheel/resources/cibuildwheel.schema.json` is generated by `bin/generate_schema.py` (run via `nox -s generate_schema`).
+- `cibuildwheel/resources/constraints-*.txt` are generated via `nox -s update_constraints`.
+- `cibuildwheel/resources/pinned_docker_images.cfg` and other resource files are updated via `nox -s update_pins`.
+
+## CI / release quirks
+- CI uses `uv sync --no-dev --group test` for test installs, then `uv run --no-sync` to execute.
+- The release workflow uses `hynek/build-and-inspect-python-package` for dist building.
+- `test.yml` skips unrelated paths to avoid burning CI time on docs-only changes.
+- A sample project artifact is built once and downloaded by downstream test jobs to avoid redundant work.

README.md

@@ -24,13 +24,13 @@ While cibuildwheel itself requires a recent Python version to run (we support th
 
 |                          | macOS Intel | macOS Apple Silicon | Windows 64bit | Windows 32bit | Windows Arm64  | manylinux<br/>musllinux x86_64 | manylinux<br/>musllinux i686 | manylinux<br/>musllinux aarch64 | manylinux<br/>musllinux ppc64le | manylinux<br/>musllinux s390x | manylinux<br/>musllinux armv7l | Android | iOS | Pyodide        |
 | ------------------------ | ----------- | ------------------- | ------------- | ------------- | -------------- | ------------------------------ | ---------------------------- | ------------------------------- | ------------------------------- | ----------------------------- | ------------------------------ | ------- | --- | -------------- |
-| CPython 3.9              | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>4</sup>                 | N/A     | N/A | N/A            |
-| CPython 3.10             | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>4</sup>                 | N/A     | N/A | N/A            |
-| CPython 3.11             | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>4</sup>                 | N/A     | N/A | N/A            |
-| CPython 3.12             | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>4</sup>                 | N/A     | N/A | ✅<sup>3</sup> |
-| CPython 3.13             | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>4</sup>                 | ✅      | ✅  | ✅<sup>3</sup> |
-| CPython 3.14             | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>4</sup>                 | ✅      | ✅  | N/A            |
-| CPython 3.15<sup>5</sup> | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>4</sup>                 | N/A     | N/A | N/A            |
+| CPython 3.9              | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>5</sup>                 | N/A     | N/A | N/A            |
+| CPython 3.10             | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>5</sup>                 | N/A     | N/A | N/A            |
+| CPython 3.11             | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>5</sup>                 | N/A     | N/A | N/A            |
+| CPython 3.12             | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>5</sup>                 | N/A     | N/A | ✅<sup>3</sup> |
+| CPython 3.13             | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>5</sup>                 | ✅      | ✅  | ✅             |
+| CPython 3.14             | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>5</sup>                 | ✅      | ✅  | ✅<sup>4</sup> |
+| CPython 3.15<sup>6</sup> | ✅          | ✅                  | ✅            | ✅            | ✅<sup>2</sup> | ✅                             | ✅                           | ✅                              | ✅                              | ✅                            | ✅<sup>5</sup>                 | ✅      | ✅  | N/A            |
 | PyPy 3.9 v7.3            | ✅          | ✅                  | ✅            | N/A           | N/A            | ✅<sup>1</sup>                 | ✅<sup>1</sup>               | ✅<sup>1</sup>                  | N/A                             | N/A                           | N/A                            | N/A     | N/A | N/A            |
 | PyPy 3.10 v7.3           | ✅          | ✅                  | ✅            | N/A           | N/A            | ✅<sup>1</sup>                 | ✅<sup>1</sup>               | ✅<sup>1</sup>                  | N/A                             | N/A                           | N/A                            | N/A     | N/A | N/A            |
 | PyPy 3.11 v7.3           | ✅          | ✅                  | ✅            | N/A           | N/A            | ✅<sup>1</sup>                 | ✅<sup>1</sup>               | ✅<sup>1</sup>                  | N/A                             | N/A                           | N/A                            | N/A     | N/A | N/A            |
@@ -39,13 +39,15 @@ While cibuildwheel itself requires a recent Python version to run (we support th
 
 <sup>**1** PyPy & GraalPy are only supported for manylinux wheels.</sup><br>
 <sup>**2** Windows arm64 support is experimental.</sup><br>
-<sup>**3** Experimental, not yet supported on PyPI, but can be used directly in web deployment. Use `--platform pyodide` to build.</sup><br>
-<sup>**4** manylinux armv7l support is experimental. As there are no RHEL based image for this architecture, it's using an Ubuntu based image instead.</sup><br>
-<sup>**5** Python 3.15 requires opt-in using [`enable`](https://cibuildwheel.pypa.io/en/stable/options/#enable).</sup><br>
+<sup>**3** Not supported on PyPI, uses old `pyodide` tag instead of `pyemscripten`. Requires `pyodide-eol` [`enable`](https://cibuildwheel.pypa.io/en/stable/options/#enable).</sup><br>
+<sup>**4** Experimental alpha ABI, do not upload to PyPI yet.</sup><br>
+<sup>**5** manylinux armv7l support is experimental. As there are no RHEL based image for this architecture, it's using an Ubuntu based image instead.</sup><br>
+<sup>**6** Python 3.15 requires opt-in using [`enable`](https://cibuildwheel.pypa.io/en/stable/options/#enable).</sup><br>
 
-- Builds manylinux, musllinux, macOS, and Windows wheels for CPython, PyPy, and GraalPy
+- Builds manylinux, musllinux, macOS, Windows, pyemscripten, iOS, and Android wheels
+- Supports CPython, PyPy, and GraalPy
 - Works on GitHub Actions, Azure Pipelines, 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)
+- Bundles shared library dependencies on Linux through [auditwheel](https://github.com/pypa/auditwheel), macOS through [delocate](https://github.com/matthew-brett/delocate), and Windows through [delvewheel](https://github.com/adang1345/delvewheel)
 - Runs your library's tests against the wheel-installed version of your library
 
 See the [cibuildwheel 1 documentation](https://cibuildwheel.pypa.io/en/1.x/) if you need to build unsupported versions of Python, such as Python 2.
@@ -98,7 +100,7 @@ jobs:
       - uses: actions/setup-python@v6
 
       - name: Install cibuildwheel
-        run: python -m pip install cibuildwheel==4.0.0rc1
+        run: python -m pip install cibuildwheel==4.0.0rc2
 
       - name: Build wheels
         run: python -m cibuildwheel --output-dir wheelhouse
@@ -150,6 +152,7 @@ The following diagram summarises the steps that cibuildwheel takes on each platf
 |  | [`before-all`](https://cibuildwheel.pypa.io/en/stable/options/#before-all) | Execute a shell command on the build system before any wheels are built. |
 |  | [`before-build`](https://cibuildwheel.pypa.io/en/stable/options/#before-build) | Execute a shell command preparing each wheel's build |
 |  | [`xbuild-tools`](https://cibuildwheel.pypa.io/en/stable/options/#xbuild-tools) | Binaries on the path that should be included in an isolated cross-build environment. |
+|  | [`xbuild-files`](https://cibuildwheel.pypa.io/en/stable/options/#xbuild-files) | Platform-specific files in the build environment |
 |  | [`repair-wheel-command`](https://cibuildwheel.pypa.io/en/stable/options/#repair-wheel-command) | Execute a shell command to repair each built wheel |
 |  | [`manylinux-*-image`<br>`musllinux-*-image`](https://cibuildwheel.pypa.io/en/stable/options/#linux-image) | Specify manylinux / musllinux container images |
 |  | [`container-engine`](https://cibuildwheel.pypa.io/en/stable/options/#container-engine) | Specify the container engine to use when building Linux wheels |
@@ -171,7 +174,7 @@ The following diagram summarises the steps that cibuildwheel takes on each platf
 |  | [`build-verbosity`](https://cibuildwheel.pypa.io/en/stable/options/#build-verbosity) | Increase/decrease the output of the build |
 
 
-<!--[[[end]]] (sum: b7YIjCyCkf) -->
+<!--[[[end]]] (sum: Of/28Z7Nut) -->
 
 These options can be specified in a pyproject.toml file, or as environment variables, see [configuration docs](https://cibuildwheel.pypa.io/en/latest/configuration/).
 
@@ -227,7 +230,7 @@ Here are some repos that use cibuildwheel.
 Legal note
 ----------
 
-Since `cibuildwheel` repairs the wheel with `delocate` or `auditwheel`, it might automatically bundle dynamically linked libraries from the build machine.
+Since `cibuildwheel` repairs the wheel with `delocate`, `auditwheel`, or `delvewheel`, it might automatically bundle dynamically linked libraries from the build machine.
 
 It helps ensure that the library can run without any dependencies outside of the pip toolchain.
 
@@ -238,6 +241,34 @@ Changelog
 
 <!-- [[[cog from readme_changelog import mini_changelog; print(mini_changelog()) ]]] -->
 
+### v4.0.0rc2
+
+_5 June 2026_
+
+- ✨ Adds CPython 3.15 support for iOS and Android (#2857, #2858)
+- ✨ Adds Android improvements for building NumPy and related packages, including auditwheel support, pkg-config and Fortran configuration, and the [`xbuild-files`](https://cibuildwheel.pypa.io/en/stable/options/#xbuild-files) option (#2695)
+- ✨ Adds `CIBUILDWHEEL_BUILD_IDENTIFIER` environment variable set to the current build identifier (e.g. `cp311-manylinux_x86_64`) during per-build steps (#2872)
+- 🔐 Adds SHA256 verification for direct downloads of Python interpreters, virtualenv, and python-build-standalone assets (#2873)
+- 🔐 Adds tarfile extraction filter for safe archive extraction (#2856)
+- 🐛 Fixes detection of musl libc when downloading python-build-standalone, which previously always selected the gnu asset on musl hosts like Alpine (#2889)
+- 🐛 Fixes [`config-settings`](https://cibuildwheel.pypa.io/en/stable/options/#config-settings) expansion when `{project}` or `{package}` contains spaces or backslashes (#2886)
+- 🐛 Prevents deadlock when `linux32` fails and forwards platform args to the sanity check (#2880, #2888)
+- 🐛 Fixes container resource leaks on start failure and during teardown (#2879, #2887)
+- 🐛 Removes potential partial cache-population in case of error (#2892)
+- 🐛 Raises a clear error when `ANDROID_API_LEVEL` is not an integer (#2891)
+- 🐛 Replaces assert with proper exception in python-build-standalone (#2859)
+- 🛠 Updates dependencies and container pins (#2893, #2882, #2874, #2868, #2862, #2884)
+- 🛠 Minor fixups across error messages, OCI container, and options (#2860)
+- 📚 Updates documentation for delvewheel as the default Windows [`repair-wheel-command`](https://cibuildwheel.pypa.io/en/stable/options/#repair-wheel-command), including the build diagram, schema defaults, and legal note (#2877, #2853, #2891)
+- 📚 Adds intersphinx support for external documentation linking (#2871)
+- 📚 Removes outdated numpy info (#2855)
+- 💼 Improves Azure test reliability with retries and caching (#2890)
+- 💼 Fixes Windows GitLab CI test running (#2870)
+- 💼 Updates CI action pins (#2867)
+- 💼 Adds agent and copilot setup files (#2861)
+- 💼 Uses `if TYPE_CHECKING:` blocks (#2866, #2864)
+- 🧪 Adds unit tests for `OCIContainer._get_platform_args` (#2878)
+
 ### v4.0.0rc1
 
 _14 May 2026_
@@ -295,21 +326,7 @@ _5 January 2026_
 
 - 🛠 Update dependencies and container pins, including updating to CPython 3.14.2. (#2708)
 
-### v3.3.0
-
-_12 November 2025_
-
-- 🐛 Fix an incompatibility with Docker v29 (#2660)
-- ✨ Adds `test-runtime` option, to customise how tests on simulated/emulated environments are run (#2636)
-- ✨ Adds support for new `manylinux_2_35` images on 32-bit ARM `armv7l`, offering better C++20 compatibility (#2656)
-- ✨ `build[uv]` is now supported on Android (#2587)
-- ✨ You can now install extras (such as `uv`) with a simple option on the GitHub Action (#2630)
-- ✨ `{project}` and `{package}` placeholders are now supported in `repair-wheel-command` (#2589)
-- 🛠 The versions set with `dependency-versions` no longer constrain packages specified by your `build-system.requires`. Previously, on platforms other than Linux, the constraints in this option would remain in the environment during the build. This has been tidied up make behaviour more consistent between platforms, and to prevent version conflicts. (#2583)
-- 🛠 Improve the handling of `test-command` on Android, enabling more options to be passed (#2590)
-- 📚 Docs improvements (#2618)
-
-<!-- [[[end]]] (sum: ZD0EjcyC0B) -->
+<!-- [[[end]]] (sum: x/zQO1S1XP) -->
 
 ---
 

azure-pipelines.yml

@@ -19,39 +19,54 @@ jobs:
 - job: tests
   strategy:
     matrix:
-      linux_311:
+      linux_313:
         imageName: "ubuntu-latest"
-        pythonVersion: "3.11"
+        pythonVersion: "3.13"
         testSelect: "native"
-      android_311:
+      android_313:
         imageName: "ubuntu-latest"
-        pythonVersion: "3.11"
+        pythonVersion: "3.13"
         testSelect: "android"
-      macos_311:
+      macos_313:
         imageName: "macos-latest"
-        pythonVersion: "3.11"
+        pythonVersion: "3.13"
         testSelect: "native"
-      ios_311:
+      ios_313:
         imageName: "macos-14"  # See https://github.com/actions/runner-images/issues/12777
-        pythonVersion: "3.11"
+        pythonVersion: "3.13"
         testSelect: "ios"
-      android_macos_311:
+      android_macos_313:
         imageName: "macos-latest"
-        pythonVersion: "3.11"
+        pythonVersion: "3.13"
         testSelect: "android"
-      windows_311:
+      windows_313:
         imageName: "windows-latest"
-        pythonVersion: "3.11"
+        pythonVersion: "3.13"
         testSelect: "native"
   timeoutInMinutes: 180
   pool:
     vmImage: $(imageName)
+  variables:
+    # Relocate cibuildwheel's download cache (interpreters) and the per-worker
+    # test pip caches (which live under it) to a stable, cacheable path.
+    CIBW_CACHE_PATH: $(Pipeline.Workspace)/.cibw-cache
 
   steps:
     - task: UsePythonVersion@0
       inputs:
         versionSpec: $(pythonVersion)
 
+    - task: Cache@2
+      displayName: 'Cache cibuildwheel downloads'
+      inputs:
+        # build-platforms.toml carries the interpreter pins; bump the version
+        # prefix to force a cold cache. restoreKeys lets a stale cache still seed
+        # a new run (cibuildwheel re-downloads only what's missing).
+        key: 'cibw-cache | v1 | "$(imageName)" | "$(testSelect)" | cibuildwheel/resources/build-platforms.toml'
+        restoreKeys: |
+          cibw-cache | v1 | "$(imageName)" | "$(testSelect)"
+        path: $(CIBW_CACHE_PATH)
+
     - task: JavaToolInstaller@0
       condition: and(eq(variables['testSelect'], 'android'), eq(variables['Agent.OS'], 'Linux'))
       inputs:

bin/generate_schema.py

@@ -15,6 +15,8 @@ parser = argparse.ArgumentParser(allow_abbrev=False)
 parser.add_argument("--schemastore", action="store_true", help="Generate schema_store version")
 args = parser.parse_args()
 
+# The defaults in the schema are used by external tools for validation and IDE support. They
+# should match the values in defaults.toml, which are used by cibuildwheel itself.
 starter = """
 $schema: http://json-schema.org/draft-07/schema#
 $id: https://github.com/pypa/cibuildwheel/blob/main/cibuildwheel/resources/cibuildwheel.schema.json
@@ -200,6 +202,9 @@ properties:
   xbuild-tools:
     description: Binaries on the path that should be included in an isolated cross-build environment
     type: string_array
+  xbuild-files:
+    description: Platform-specific files in the build environment
+    type: string_table_array
   pyodide-version:
     type: string
     description: Specify the version of Pyodide to use
@@ -319,6 +324,7 @@ items:
         before-all: {"$ref": "#/$defs/inherit"}
         before-build: {"$ref": "#/$defs/inherit"}
         xbuild-tools: {"$ref": "#/$defs/inherit"}
+        xbuild-files: {"$ref": "#/$defs/inherit"}
         before-test: {"$ref": "#/$defs/inherit"}
         config-settings: {"$ref": "#/$defs/inherit"}
         container-engine: {"$ref": "#/$defs/inherit"}
@@ -374,14 +380,16 @@ oses = {
     "ios": as_object(not_linux),
 }
 
-oses["linux"]["properties"]["repair-wheel-command"] = {
-    **schema["properties"]["repair-wheel-command"],
-    "default": "auditwheel repair -w {dest_dir} {wheel}",
-}
-oses["macos"]["properties"]["repair-wheel-command"] = {
-    **schema["properties"]["repair-wheel-command"],
-    "default": "delocate-wheel --require-archs {delocate_archs} -w {dest_dir} -v {wheel}",
-}
+for os_name, command in [
+    ("linux", "auditwheel repair -w {dest_dir} {wheel}"),
+    ("windows", "delvewheel repair -w {dest_dir} -v {wheel}"),
+    ("macos", "delocate-wheel --require-archs {delocate_archs} -w {dest_dir} -v {wheel}"),
+    ("android", "auditwheel repair --ldpaths {ldpaths} -w {dest_dir} {wheel}"),
+]:
+    oses[os_name]["properties"]["repair-wheel-command"] = {
+        **schema["properties"]["repair-wheel-command"],
+        "default": command,
+    }
 
 del oses["linux"]["properties"]["dependency-versions"]
 

bin/inspect_all_known_projects.py

@@ -24,8 +24,9 @@ This will cache the results to all_known_setup.yaml; you can reprint
 the results without the `--online` setting.
 """
 
+from __future__ import annotations
+
 import ast
-from collections.abc import Iterable, Iterator
 from pathlib import Path
 
 import click
@@ -35,6 +36,10 @@ from rich import print
 
 from cibuildwheel.projectfiles import Analyzer
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Iterable, Iterator
+
 DIR = Path(__file__).parent.resolve()
 
 

bin/projects.py

@@ -17,13 +17,14 @@ Suggested usage:
     git diff
 """
 
+from __future__ import annotations
+
 import builtins
 import functools
 import textwrap
 import urllib.error
 import urllib.request
 import xml.dom.minidom
-from collections.abc import Iterable, Mapping, Sequence
 from datetime import UTC, datetime
 from io import StringIO
 from pathlib import Path
@@ -33,6 +34,10 @@ import click
 import yaml
 from github import Auth, Github, GithubException
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Iterable, Mapping, Sequence
+
 ICONS = (
     "github",
     "azurepipelines",

bin/run_example_ci_configs.py

@@ -3,6 +3,7 @@
 # /// script
 # dependencies = [
 #   "click",
+#   "jinja2",
 # ]
 # ///
 
@@ -39,13 +40,16 @@ def generate_project(path: Path, build_backend: BuildBackend) -> None:
     sys.path.insert(0, "")
     match build_backend:
         case "meson":
-            from test.test_projects.meson import new_meson_project as new_project  # noqa: PLC0415
+            from test.test_projects.meson import new_meson_project  # noqa: PLC0415
+
+            project = new_meson_project()
         case "setuptools":
-            from test.test_projects.setuptools import new_c_project as new_project  # noqa: PLC0415
+            from test.test_projects.setuptools import new_c_project  # noqa: PLC0415
+
+            project = new_c_project()
         case _:
             typing.assert_never(build_backend)
 
-    project = new_project()
     project.generate(path)
 
 

bin/update_python_build_standalone.py

@@ -3,6 +3,7 @@
 # /// script
 # dependencies = [
 #   "cibuildwheel",
+#   "requests",
 # ]
 #
 # [tool.uv.sources]
@@ -10,13 +11,23 @@
 # ///
 
 import json
+from pathlib import Path
+from typing import Final
+
+import requests
 
 from cibuildwheel.extra import github_api_request
 from cibuildwheel.util.python_build_standalone import (
     PythonBuildStandaloneAsset,
     PythonBuildStandaloneReleaseData,
 )
-from cibuildwheel.util.resources import PYTHON_BUILD_STANDALONE_RELEASES
+
+# Resolve path relative to this script so writes go to the source checkout,
+# not the uv-installed copy of the package.
+DIR: Final[Path] = Path(__file__).parent.parent.resolve()
+PYTHON_BUILD_STANDALONE_RELEASES: Final[Path] = (
+    DIR / "cibuildwheel/resources/python-build-standalone-releases.json"
+)
 
 
 def main() -> None:
@@ -34,8 +45,27 @@ def main() -> None:
         f"repos/astral-sh/python-build-standalone/releases/tags/{latest_tag}"
     )["assets"]
 
+    # Build a sha256 map from the SHA256SUMS file in the release
+    sha256_sums_urls = [
+        ga["browser_download_url"] for ga in github_assets if ga["name"] == "SHA256SUMS"
+    ]
+    name_to_sha256: dict[str, str] = {}
+    if sha256_sums_urls:
+        response = requests.get(sha256_sums_urls[0])
+        response.raise_for_status()
+        for line in response.text.splitlines():
+            parts = line.split()
+            if len(parts) == 2:
+                sha256_hex, filename = parts
+                # The filename may have a leading "./" or spaces - strip it
+                name_to_sha256[filename.lstrip("./")] = sha256_hex
+
     assets = [
-        PythonBuildStandaloneAsset(name=ga["name"], url=ga["browser_download_url"])
+        PythonBuildStandaloneAsset(
+            name=ga["name"],
+            url=ga["browser_download_url"],
+            sha256=name_to_sha256.get(ga["name"], ""),
+        )
         for ga in github_assets
         if ga["name"].endswith("install_only.tar.gz")
     ]

bin/update_pythons.py

@@ -12,16 +12,16 @@
 # [tool.uv.sources]
 # cibuildwheel = { path = ".." }
 # ///
-
+from __future__ import annotations
 
 import difflib
+import hashlib
 import logging
 import operator
 import re
 import tomllib
-from collections.abc import Mapping, MutableMapping
 from pathlib import Path
-from typing import Any, Final, Literal, TypedDict
+from typing import Any, Final, Literal, NotRequired, TypedDict
 from xml.etree import ElementTree as ET
 
 import click
@@ -35,6 +35,10 @@ from rich.syntax import Syntax
 from cibuildwheel.extra import dump_python_configurations, get_pyodide_xbuildenv_info
 from cibuildwheel.platforms.android import android_triplet
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Mapping, MutableMapping
+
 log = logging.getLogger("cibw")
 
 # Looking up the dir instead of using utils.resources_dir
@@ -53,11 +57,13 @@ class Config(TypedDict):
 
 class ConfigUrl(Config):
     url: str
+    sha256: NotRequired[str]
 
 
 class ConfigPyodide(Config):
     default_pyodide_version: str
     node_version: str
+    sha256: str
 
 
 # The following set of "Versions" classes allow the initial call to the APIs to
@@ -152,10 +158,6 @@ class GraalPyVersions:
             msg = f"GraalPy {arch} not found for {spec}!"
             raise RuntimeError(msg)
 
-        release = releases[-1]
-        version = release["python_version"]
-        gpversion = release["graalpy_version"]
-
         if "macosx" in identifier:
             arch = "x86_64" if "x86_64" in identifier else "arm64"
             platform = "macos"
@@ -168,19 +170,38 @@ class GraalPyVersions:
 
         arch = "amd64" if arch == "x86_64" else "aarch64"
         ext = "zip" if "win" in identifier else "tar.gz"
-        urls = [
-            rf["browser_download_url"]
-            for rf in release["assets"]
-            if rf["name"].endswith(f"{platform}-{arch}.{ext}")
-            and rf["name"].startswith(f"graalpy-{gpversion.major}")
-        ]
-        if urls:
+        for release in reversed(releases):
+            version = release["python_version"]
+            gpversion = release["graalpy_version"]
+            urls = [
+                rf["browser_download_url"]
+                for rf in release["assets"]
+                if rf["name"].endswith(f"{platform}-{arch}.{ext}")
+                and rf["name"].startswith(f"graalpy-{gpversion.major}")
+            ]
+            if not urls:
+                continue
+
             (url,) = urls
+            # Fetch sha256 from the ".sha256" sidecar asset in the same release.
+            sha256 = ""
+            sha256_asset_name = url.rsplit("/", 1)[-1] + ".sha256"
+            sha256_urls = [
+                rf["browser_download_url"]
+                for rf in release["assets"]
+                if rf["name"] == sha256_asset_name
+            ]
+            if sha256_urls:
+                sha256_response = requests.get(sha256_urls[0])
+                sha256_response.raise_for_status()
+                sha256 = sha256_response.text.strip().split()[0]
             return ConfigUrl(
                 identifier=identifier,
                 version=f"{version.major}.{version.minor}",
                 url=url,
+                sha256=sha256,
             )
+
         return None
 
 
@@ -295,12 +316,14 @@ class CPythonVersions:
             uri = self.versions_dict[new_version]
             files = [rf for rf in self.files_info if rf["release"] == uri]
 
-            urls = [rf["url"] for rf in files if file_ident in rf["url"]]
-            if urls:
+            matching = [rf for rf in files if file_ident in rf["url"]]
+            if matching:
+                rf = matching[0]
                 return ConfigUrl(
                     identifier=identifier,
                     version=f"{new_version.major}.{new_version.minor}",
-                    url=urls[0],
+                    url=rf["url"],
+                    sha256=rf.get("sha256_sum", ""),
                 )
 
         return None
@@ -417,6 +440,7 @@ class PyodideVersions:
             version=str(version),
             default_pyodide_version=release["version"],
             node_version=node_version,
+            sha256=release["sha256"],
         )
 
 
@@ -445,6 +469,16 @@ class AllVersions:
 
         self.pyodide = PyodideVersions()
 
+    def _stream_sha256(self, url: str) -> str:
+        """Download a file (streaming) and return its SHA256 hex digest."""
+        log.debug("Computing sha256 for %s by streaming download...", url)
+        response = requests.get(url, stream=True)
+        response.raise_for_status()
+        hasher = hashlib.sha256()
+        for chunk in response.iter_content(65536):
+            hasher.update(chunk)
+        return hasher.hexdigest()
+
     def update_config(self, config: MutableMapping[str, str]) -> None:
         identifier = config["identifier"]
         version = Version(config["version"])
@@ -462,8 +496,6 @@ class AllVersions:
                 elif "macosx_arm64" in identifier:
                     config_update = self.macos_pypy_arm64.update_version_macos(spec)
             elif identifier.startswith("gp"):
-                if "macosx_x86_64" in identifier:
-                    return
                 config_update = self.graalpy.update_version(identifier, spec)
         elif "t-win32" in identifier and identifier.startswith("cp"):
             config_update = self.windows_t_32.update_version_windows(spec)
@@ -488,13 +520,36 @@ class AllVersions:
             versions = self.maven if identifier.startswith("cp313") else self.cpython
             config_update = versions.update_version_android(identifier, spec)
         elif "ios" in identifier:
-            config_update = self.ios_cpython.update_version_ios(identifier, version)
+            # Python 3.13 and 3.14 are released by BeeWare on GitHub.
+            # Python 3.15 and newer have official releases on python.org.
+            if identifier.startswith(("cp313", "cp314")):
+                config_update = self.ios_cpython.update_version_ios(identifier, version)
+            else:
+                config_update = self.cpython.update_version(
+                    identifier, spec, "iOS-XCframework.tar.gz"
+                )
         elif "pyodide" in identifier:
             config_update = self.pyodide.update_version_pyodide(
                 identifier, version, spec, config["node_version"]
             )
 
         assert config_update is not None, f"{identifier} not found!"
+
+        # Fill in sha256 for URL-based configs if not already provided by the
+        # update_version_* method (e.g. PyPy, BeeWare iOS, Maven have no sidecar).
+        # Also fills in sha256 when the CPython API doesn't return a sha256_sum
+        # (e.g. for older releases).
+        # Widen the type to allow arbitrary key access on the underlying dict.
+        config_update_dict: dict[str, str] = config_update  # type: ignore[assignment]
+        if "url" in config_update_dict and not config_update_dict.get("sha256"):
+            url = config_update_dict["url"]
+            existing_sha256 = config.get("sha256", "")
+            if url == config.get("url") and existing_sha256:
+                # URL unchanged — preserve the existing sha256
+                config_update_dict["sha256"] = existing_sha256
+            else:
+                config_update_dict["sha256"] = self._stream_sha256(url)
+
         if config_update != config:
             log.info("  Updated %s to %s", config, config_update)
             config.clear()

bin/update_virtualenv.py

@@ -4,6 +4,7 @@
 # dependencies = [
 #   "click",
 #   "packaging",
+#   "requests",
 #   "rich",
 #   "cibuildwheel",
 # ]
@@ -15,12 +16,14 @@
 
 import dataclasses
 import difflib
+import hashlib
 import logging
 import tomllib
 from pathlib import Path
 from typing import Final
 
 import click
+import requests
 import rich
 from packaging.version import Version
 from rich.logging import RichHandler
@@ -92,16 +95,29 @@ def update_virtualenv(force: bool, level: str) -> None:
     if latest_release.version > Version(local_version):
         version = latest_release.name
         url = latest_release.download_url
+        sha256 = ""  # recomputed below
     else:
         version = local_version
         url = default["url"]
+        sha256 = default["sha256"]
+
+    # Compute sha256 if not already stored (new version or first-time population)
+    if not sha256:
+        log.info("Computing sha256 for %s...", url)
+        response = requests.get(url, stream=True)
+        response.raise_for_status()
+        hasher = hashlib.sha256()
+        for chunk in response.iter_content(65536):
+            hasher.update(chunk)
+        sha256 = hasher.hexdigest()
 
     configurations["default"] = {
         "version": version,
         "url": url,
+        "sha256": sha256,
     }
     result_toml = "".join(
-        f'{key} = {{ version = "{value["version"]}", url = "{value["url"]}" }}\n'
+        f'{key} = {{ version = "{value["version"]}", url = "{value["url"]}", sha256 = "{value["sha256"]}" }}\n'
         for key, value in configurations.items()
     )
 

cibuildwheel/__init__.py

@@ -1 +1 @@
-__version__ = "4.0.0rc1"
+__version__ = "4.0.0rc2"

cibuildwheel/__main__.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import argparse
 import contextlib
 import dataclasses
@@ -5,17 +7,15 @@ import functools
 import os
 import shutil
 import sys
-import tarfile
 import textwrap
 import traceback
 import typing
-from collections.abc import Generator, Iterable, Sequence
 from pathlib import Path
 from tempfile import mkdtemp
-from typing import Any, Literal, TextIO
 
 import cibuildwheel
 from cibuildwheel import errors
+from cibuildwheel._compat.tarfile import TarFile, safe_extractall
 from cibuildwheel.architecture import Architecture, allowed_architectures_check
 from cibuildwheel.ci import CIProvider, detect_ci_provider, fix_ansi_codes_for_github_actions
 from cibuildwheel.logger import log
@@ -27,6 +27,11 @@ from cibuildwheel.util.file import CIBW_CACHE_PATH, ensure_cache_sentinel
 from cibuildwheel.util.helpers import strtobool
 from cibuildwheel.util.resources import read_all_configs
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Generator, Iterable, Sequence
+    from typing import Any, Literal, TextIO
+
 
 @dataclasses.dataclass
 class GlobalOptions:
@@ -262,8 +267,8 @@ def main_inner(global_options: GlobalOptions) -> None:
     # Tarfile builds require extraction and changing the directory
     temp_dir = Path(mkdtemp(prefix="cibw-sdist-")).resolve(strict=True)
     try:
-        with tarfile.open(args.package_dir) as tar:
-            tar.extractall(path=temp_dir)
+        with TarFile.open(args.package_dir) as tar:
+            safe_extractall(tar, temp_dir)
 
         # The extract directory is now the project dir
         try:

cibuildwheel/_compat/tarfile.py

@@ -0,0 +1,71 @@
+# Based on https://github.com/pypa/build/blob/f4ebd495cc0c2c74155bd4fe48b76399fb7927ac/src/build/_compat/tarfile.py
+
+from __future__ import annotations
+
+import sys
+import tarfile
+
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from pathlib import Path
+
+    TarFile = tarfile.TarFile
+
+# Per https://peps.python.org/pep-0706/, the "data" filter will become
+# the default in Python 3.14. The first series of releases with the filter
+# had a broken filter that could not process symlinks correctly.
+elif (3, 11, 5) <= sys.version_info < (3, 14):
+
+    class TarFile(tarfile.TarFile):  # pragma: no cover
+        extraction_filter = staticmethod(tarfile.data_filter)
+
+else:
+    TarFile = tarfile.TarFile  # pragma: no cover
+
+
+# Same availability matrix as the TarFile subclass above. On runtimes that
+# ship the stdlib ``data`` filter we delegate to it; the fallback branch is
+# only reached on 3.10.0-3.10.12 / 3.11.0-3.11.4 and validates each member
+# manually before extraction.
+if sys.version_info >= (3, 11, 5):
+
+    def safe_extractall(tar: tarfile.TarFile, path: Path) -> None:  # pragma: no cover
+        """Extract every member of ``tar`` into ``path`` via the PEP 706 ``data`` filter."""
+        tar.extractall(path, filter="data")
+
+else:
+
+    def safe_extractall(tar: tarfile.TarFile, path: Path) -> None:  # pragma: no cover
+        """Validate every member of ``tar``, then extract into ``path``.
+
+        Reached on 3.10.0-3.10.12 / 3.11.0-3.11.4 where the stdlib ``data`` filter is missing. Device or special files,
+        paths that escape ``path``, and symlinks/hardlinks whose targets resolve outside ``path`` are rejected before
+        any write hits the disk.
+
+        """
+        base = path.resolve()
+        for member in tar.getmembers():
+            _validate_safe_member(member, base)
+        tar.extractall(path)
+
+
+def _validate_safe_member(member: tarfile.TarInfo, base: Path) -> None:
+    if member.ischr() or member.isblk() or member.isfifo():
+        msg = f"refusing to extract special device file {member.name!r}"
+        raise tarfile.TarError(msg)
+    target = (base / member.name).resolve(strict=False)
+    if not target.is_relative_to(base):
+        msg = f"refusing to extract {member.name!r}: path escapes destination"
+        raise tarfile.TarError(msg)
+    if member.issym() or member.islnk():
+        link_base = target.parent if member.issym() else base
+        link_target = (link_base / member.linkname).resolve(strict=False)
+        if not link_target.is_relative_to(base):
+            msg = f"refusing to extract {member.name!r}: link target escapes destination"
+            raise tarfile.TarError(msg)
+
+
+__all__ = [
+    "TarFile",
+    "safe_extractall",
+]

cibuildwheel/architecture.py

@@ -1,15 +1,21 @@
+from __future__ import annotations
+
 import platform as platform_module
 import re
 import shutil
 import subprocess
 import sys
 import typing
-from collections.abc import Set
 from enum import StrEnum, auto
-from typing import Final, Literal, Self
 
 from cibuildwheel import errors
-from cibuildwheel.typing import PlatformName
+
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Set
+    from typing import Final, Literal, Self
+
+    from cibuildwheel.typing import PlatformName
 
 PRETTY_NAMES: Final[dict[PlatformName, str]] = {
     "linux": "Linux",

cibuildwheel/audit.py

@@ -1,15 +1,20 @@
+from __future__ import annotations
+
 import subprocess
 import sys
 from pathlib import Path
 
 from cibuildwheel import errors
 from cibuildwheel.logger import log
-from cibuildwheel.options import BuildOptions
 from cibuildwheel.util.cmd import call, shell
 from cibuildwheel.util.helpers import prepare_command
 from cibuildwheel.util.packaging import is_abi3_wheel
 from cibuildwheel.venv import activate_virtualenv, find_uv, virtualenv
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from cibuildwheel.options import BuildOptions
+
 
 def run_audit(
     *,

cibuildwheel/bashlex_eval.py

@@ -1,16 +1,21 @@
+from __future__ import annotations
+
 import dataclasses
 import subprocess
-from collections.abc import (
-    Callable,
-    Iterable,
-    Mapping,
-    Sequence,
-)
 
 import bashlex
 
-# a function that takes a command and the environment, and returns the result
-EnvironmentExecutor = Callable[[list[str], dict[str, str]], str]
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import (
+        Callable,
+        Iterable,
+        Mapping,
+        Sequence,
+    )
+
+    # a function that takes a command and the environment, and returns the result
+    EnvironmentExecutor = Callable[[list[str], dict[str, str]], str]
 
 
 def local_environment_executor(command: Sequence[str], env: Mapping[str, str]) -> str:

cibuildwheel/environment.py

@@ -1,12 +1,18 @@
+from __future__ import annotations
+
 import dataclasses
-from collections.abc import Mapping, Sequence
-from typing import Any, Protocol
+from typing import Protocol
 
 import bashlex
 import bashlex.errors
 
 from cibuildwheel import bashlex_eval
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Mapping, Sequence
+    from typing import Any
+
 
 class EnvironmentParseError(Exception):
     pass

cibuildwheel/errors.py

@@ -76,7 +76,7 @@ class RepairStepProducedNoWheelError(FatalError):
             Build failed because the repair step completed successfully but
             did not produce a wheel.
 
-            Your `repair-wheel-command` is expected to place the repaired
+            Your `repair-wheel-command` must place the repaired
             wheel in the {dest_dir} directory. See the documentation for
             example configurations:
 
@@ -94,7 +94,7 @@ class RepairStepProducedMultipleWheelsError(FatalError):
             Build failed because the repair step completed successfully but
             produced multiple wheels: {wheels}
 
-            Your `repair-wheel-command` is expected to place one repaired
+            Your `repair-wheel-command` must place exactly one repaired
             wheel in the {{dest_dir}} directory. See the documentation for
             example configurations:
 

cibuildwheel/extra.py

@@ -2,17 +2,24 @@
 These are utilities for the `/bin` scripts, not for the `cibuildwheel` program.
 """
 
+from __future__ import annotations
+
 import json
 import time
 import typing
 import urllib.error
 import urllib.request
-from collections.abc import Mapping, Sequence
 from io import StringIO
-from typing import Any, NotRequired, Protocol
+from typing import NotRequired, Protocol
 
 from cibuildwheel import __version__ as cibw_version
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Mapping, Sequence
+    from typing import Any
+
+
 __all__ = ("Printable", "dump_python_configurations")
 
 
@@ -83,6 +90,7 @@ def github_api_request(path: str, *, max_retries: int = 3) -> dict[str, Any]:
 
 class PyodideXBuildEnvRelease(typing.TypedDict):
     version: str
+    sha256: str
     python_version: str
     emscripten_version: str
     min_pyodide_build_version: NotRequired[str]

cibuildwheel/frontend.py

@@ -1,12 +1,19 @@
+from __future__ import annotations
+
 import dataclasses
 import shlex
 import typing
-from collections.abc import Sequence
-from typing import Literal, Self, get_args
+from typing import Literal, get_args
 
-from cibuildwheel.typing import PathOrStr
 from cibuildwheel.util.helpers import parse_key_value_string, prepare_command
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Sequence
+    from typing import Self
+
+    from cibuildwheel.typing import PathOrStr
+
 BuildFrontendName = Literal["pip", "build", "build[uv]", "uv"]
 
 
@@ -55,7 +62,17 @@ def _split_config_settings(config_settings: str) -> list[str]:
 
 
 def prepare_config_settings(config_settings: str, *, project: PathOrStr, package: PathOrStr) -> str:
-    return prepare_command(config_settings, project=project, package=package)
+    # Substitute the {project}/{package} placeholders on each already-split
+    # token rather than on the raw string. A substituted path may contain
+    # spaces or backslashes (e.g. a Windows `{package}` path), and the result
+    # is later re-parsed with shlex.split (in _split_config_settings /
+    # parse_config_settings) — substituting on the whole string would let
+    # those characters be reinterpreted, splitting one setting into several or
+    # eating backslashes. shlex.join re-quotes each token so the round-trip is
+    # lossless.
+    settings = shlex.split(config_settings)
+    prepared = [prepare_command(setting, project=project, package=package) for setting in settings]
+    return shlex.join(prepared)
 
 
 # Based on build.__main__.main.

cibuildwheel/logger.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import codecs
 import contextlib
 import dataclasses
@@ -9,18 +11,21 @@ import re
 import sys
 import textwrap
 import time
-from collections.abc import Generator
 from pathlib import Path
-from typing import IO, TYPE_CHECKING, AnyStr, Final, Literal
 
 import humanize
 
 from cibuildwheel.ci import CIProvider, detect_ci_provider, filter_ansi_codes
 
+TYPE_CHECKING = False
 if TYPE_CHECKING:
+    from collections.abc import Generator
+    from typing import IO, AnyStr, Final, Literal
+
     from cibuildwheel.options import Options
 
-FoldPattern = tuple[str, str]
+    FoldPattern = tuple[str, str]
+
 DEFAULT_FOLD_PATTERN: Final[FoldPattern] = ("{name}", "")
 FOLD_PATTERNS: Final[dict[str, FoldPattern]] = {
     "azure": ("##[group]{name}", "##[endgroup]"),
@@ -234,7 +239,7 @@ class Logger:
             print(f"cibuildwheel: {c.bright_red}error{c.end}: {error}\n", file=sys.stderr)
 
     @contextlib.contextmanager
-    def print_summary(self, *, options: "Options") -> Generator[None, None, None]:
+    def print_summary(self, *, options: Options) -> Generator[None, None, None]:
         start = time.time()
         yield
         duration = time.time() - start
@@ -292,7 +297,7 @@ class Logger:
         # lowercase, shorten
         return identifier.lower()[:20]
 
-    def _github_step_summary(self, duration: float, options: "Options") -> str:
+    def _github_step_summary(self, duration: float, options: Options) -> str:
         """
         Returns the GitHub step summary, in markdown format.
         """

cibuildwheel/oci_container.py

@@ -1,3 +1,6 @@
+from __future__ import annotations
+
+import contextlib
 import dataclasses
 import io
 import json
@@ -10,19 +13,25 @@ import sys
 import textwrap
 import typing
 import uuid
-from collections.abc import Mapping, Sequence
 from enum import Enum
-from pathlib import Path, PurePath, PurePosixPath
-from types import TracebackType
-from typing import IO, Literal, Self, assert_never
+from pathlib import PurePosixPath
+from typing import Literal, assert_never
 
 from cibuildwheel.ci import CIProvider, detect_ci_provider
 from cibuildwheel.errors import OCIEngineTooOldError
 from cibuildwheel.logger import log
-from cibuildwheel.typing import PathOrStr
 from cibuildwheel.util.cmd import call
 from cibuildwheel.util.helpers import FlexibleVersion, parse_key_value_string, strtobool
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Mapping, Sequence
+    from pathlib import Path, PurePath
+    from types import TracebackType
+    from typing import IO, Self
+
+    from cibuildwheel.typing import PathOrStr
+
 ContainerEngineName = Literal["docker", "podman"]
 
 
@@ -198,7 +207,6 @@ class OCIContainer:
 
     UTILITY_PYTHON = "/opt/python/cp39-cp39/bin/python"
 
-    process: subprocess.Popen[bytes]
     bash_stdin: IO[bytes]
     bash_stdout: IO[bytes]
 
@@ -218,6 +226,7 @@ class OCIContainer:
         self.oci_platform = oci_platform
         self.cwd = cwd
         self.name: str | None = None
+        self.process: subprocess.Popen[bytes] | None = None
         self.engine = engine
         self.host_tar_format = ""
         if sys.platform.startswith("darwin"):
@@ -249,10 +258,12 @@ class OCIContainer:
                 # this allows to run local only images
                 pull = "never"
         except subprocess.CalledProcessError:
+            # silently fallback to "--pull=always"
             pass
         return f"--platform={oci_platform.value}", f"--pull={pull}"
 
     def __enter__(self) -> Self:
+        assert self.process is None
         self.name = f"cibuildwheel-{uuid.uuid4()}"
 
         _check_engine_version(self.engine)
@@ -288,7 +299,17 @@ class OCIContainer:
                     ).strip()
                 else:
                     raise
-            simulate_32_bit = container_machine not in {"i686", "armv7l", "armv8l"}
+            if container_machine not in {"i686", "armv7l", "armv8l"}:
+                simulate_32_bit = True
+                # sanity check to ensure no deadlock waiting for container to start
+                call(
+                    *run_cmd,
+                    *platform_args,
+                    self.image,
+                    "linux32",
+                    "/bin/true",
+                    capture_stdout=True,
+                )
 
         shell_args = ["linux32", "/bin/bash"] if simulate_32_bit else ["/bin/bash"]
 
@@ -310,32 +331,41 @@ class OCIContainer:
             check=True,
         )
 
-        self.process = subprocess.Popen(
-            [
-                self.engine.name,
-                "start",
-                "--attach",
-                "--interactive",
-                self.name,
-            ],
-            stdin=subprocess.PIPE,
-            stdout=subprocess.PIPE,
-        )
+        try:
+            self.process = subprocess.Popen(
+                [
+                    self.engine.name,
+                    "start",
+                    "--attach",
+                    "--interactive",
+                    self.name,
+                ],
+                stdin=subprocess.PIPE,
+                stdout=subprocess.PIPE,
+            )
 
-        assert self.process.stdin
-        assert self.process.stdout
-        self.bash_stdin = self.process.stdin
-        self.bash_stdout = self.process.stdout
+            assert self.process.stdin
+            assert self.process.stdout
+            self.bash_stdin = self.process.stdin
+            self.bash_stdout = self.process.stdout
 
-        # run a noop command to block until the container is responding
-        self.call(["/bin/true"], cwd="/")
-
-        if self.cwd:
-            # Although `docker create -w` does create the working dir if it
-            # does not exist, podman does not. There does not seem to be a way
-            # to setup a workdir for a container running in podman.
-            self.call(["mkdir", "-p", os.fspath(self.cwd)], cwd="/")
+            # run a noop command to block until the container is responding
+            self.call(["/bin/true"], cwd="/")
 
+            if self.cwd:
+                # Although `docker create -w` does create the working dir if it
+                # does not exist, podman does not. There does not seem to be a way
+                # to setup a workdir for a container running in podman.
+                self.call(["mkdir", "-p", os.fspath(self.cwd)], cwd="/")
+        except BaseException:
+            # clean-up
+            if self.process is not None:
+                if self.process.poll() is None:
+                    self.process.kill()
+                self.process.communicate()
+            self.process = None
+            self._remove_container()
+            raise
         return self
 
     def __exit__(
@@ -344,29 +374,52 @@ class OCIContainer:
         exc_val: BaseException | None,
         exc_tb: TracebackType | None,
     ) -> None:
-        self.bash_stdin.write(b"exit 0\n")
-        self.bash_stdin.flush()
-        self.process.wait(timeout=30)
-        self.bash_stdin.close()
-        self.bash_stdout.close()
+        assert self.process is not None
+        try:
+            # Ask bash to exit cleanly and wait for the `start` process to finish.
+            # If the container/bash has already died, the write raises
+            # BrokenPipeError; if bash refuses to exit, `wait` raises
+            # TimeoutExpired. Both are handled below so we always reach the
+            # cleanup in `finally` rather than leaking the process or container.
+            self.bash_stdin.write(b"exit 0\n")
+            self.bash_stdin.flush()
+            self.process.wait(timeout=30)
 
-        if self.engine.name == "podman":
-            # This works around what seems to be a race condition in the podman
-            # backend. The full reason is not understood. See PR #966 for a
-            # discussion on possible causes and attempts to remove this line.
-            # For now, this seems to work "well enough".
-            self.process.wait()
+            if self.engine.name == "podman":
+                # This works around what seems to be a race condition in the
+                # podman backend. The full reason is not understood. See PR #966
+                # for a discussion on possible causes and attempts to remove this
+                # line. For now, this seems to work "well enough".
+                self.process.wait()
+        except (OSError, subprocess.TimeoutExpired):
+            # bash didn't shut down cleanly; force the process down so it isn't
+            # leaked, then continue to cleanup.
+            if self.process.poll() is None:
+                self.process.kill()
+                self.process.wait()
+        finally:
+            with contextlib.suppress(OSError):
+                self.bash_stdin.close()
+            with contextlib.suppress(OSError):
+                self.bash_stdout.close()
+            self.process = None
 
-        assert isinstance(self.name, str)
+            keep_container = strtobool(os.environ.get("CIBW_DEBUG_KEEP_CONTAINER", ""))
+            if not keep_container:
+                self._remove_container()
 
-        keep_container = strtobool(os.environ.get("CIBW_DEBUG_KEEP_CONTAINER", ""))
-        if not keep_container:
-            subprocess.run(
-                [self.engine.name, "rm", "--force", "-v", self.name],
-                stdout=subprocess.DEVNULL,
-                check=False,
-            )
-            self.name = None
+    def _remove_container(self) -> None:
+        assert self.name is not None
+        result = subprocess.run(
+            [self.engine.name, "rm", "--force", "-v", self.name],
+            stdout=subprocess.DEVNULL,
+            check=False,
+        )
+        # only warn when not running in CI
+        if result.returncode != 0 and detect_ci_provider() is None:
+            msg = f"Failed to remove {self.name!r} container."
+            log.warning(msg)
+        self.name = None
 
     def copy_into(self, from_path: Path, to_path: PurePath) -> None:
         if from_path.is_dir():
@@ -525,13 +578,12 @@ class OCIContainer:
         return self.call(command, env=environment, capture_output=True)
 
     def debug_info(self) -> str:
+        command = [self.engine.name, "info"]
         if self.engine.name == "podman":
-            command = f"{self.engine.name} info --debug"
-        else:
-            command = f"{self.engine.name} info"
+            command.append("--debug")
+
         completed = subprocess.run(
             command,
-            shell=True,
             check=True,
             cwd=self.cwd,
             stdin=subprocess.PIPE,

cibuildwheel/options.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import collections
 import configparser
 import contextlib
@@ -8,9 +10,9 @@ import functools
 import shlex
 import textwrap
 import tomllib
-from collections.abc import Callable, Generator, Iterable, Mapping, Sequence, Set
+from collections.abc import Mapping, Sequence
 from pathlib import Path
-from typing import Any, Final, Literal, Self, assert_never
+from typing import assert_never
 
 from packaging.specifiers import SpecifierSet
 
@@ -27,6 +29,11 @@ from cibuildwheel.util import resources
 from cibuildwheel.util.helpers import format_safe, parse_key_value_string, strtobool, unwrap
 from cibuildwheel.util.packaging import DependencyConstraints
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Callable, Generator, Iterable, Set
+    from typing import Any, Final, Literal, Self
+
 MANYLINUX_ARCHS: Final[tuple[str, ...]] = (
     "x86_64",
     "i686",
@@ -113,6 +120,7 @@ class BuildOptions:
     before_all: str
     before_build: str | None
     xbuild_tools: list[str] | None
+    xbuild_files: dict[str, list[str]]
     repair_command: str
     manylinux_images: dict[str, str] | None
     musllinux_images: dict[str, str] | None
@@ -708,11 +716,12 @@ class Options:
 
     def _check_pinned_image(self, value: str, pinned_images: Mapping[str, str]) -> None:
         error_set = {"manylinux1", "manylinux2010", "manylinux_2_24", "musllinux_1_1"}
+        # Currently no warnings, next: https://github.com/pypa/manylinux/issues/1925
         warning_set: set[str] = set()
 
         if value in error_set:
             msg = (
-                f"cibuildwheel 3.x does not support the image {value!r}. Either upgrade to a "
+                f"cibuildwheel 4.x does not support the image {value!r}. Either upgrade to a "
                 "supported image or continue using the image by pinning it directly with"
                 " its full OCI registry '<name>{:<tag>|@<digest>}'."
             )
@@ -764,6 +773,14 @@ class Options:
             if xbuild_tools == ["\u0000"]:
                 xbuild_tools = None
 
+            xbuild_files = parse_key_value_string(
+                self.reader.get(
+                    "xbuild-files",
+                    option_format=ShlexTableFormat(sep="; ", pair_sep=":", allow_merge=False),
+                ),
+                kw_arg_names=["*"],
+            )
+
             test_sources = shlex.split(
                 self.reader.get(
                     "test-sources", option_format=ListFormat(sep=" ", quote=shlex.quote)
@@ -917,6 +934,7 @@ class Options:
                 before_all=before_all,
                 build_verbosity=build_verbosity,
                 xbuild_tools=xbuild_tools,
+                xbuild_files=xbuild_files,
                 repair_command=repair_command,
                 environment=environment,
                 dependency_constraints=dependency_constraints,

cibuildwheel/platforms/__init__.py

@@ -1,14 +1,21 @@
+from __future__ import annotations
+
 import sys
-from collections.abc import Sequence
-from pathlib import Path
-from typing import Final, Protocol
+from typing import Protocol
 
 from cibuildwheel import errors
-from cibuildwheel.architecture import Architecture
-from cibuildwheel.options import Options
 from cibuildwheel.platforms import android, ios, linux, macos, pyodide, windows
-from cibuildwheel.selector import BuildSelector
-from cibuildwheel.typing import GenericPythonConfiguration, PlatformName
+
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Sequence
+    from pathlib import Path
+    from typing import Final
+
+    from cibuildwheel.architecture import Architecture
+    from cibuildwheel.options import Options
+    from cibuildwheel.selector import BuildSelector
+    from cibuildwheel.typing import GenericPythonConfiguration, PlatformName
 
 
 class PlatformModule(Protocol):

cibuildwheel/platforms/android.py

@@ -1,15 +1,13 @@
-import csv
-import hashlib
+from __future__ import annotations
+
 import os
 import platform
 import re
 import shlex
 import shutil
 import subprocess
-import sysconfig
-from collections.abc import Iterable, Iterator, MutableMapping
+import sys
 from dataclasses import dataclass
-from os.path import relpath
 from pathlib import Path
 from pprint import pprint
 from runpy import run_path
@@ -18,9 +16,8 @@ from typing import Any
 
 from build import ProjectBuilder
 from build.env import IsolatedEnv
-from elftools.common.exceptions import ELFError
-from elftools.elf.elffile import ELFFile
 from filelock import FileLock
+from packaging.utils import canonicalize_name
 
 from cibuildwheel import errors, platforms  # pylint: disable=cyclic-import
 from cibuildwheel.architecture import Architecture, arch_synonym
@@ -31,18 +28,27 @@ from cibuildwheel.frontend import (
     prepare_config_settings,
 )
 from cibuildwheel.logger import log
-from cibuildwheel.options import BuildOptions, Options
-from cibuildwheel.selector import BuildSelector
 from cibuildwheel.util import resources
 from cibuildwheel.util.cmd import call, shell
-from cibuildwheel.util.file import CIBW_CACHE_PATH, copy_test_sources, download, move_file
+from cibuildwheel.util.file import (
+    CIBW_CACHE_PATH,
+    copy_test_sources,
+    download,
+    move_file,
+    remove_on_error,
+)
 from cibuildwheel.util.helpers import prepare_command
 from cibuildwheel.util.packaging import find_compatible_wheel
 from cibuildwheel.util.python_build_standalone import create_python_build_standalone_environment
 from cibuildwheel.venv import constraint_flags, find_uv, virtualenv
 
-RESOURCES_ANDROID = resources.PATH / "android"
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from cibuildwheel.options import BuildOptions, Options
+    from cibuildwheel.selector import BuildSelector
+    from cibuildwheel.typing import PathOrStr
 
+RESOURCES_ANDROID = resources.PATH / "android"
 ANDROID_TRIPLET = {
     "arm64_v8a": "aarch64-linux-android",
     "x86_64": "x86_64-linux-android",
@@ -67,6 +73,7 @@ class PythonConfiguration:
     version: str
     identifier: str
     url: str
+    sha256: str
 
     @property
     def arch(self) -> str:
@@ -140,9 +147,11 @@ def build(options: Options, tmp_path: Path) -> None:
             build_path.mkdir()
             python_dir = setup_target_python(config, build_path)
             build_env, android_env = setup_env(config, build_options, build_path, python_dir)
+
             state = BuildState(
                 config, build_options, build_path, python_dir, build_env, android_env
             )
+            setup_xbuild_files(state)
 
             compatible_wheel = find_compatible_wheel(built_wheels, config.identifier)
             if compatible_wheel:
@@ -157,7 +166,7 @@ def build(options: Options, tmp_path: Path) -> None:
                 repaired_wheel = repair_wheel(state, built_wheel)
                 run_audit(tmp_dir=tmp_path, build_options=build_options, wheel=repaired_wheel)
 
-            test_wheel(state, repaired_wheel, build_frontend=build_options.build_frontend.name)
+            test_wheel(state, repaired_wheel)
 
             output_wheel: Path | None = None
             if compatible_wheel is None:
@@ -179,7 +188,8 @@ def setup_target_python(config: PythonConfiguration, build_path: Path) -> Path:
     python_tgz = CIBW_CACHE_PATH / config.url.rpartition("/")[-1]
     with FileLock(f"{python_tgz}.lock"):
         if not python_tgz.exists():
-            download(config.url, python_tgz)
+            with remove_on_error(python_tgz):
+                download(config.url, python_tgz, sha256=config.sha256)
 
     python_dir = build_path / "python"
     python_dir.mkdir()
@@ -189,6 +199,11 @@ def setup_target_python(config: PythonConfiguration, build_path: Path) -> Path:
     # updated to Python versions that include the fix.
     call("patch", "-p1", "-i", RESOURCES_ANDROID / "android.patch", cwd=python_dir)
 
+    # Work around https://github.com/python/cpython/issues/138800. This can be removed
+    # once we've updated to Python versions that include the fix.
+    pc_path = python_dir / f"prefix/lib/pkgconfig/python-{config.version}.pc"
+    pc_path.write_text(pc_path.read_text().replace("$(BLDLIBRARY)", f"-lpython{config.version}"))
+
     return python_dir
 
 
@@ -202,13 +217,7 @@ def setup_env(
     * android_env, which uses the environment while simulating running on Android.
     """
     log.step("Setting up build environment...")
-    build_frontend = build_options.build_frontend.name
-    use_uv = build_frontend in {"build[uv]", "uv"}
-    uv_path = find_uv()
-    if use_uv and uv_path is None:
-        msg = "uv not found"
-        raise AssertionError(msg)
-    pip = ["pip"] if not use_uv else [str(uv_path), "pip"]
+    use_uv, pip = find_pip(build_options)
 
     # Create virtual environment
     python_exe = create_python_build_standalone_environment(
@@ -223,8 +232,12 @@ def setup_env(
     )
     create_cmake_toolchain(config, build_path, python_dir, build_env)
 
+    # See platforms.md for the reason why we use this default API level.
+    build_env.setdefault("ANDROID_API_LEVEL", "24")
+
     # Apply custom environment variables, and check environment is still valid
     build_env = build_options.environment.as_dictionary(build_env)
+    build_env["CIBUILDWHEEL_BUILD_IDENTIFIER"] = config.identifier
     build_env["PIP_DISABLE_PIP_VERSION_CHECK"] = "1"
     for command in ["python"] if use_uv else ["python", "pip"]:
         command_path = call("which", command, env=build_env, capture_stdout=True).strip()
@@ -240,14 +253,14 @@ def setup_env(
         else:
             call(command, "--version", env=build_env)
 
-    # Construct an altered environment which simulates running on Android.
-    android_env = setup_android_env(config, python_dir, venv_dir, build_env)
-
     # Install build tools
-    if build_frontend not in {"build", "build[uv]", "uv"}:
-        msg = "Android requires the build frontend to be 'build' or 'uv'"
-        raise errors.FatalError(msg)
-    call(*pip, "install", "build", *constraint_flags(dependency_constraint), env=build_env)
+    tools = ["auditwheel", "patchelf", "pkgconf"]
+    if build_options.build_frontend.name in {"build", "build[uv]"}:
+        tools.append("build")
+    call(*pip, "install", *tools, *constraint_flags(dependency_constraint), env=build_env)
+
+    # Construct an altered environment which simulates running on Android.
+    android_env = setup_android_env(config, python_dir, build_env)
 
     # Build-time requirements must be queried within android_env, because
     # `get_requires_for_build` can run arbitrary code in setup.py scripts, which may be
@@ -270,7 +283,12 @@ def setup_env(
         call(*pip, "install", *pb.build_system_requires, env=build_env)
 
     requires_for_build = pb.get_requires_for_build(
-        "wheel", parse_config_settings(build_options.config_settings)
+        "wheel",
+        parse_config_settings(
+            prepare_config_settings(
+                build_options.config_settings, project=".", package=build_options.package_dir
+            )
+        ),
     )
     if requires_for_build:
         call(*pip, "install", *requires_for_build, env=build_env)
@@ -338,8 +356,11 @@ def localized_vars(
             final = final.replace(orig_prefix, str(prefix))
 
         if key == "ANDROID_API_LEVEL":
-            if api_level := build_env.get(key):
-                final = int(api_level)
+            try:
+                final = int(build_env[key])
+            except ValueError as e:
+                msg = f"ANDROID_API_LEVEL: {e}. This variable must be an integer."
+                raise errors.FatalError(msg) from e
 
         # Build systems vary in whether FLAGS variables are read from sysconfig, and if so,
         # whether they're replaced by environment variables or combined with them. Even
@@ -362,15 +383,15 @@ def localized_vars(
 
 
 def setup_android_env(
-    config: PythonConfiguration, python_dir: Path, venv_dir: Path, build_env: dict[str, str]
+    config: PythonConfiguration, python_dir: Path, build_env: dict[str, str]
 ) -> dict[str, str]:
-    site_packages = next(venv_dir.glob("lib/python*/site-packages"))
+    site_packages = find_site_packages(build_env)
     for suffix in ["pth", "py"]:
         shutil.copy(RESOURCES_ANDROID / f"_cross_venv.{suffix}", site_packages)
 
     sysconfigdata_path = Path(
         shutil.copy(
-            next(python_dir.glob("prefix/lib/python*/_sysconfigdata_*.py")),
+            glob1(python_dir, "prefix/lib/python*/_sysconfigdata_*.py"),
             site_packages,
         )
     )
@@ -409,6 +430,17 @@ def setup_android_env(
     # Cargo target linker needs to be specified after CC is set
     setup_rust(config, python_dir, android_env)
 
+    # Create shims which install additional build tools on first use.
+    setup_fortran(android_env)
+
+    # `android.py env` returns PKG_CONFIG="pkg-config --define-prefix", but some build
+    # systems can't handle arguments in that variable. Since we have a known version
+    # of pkgconf, it's safe to use PKG_CONFIG_RELOCATE_PATHS instead.
+    android_env["PKG_CONFIG"] = call(
+        "which", "pkgconf-pypi", env=build_env, capture_stdout=True
+    ).strip()
+    android_env["PKG_CONFIG_RELOCATE_PATHS"] = "1"
+
     # Format the environment so it can be pasted into a shell when debugging.
     for key, value in sorted(android_env.items()):
         if os.environ.get(key) != value:
@@ -417,11 +449,7 @@ def setup_android_env(
     return android_env
 
 
-def setup_rust(
-    config: PythonConfiguration,
-    python_dir: Path,
-    env: MutableMapping[str, str],
-) -> None:
+def setup_rust(config: PythonConfiguration, python_dir: Path, env: dict[str, str]) -> None:
     cargo_target = android_triplet(config.identifier)
 
     # CARGO_BUILD_TARGET is the variable used by Cargo and setuptools_rust
@@ -445,13 +473,83 @@ def setup_rust(
         shim_path.chmod(0o755)
 
 
+def setup_fortran(env: dict[str, str]) -> None:
+    # In case there's any autodetection based on the executable name, use the same name
+    # as the real executable (see fortran_shim.run_flang)
+    shim_in = RESOURCES_ANDROID / "fortran_shim.py"
+    shim_out = Path(env["VIRTUAL_ENV"]) / "bin/flang-new"
+
+    # The hashbang line runs the shim in cibuildwheel's own virtual environment, so it
+    # has access to utility functions for downloading and caching files.
+    shim_out.write_text(f"#!{sys.executable}\n\n" + shim_in.read_text())
+    shim_out.chmod(0o755)
+    env["FC"] = str(shim_out)
+
+
+def setup_xbuild_files(state: BuildState) -> None:
+    _, pip = find_pip(state.options)
+    xbf_dir = state.build_path / "xbuild_files"
+    xbf_dir.mkdir()
+
+    for requirement in call(*pip, "freeze", env=state.build_env, capture_stdout=True).splitlines():
+        name, _, _ = requirement.strip().partition("==")
+        xbuild_files = state.options.xbuild_files.get(canonicalize_name(name), [])
+        if xbuild_files:
+            log.step(f"Installing xbuild-files for {name}...")
+            pip_install_android(state, xbf_dir, "--no-deps", requirement)
+            for xbf in xbuild_files:
+                if (xbf_dir / xbf).exists():
+                    shutil.copy(
+                        xbf_dir / xbf,
+                        find_site_packages(state.build_env) / xbf,
+                    )
+                else:
+                    log.warning(f"{xbf_dir / xbf} does not exist")
+
+
+def pip_install_android(state: BuildState, target: Path, *args: PathOrStr) -> None:
+    use_uv, pip = find_pip(state.options)
+    call(
+        *pip,
+        "install",
+        "--only-binary=:all:",
+        *(["--python-platform", android_triplet(state.config.identifier)] if use_uv else []),
+        "--target",
+        target,
+        *args,
+        env=state.android_env,
+    )
+
+
+def find_site_packages(env: dict[str, str]) -> Path:
+    return glob1(Path(env["VIRTUAL_ENV"]), "lib/python*/site-packages")
+
+
+def glob1(base: Path, pattern: str) -> Path:
+    results = list(base.glob(pattern))
+    if len(results) != 1:
+        msg = f"{base} contains {len(results)} paths matching '{pattern}'; expected 1"
+        raise errors.FatalError(msg)
+    return results[0]
+
+
+def find_pip(build_options: BuildOptions) -> tuple[bool, list[str]]:
+    use_uv = build_options.build_frontend.name in {"build[uv]", "uv"}
+    uv_path = find_uv()
+    if use_uv and uv_path is None:
+        msg = "uv not found"
+        raise AssertionError(msg)
+    pip = ["pip"] if not use_uv else [str(uv_path), "pip"]
+    return use_uv, pip
+
+
 def before_build(state: BuildState) -> None:
     if state.options.before_build:
         log.step("Running before_build...")
         shell_prepared(
             state.options.before_build,
             build_options=state.options,
-            env=state.build_env,
+            env=state.android_env,
         )
 
 
@@ -502,15 +600,10 @@ def build_wheel(state: BuildState) -> Path:
                 env=state.android_env,
             )
         case x:
-            msg = f"Invalid build backend {x!r}"
-            raise AssertionError(msg)
-
-    built_wheels = list(built_wheel_dir.glob("*.whl"))
-    if len(built_wheels) != 1:
-        msg = f"{built_wheel_dir} contains {len(built_wheels)} wheels; expected 1"
-        raise errors.FatalError(msg)
-    built_wheel = built_wheels[0]
+            msg = f"Android requires the build frontend to be 'build' or 'uv', not {x!r}"
+            raise errors.FatalError(msg)
 
+    built_wheel = glob1(built_wheel_dir, "*.whl")
     if built_wheel.name.endswith("none-any.whl"):
         raise errors.NonPlatformWheelError()
     return built_wheel
@@ -522,9 +615,20 @@ def repair_wheel(state: BuildState, built_wheel: Path) -> Path:
     repaired_wheel_dir.mkdir()
 
     if state.options.repair_command:
+        # Tell auditwheel the locations of compiler libraries.
+        toolchain = Path(state.android_env["CC"]).parent.parent
+        triplet = android_triplet(state.config.identifier)
+        ldpaths = ":".join(
+            str(glob1(toolchain, pattern))
+            for pattern in [
+                f"lib/clang/*/lib/linux/{triplet.split('-')[0]}",  # libomp
+                f"sysroot/usr/lib/{triplet}",  # libc++_shared
+            ]
+        )
         shell(
             prepare_command(
                 state.options.repair_command,
+                ldpaths=ldpaths,
                 wheel=built_wheel,
                 dest_dir=repaired_wheel_dir,
                 package=state.options.package_dir,
@@ -533,14 +637,15 @@ def repair_wheel(state: BuildState, built_wheel: Path) -> Path:
             env=state.build_env,
         )
     else:
-        repair_default(state.android_env, built_wheel, repaired_wheel_dir)
+        shutil.move(built_wheel, repaired_wheel_dir)
 
     repaired_wheels = list(repaired_wheel_dir.glob("*.whl"))
     if len(repaired_wheels) == 0:
         raise errors.RepairStepProducedNoWheelError()
     if len(repaired_wheels) != 1:
-        msg = f"{repaired_wheel_dir} contains {len(repaired_wheels)} wheels; expected 1"
-        raise errors.FatalError(msg)
+        raise errors.RepairStepProducedMultipleWheelsError(
+            [rw.name for rw in repaired_wheels],
+        )
     repaired_wheel = repaired_wheels[0]
 
     if repaired_wheel.name.endswith("none-any.whl"):
@@ -548,119 +653,12 @@ def repair_wheel(state: BuildState, built_wheel: Path) -> Path:
     return repaired_wheel
 
 
-def repair_default(
-    android_env: dict[str, str], built_wheel: Path, repaired_wheel_dir: Path
-) -> None:
-    """
-    Adds libc++ to the wheel if anything links against it. In the future this should be
-    moved to auditwheel and generalized to support more libraries.
-    """
-    if (match := re.search(r"^(.+?)-", built_wheel.name)) is None:
-        msg = f"Failed to parse wheel filename: {built_wheel.name}"
-        raise errors.FatalError(msg)
-    wheel_name = match[1]
-
-    unpacked_dir = repaired_wheel_dir / "unpacked"
-    unpacked_dir.mkdir()
-    shutil.unpack_archive(built_wheel, unpacked_dir, format="zip")
-
-    # Some build systems are inconsistent about name normalization, so don't assume the
-    # dist-info name is identical to the wheel name.
-    record_paths = list(unpacked_dir.glob("*.dist-info/RECORD"))
-    if len(record_paths) != 1:
-        msg = f"{built_wheel.name} contains {len(record_paths)} dist-info/RECORD files; expected 1"
-        raise errors.FatalError(msg)
-
-    old_soname = "libc++_shared.so"
-    paths_to_patch = []
-    for path, elffile in elf_file_filter(
-        unpacked_dir / filename
-        for filename, *_ in csv.reader(record_paths[0].read_text().splitlines())
-    ):
-        if (dynamic := elffile.get_section_by_name(".dynamic")) and any(  # type: ignore[no-untyped-call]
-            tag.entry.d_tag == "DT_NEEDED" and tag.needed == old_soname
-            for tag in dynamic.iter_tags()
-        ):
-            paths_to_patch.append(path)
-
-    if not paths_to_patch:
-        shutil.copyfile(built_wheel, repaired_wheel_dir / built_wheel.name)
-    else:
-        # Android doesn't support DT_RPATH, but supports DT_RUNPATH since API level 24
-        # (https://github.com/aosp-mirror/platform_bionic/blob/master/android-changes-for-ndk-developers.md).
-        if int(sysconfig_print('get_config_vars()["ANDROID_API_LEVEL"]', android_env)) < 24:
-            msg = f"Adding {old_soname} requires ANDROID_API_LEVEL to be at least 24"
-            raise errors.FatalError(msg)
-
-        toolchain = Path(android_env["CC"]).parent.parent
-        src_path = toolchain / f"sysroot/usr/lib/{android_env['CIBW_HOST_TRIPLET']}/{old_soname}"
-
-        # Use the same library location as auditwheel would.
-        libs_dir = unpacked_dir / (wheel_name + ".libs")
-        libs_dir.mkdir()
-        new_soname = soname_with_hash(src_path)
-        dst_path = libs_dir / new_soname
-        shutil.copyfile(src_path, dst_path)
-        call(which("patchelf"), "--set-soname", new_soname, dst_path)
-
-        for path in paths_to_patch:
-            call(which("patchelf"), "--replace-needed", old_soname, new_soname, path)
-            call(
-                which("patchelf"),
-                "--set-rpath",
-                f"${{ORIGIN}}/{relpath(libs_dir, path.parent)}",
-                path,
-            )
-        call(which("wheel"), "pack", unpacked_dir, "-d", repaired_wheel_dir)
-
-
-# If cibuildwheel was called without activating its environment, its scripts directory
-# will not be on the PATH.
-def which(cmd: str) -> str:
-    scripts_dir = sysconfig.get_path("scripts")
-    result = shutil.which(cmd, path=scripts_dir + os.pathsep + os.environ["PATH"])
-    if result is None:
-        msg = f"Couldn't find {cmd!r} in {scripts_dir} or on the PATH"
-        raise errors.FatalError(msg)
-    return result
-
-
-def elf_file_filter(paths: Iterable[Path]) -> Iterator[tuple[Path, ELFFile]]:
-    """Filter through an iterator of filenames and load up only ELF files"""
-    for path in paths:
-        if not path.name.endswith(".py"):
-            try:
-                with open(path, "rb") as f:
-                    candidate = ELFFile(f)  # type: ignore[no-untyped-call]
-                    yield path, candidate
-            except ELFError:
-                pass  # Not an ELF file
-
-
-def soname_with_hash(src_path: Path) -> str:
-    """Return the same library filename as auditwheel would"""
-    shorthash = hashlib.sha256(src_path.read_bytes()).hexdigest()[:8]
-    src_name = src_path.name
-    base, ext = src_name.split(".", 1)
-    if not base.endswith(f"-{shorthash}"):
-        return f"{base}-{shorthash}.{ext}"
-    else:
-        return src_name
-
-
-def test_wheel(state: BuildState, wheel: Path, *, build_frontend: str) -> None:
+def test_wheel(state: BuildState, wheel: Path) -> None:
     test_command = state.options.test_command
     if not (test_command and state.options.test_selector(state.config.identifier)):
         return
 
     log.step("Testing wheel...")
-    use_uv = build_frontend in {"build[uv]", "uv"}
-    uv_path = find_uv()
-    if use_uv and uv_path is None:
-        msg = "uv not found"
-        raise AssertionError(msg)
-    pip = ["pip"] if not use_uv else [str(uv_path), "pip"]
-
     native_arch = arch_synonym(platform.machine(), platforms.native_platform(), "android")
     if state.config.arch != native_arch:
         log.warning(
@@ -673,31 +671,17 @@ def test_wheel(state: BuildState, wheel: Path, *, build_frontend: str) -> None:
         shell_prepared(
             state.options.before_test,
             build_options=state.options,
-            env=state.build_env,
+            env=state.android_env,
         )
 
-    platform_args = (
-        ["--python-platform", android_triplet(state.config.identifier)]
-        if use_uv
-        else [
-            "--platform",
-            sysconfig_print("get_platform()", state.android_env).replace("-", "_"),
-        ]
-    )
-
     # Install the wheel and test-requires.
     site_packages_dir = state.build_path / "site-packages"
     site_packages_dir.mkdir()
-    call(
-        *pip,
-        "install",
-        "--only-binary=:all:",
-        *platform_args,
-        "--target",
+    pip_install_android(
+        state,
         site_packages_dir,
         f"{wheel}{state.options.test_extras}",
         *state.options.test_requires,
-        env=state.android_env,
     )
 
     # Copy test-sources.
@@ -767,13 +751,3 @@ def test_wheel(state: BuildState, wheel: Path, *, build_frontend: str) -> None:
         *test_args,
         env=state.build_env,
     )
-
-
-def sysconfig_print(method_call: str, env: dict[str, str]) -> str:
-    return call(
-        "python",
-        "-c",
-        f'import sysconfig; print(sysconfig.{method_call}, end="")',
-        env=env,
-        capture_stdout=True,
-    )

cibuildwheel/platforms/ios.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import dataclasses
 import os
 import platform
@@ -6,32 +8,43 @@ import shutil
 import subprocess
 import sys
 import textwrap
-from collections.abc import Sequence, Set
 from pathlib import Path
 from typing import assert_never
 
 from filelock import FileLock
+from packaging.version import Version
 
 from cibuildwheel import errors
-from cibuildwheel.architecture import Architecture
 from cibuildwheel.audit import run_audit
-from cibuildwheel.environment import ParsedEnvironment
 from cibuildwheel.frontend import (
     BuildFrontendName,
     get_build_frontend_extra_flags,
     prepare_config_settings,
 )
 from cibuildwheel.logger import log
-from cibuildwheel.options import Options
 from cibuildwheel.platforms.macos import install_cpython as install_build_cpython
-from cibuildwheel.selector import BuildSelector
 from cibuildwheel.util import resources
 from cibuildwheel.util.cmd import call, shell, split_command
-from cibuildwheel.util.file import CIBW_CACHE_PATH, copy_test_sources, download, move_file
+from cibuildwheel.util.file import (
+    CIBW_CACHE_PATH,
+    copy_test_sources,
+    download,
+    move_file,
+    remove_on_error,
+)
 from cibuildwheel.util.helpers import prepare_command, unwrap_preserving_paragraphs
 from cibuildwheel.util.packaging import find_compatible_wheel
 from cibuildwheel.venv import constraint_flags, virtualenv
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Sequence, Set
+
+    from cibuildwheel.architecture import Architecture
+    from cibuildwheel.environment import ParsedEnvironment
+    from cibuildwheel.options import Options
+    from cibuildwheel.selector import BuildSelector
+
 
 @dataclasses.dataclass(frozen=True, kw_only=True)
 class PythonConfiguration:
@@ -39,6 +52,8 @@ class PythonConfiguration:
     identifier: str
     url: str
     build_url: str
+    build_sha256: str
+    sha256: str
 
     @property
     def sdk(self) -> str:
@@ -71,7 +86,7 @@ def all_python_configurations() -> list[PythonConfiguration]:
     # configuration.
     macos_python_configs = resources.read_python_configs("macos")
 
-    def build_url(config_dict: dict[str, str]) -> str:
+    def build_python_config(config_dict: dict[str, str]) -> dict[str, str]:
         # The iOS identifier will be something like cp313-ios_arm64_iphoneos.
         # Drop the iphoneos suffix, then replace ios with macosx to yield
         # cp313-macosx_arm64, which will be a macOS build identifier.
@@ -80,18 +95,22 @@ def all_python_configurations() -> list[PythonConfiguration]:
         matching = [
             config for config in macos_python_configs if config["identifier"] == macos_identifier
         ]
-        return matching[0]["url"]
+        return matching[0]
 
     # Load the platform configuration
     full_python_configs = resources.read_python_configs("ios")
     # Build the configurations, annotating with macOS URL details.
-    return [
-        PythonConfiguration(
-            **item,
-            build_url=build_url(item),
+    python_configurations = []
+    for item in full_python_configs:
+        build_config = build_python_config(item)
+        python_configurations.append(
+            PythonConfiguration(
+                **item,
+                build_url=build_config["url"],
+                build_sha256=build_config["sha256"],
+            )
         )
-        for item in full_python_configs
-    ]
+    return python_configurations
 
 
 def get_python_configurations(
@@ -126,9 +145,10 @@ def install_target_cpython(tmp: Path, config: PythonConfiguration, free_threadin
     with FileLock(str(installation_path) + ".lock"):
         if not installation_path.exists():
             downloaded_tar_gz = tmp / ios_python_tar_gz
-            download(config.url, downloaded_tar_gz)
-            installation_path.mkdir(parents=True, exist_ok=True)
-            call("tar", "-C", installation_path, "-xf", downloaded_tar_gz)
+            download(config.url, downloaded_tar_gz, sha256=config.sha256)
+            with remove_on_error(installation_path):
+                installation_path.mkdir(parents=True)
+                call("tar", "-C", installation_path, "-xf", downloaded_tar_gz)
             downloaded_tar_gz.unlink()
 
     return installation_path
@@ -183,18 +203,37 @@ def cross_virtualenv(
     )
 
     # Convert the macOS virtual environment into an iOS virtual environment
-    # using the cross-platform conversion script in the iOS distribution.
+    # using make_cross_venv.py.
 
     # target_python is the path to the Python binary;
     # determine the root of the XCframework slice that is being used.
     slice_path = target_python.parent.parent
-    call(
-        "python",
-        str(slice_path / f"platform-config/{multiarch}/make_cross_venv.py"),
-        str(venv_path),
-        env=env,
-        cwd=venv_path,
-    )
+    if Version(py_version) >= Version("3.15"):
+        # python.org 3.15+ distributions: sysconfig data lives in the
+        # stdlib directory (lib-<arch>/python<version>); cross-venv scripts
+        # come from cibuildwheel resources.
+        arch = multiarch.split("-", maxsplit=1)[0]
+        stdlib_path = slice_path / f"lib-{arch}" / f"python{py_version}"
+        call(
+            "python",
+            str(resources.IOS_SUPPORT_FILES / "make_cross_venv.py"),
+            str(venv_path),
+            str(stdlib_path),
+            str(resources.IOS_SUPPORT_FILES),
+            env=env,
+            cwd=venv_path,
+        )
+    else:
+        # BeeWare distributions: platform-config already contains both
+        # sysconfig data and the make_cross_venv.py script.
+        platform_config_path = slice_path / f"platform-config/{multiarch}"
+        call(
+            "python",
+            str(platform_config_path / "make_cross_venv.py"),
+            str(venv_path),
+            env=env,
+            cwd=venv_path,
+        )
 
     # When running on macOS, it's easy for the build environment to leak into
     # the target environment, especially when building for ARM64 (because the
@@ -293,6 +332,7 @@ def setup_python(
             python_configuration.version,
             python_configuration.build_url,
             free_threading,
+            python_configuration.build_sha256,
         )
     else:
         msg = f"Unknown Python implementation: {implementation_id}"
@@ -312,8 +352,8 @@ def setup_python(
         / f"python{python_configuration.version}"
     )
 
-    assert target_python.exists(), (
-        f"{target_python.name} not found, has {list(target_install_path.iterdir())}"
+    assert target_python.parent.exists(), (
+        f"{target_python.parent} not found, has {list(target_install_path.iterdir())}"
     )
 
     log.step("Creating cross build environment...")
@@ -456,6 +496,7 @@ def build(options: Options, tmp_path: Path) -> None:
                 build_frontend=build_frontend.name,
                 xbuild_tools=build_options.xbuild_tools,
             )
+            env["CIBUILDWHEEL_BUILD_IDENTIFIER"] = config.identifier
 
             compatible_wheel = find_compatible_wheel(built_wheels, config.identifier)
             if compatible_wheel:

cibuildwheel/platforms/linux.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import contextlib
 import dataclasses
 import shutil
@@ -5,9 +7,8 @@ import subprocess
 import sys
 import textwrap
 from collections import OrderedDict
-from collections.abc import Iterable, Iterator, Sequence, Set
 from pathlib import Path, PurePath, PurePosixPath
-from typing import TYPE_CHECKING, assert_never
+from typing import assert_never
 
 from cibuildwheel import errors
 from cibuildwheel.architecture import Architecture
@@ -15,14 +16,17 @@ from cibuildwheel.audit import needs_audit, run_audit
 from cibuildwheel.frontend import get_build_frontend_extra_flags, prepare_config_settings
 from cibuildwheel.logger import log
 from cibuildwheel.oci_container import OCIContainer, OCIContainerEngineConfig, OCIPlatform
-from cibuildwheel.options import BuildOptions, Options
-from cibuildwheel.selector import BuildSelector
 from cibuildwheel.util import resources
 from cibuildwheel.util.file import copy_test_sources
 from cibuildwheel.util.helpers import prepare_command, unwrap
 from cibuildwheel.util.packaging import find_compatible_wheel
 
+TYPE_CHECKING = False
 if TYPE_CHECKING:
+    from collections.abc import Iterable, Iterator, Sequence, Set
+
+    from cibuildwheel.options import BuildOptions, Options
+    from cibuildwheel.selector import BuildSelector
     from cibuildwheel.typing import PathOrStr
 
 ARCHITECTURE_OCI_PLATFORM_MAP = {
@@ -233,6 +237,7 @@ def build_in_container(
         env["PATH"] = f"{python_bin}:{env['PATH']}"
 
         env = build_options.environment.as_dictionary(env, executor=container.environment_executor)
+        env["CIBUILDWHEEL_BUILD_IDENTIFIER"] = config.identifier
 
         # check config python is still on PATH
         which_python = container.call(["which", "python"], env=env, capture_output=True).strip()

cibuildwheel/platforms/macos.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import dataclasses
 import functools
 import inspect
@@ -8,33 +10,44 @@ import shutil
 import subprocess
 import sys
 import typing
-from collections.abc import Set
 from pathlib import Path
-from typing import Literal, assert_never
+from typing import assert_never
 
 from filelock import FileLock
 from packaging.version import Version
 
 from cibuildwheel import errors
-from cibuildwheel.architecture import Architecture
 from cibuildwheel.audit import run_audit
 from cibuildwheel.ci import detect_ci_provider
-from cibuildwheel.environment import ParsedEnvironment
 from cibuildwheel.frontend import (
     BuildFrontendName,
     get_build_frontend_extra_flags,
     prepare_config_settings,
 )
 from cibuildwheel.logger import log
-from cibuildwheel.options import Options
-from cibuildwheel.selector import BuildSelector
 from cibuildwheel.util import resources
 from cibuildwheel.util.cmd import call, shell
-from cibuildwheel.util.file import CIBW_CACHE_PATH, copy_test_sources, download, move_file
+from cibuildwheel.util.file import (
+    CIBW_CACHE_PATH,
+    copy_test_sources,
+    download,
+    move_file,
+    remove_on_error,
+)
 from cibuildwheel.util.helpers import prepare_command, unwrap
 from cibuildwheel.util.packaging import find_compatible_wheel, get_pip_version
 from cibuildwheel.venv import constraint_flags, find_uv, target_marker_env, virtualenv
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Set
+    from typing import Literal
+
+    from cibuildwheel.architecture import Architecture
+    from cibuildwheel.environment import ParsedEnvironment
+    from cibuildwheel.options import Options
+    from cibuildwheel.selector import BuildSelector
+
 
 @functools.cache
 def get_macos_version() -> tuple[int, int]:
@@ -81,6 +94,7 @@ class PythonConfiguration:
     version: str
     identifier: str
     url: str
+    sha256: str
 
 
 def all_python_configurations() -> list[PythonConfiguration]:
@@ -128,7 +142,7 @@ def get_python_configurations(
     return python_configurations
 
 
-def install_cpython(_tmp: Path, version: str, url: str, free_threading: bool) -> Path:
+def install_cpython(_tmp: Path, version: str, url: str, free_threading: bool, sha256: str) -> Path:
     ft = "T" if free_threading else ""
     installation_path = Path(f"/Library/Frameworks/Python{ft}.framework/Versions/{version}")
     with FileLock(CIBW_CACHE_PATH / f"cpython{version}.lock"):
@@ -154,7 +168,7 @@ def install_cpython(_tmp: Path, version: str, url: str, free_threading: bool) ->
             python_filename = url.rsplit("/", maxsplit=1)[-1]
             pkg_path = CIBW_CACHE_PATH / "cpython-installer" / python_filename
             if not pkg_path.exists():
-                download(url, pkg_path)
+                download(url, pkg_path, sha256=sha256)
             args = []
             if version.startswith("3.14"):
                 args += ["-applyChoiceChangesXML", str(resources.FREE_THREAD_ENABLE_314.resolve())]
@@ -178,7 +192,7 @@ def install_cpython(_tmp: Path, version: str, url: str, free_threading: bool) ->
     return installation_path / "bin" / (f"python{version}t" if free_threading else "python3")
 
 
-def install_pypy(tmp: Path, url: str) -> Path:
+def install_pypy(tmp: Path, url: str, sha256: str) -> Path:
     pypy_tar_bz2 = url.rsplit("/", 1)[-1]
     extension = ".tar.bz2"
     assert pypy_tar_bz2.endswith(extension)
@@ -186,14 +200,15 @@ def install_pypy(tmp: Path, url: str) -> Path:
     with FileLock(str(installation_path) + ".lock"):
         if not installation_path.exists():
             downloaded_tar_bz2 = tmp / pypy_tar_bz2
-            download(url, downloaded_tar_bz2)
+            download(url, downloaded_tar_bz2, sha256=sha256)
             installation_path.parent.mkdir(parents=True, exist_ok=True)
-            call("tar", "-C", installation_path.parent, "-xf", downloaded_tar_bz2)
+            with remove_on_error(installation_path):
+                call("tar", "-C", installation_path.parent, "-xf", downloaded_tar_bz2)
             downloaded_tar_bz2.unlink()
     return installation_path / "bin" / "pypy3"
 
 
-def install_graalpy(tmp: Path, url: str) -> Path:
+def install_graalpy(tmp: Path, url: str, sha256: str) -> Path:
     graalpy_archive = url.rsplit("/", 1)[-1]
     extension = ".tar.gz"
     assert graalpy_archive.endswith(extension)
@@ -201,10 +216,18 @@ def install_graalpy(tmp: Path, url: str) -> Path:
     with FileLock(str(installation_path) + ".lock"):
         if not installation_path.exists():
             downloaded_archive = tmp / graalpy_archive
-            download(url, downloaded_archive)
-            installation_path.mkdir(parents=True)
-            # GraalPy top-folder name is inconsistent with archive name
-            call("tar", "-C", installation_path, "--strip-components=1", "-xzf", downloaded_archive)
+            download(url, downloaded_archive, sha256=sha256)
+            with remove_on_error(installation_path):
+                installation_path.mkdir(parents=True)
+                # GraalPy top-folder name is inconsistent with archive name
+                call(
+                    "tar",
+                    "-C",
+                    installation_path,
+                    "--strip-components=1",
+                    "-xzf",
+                    downloaded_archive,
+                )
             downloaded_archive.unlink()
     return installation_path / "bin" / "graalpy"
 
@@ -225,13 +248,17 @@ def setup_python(
     if implementation_id.startswith("cp"):
         free_threading = "t-macos" in python_configuration.identifier
         base_python = install_cpython(
-            tmp, python_configuration.version, python_configuration.url, free_threading
+            tmp,
+            python_configuration.version,
+            python_configuration.url,
+            free_threading,
+            python_configuration.sha256,
         )
 
     elif implementation_id.startswith("pp"):
-        base_python = install_pypy(tmp, python_configuration.url)
+        base_python = install_pypy(tmp, python_configuration.url, python_configuration.sha256)
     elif implementation_id.startswith("gp"):
-        base_python = install_graalpy(tmp, python_configuration.url)
+        base_python = install_graalpy(tmp, python_configuration.url, python_configuration.sha256)
     else:
         msg = "Unknown Python implementation"
         raise ValueError(msg)
@@ -459,6 +486,7 @@ def build(options: Options, tmp_path: Path) -> None:
                 build_options.environment,
                 build_frontend.name,
             )
+            env["CIBUILDWHEEL_BUILD_IDENTIFIER"] = config.identifier
             pip_version = None if use_uv else get_pip_version(env)
 
             compatible_wheel = find_compatible_wheel(built_wheels, config.identifier)

cibuildwheel/platforms/pyodide.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import dataclasses
 import functools
 import json
@@ -7,7 +9,6 @@ import subprocess
 import sys
 import tomllib
 import typing
-from collections.abc import Set
 from pathlib import Path
 from tempfile import TemporaryDirectory
 from typing import Final, TypedDict
@@ -17,11 +18,8 @@ from filelock import FileLock
 from cibuildwheel import errors
 from cibuildwheel.architecture import Architecture
 from cibuildwheel.audit import run_audit
-from cibuildwheel.environment import ParsedEnvironment
 from cibuildwheel.frontend import get_build_frontend_extra_flags, prepare_config_settings
 from cibuildwheel.logger import log
-from cibuildwheel.options import Options
-from cibuildwheel.selector import BuildSelector
 from cibuildwheel.util import resources
 from cibuildwheel.util.cmd import call, shell
 from cibuildwheel.util.file import (
@@ -31,6 +29,7 @@ from cibuildwheel.util.file import (
     extract_tar,
     extract_zip,
     move_file,
+    remove_on_error,
 )
 from cibuildwheel.util.helpers import prepare_command, unwrap, unwrap_preserving_paragraphs
 from cibuildwheel.util.packaging import find_compatible_wheel, get_pip_version
@@ -40,6 +39,14 @@ from cibuildwheel.util.python_build_standalone import (
 )
 from cibuildwheel.venv import constraint_flags, virtualenv
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Set
+
+    from cibuildwheel.environment import ParsedEnvironment
+    from cibuildwheel.options import Options
+    from cibuildwheel.selector import BuildSelector
+
 IS_WIN: Final[bool] = sys.platform.startswith("win")
 
 
@@ -49,6 +56,7 @@ class PythonConfiguration:
     identifier: str
     default_pyodide_version: str
     node_version: str
+    sha256: str = ""
 
 
 class PyodideXBuildEnvInfoVersionRange(TypedDict):
@@ -85,10 +93,11 @@ def ensure_node(major_version: str) -> Path:
             with TemporaryDirectory() as tmp_path:
                 archive = Path(tmp_path) / f"{name}.{ext}"
                 download(url, archive)
-                if ext == "zip":
-                    extract_zip(archive, path.parent)
-                else:
-                    extract_tar(archive, path.parent)
+                with remove_on_error(path):
+                    if ext == "zip":
+                        extract_zip(archive, path.parent)
+                    else:
+                        extract_tar(archive, path.parent)
     assert path.exists()
     if not IS_WIN:
         return path / "bin"
@@ -103,18 +112,19 @@ def install_emscripten(env: dict[str, str], version: str, xbuildenv_cache_path:
     with FileLock(CIBW_CACHE_PATH / "emscripten.lock"):
         if emscripten_dir.exists():
             return emscripten_dir
-        call(
-            "pyodide",
-            "xbuildenv",
-            "install-emscripten",
-            "--force",
-            "--version",
-            version,
-            "--path",
-            str(xbuildenv_cache_path),
-            env=env,
-            cwd=CIBW_CACHE_PATH,
-        )
+        with remove_on_error(emscripten_dir):
+            call(
+                "pyodide",
+                "xbuildenv",
+                "install-emscripten",
+                "--force",
+                "--version",
+                version,
+                "--path",
+                str(xbuildenv_cache_path),
+                env=env,
+                cwd=CIBW_CACHE_PATH,
+            )
     assert emscripten_dir.exists()
     return emscripten_dir
 
@@ -201,17 +211,18 @@ def install_xbuildenv(env: dict[str, str], xbuildenv_cache_path: Path, pyodide_v
         env.pop("PYODIDE_ROOT", None)
 
         # Install the xbuildenv
-        call(
-            "pyodide",
-            "xbuildenv",
-            "install",
-            "--path",
-            str(xbuildenv_cache_path),
-            pyodide_version,
-            env=env,
-            cwd=CIBW_CACHE_PATH,
-        )
-        assert pyodide_root.exists()
+        with remove_on_error(xbuildenv_cache_path / pyodide_version):
+            call(
+                "pyodide",
+                "xbuildenv",
+                "install",
+                "--path",
+                str(xbuildenv_cache_path),
+                pyodide_version,
+                env=env,
+                cwd=CIBW_CACHE_PATH,
+            )
+            assert pyodide_root.exists()
 
     return str(pyodide_root)
 
@@ -385,6 +396,7 @@ def build(options: Options, tmp_path: Path) -> None:
                 environment=build_options.environment,
                 user_pyodide_version=build_options.pyodide_version,
             )
+            env["CIBUILDWHEEL_BUILD_IDENTIFIER"] = config.identifier
             pip_version = get_pip_version(env)
             # The Pyodide command line runner mounts all directories in the host
             # filesystem into the Pyodide file system, except for the custom

cibuildwheel/platforms/windows.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import dataclasses
 import json
 import os
@@ -5,7 +7,6 @@ import platform as platform_module
 import shutil
 import subprocess
 import textwrap
-from collections.abc import MutableMapping, Sequence, Set
 from functools import cache
 from pathlib import Path
 from typing import assert_never
@@ -15,15 +16,12 @@ from filelock import FileLock
 from cibuildwheel import errors
 from cibuildwheel.architecture import Architecture
 from cibuildwheel.audit import run_audit
-from cibuildwheel.environment import ParsedEnvironment
 from cibuildwheel.frontend import (
     BuildFrontendName,
     get_build_frontend_extra_flags,
     prepare_config_settings,
 )
 from cibuildwheel.logger import log
-from cibuildwheel.options import Options
-from cibuildwheel.selector import BuildSelector
 from cibuildwheel.util import resources
 from cibuildwheel.util.cmd import call, shell
 from cibuildwheel.util.file import (
@@ -32,11 +30,20 @@ from cibuildwheel.util.file import (
     download,
     extract_zip,
     move_file,
+    remove_on_error,
 )
 from cibuildwheel.util.helpers import prepare_command, unwrap
 from cibuildwheel.util.packaging import find_compatible_wheel, get_pip_version
 from cibuildwheel.venv import constraint_flags, find_uv, target_marker_env, virtualenv
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import MutableMapping, Sequence, Set
+
+    from cibuildwheel.environment import ParsedEnvironment
+    from cibuildwheel.options import Options
+    from cibuildwheel.selector import BuildSelector
+
 
 def get_nuget_args(
     version: str, arch: str, free_threaded: bool, output_directory: Path
@@ -67,6 +74,7 @@ class PythonConfiguration:
     version: str
     identifier: str
     url: str | None = None
+    sha256: str = ""
 
     @property
     def arch(self) -> str:
@@ -105,7 +113,8 @@ def _ensure_nuget() -> Path:
     nuget = CIBW_CACHE_PATH / "nuget.exe"
     with FileLock(str(nuget) + ".lock"):
         if not nuget.exists():
-            download("https://dist.nuget.org/win-x86-commandline/latest/nuget.exe", nuget)
+            with remove_on_error(nuget):
+                download("https://dist.nuget.org/win-x86-commandline/latest/nuget.exe", nuget)
     return nuget
 
 
@@ -121,11 +130,12 @@ def install_cpython(configuration: PythonConfiguration, arch: str | None = None)
     with FileLock(str(base_output_dir) + f"-{version}{free_threaded_str}-{arch}.lock"):
         if not installation_path.exists():
             nuget = _ensure_nuget()
-            call(nuget, "install", *nuget_args)
+            with remove_on_error(installation_path.parent):
+                call(nuget, "install", *nuget_args)
     return installation_path / "python.exe"
 
 
-def install_pypy(tmp: Path, arch: str, url: str) -> Path:
+def install_pypy(tmp: Path, arch: str, url: str, sha256: str) -> Path:
     assert arch == "64"
     assert "win64" in url
     # Inside the PyPy zip file is a directory with the same name
@@ -136,13 +146,14 @@ def install_pypy(tmp: Path, arch: str, url: str) -> Path:
     with FileLock(str(installation_path) + ".lock"):
         if not installation_path.exists():
             pypy_zip = tmp / 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)
+            download(url, pypy_zip, sha256=sha256)
+            with remove_on_error(installation_path):
+                # Extract to the parent directory because the zip file still contains a directory
+                extract_zip(pypy_zip, installation_path.parent)
     return installation_path / "python.exe"
 
 
-def install_graalpy(tmp: Path, url: str) -> Path:
+def install_graalpy(tmp: Path, url: str, sha256: str) -> Path:
     zip_filename = url.rsplit("/", 1)[-1]
     extension = ".zip"
     assert zip_filename.endswith(extension)
@@ -150,9 +161,10 @@ def install_graalpy(tmp: Path, url: str) -> Path:
     with FileLock(str(installation_path) + ".lock"):
         if not installation_path.exists():
             graalpy_zip = tmp / zip_filename
-            download(url, graalpy_zip)
-            # Extract to the parent directory because the zip file still contains a directory
-            extract_zip(graalpy_zip, installation_path.parent)
+            download(url, graalpy_zip, sha256=sha256)
+            with remove_on_error(installation_path):
+                # Extract to the parent directory because the zip file still contains a directory
+                extract_zip(graalpy_zip, installation_path.parent)
     return installation_path / "bin" / "graalpy.exe"
 
 
@@ -266,9 +278,14 @@ def setup_python(
             base_python = install_cpython(python_configuration, arch=native_arch)
     elif implementation_id.startswith("pp"):
         assert python_configuration.url is not None
-        base_python = install_pypy(tmp, python_configuration.arch, python_configuration.url)
+        assert python_configuration.sha256
+        base_python = install_pypy(
+            tmp, python_configuration.arch, python_configuration.url, python_configuration.sha256
+        )
     elif implementation_id.startswith("gp"):
-        base_python = install_graalpy(tmp, python_configuration.url or "")
+        assert python_configuration.url is not None
+        assert python_configuration.sha256
+        base_python = install_graalpy(tmp, python_configuration.url, python_configuration.sha256)
     else:
         msg = "Unknown Python implementation"
         raise ValueError(msg)
@@ -460,6 +477,7 @@ def build(options: Options, tmp_path: Path) -> None:
                 build_options.environment,
                 build_frontend.name,
             )
+            env["CIBUILDWHEEL_BUILD_IDENTIFIER"] = config.identifier
             pip_version = None if use_uv else get_pip_version(env)
 
             compatible_wheel = find_compatible_wheel(built_wheels, config.identifier)

cibuildwheel/projectfiles.py

@@ -1,11 +1,16 @@
+from __future__ import annotations
+
 import ast
 import configparser
 import contextlib
-from pathlib import Path
-from typing import Any
 
 import dependency_groups
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from pathlib import Path
+    from typing import Any
+
 
 def get_parent(node: ast.AST | None, depth: int = 1) -> ast.AST | None:
     for _ in range(depth):

cibuildwheel/resources/android/_cross_venv.py

@@ -14,6 +14,9 @@ def initialize() -> None:
     if not (host_triplet := os.environ.get("CIBW_HOST_TRIPLET")):
         return
 
+    # Pre-import any modules which would fail to import after the monkey-patching.
+    import ctypes  # noqa: F401, PLC0415 - uses get_config_var("LDLIBRARY")
+
     # os ######################################################################
     def cross_os_uname() -> os.uname_result:
         return os.uname_result(

cibuildwheel/resources/android/fortran_shim.py

@@ -0,0 +1,121 @@
+# This file intentionally has no hashbang line in the source: cibuildwheel will add it
+# above this comment when the file is deployed.
+
+import os
+import re
+import shutil
+import sys
+from pathlib import Path
+from tempfile import gettempdir
+
+from filelock import FileLock
+
+from cibuildwheel.util.file import CIBW_CACHE_PATH, download
+
+# In the future we might pick a different Flang release depending on the NDK version,
+# but so far all Python versions use the same NDK version, so there's no need.
+RELEASE_URL = "https://github.com/termux/ndk-toolchain-clang-with-flang/releases/download"
+RELEASE_VERSION = "r27c"
+ARCHS = ["aarch64", "x86_64"]
+
+# The compiler is built for Linux x86_64, so we use Docker on macOS.
+DOCKER_IMAGE = "debian:trixie-slim"
+
+
+def main() -> None:
+    cache_dir = CIBW_CACHE_PATH / f"flang-android-{RELEASE_VERSION}"
+    with FileLock(f"{cache_dir}.lock"):
+        if not cache_dir.exists():
+            download_flang(cache_dir)
+
+    run_flang(cache_dir)
+
+
+def download_flang(cache_dir: Path) -> None:
+    tmp_dir = Path(f"{cache_dir}.tmp")
+    if tmp_dir.exists():
+        shutil.rmtree(tmp_dir)
+    tmp_dir.mkdir(parents=True)
+
+    for archive_name in [f"package-flang-{arch}.tar.bz2" for arch in ARCHS] + [
+        "package-flang-host.tar.bz2",
+        "package-install.tar.bz2",
+    ]:
+        archive_path = tmp_dir / archive_name
+        download(f"{RELEASE_URL}/{RELEASE_VERSION}/{archive_name}", archive_path)
+        shutil.unpack_archive(archive_path, tmp_dir)
+        archive_path.unlink()
+
+    # Merge the extracted trees together, along with the necessary parts of the NDK. Based on
+    # https://github.com/kivy/python-for-android/blob/develop/pythonforandroid/recipes/fortran/__init__.py.
+    flang_toolchain = tmp_dir / "toolchain"
+    (tmp_dir / "out/install/linux-x86/clang-dev").rename(flang_toolchain)
+
+    ndk_toolchain = Path(os.environ["CC"]).parents[1]
+    if (clang_ver_flang := clang_ver(flang_toolchain)) != (
+        clang_ver_ndk := clang_ver(ndk_toolchain)
+    ):
+        msg = f"Flang uses Clang {clang_ver_flang}, but NDK uses Clang {clang_ver_ndk}"
+        raise ValueError(msg)
+
+    clang_lib_path = f"lib/clang/{clang_ver_ndk}/lib"
+    shutil.rmtree(flang_toolchain / clang_lib_path)
+
+    for src, dst in [
+        (f"{tmp_dir}/build-{arch}-install", f"sysroot/usr/lib/{arch}-linux-android")
+        for arch in ARCHS
+    ] + [
+        (f"{tmp_dir}/build-host-install", ""),
+        (f"{ndk_toolchain}/{clang_lib_path}", clang_lib_path),
+        (f"{ndk_toolchain}/sysroot", "sysroot"),
+    ]:
+        shutil.copytree(src, flang_toolchain / dst, symlinks=True, dirs_exist_ok=True)
+
+    flang_toolchain.rename(cache_dir)
+    shutil.rmtree(tmp_dir)
+
+
+def clang_ver(toolchain: Path) -> str:
+    versions = [p.name for p in (toolchain / "lib/clang").iterdir()]
+    assert len(versions) == 1
+    return versions[0]
+
+
+def run_flang(cache_dir: Path) -> None:
+    match = re.fullmatch(r".+/(.+)-clang", os.environ["CC"])
+    assert match is not None
+    target = match[1]
+
+    # In a future Flang version the executable name will change to "flang"
+    # (https://blog.llvm.org/posts/2025-03-11-flang-new/).
+    flang_args = [f"{cache_dir}/bin/flang-new", f"--target={target}", *sys.argv[1:]]
+
+    if sys.platform == "linux":
+        args = flang_args
+    elif sys.platform == "darwin":
+        args = ["docker", "run", "--rm", "--platform", "linux/amd64"]
+        # Docker on macOS only allows certain directories to be mounted as volumes
+        # by default, but they include all the locations we're likely to need.
+        for path in [
+            # Location of CIBW_CACHE_PATH (containing the Fortran compiler), and
+            # probably the project directory.
+            Path.home(),
+            # Temporary directories created by build backends and cibuildwheel itself.
+            # This is controlled by the TMPDIR environment variable, which is set to
+            # an unpredictable subdirectory of /var/folders. /var is itself a symlink
+            # to /private/var.
+            Path(gettempdir()),
+            Path(gettempdir()).resolve(),
+        ]:
+            args += ["-v", f"{path}:{path}"]
+        args += ["--workdir", str(Path.cwd())]
+        args += ["--entrypoint", flang_args[0], DOCKER_IMAGE, *flang_args[1:]]
+    else:
+        msg = f"unknown platform: {sys.platform}"
+        raise ValueError(msg)
+
+    os.execvp(args[0], args)
+
+
+if __name__ == "__main__":
+    main()

cibuildwheel/resources/build-platforms.toml

@@ -143,43 +143,43 @@ python_configurations = [
 
 [macos]
 python_configurations = [
-  { identifier = "cp39-macosx_x86_64", version = "3.9", url = "https://www.python.org/ftp/python/3.9.13/python-3.9.13-macos11.pkg" },
-  { identifier = "cp39-macosx_arm64", version = "3.9", url = "https://www.python.org/ftp/python/3.9.13/python-3.9.13-macos11.pkg" },
-  { identifier = "cp39-macosx_universal2", version = "3.9", url = "https://www.python.org/ftp/python/3.9.13/python-3.9.13-macos11.pkg" },
-  { identifier = "cp310-macosx_x86_64", version = "3.10", url = "https://www.python.org/ftp/python/3.10.11/python-3.10.11-macos11.pkg" },
-  { identifier = "cp310-macosx_arm64", version = "3.10", url = "https://www.python.org/ftp/python/3.10.11/python-3.10.11-macos11.pkg" },
-  { identifier = "cp310-macosx_universal2", version = "3.10", url = "https://www.python.org/ftp/python/3.10.11/python-3.10.11-macos11.pkg" },
-  { identifier = "cp311-macosx_x86_64", version = "3.11", url = "https://www.python.org/ftp/python/3.11.9/python-3.11.9-macos11.pkg" },
-  { identifier = "cp311-macosx_arm64", version = "3.11", url = "https://www.python.org/ftp/python/3.11.9/python-3.11.9-macos11.pkg" },
-  { identifier = "cp311-macosx_universal2", version = "3.11", url = "https://www.python.org/ftp/python/3.11.9/python-3.11.9-macos11.pkg" },
-  { identifier = "cp312-macosx_x86_64", version = "3.12", url = "https://www.python.org/ftp/python/3.12.10/python-3.12.10-macos11.pkg" },
-  { identifier = "cp312-macosx_arm64", version = "3.12", url = "https://www.python.org/ftp/python/3.12.10/python-3.12.10-macos11.pkg" },
-  { identifier = "cp312-macosx_universal2", version = "3.12", url = "https://www.python.org/ftp/python/3.12.10/python-3.12.10-macos11.pkg" },
-  { identifier = "cp313-macosx_x86_64", version = "3.13", url = "https://www.python.org/ftp/python/3.13.13/python-3.13.13-macos11.pkg" },
-  { identifier = "cp313-macosx_arm64", version = "3.13", url = "https://www.python.org/ftp/python/3.13.13/python-3.13.13-macos11.pkg" },
-  { identifier = "cp313-macosx_universal2", version = "3.13", url = "https://www.python.org/ftp/python/3.13.13/python-3.13.13-macos11.pkg" },
-  { identifier = "cp314-macosx_x86_64", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg" },
-  { identifier = "cp314-macosx_arm64", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg" },
-  { identifier = "cp314-macosx_universal2", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg" },
-  { identifier = "cp314t-macosx_x86_64", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg" },
-  { identifier = "cp314t-macosx_arm64", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg" },
-  { identifier = "cp314t-macosx_universal2", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg" },
-  { identifier = "cp315-macosx_x86_64", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b1-macos11.pkg" },
-  { identifier = "cp315-macosx_arm64", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b1-macos11.pkg" },
-  { identifier = "cp315-macosx_universal2", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b1-macos11.pkg" },
-  { identifier = "cp315t-macosx_x86_64", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b1-macos11.pkg" },
-  { identifier = "cp315t-macosx_arm64", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b1-macos11.pkg" },
-  { identifier = "cp315t-macosx_universal2", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b1-macos11.pkg" },
-  { identifier = "pp39-macosx_x86_64", version = "3.9", url = "https://downloads.python.org/pypy/pypy3.9-v7.3.16-macos_x86_64.tar.bz2" },
-  { identifier = "pp39-macosx_arm64", version = "3.9", url = "https://downloads.python.org/pypy/pypy3.9-v7.3.16-macos_arm64.tar.bz2" },
-  { identifier = "pp310-macosx_x86_64", version = "3.10", url = "https://downloads.python.org/pypy/pypy3.10-v7.3.19-macos_x86_64.tar.bz2" },
-  { identifier = "pp310-macosx_arm64", version = "3.10", url = "https://downloads.python.org/pypy/pypy3.10-v7.3.19-macos_arm64.tar.bz2" },
-  { identifier = "pp311-macosx_x86_64", version = "3.11", url = "https://downloads.python.org/pypy/pypy3.11-v7.3.22-macos_x86_64.tar.bz2" },
-  { identifier = "pp311-macosx_arm64", version = "3.11", url = "https://downloads.python.org/pypy/pypy3.11-v7.3.22-macos_arm64.tar.bz2" },
-  { identifier = "gp311_242-macosx_x86_64", version = "3.11", url = "https://github.com/oracle/graalpython/releases/download/graal-24.2.2/graalpy-24.2.2-macos-amd64.tar.gz" },
-  { identifier = "gp311_242-macosx_arm64", version = "3.11", url = "https://github.com/oracle/graalpython/releases/download/graal-24.2.2/graalpy-24.2.2-macos-aarch64.tar.gz" },
-  { identifier = "gp312_250-macosx_x86_64", version = "3.12", url = "https://github.com/oracle/graalpython/releases/download/graal-25.0.1/graalpy-25.0.1-macos-amd64.tar.gz" },
-  { identifier = "gp312_250-macosx_arm64", version = "3.12", url = "https://github.com/oracle/graalpython/releases/download/graal-25.0.2/graalpy-25.0.2-macos-aarch64.tar.gz" },
+  { identifier = "cp39-macosx_x86_64", version = "3.9", url = "https://www.python.org/ftp/python/3.9.13/python-3.9.13-macos11.pkg", sha256 = "351fe18f4fb03be7afac5e4012fc0a51345f43202af43ef620cf1eee5ee36578" },
+  { identifier = "cp39-macosx_arm64", version = "3.9", url = "https://www.python.org/ftp/python/3.9.13/python-3.9.13-macos11.pkg", sha256 = "351fe18f4fb03be7afac5e4012fc0a51345f43202af43ef620cf1eee5ee36578" },
+  { identifier = "cp39-macosx_universal2", version = "3.9", url = "https://www.python.org/ftp/python/3.9.13/python-3.9.13-macos11.pkg", sha256 = "351fe18f4fb03be7afac5e4012fc0a51345f43202af43ef620cf1eee5ee36578" },
+  { identifier = "cp310-macosx_x86_64", version = "3.10", url = "https://www.python.org/ftp/python/3.10.11/python-3.10.11-macos11.pkg", sha256 = "767ed35ad688d28ea4494081ae96408a0318d0d5bb9ca0139d74d6247b231cfc" },
+  { identifier = "cp310-macosx_arm64", version = "3.10", url = "https://www.python.org/ftp/python/3.10.11/python-3.10.11-macos11.pkg", sha256 = "767ed35ad688d28ea4494081ae96408a0318d0d5bb9ca0139d74d6247b231cfc" },
+  { identifier = "cp310-macosx_universal2", version = "3.10", url = "https://www.python.org/ftp/python/3.10.11/python-3.10.11-macos11.pkg", sha256 = "767ed35ad688d28ea4494081ae96408a0318d0d5bb9ca0139d74d6247b231cfc" },
+  { identifier = "cp311-macosx_x86_64", version = "3.11", url = "https://www.python.org/ftp/python/3.11.9/python-3.11.9-macos11.pkg", sha256 = "b6cfdee2571ca56ee895043ca1e7110fb78a878cee3eb0c21accb2de34d24b55" },
+  { identifier = "cp311-macosx_arm64", version = "3.11", url = "https://www.python.org/ftp/python/3.11.9/python-3.11.9-macos11.pkg", sha256 = "b6cfdee2571ca56ee895043ca1e7110fb78a878cee3eb0c21accb2de34d24b55" },
+  { identifier = "cp311-macosx_universal2", version = "3.11", url = "https://www.python.org/ftp/python/3.11.9/python-3.11.9-macos11.pkg", sha256 = "b6cfdee2571ca56ee895043ca1e7110fb78a878cee3eb0c21accb2de34d24b55" },
+  { identifier = "cp312-macosx_x86_64", version = "3.12", url = "https://www.python.org/ftp/python/3.12.10/python-3.12.10-macos11.pkg", sha256 = "8373e58da4ea146b3eb1c1f9834f19a319440b6b679b06050b1f9ee3237aa8e4" },
+  { identifier = "cp312-macosx_arm64", version = "3.12", url = "https://www.python.org/ftp/python/3.12.10/python-3.12.10-macos11.pkg", sha256 = "8373e58da4ea146b3eb1c1f9834f19a319440b6b679b06050b1f9ee3237aa8e4" },
+  { identifier = "cp312-macosx_universal2", version = "3.12", url = "https://www.python.org/ftp/python/3.12.10/python-3.12.10-macos11.pkg", sha256 = "8373e58da4ea146b3eb1c1f9834f19a319440b6b679b06050b1f9ee3237aa8e4" },
+  { identifier = "cp313-macosx_x86_64", version = "3.13", url = "https://www.python.org/ftp/python/3.13.13/python-3.13.13-macos11.pkg", sha256 = "a909cb655af5db67d5a90b3603437a1d58bec3446d624e4034e278ac62023cc9" },
+  { identifier = "cp313-macosx_arm64", version = "3.13", url = "https://www.python.org/ftp/python/3.13.13/python-3.13.13-macos11.pkg", sha256 = "a909cb655af5db67d5a90b3603437a1d58bec3446d624e4034e278ac62023cc9" },
+  { identifier = "cp313-macosx_universal2", version = "3.13", url = "https://www.python.org/ftp/python/3.13.13/python-3.13.13-macos11.pkg", sha256 = "a909cb655af5db67d5a90b3603437a1d58bec3446d624e4034e278ac62023cc9" },
+  { identifier = "cp314-macosx_x86_64", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg", sha256 = "b28a8dc33c456dd06c97024697d63ca916cfb494594c06fa3e4ef4d41fa82335" },
+  { identifier = "cp314-macosx_arm64", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg", sha256 = "b28a8dc33c456dd06c97024697d63ca916cfb494594c06fa3e4ef4d41fa82335" },
+  { identifier = "cp314-macosx_universal2", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg", sha256 = "b28a8dc33c456dd06c97024697d63ca916cfb494594c06fa3e4ef4d41fa82335" },
+  { identifier = "cp314t-macosx_x86_64", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg", sha256 = "b28a8dc33c456dd06c97024697d63ca916cfb494594c06fa3e4ef4d41fa82335" },
+  { identifier = "cp314t-macosx_arm64", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg", sha256 = "b28a8dc33c456dd06c97024697d63ca916cfb494594c06fa3e4ef4d41fa82335" },
+  { identifier = "cp314t-macosx_universal2", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-macos11.pkg", sha256 = "b28a8dc33c456dd06c97024697d63ca916cfb494594c06fa3e4ef4d41fa82335" },
+  { identifier = "cp315-macosx_x86_64", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b2-macos11.pkg", sha256 = "29b5c95f255f846f77e1c119146836445f929de1392a3ae9ef24f559e1345418" },
+  { identifier = "cp315-macosx_arm64", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b2-macos11.pkg", sha256 = "29b5c95f255f846f77e1c119146836445f929de1392a3ae9ef24f559e1345418" },
+  { identifier = "cp315-macosx_universal2", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b2-macos11.pkg", sha256 = "29b5c95f255f846f77e1c119146836445f929de1392a3ae9ef24f559e1345418" },
+  { identifier = "cp315t-macosx_x86_64", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b2-macos11.pkg", sha256 = "29b5c95f255f846f77e1c119146836445f929de1392a3ae9ef24f559e1345418" },
+  { identifier = "cp315t-macosx_arm64", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b2-macos11.pkg", sha256 = "29b5c95f255f846f77e1c119146836445f929de1392a3ae9ef24f559e1345418" },
+  { identifier = "cp315t-macosx_universal2", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b2-macos11.pkg", sha256 = "29b5c95f255f846f77e1c119146836445f929de1392a3ae9ef24f559e1345418" },
+  { identifier = "pp39-macosx_x86_64", version = "3.9", url = "https://downloads.python.org/pypy/pypy3.9-v7.3.16-macos_x86_64.tar.bz2", sha256 = "fda015431621e7e5aa16359d114f2c45a77ed936992c1efff86302e768a6b21c" },
+  { identifier = "pp39-macosx_arm64", version = "3.9", url = "https://downloads.python.org/pypy/pypy3.9-v7.3.16-macos_arm64.tar.bz2", sha256 = "88f824e7a2d676440d09bc90fc959ae0fd3557d7e2f14bfbbe53d41d159a47fe" },
+  { identifier = "pp310-macosx_x86_64", version = "3.10", url = "https://downloads.python.org/pypy/pypy3.10-v7.3.19-macos_x86_64.tar.bz2", sha256 = "2c5e5c2a33ac882551d7f28b98d19d486b8995aa50824a73b4edcc6aeec35c63" },
+  { identifier = "pp310-macosx_arm64", version = "3.10", url = "https://downloads.python.org/pypy/pypy3.10-v7.3.19-macos_arm64.tar.bz2", sha256 = "3db8a03fc496164801646844d7f3b12baa0adb3ad9a0b7cb124521bc2e168a36" },
+  { identifier = "pp311-macosx_x86_64", version = "3.11", url = "https://downloads.python.org/pypy/pypy3.11-v7.3.23-macos_x86_64.tar.bz2", sha256 = "c95363c4e87235d11a6cec8128239c291b1eb67a752778fbcfe029a71da82b5e" },
+  { identifier = "pp311-macosx_arm64", version = "3.11", url = "https://downloads.python.org/pypy/pypy3.11-v7.3.23-macos_arm64.tar.bz2", sha256 = "4747b3aceba4c1c6104cddc0fe5ea302101d32955f0957347b9ecc4fbd7aed05" },
+  { identifier = "gp311_242-macosx_x86_64", version = "3.11", url = "https://github.com/oracle/graalpython/releases/download/graal-24.2.2/graalpy-24.2.2-macos-amd64.tar.gz", sha256 = "2f4d5e7dbdf90e38778dfcb8ca3e1ec7eee257ef726b1937d5bc91b54cdddf9b" },
+  { identifier = "gp311_242-macosx_arm64", version = "3.11", url = "https://github.com/oracle/graalpython/releases/download/graal-24.2.2/graalpy-24.2.2-macos-aarch64.tar.gz", sha256 = "f4a2ae01bae0fa53ec0d19f86d73c6dcc2a162d245552030183b84bfdd8f7635" },
+  { identifier = "gp312_250-macosx_x86_64", version = "3.12", url = "https://github.com/oracle/graalpython/releases/download/graal-25.0.1/graalpy-25.0.1-macos-amd64.tar.gz", sha256 = "10b0721d52397f0cc85f038900318da2203711cbcfae7899e3faed49d3dc6221" },
+  { identifier = "gp312_250-macosx_arm64", version = "3.12", url = "https://github.com/oracle/graalpython/releases/download/graal-25.0.3/graalpy-25.0.3-macos-aarch64.tar.gz", sha256 = "387d9f5b376860842bea4d55aae5820974f3f3b68fc36c77ae863a061a888857" },
 ]
 
 [windows]
@@ -198,10 +198,10 @@ python_configurations = [
   { identifier = "cp314t-win32", version = "3.14.5" },
   { identifier = "cp314-win_amd64", version = "3.14.5" },
   { identifier = "cp314t-win_amd64", version = "3.14.5" },
-  { identifier = "cp315-win32", version = "3.15.0-b1" },
-  { identifier = "cp315t-win32", version = "3.15.0-b1" },
-  { identifier = "cp315-win_amd64", version = "3.15.0-b1" },
-  { identifier = "cp315t-win_amd64", version = "3.15.0-b1" },
+  { identifier = "cp315-win32", version = "3.15.0-b2" },
+  { identifier = "cp315t-win32", version = "3.15.0-b2" },
+  { identifier = "cp315-win_amd64", version = "3.15.0-b2" },
+  { identifier = "cp315t-win_amd64", version = "3.15.0-b2" },
   { identifier = "cp39-win_arm64", version = "3.9.10" },
   { identifier = "cp310-win_arm64", version = "3.10.11" },
   { identifier = "cp311-win_arm64", version = "3.11.9" },
@@ -209,36 +209,41 @@ python_configurations = [
   { identifier = "cp313-win_arm64", version = "3.13.13" },
   { identifier = "cp314-win_arm64", version = "3.14.5" },
   { identifier = "cp314t-win_arm64", version = "3.14.5" },
-  { identifier = "cp315-win_arm64", version = "3.15.0-b1" },
-  { identifier = "cp315t-win_arm64", version = "3.15.0-b1" },
-  { identifier = "pp39-win_amd64", version = "3.9", url = "https://downloads.python.org/pypy/pypy3.9-v7.3.16-win64.zip" },
-  { identifier = "pp310-win_amd64", version = "3.10", url = "https://downloads.python.org/pypy/pypy3.10-v7.3.19-win64.zip" },
-  { identifier = "pp311-win_amd64", version = "3.11", url = "https://downloads.python.org/pypy/pypy3.11-v7.3.22-win64.zip" },
-  { identifier = "gp311_242-win_amd64", version = "3.11", url = "https://github.com/oracle/graalpython/releases/download/graal-24.2.2/graalpy-24.2.2-windows-amd64.zip" },
-  { identifier = "gp312_250-win_amd64", version = "3.12", url = "https://github.com/oracle/graalpython/releases/download/graal-25.0.2/graalpy-25.0.2-windows-amd64.zip" },
+  { identifier = "cp315-win_arm64", version = "3.15.0-b2" },
+  { identifier = "cp315t-win_arm64", version = "3.15.0-b2" },
+  { identifier = "pp39-win_amd64", version = "3.9", url = "https://downloads.python.org/pypy/pypy3.9-v7.3.16-win64.zip", sha256 = "06ec12a5e964dc0ad33e6f380185a4d295178dce6d6df512f508e7aee00a1323" },
+  { identifier = "pp310-win_amd64", version = "3.10", url = "https://downloads.python.org/pypy/pypy3.10-v7.3.19-win64.zip", sha256 = "c0d07bba6c8fb4e5804f4a8b3f8ef07cc3d89f6ad1db42a45ffb9be60bbb7cc2" },
+  { identifier = "pp311-win_amd64", version = "3.11", url = "https://downloads.python.org/pypy/pypy3.11-v7.3.23-win64.zip", sha256 = "948b8ea58dea5b9917210fe4afd242c788fbfaba1c3f1a25e696a404f703389a" },
+  { identifier = "gp311_242-win_amd64", version = "3.11", url = "https://github.com/oracle/graalpython/releases/download/graal-24.2.2/graalpy-24.2.2-windows-amd64.zip", sha256 = "9606134284d4d95b2f9d69c3087cd3e9e488f46355b419f5e66588a3281df6a3" },
+  { identifier = "gp312_250-win_amd64", version = "3.12", url = "https://github.com/oracle/graalpython/releases/download/graal-25.0.3/graalpy-25.0.3-windows-amd64.zip", sha256 = "2ae5c42b93e08d9e106a017634a3442b272ccae6d08ace157244de0449e937d4" },
 ]
 
 [pyodide]
 python_configurations = [
-  { identifier = "cp312-pyodide_wasm32", version = "3.12", default_pyodide_version = "0.27.7", node_version = "v22" },
-  { identifier = "cp313-pyodide_wasm32", version = "3.13", default_pyodide_version = "0.29.4", node_version = "v22" },
-  { identifier = "cp314-pyodide_wasm32", version = "3.14", default_pyodide_version = "314.0.0a2", node_version = "v24" },
+  { identifier = "cp312-pyodide_wasm32", version = "3.12", default_pyodide_version = "0.27.7", node_version = "v22", sha256 = "0c2e7db42efa5d1dac38b50f8b3d659a1e3885d0a233494831b8206281307d52" },
+  { identifier = "cp313-pyodide_wasm32", version = "3.13", default_pyodide_version = "0.29.4", node_version = "v22", sha256 = "a29fc4a076408a18fc29eb4b280f80c6dddc95c19514c874c29e590d0931c02a" },
+  { identifier = "cp314-pyodide_wasm32", version = "3.14", default_pyodide_version = "314.0.0a2", node_version = "v24", sha256 = "ac7bbcdf289ab3ae25621c436b1d013099ef6bec644ad0538dae5d65552c5c95" },
 ]
 
 [android]
 python_configurations = [
-  { identifier = "cp313-android_arm64_v8a", version = "3.13", url = "https://repo.maven.apache.org/maven2/com/chaquo/python/python/3.13.13/python-3.13.13-aarch64-linux-android.tar.gz" },
-  { identifier = "cp313-android_x86_64", version = "3.13", url = "https://repo.maven.apache.org/maven2/com/chaquo/python/python/3.13.13/python-3.13.13-x86_64-linux-android.tar.gz" },
-  { identifier = "cp314-android_arm64_v8a", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-aarch64-linux-android.tar.gz" },
-  { identifier = "cp314-android_x86_64", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-x86_64-linux-android.tar.gz" },
+  { identifier = "cp313-android_arm64_v8a", version = "3.13", url = "https://repo.maven.apache.org/maven2/com/chaquo/python/python/3.13.13/python-3.13.13-aarch64-linux-android.tar.gz", sha256 = "a21250c246b36eb704be096be51e40ab24cafa3ae1d7ca4c396e6bf780cf87cf" },
+  { identifier = "cp313-android_x86_64", version = "3.13", url = "https://repo.maven.apache.org/maven2/com/chaquo/python/python/3.13.13/python-3.13.13-x86_64-linux-android.tar.gz", sha256 = "b021b76df2c8d64e41c76d18a2d91f27652356bd932c06f9076bac1b664c0e37" },
+  { identifier = "cp314-android_arm64_v8a", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-aarch64-linux-android.tar.gz", sha256 = "f008321abf837fcaec569df143283ece0e764b18d8c75763200160553f906af1" },
+  { identifier = "cp314-android_x86_64", version = "3.14", url = "https://www.python.org/ftp/python/3.14.5/python-3.14.5-x86_64-linux-android.tar.gz", sha256 = "36184e31464b2b959d92c81ded8d025834342cc080623bced282a2a9a57bd47c" },
+  { identifier = "cp315-android_arm64_v8a", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b2-aarch64-linux-android.tar.gz", sha256 = "de5e36ffc3c33b63a1ed53fe83db4dee16b003a3180ac35e5c4c203d3750e076" },
+  { identifier = "cp315-android_x86_64", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b2-x86_64-linux-android.tar.gz", sha256 = "e05ef9c142ea83b41b194b16014ffe2249d27783313c3b00b97f6c93d9a56b92" },
 ]
 
 [ios]
 python_configurations = [
-  { identifier = "cp313-ios_arm64_iphoneos", version = "3.13", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.13-b13/Python-3.13-iOS-support.b13.tar.gz" },
-  { identifier = "cp313-ios_x86_64_iphonesimulator", version = "3.13", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.13-b13/Python-3.13-iOS-support.b13.tar.gz" },
-  { identifier = "cp313-ios_arm64_iphonesimulator", version = "3.13", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.13-b13/Python-3.13-iOS-support.b13.tar.gz" },
-  { identifier = "cp314-ios_arm64_iphoneos", version = "3.14", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.14-b9/Python-3.14-iOS-support.b9.tar.gz" },
-  { identifier = "cp314-ios_x86_64_iphonesimulator", version = "3.14", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.14-b9/Python-3.14-iOS-support.b9.tar.gz" },
-  { identifier = "cp314-ios_arm64_iphonesimulator", version = "3.14", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.14-b9/Python-3.14-iOS-support.b9.tar.gz" },
+  { identifier = "cp313-ios_arm64_iphoneos", version = "3.13", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.13-b13/Python-3.13-iOS-support.b13.tar.gz", sha256 = "d1f95f95137a4b91dc0cbe9b99ddfc0a78918dde883c7fbe7147074a5e715274" },
+  { identifier = "cp313-ios_x86_64_iphonesimulator", version = "3.13", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.13-b13/Python-3.13-iOS-support.b13.tar.gz", sha256 = "d1f95f95137a4b91dc0cbe9b99ddfc0a78918dde883c7fbe7147074a5e715274" },
+  { identifier = "cp313-ios_arm64_iphonesimulator", version = "3.13", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.13-b13/Python-3.13-iOS-support.b13.tar.gz", sha256 = "d1f95f95137a4b91dc0cbe9b99ddfc0a78918dde883c7fbe7147074a5e715274" },
+  { identifier = "cp314-ios_arm64_iphoneos", version = "3.14", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.14-b9/Python-3.14-iOS-support.b9.tar.gz", sha256 = "8e4123b543bf17fdae2e2c6c033434487752438431014eb12e6d833aa35927a8" },
+  { identifier = "cp314-ios_x86_64_iphonesimulator", version = "3.14", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.14-b9/Python-3.14-iOS-support.b9.tar.gz", sha256 = "8e4123b543bf17fdae2e2c6c033434487752438431014eb12e6d833aa35927a8" },
+  { identifier = "cp314-ios_arm64_iphonesimulator", version = "3.14", url = "https://github.com/beeware/Python-Apple-support/releases/download/3.14-b9/Python-3.14-iOS-support.b9.tar.gz", sha256 = "8e4123b543bf17fdae2e2c6c033434487752438431014eb12e6d833aa35927a8" },
+  { identifier = "cp315-ios_arm64_iphoneos", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b2-iOS-XCframework.tar.gz", sha256 = "fd6b6fb8f82cf44622d28ea53b8197c89fb06505557d29d4d7a47f9386c1c896" },
+  { identifier = "cp315-ios_x86_64_iphonesimulator", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b2-iOS-XCframework.tar.gz", sha256 = "fd6b6fb8f82cf44622d28ea53b8197c89fb06505557d29d4d7a47f9386c1c896" },
+  { identifier = "cp315-ios_arm64_iphonesimulator", version = "3.15", url = "https://www.python.org/ftp/python/3.15.0/python-3.15.0b2-iOS-XCframework.tar.gz", sha256 = "fd6b6fb8f82cf44622d28ea53b8197c89fb06505557d29d4d7a47f9386c1c896" },
 ]

cibuildwheel/resources/cibuildwheel.schema.json

@@ -460,6 +460,34 @@
       ],
       "title": "CIBW_XBUILD_TOOLS"
     },
+    "xbuild-files": {
+      "description": "Platform-specific files in the build environment",
+      "oneOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "object",
+          "additionalProperties": false,
+          "patternProperties": {
+            ".+": {
+              "oneOf": [
+                {
+                  "type": "string"
+                },
+                {
+                  "type": "array",
+                  "items": {
+                    "type": "string"
+                  }
+                }
+              ]
+            }
+          }
+        }
+      ],
+      "title": "CIBW_XBUILD_FILES"
+    },
     "pyodide-version": {
       "type": "string",
       "description": "Specify the version of Pyodide to use",
@@ -679,6 +707,9 @@
               "xbuild-tools": {
                 "$ref": "#/$defs/inherit"
               },
+              "xbuild-files": {
+                "$ref": "#/$defs/inherit"
+              },
               "before-test": {
                 "$ref": "#/$defs/inherit"
               },
@@ -807,6 +838,9 @@
           "xbuild-tools": {
             "$ref": "#/properties/xbuild-tools"
           },
+          "xbuild-files": {
+            "$ref": "#/properties/xbuild-files"
+          },
           "pyodide-version": {
             "$ref": "#/properties/pyodide-version"
           },
@@ -931,6 +965,9 @@
         "xbuild-tools": {
           "$ref": "#/properties/xbuild-tools"
         },
+        "xbuild-files": {
+          "$ref": "#/properties/xbuild-files"
+        },
         "pyodide-version": {
           "$ref": "#/properties/pyodide-version"
         },
@@ -1013,11 +1050,27 @@
         "xbuild-tools": {
           "$ref": "#/properties/xbuild-tools"
         },
+        "xbuild-files": {
+          "$ref": "#/properties/xbuild-files"
+        },
         "pyodide-version": {
           "$ref": "#/properties/pyodide-version"
         },
         "repair-wheel-command": {
-          "$ref": "#/properties/repair-wheel-command"
+          "description": "Execute a shell command to repair each built wheel.",
+          "oneOf": [
+            {
+              "type": "string"
+            },
+            {
+              "type": "array",
+              "items": {
+                "type": "string"
+              }
+            }
+          ],
+          "title": "CIBW_REPAIR_WHEEL_COMMAND",
+          "default": "delvewheel repair -w {dest_dir} -v {wheel}"
         },
         "test-command": {
           "$ref": "#/properties/test-command"
@@ -1082,6 +1135,9 @@
         "xbuild-tools": {
           "$ref": "#/properties/xbuild-tools"
         },
+        "xbuild-files": {
+          "$ref": "#/properties/xbuild-files"
+        },
         "pyodide-version": {
           "$ref": "#/properties/pyodide-version"
         },
@@ -1164,6 +1220,9 @@
         "xbuild-tools": {
           "$ref": "#/properties/xbuild-tools"
         },
+        "xbuild-files": {
+          "$ref": "#/properties/xbuild-files"
+        },
         "pyodide-version": {
           "$ref": "#/properties/pyodide-version"
         },
@@ -1233,11 +1292,27 @@
         "xbuild-tools": {
           "$ref": "#/properties/xbuild-tools"
         },
+        "xbuild-files": {
+          "$ref": "#/properties/xbuild-files"
+        },
         "pyodide-version": {
           "$ref": "#/properties/pyodide-version"
         },
         "repair-wheel-command": {
-          "$ref": "#/properties/repair-wheel-command"
+          "description": "Execute a shell command to repair each built wheel.",
+          "oneOf": [
+            {
+              "type": "string"
+            },
+            {
+              "type": "array",
+              "items": {
+                "type": "string"
+              }
+            }
+          ],
+          "title": "CIBW_REPAIR_WHEEL_COMMAND",
+          "default": "auditwheel repair --ldpaths {ldpaths} -w {dest_dir} {wheel}"
         },
         "test-command": {
           "$ref": "#/properties/test-command"
@@ -1302,6 +1377,9 @@
         "xbuild-tools": {
           "$ref": "#/properties/xbuild-tools"
         },
+        "xbuild-files": {
+          "$ref": "#/properties/xbuild-files"
+        },
         "pyodide-version": {
           "$ref": "#/properties/pyodide-version"
         },

cibuildwheel/resources/constraints-pyodide312.txt

@@ -2,13 +2,13 @@
 #    nox -s update_constraints
 annotated-types==0.7.0
     # via pydantic
-auditwheel-emscripten==0.2.4
+auditwheel-emscripten==0.2.5
     # via pyodide-build
 build==1.5.0
     # via
     #   -r .nox/update_constraints/tmp/constraints-pyodide.in
     #   pyodide-build
-certifi==2026.4.22
+certifi==2026.5.20
     # via requests
 charset-normalizer==3.4.7
     # via requests
@@ -17,13 +17,13 @@ click==8.1.8
     #   -r .nox/update_constraints/tmp/constraints-pyodide.in
     #   pyodide-build
     #   pyodide-cli
-distlib==0.4.0
+distlib==0.4.1
     # via virtualenv
-filelock==3.29.0
+filelock==3.29.1
     # via
     #   python-discovery
     #   virtualenv
-idna==3.15
+idna==3.18
     # via requests
 leb128==1.0.9
     # via auditwheel-emscripten
@@ -37,9 +37,9 @@ packaging==26.2
     #   build
     #   pyodide-build
     #   wheel
-pip==26.1.1
+pip==26.1.2
     # via -r .nox/update_constraints/tmp/constraints-pyodide.in
-platformdirs==4.9.6
+platformdirs==4.10.0
     # via
     #   pyodide-build
     #   python-discovery
@@ -52,7 +52,7 @@ pydantic-core==2.46.4
     # via pydantic
 pygments==2.20.0
     # via rich
-pyodide-build==0.34.3
+pyodide-build==0.34.4
     # via -r .nox/update_constraints/tmp/constraints-pyodide.in
 pyodide-cli==0.5.0
     # via
@@ -62,9 +62,9 @@ pyodide-lock==0.1.3
     # via pyodide-build
 pyproject-hooks==1.2.0
     # via build
-python-discovery==1.3.1
+python-discovery==1.4.0
     # via virtualenv
-requests==2.34.1
+requests==2.34.2
     # via pyodide-build
 rich==15.0.0
     # via
@@ -81,7 +81,7 @@ typing-inspection==0.4.2
     # via pydantic
 urllib3==2.7.0
     # via requests
-virtualenv==21.3.3
+virtualenv==21.4.2
     # via
     #   build
     #   pyodide-build

cibuildwheel/resources/constraints-pyodide313.txt

@@ -2,13 +2,13 @@
 #    nox -s update_constraints
 annotated-types==0.7.0
     # via pydantic
-auditwheel-emscripten==0.2.4
+auditwheel-emscripten==0.2.5
     # via pyodide-build
 build==1.5.0
     # via
     #   -r .nox/update_constraints/tmp/constraints-pyodide.in
     #   pyodide-build
-certifi==2026.4.22
+certifi==2026.5.20
     # via requests
 charset-normalizer==3.4.7
     # via requests
@@ -17,13 +17,13 @@ click==8.1.8
     #   -r .nox/update_constraints/tmp/constraints-pyodide.in
     #   pyodide-build
     #   pyodide-cli
-distlib==0.4.0
+distlib==0.4.1
     # via virtualenv
-filelock==3.29.0
+filelock==3.29.1
     # via
     #   python-discovery
     #   virtualenv
-idna==3.15
+idna==3.18
     # via requests
 leb128==1.0.9
     # via auditwheel-emscripten
@@ -37,9 +37,9 @@ packaging==26.2
     #   build
     #   pyodide-build
     #   wheel
-pip==26.1.1
+pip==26.1.2
     # via -r .nox/update_constraints/tmp/constraints-pyodide.in
-platformdirs==4.9.6
+platformdirs==4.10.0
     # via
     #   pyodide-build
     #   python-discovery
@@ -52,7 +52,7 @@ pydantic-core==2.46.4
     # via pydantic
 pygments==2.20.0
     # via rich
-pyodide-build==0.34.3
+pyodide-build==0.34.4
     # via -r .nox/update_constraints/tmp/constraints-pyodide.in
 pyodide-cli==0.5.0
     # via
@@ -62,9 +62,9 @@ pyodide-lock==0.1.3
     # via pyodide-build
 pyproject-hooks==1.2.0
     # via build
-python-discovery==1.3.1
+python-discovery==1.4.0
     # via virtualenv
-requests==2.34.1
+requests==2.34.2
     # via pyodide-build
 rich==15.0.0
     # via
@@ -81,7 +81,7 @@ typing-inspection==0.4.2
     # via pydantic
 urllib3==2.7.0
     # via requests
-virtualenv==21.3.3
+virtualenv==21.4.2
     # via
     #   build
     #   pyodide-build

cibuildwheel/resources/constraints-pyodide314.txt

@@ -2,13 +2,13 @@
 #    nox -s update_constraints
 annotated-types==0.7.0
     # via pydantic
-auditwheel-emscripten==0.2.4
+auditwheel-emscripten==0.2.5
     # via pyodide-build
 build==1.5.0
     # via
     #   -r .nox/update_constraints/tmp/constraints-pyodide.in
     #   pyodide-build
-certifi==2026.4.22
+certifi==2026.5.20
     # via requests
 charset-normalizer==3.4.7
     # via requests
@@ -17,13 +17,13 @@ click==8.1.8
     #   -r .nox/update_constraints/tmp/constraints-pyodide.in
     #   pyodide-build
     #   pyodide-cli
-distlib==0.4.0
+distlib==0.4.1
     # via virtualenv
-filelock==3.29.0
+filelock==3.29.1
     # via
     #   python-discovery
     #   virtualenv
-idna==3.15
+idna==3.18
     # via requests
 leb128==1.0.9
     # via auditwheel-emscripten
@@ -37,9 +37,9 @@ packaging==26.2
     #   build
     #   pyodide-build
     #   wheel
-pip==26.1.1
+pip==26.1.2
     # via -r .nox/update_constraints/tmp/constraints-pyodide.in
-platformdirs==4.9.6
+platformdirs==4.10.0
     # via
     #   pyodide-build
     #   python-discovery
@@ -52,7 +52,7 @@ pydantic-core==2.46.4
     # via pydantic
 pygments==2.20.0
     # via rich
-pyodide-build==0.34.3
+pyodide-build==0.34.4
     # via -r .nox/update_constraints/tmp/constraints-pyodide.in
 pyodide-cli==0.5.0
     # via
@@ -62,9 +62,9 @@ pyodide-lock==0.1.3
     # via pyodide-build
 pyproject-hooks==1.2.0
     # via build
-python-discovery==1.3.1
+python-discovery==1.4.0
     # via virtualenv
-requests==2.34.1
+requests==2.34.2
     # via pyodide-build
 rich==15.0.0
     # via
@@ -81,7 +81,7 @@ typing-inspection==0.4.2
     # via pydantic
 urllib3==2.7.0
     # via requests
-virtualenv==21.3.3
+virtualenv==21.4.2
     # via
     #   build
     #   pyodide-build

cibuildwheel/resources/constraints-python310.txt

@@ -10,27 +10,29 @@ attrs==26.1.0
     # via
     #   cattrs
     #   requests-cache
+auditwheel==6.7.0
+    # via -r cibuildwheel/resources/constraints.in
 build==1.5.0
     # via -r cibuildwheel/resources/constraints.in
 cattrs==26.1.0
     # via requests-cache
-certifi==2026.4.22
+certifi==2026.5.20
     # via requests
 charset-normalizer==3.4.7
     # via requests
 delocate==0.13.0
     # via -r cibuildwheel/resources/constraints.in
-delvewheel==1.12.1
+delvewheel==1.13.0
     # via -r cibuildwheel/resources/constraints.in
-distlib==0.4.0
+distlib==0.4.1
     # via virtualenv
 exceptiongroup==1.3.1
     # via cattrs
-filelock==3.29.0
+filelock==3.29.1
     # via
     #   python-discovery
     #   virtualenv
-idna==3.15
+idna==3.18
     # via
     #   requests
     #   url-normalize
@@ -47,28 +49,35 @@ mdurl==0.1.2
 packaging==26.2
     # via
     #   abi3audit
+    #   auditwheel
     #   build
     #   delocate
+patchelf==0.17.2.4
+    # via -r cibuildwheel/resources/constraints.in
 pefile==2024.8.26
     # via
     #   abi3audit
     #   delvewheel
-pip==26.1.1
+pip==26.1.2
     # via -r cibuildwheel/resources/constraints.in
-platformdirs==4.9.6
+pkgconf==2.5.1.post2
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.10.0
     # via
     #   python-discovery
     #   requests-cache
     #   virtualenv
-pyelftools==0.32
-    # via abi3audit
+pyelftools==0.33
+    # via
+    #   abi3audit
+    #   auditwheel
 pygments==2.20.0
     # via rich
 pyproject-hooks==1.2.0
     # via build
-python-discovery==1.3.1
+python-discovery==1.4.0
     # via virtualenv
-requests==2.34.1
+requests==2.34.2
     # via
     #   abi3audit
     #   requests-cache
@@ -90,7 +99,7 @@ urllib3==2.7.0
     # via
     #   requests
     #   requests-cache
-virtualenv==21.3.3
+virtualenv==21.4.2
     # via -r cibuildwheel/resources/constraints.in
-zipp==3.23.1
+zipp==4.1.0
     # via importlib-metadata

cibuildwheel/resources/constraints-python311.txt

@@ -10,25 +10,27 @@ attrs==26.1.0
     # via
     #   cattrs
     #   requests-cache
+auditwheel==6.7.0
+    # via -r cibuildwheel/resources/constraints.in
 build==1.5.0
     # via -r cibuildwheel/resources/constraints.in
 cattrs==26.1.0
     # via requests-cache
-certifi==2026.4.22
+certifi==2026.5.20
     # via requests
 charset-normalizer==3.4.7
     # via requests
 delocate==0.13.0
     # via -r cibuildwheel/resources/constraints.in
-delvewheel==1.12.1
+delvewheel==1.13.0
     # via -r cibuildwheel/resources/constraints.in
-distlib==0.4.0
+distlib==0.4.1
     # via virtualenv
-filelock==3.29.0
+filelock==3.29.1
     # via
     #   python-discovery
     #   virtualenv
-idna==3.15
+idna==3.18
     # via
     #   requests
     #   url-normalize
@@ -43,29 +45,36 @@ mdurl==0.1.2
 packaging==26.2
     # via
     #   abi3audit
+    #   auditwheel
     #   build
     #   delocate
+patchelf==0.17.2.4
+    # via -r cibuildwheel/resources/constraints.in
 pefile==2024.8.26
     # via
     #   abi3audit
     #   delvewheel
-pip==26.1.1; implementation_name != "graalpy" or platform_system != "Windows"
+pip==26.1.2; implementation_name != "graalpy" or platform_system != "Windows"
 pip==26.0.1; implementation_name == "graalpy" and platform_system == "Windows"
     # via -r cibuildwheel/resources/constraints.in
-platformdirs==4.9.6
+pkgconf==2.5.1.post2
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.10.0
     # via
     #   python-discovery
     #   requests-cache
     #   virtualenv
-pyelftools==0.32
-    # via abi3audit
+pyelftools==0.33
+    # via
+    #   abi3audit
+    #   auditwheel
 pygments==2.20.0
     # via rich
 pyproject-hooks==1.2.0
     # via build
-python-discovery==1.3.1
+python-discovery==1.4.0
     # via virtualenv
-requests==2.34.1
+requests==2.34.2
     # via
     #   abi3audit
     #   requests-cache
@@ -83,5 +92,5 @@ urllib3==2.7.0
     # via
     #   requests
     #   requests-cache
-virtualenv==21.3.3
+virtualenv==21.4.2
     # via -r cibuildwheel/resources/constraints.in

cibuildwheel/resources/constraints-python312.txt

@@ -10,25 +10,27 @@ attrs==26.1.0
     # via
     #   cattrs
     #   requests-cache
+auditwheel==6.7.0
+    # via -r cibuildwheel/resources/constraints.in
 build==1.5.0
     # via -r cibuildwheel/resources/constraints.in
 cattrs==26.1.0
     # via requests-cache
-certifi==2026.4.22
+certifi==2026.5.20
     # via requests
 charset-normalizer==3.4.7
     # via requests
 delocate==0.13.0
     # via -r cibuildwheel/resources/constraints.in
-delvewheel==1.12.1
+delvewheel==1.13.0
     # via -r cibuildwheel/resources/constraints.in
-distlib==0.4.0
+distlib==0.4.1
     # via virtualenv
-filelock==3.29.0
+filelock==3.29.1
     # via
     #   python-discovery
     #   virtualenv
-idna==3.15
+idna==3.18
     # via
     #   requests
     #   url-normalize
@@ -43,29 +45,36 @@ mdurl==0.1.2
 packaging==26.2
     # via
     #   abi3audit
+    #   auditwheel
     #   build
     #   delocate
+patchelf==0.17.2.4
+    # via -r cibuildwheel/resources/constraints.in
 pefile==2024.8.26
     # via
     #   abi3audit
     #   delvewheel
-pip==26.1.1; implementation_name != "graalpy" or platform_system != "Windows"
+pip==26.1.2; implementation_name != "graalpy" or platform_system != "Windows"
 pip==26.0.1; implementation_name == "graalpy" and platform_system == "Windows"
     # via -r cibuildwheel/resources/constraints.in
-platformdirs==4.9.6
+pkgconf==2.5.1.post2
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.10.0
     # via
     #   python-discovery
     #   requests-cache
     #   virtualenv
-pyelftools==0.32
-    # via abi3audit
+pyelftools==0.33
+    # via
+    #   abi3audit
+    #   auditwheel
 pygments==2.20.0
     # via rich
 pyproject-hooks==1.2.0
     # via build
-python-discovery==1.3.1
+python-discovery==1.4.0
     # via virtualenv
-requests==2.34.1
+requests==2.34.2
     # via
     #   abi3audit
     #   requests-cache
@@ -83,5 +92,5 @@ urllib3==2.7.0
     # via
     #   requests
     #   requests-cache
-virtualenv==21.3.3
+virtualenv==21.4.2
     # via -r cibuildwheel/resources/constraints.in

cibuildwheel/resources/constraints-python313.txt

@@ -10,25 +10,27 @@ attrs==26.1.0
     # via
     #   cattrs
     #   requests-cache
+auditwheel==6.7.0
+    # via -r cibuildwheel/resources/constraints.in
 build==1.5.0
     # via -r cibuildwheel/resources/constraints.in
 cattrs==26.1.0
     # via requests-cache
-certifi==2026.4.22
+certifi==2026.5.20
     # via requests
 charset-normalizer==3.4.7
     # via requests
 delocate==0.13.0
     # via -r cibuildwheel/resources/constraints.in
-delvewheel==1.12.1
+delvewheel==1.13.0
     # via -r cibuildwheel/resources/constraints.in
-distlib==0.4.0
+distlib==0.4.1
     # via virtualenv
-filelock==3.29.0
+filelock==3.29.1
     # via
     #   python-discovery
     #   virtualenv
-idna==3.15
+idna==3.18
     # via
     #   requests
     #   url-normalize
@@ -43,28 +45,35 @@ mdurl==0.1.2
 packaging==26.2
     # via
     #   abi3audit
+    #   auditwheel
     #   build
     #   delocate
+patchelf==0.17.2.4
+    # via -r cibuildwheel/resources/constraints.in
 pefile==2024.8.26
     # via
     #   abi3audit
     #   delvewheel
-pip==26.1.1
+pip==26.1.2
     # via -r cibuildwheel/resources/constraints.in
-platformdirs==4.9.6
+pkgconf==2.5.1.post2
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.10.0
     # via
     #   python-discovery
     #   requests-cache
     #   virtualenv
-pyelftools==0.32
-    # via abi3audit
+pyelftools==0.33
+    # via
+    #   abi3audit
+    #   auditwheel
 pygments==2.20.0
     # via rich
 pyproject-hooks==1.2.0
     # via build
-python-discovery==1.3.1
+python-discovery==1.4.0
     # via virtualenv
-requests==2.34.1
+requests==2.34.2
     # via
     #   abi3audit
     #   requests-cache
@@ -82,5 +91,5 @@ urllib3==2.7.0
     # via
     #   requests
     #   requests-cache
-virtualenv==21.3.3
+virtualenv==21.4.2
     # via -r cibuildwheel/resources/constraints.in

cibuildwheel/resources/constraints-python314.txt

@@ -10,25 +10,27 @@ attrs==26.1.0
     # via
     #   cattrs
     #   requests-cache
+auditwheel==6.7.0
+    # via -r cibuildwheel/resources/constraints.in
 build==1.5.0
     # via -r cibuildwheel/resources/constraints.in
 cattrs==26.1.0
     # via requests-cache
-certifi==2026.4.22
+certifi==2026.5.20
     # via requests
 charset-normalizer==3.4.7
     # via requests
 delocate==0.13.0
     # via -r cibuildwheel/resources/constraints.in
-delvewheel==1.12.1
+delvewheel==1.13.0
     # via -r cibuildwheel/resources/constraints.in
-distlib==0.4.0
+distlib==0.4.1
     # via virtualenv
-filelock==3.29.0
+filelock==3.29.1
     # via
     #   python-discovery
     #   virtualenv
-idna==3.15
+idna==3.18
     # via
     #   requests
     #   url-normalize
@@ -43,28 +45,35 @@ mdurl==0.1.2
 packaging==26.2
     # via
     #   abi3audit
+    #   auditwheel
     #   build
     #   delocate
+patchelf==0.17.2.4
+    # via -r cibuildwheel/resources/constraints.in
 pefile==2024.8.26
     # via
     #   abi3audit
     #   delvewheel
-pip==26.1.1
+pip==26.1.2
     # via -r cibuildwheel/resources/constraints.in
-platformdirs==4.9.6
+pkgconf==2.5.1.post2
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.10.0
     # via
     #   python-discovery
     #   requests-cache
     #   virtualenv
-pyelftools==0.32
-    # via abi3audit
+pyelftools==0.33
+    # via
+    #   abi3audit
+    #   auditwheel
 pygments==2.20.0
     # via rich
 pyproject-hooks==1.2.0
     # via build
-python-discovery==1.3.1
+python-discovery==1.4.0
     # via virtualenv
-requests==2.34.1
+requests==2.34.2
     # via
     #   abi3audit
     #   requests-cache
@@ -82,5 +91,5 @@ urllib3==2.7.0
     # via
     #   requests
     #   requests-cache
-virtualenv==21.3.3
+virtualenv==21.4.2
     # via -r cibuildwheel/resources/constraints.in

cibuildwheel/resources/constraints-python315.txt

@@ -10,25 +10,27 @@ attrs==26.1.0
     # via
     #   cattrs
     #   requests-cache
+auditwheel==6.7.0
+    # via -r cibuildwheel/resources/constraints.in
 build==1.5.0
     # via -r cibuildwheel/resources/constraints.in
 cattrs==26.1.0
     # via requests-cache
-certifi==2026.4.22
+certifi==2026.5.20
     # via requests
 charset-normalizer==3.4.7
     # via requests
 delocate==0.13.0
     # via -r cibuildwheel/resources/constraints.in
-delvewheel==1.12.1
+delvewheel==1.13.0
     # via -r cibuildwheel/resources/constraints.in
-distlib==0.4.0
+distlib==0.4.1
     # via virtualenv
-filelock==3.29.0
+filelock==3.29.1
     # via
     #   python-discovery
     #   virtualenv
-idna==3.15
+idna==3.18
     # via
     #   requests
     #   url-normalize
@@ -43,28 +45,35 @@ mdurl==0.1.2
 packaging==26.2
     # via
     #   abi3audit
+    #   auditwheel
     #   build
     #   delocate
+patchelf==0.17.2.4
+    # via -r cibuildwheel/resources/constraints.in
 pefile==2024.8.26
     # via
     #   abi3audit
     #   delvewheel
-pip==26.1.1
+pip==26.1.2
     # via -r cibuildwheel/resources/constraints.in
-platformdirs==4.9.6
+pkgconf==2.5.1.post2
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.10.0
     # via
     #   python-discovery
     #   requests-cache
     #   virtualenv
-pyelftools==0.32
-    # via abi3audit
+pyelftools==0.33
+    # via
+    #   abi3audit
+    #   auditwheel
 pygments==2.20.0
     # via rich
 pyproject-hooks==1.2.0
     # via build
-python-discovery==1.3.1
+python-discovery==1.4.0
     # via virtualenv
-requests==2.34.1
+requests==2.34.2
     # via
     #   abi3audit
     #   requests-cache
@@ -82,5 +91,5 @@ urllib3==2.7.0
     # via
     #   requests
     #   requests-cache
-virtualenv==21.3.3
+virtualenv==21.4.2
     # via -r cibuildwheel/resources/constraints.in

cibuildwheel/resources/constraints-python39.txt

@@ -10,19 +10,21 @@ attrs==26.1.0
     # via
     #   cattrs
     #   requests-cache
+auditwheel==6.4.2
+    # via -r cibuildwheel/resources/constraints.in
 build==1.4.4
     # via -r cibuildwheel/resources/constraints.in
 cattrs==25.3.0
     # via requests-cache
-certifi==2026.4.22
+certifi==2026.5.20
     # via requests
 charset-normalizer==3.4.7
     # via requests
 delocate==0.13.0
     # via -r cibuildwheel/resources/constraints.in
-delvewheel==1.12.1
+delvewheel==1.13.0
     # via -r cibuildwheel/resources/constraints.in
-distlib==0.4.0
+distlib==0.4.1
     # via virtualenv
 exceptiongroup==1.3.1
     # via cattrs
@@ -30,12 +32,14 @@ filelock==3.19.1
     # via
     #   python-discovery
     #   virtualenv
-idna==3.15
+idna==3.18
     # via
     #   requests
     #   url-normalize
 importlib-metadata==8.7.1
-    # via build
+    # via
+    #   build
+    #   pkgconf
 kaitaistruct==0.11
     # via abi3audit
 macholib==1.16.4
@@ -47,26 +51,33 @@ mdurl==0.1.2
 packaging==25.0
     # via
     #   abi3audit
+    #   auditwheel
     #   build
     #   delocate
+patchelf==0.17.2.4
+    # via -r cibuildwheel/resources/constraints.in
 pefile==2024.8.26
     # via
     #   abi3audit
     #   delvewheel
 pip==26.0.1
     # via -r cibuildwheel/resources/constraints.in
+pkgconf==2.4.3.post2
+    # via -r cibuildwheel/resources/constraints.in
 platformdirs==4.4.0
     # via
     #   python-discovery
     #   requests-cache
     #   virtualenv
 pyelftools==0.32
-    # via abi3audit
+    # via
+    #   abi3audit
+    #   auditwheel
 pygments==2.20.0
     # via rich
 pyproject-hooks==1.2.0
     # via build
-python-discovery==1.3.1
+python-discovery==1.4.0
     # via virtualenv
 requests==2.32.5
     # via
@@ -90,7 +101,7 @@ urllib3==2.6.3
     # via
     #   requests
     #   requests-cache
-virtualenv==21.3.3
+virtualenv==21.4.2
     # via -r cibuildwheel/resources/constraints.in
 zipp==3.23.1
     # via importlib-metadata

cibuildwheel/resources/constraints.in

@@ -4,3 +4,8 @@ delocate
 delvewheel
 virtualenv
 abi3audit
+
+# Android
+auditwheel
+patchelf
+pkgconf

cibuildwheel/resources/constraints.txt

@@ -10,25 +10,27 @@ attrs==26.1.0
     # via
     #   cattrs
     #   requests-cache
+auditwheel==6.7.0
+    # via -r cibuildwheel/resources/constraints.in
 build==1.5.0
     # via -r cibuildwheel/resources/constraints.in
 cattrs==26.1.0
     # via requests-cache
-certifi==2026.4.22
+certifi==2026.5.20
     # via requests
 charset-normalizer==3.4.7
     # via requests
 delocate==0.13.0
     # via -r cibuildwheel/resources/constraints.in
-delvewheel==1.12.1
+delvewheel==1.13.0
     # via -r cibuildwheel/resources/constraints.in
-distlib==0.4.0
+distlib==0.4.1
     # via virtualenv
-filelock==3.29.0
+filelock==3.29.1
     # via
     #   python-discovery
     #   virtualenv
-idna==3.15
+idna==3.18
     # via
     #   requests
     #   url-normalize
@@ -43,28 +45,35 @@ mdurl==0.1.2
 packaging==26.2
     # via
     #   abi3audit
+    #   auditwheel
     #   build
     #   delocate
+patchelf==0.17.2.4
+    # via -r cibuildwheel/resources/constraints.in
 pefile==2024.8.26
     # via
     #   abi3audit
     #   delvewheel
-pip==26.1.1
+pip==26.1.2
     # via -r cibuildwheel/resources/constraints.in
-platformdirs==4.9.6
+pkgconf==2.5.1.post2
+    # via -r cibuildwheel/resources/constraints.in
+platformdirs==4.10.0
     # via
     #   python-discovery
     #   requests-cache
     #   virtualenv
-pyelftools==0.32
-    # via abi3audit
+pyelftools==0.33
+    # via
+    #   abi3audit
+    #   auditwheel
 pygments==2.20.0
     # via rich
 pyproject-hooks==1.2.0
     # via build
-python-discovery==1.3.1
+python-discovery==1.4.0
     # via virtualenv
-requests==2.34.1
+requests==2.34.2
     # via
     #   abi3audit
     #   requests-cache
@@ -82,5 +91,5 @@ urllib3==2.7.0
     # via
     #   requests
     #   requests-cache
-virtualenv==21.3.3
+virtualenv==21.4.2
     # via -r cibuildwheel/resources/constraints.in

cibuildwheel/resources/defaults.toml

@@ -1,3 +1,6 @@
+# These are the defaults used by cibuildwheel itself. They should match the values in
+# generate_schema.py, which are used by external tools for validation and IDE support.
+
 [tool.cibuildwheel]
 build = "*"
 skip = ""
@@ -52,6 +55,13 @@ musllinux-s390x-image = "musllinux_1_2"
 musllinux-armv7l-image = "musllinux_1_2"
 musllinux-riscv64-image = "musllinux_1_2"
 
+[tool.cibuildwheel.xbuild-files]
+numpy = [
+    "numpy/_core/include/numpy/_numpyconfig.h",
+    "numpy/_core/include/numpy/numpyconfig.h",
+    "numpy/_core/lib/libnpymath.a",
+    "numpy/random/lib/libnpyrandom.a",
+]
 
 [tool.cibuildwheel.linux]
 repair-wheel-command = "auditwheel repair -w {dest_dir} {wheel}"
@@ -63,6 +73,7 @@ repair-wheel-command = "delocate-wheel --require-archs {delocate_archs} -w {dest
 repair-wheel-command = "delvewheel repair -w {dest_dir} -v {wheel}"
 
 [tool.cibuildwheel.android]
+repair-wheel-command = "auditwheel repair --ldpaths {ldpaths} -w {dest_dir} {wheel}"
 
 [tool.cibuildwheel.ios]
 

cibuildwheel/resources/ios-support/_cross_venv.py

@@ -0,0 +1,103 @@
+import shutil
+import sys
+import sysconfig
+from pathlib import Path
+
+SITE_PACKAGE_PATH = Path(__file__).parent
+
+###########################################################################
+# importlib module patches
+###########################################################################
+
+
+def patch_env_create(env):
+    """
+    Patch the process of creating virtual environments to ensure that the cross
+    environment modification files are also copied as part of environment
+    creation.
+    """
+    old_pip_env_create = env._PipBackend.create
+
+    def pip_env_create(self, path, *args, **kwargs):
+        result = old_pip_env_create(self, path, *args, **kwargs)
+        # Copy any _cross_*.pth or _cross_*.py file, plus the cross-platform
+        # sysconfigdata module and sysconfig_vars JSON to the new environment.
+        data_name = sysconfig._get_sysconfigdata_name()
+        json_name = data_name.replace("_sysconfigdata", "_sysconfig_vars")
+        for filename in [
+            "_cross_venv.pth",
+            "_cross_venv.py",
+            f"_cross_{sys.implementation._multiarch.replace('-', '_')}.py",
+            f"{data_name}.py",
+            f"{json_name}.json",
+        ]:
+            src = SITE_PACKAGE_PATH / filename
+            target = Path(path) / src.relative_to(SITE_PACKAGE_PATH.parent.parent.parent)
+            if not target.exists():
+                shutil.copy(src, target)
+        return result
+
+    env._PipBackend.create = pip_env_create
+
+
+# Import hook that patches the creation of virtual environments by `build`
+#
+# The approach used here is the same as the one used by virtualenv to patch
+# distutils (but without support for the older load_module API).
+# https://docs.python.org/3/library/importlib.html#setting-up-an-importer
+_BUILD_PATCH = ("build.env",)
+
+
+class _Finder:
+    """A meta path finder that allows patching the imported build modules."""
+
+    fullname = None
+
+    # lock[0] is threading.Lock(), but initialized lazily to avoid importing
+    # threading very early at startup, because there are gevent-based
+    # applications that need to be first to import threading by themselves.
+    # See https://github.com/pypa/virtualenv/issues/1895 for details.
+    lock = []  # noqa: RUF012
+
+    def find_spec(self, fullname, path, target=None):
+        if fullname in _BUILD_PATCH and self.fullname is None:
+            # initialize lock[0] lazily
+            if len(self.lock) == 0:
+                import threading
+
+                lock = threading.Lock()
+                # there is possibility that two threads T1 and T2 are
+                # simultaneously running into find_spec, observing .lock as
+                # empty, and further going into hereby initialization. However
+                # due to the GIL, list.append() operation is atomic and this
+                # way only one of the threads will "win" to put the lock
+                # - that every thread will use - into .lock[0].
+                # https://docs.python.org/3/faq/library.html#what-kinds-of-global-value-mutation-are-thread-safe
+                self.lock.append(lock)
+
+            from functools import partial
+            from importlib.util import find_spec
+
+            with self.lock[0]:
+                self.fullname = fullname
+                try:
+                    spec = find_spec(fullname, path)
+                    if spec is not None:
+                        # https://www.python.org/dev/peps/pep-0451/#how-loading-will-work
+                        old = spec.loader.exec_module
+                        func = self.exec_module
+                        if old is not func:
+                            spec.loader.exec_module = partial(func, old)
+                        return spec
+                finally:
+                    self.fullname = None
+        return None
+
+    @staticmethod
+    def exec_module(old, module):
+        old(module)
+        if module.__name__ in _BUILD_PATCH:
+            patch_env_create(module)
+
+
+sys.meta_path.insert(0, _Finder())

cibuildwheel/resources/ios-support/arm64-iphoneos/_cross_arm64_iphoneos.py

@@ -0,0 +1,79 @@
+# A site package that turns a macOS virtual environment
+# into an arm64 iphoneos cross-platform virtual environment
+import platform
+import subprocess
+import sys
+import sysconfig
+
+###########################################################################
+# sys module patches
+###########################################################################
+sys.cross_compiling = True
+sys.platform = "ios"
+sys.implementation._multiarch = "arm64-iphoneos"
+sys.base_prefix = sysconfig._get_sysconfigdata()["prefix"]
+sys.base_exec_prefix = sysconfig._get_sysconfigdata()["prefix"]
+
+###########################################################################
+# subprocess module patches
+###########################################################################
+subprocess._can_fork_exec = True
+
+
+###########################################################################
+# platform module patches
+###########################################################################
+
+
+def cross_system():
+    return "iOS"
+
+
+def cross_uname():
+    return platform.uname_result(
+        system="iOS",
+        node="build",
+        release="13.0",
+        version="",
+        machine="arm64",
+    )
+
+
+def cross_ios_ver(system="", release="", model="", is_simulator=False):
+    if system == "":
+        system = "iOS"
+    if release == "":
+        release = "13.0"
+    if model == "":
+        model = "iphoneos"
+
+    return platform.IOSVersionInfo(system, release, model, False)
+
+
+platform.system = cross_system
+platform.uname = cross_uname
+platform.ios_ver = cross_ios_ver
+
+
+###########################################################################
+# sysconfig module patches
+###########################################################################
+
+
+def cross_get_platform():
+    return "ios-13.0-arm64-iphoneos"
+
+
+def cross_get_sysconfigdata_name():
+    return "_sysconfigdata__ios_arm64-iphoneos"
+
+
+sysconfig.get_platform = cross_get_platform
+sysconfig._get_sysconfigdata_name = cross_get_sysconfigdata_name
+
+# Ensure module-level values cached at time of import are updated.
+sysconfig._BASE_PREFIX = sys.base_prefix
+sysconfig._BASE_EXEC_PREFIX = sys.base_exec_prefix
+
+# Force sysconfig data to be loaded (and cached).
+sysconfig._init_config_vars()

cibuildwheel/resources/ios-support/arm64-iphoneos/sitecustomize.py

@@ -0,0 +1,22 @@
+# A site customization that can be used to trick pip into installing packages
+# cross-platform. If the folder containing this file is on your PYTHONPATH when
+# you invoke python, the interpreter will behave as if it were running on
+# arm64 iphoneos.
+import sys
+import os
+
+# Apply the cross-platform patch
+import _cross_arm64_iphoneos
+import _cross_venv
+
+
+# Call the next sitecustomize script if there is one
+# (https://nedbatchelder.com/blog/201001/running_code_at_python_startup.html).
+del sys.modules["sitecustomize"]
+this_dir = os.path.dirname(__file__)
+path_index = sys.path.index(this_dir)
+del sys.path[path_index]
+try:
+    import sitecustomize  # noqa: F401
+finally:
+    sys.path.insert(path_index, this_dir)

cibuildwheel/resources/ios-support/arm64-iphonesimulator/_cross_arm64_iphonesimulator.py

@@ -0,0 +1,79 @@
+# A site package that turns a macOS virtual environment
+# into an arm64 iphonesimulator cross-platform virtual environment
+import platform
+import subprocess
+import sys
+import sysconfig
+
+###########################################################################
+# sys module patches
+###########################################################################
+sys.cross_compiling = True
+sys.platform = "ios"
+sys.implementation._multiarch = "arm64-iphonesimulator"
+sys.base_prefix = sysconfig._get_sysconfigdata()["prefix"]
+sys.base_exec_prefix = sysconfig._get_sysconfigdata()["prefix"]
+
+###########################################################################
+# subprocess module patches
+###########################################################################
+subprocess._can_fork_exec = True
+
+
+###########################################################################
+# platform module patches
+###########################################################################
+
+
+def cross_system():
+    return "iOS"
+
+
+def cross_uname():
+    return platform.uname_result(
+        system="iOS",
+        node="build",
+        release="13.0",
+        version="",
+        machine="arm64",
+    )
+
+
+def cross_ios_ver(system="", release="", model="", is_simulator=False):
+    if system == "":
+        system = "iOS"
+    if release == "":
+        release = "13.0"
+    if model == "":
+        model = "iphonesimulator"
+
+    return platform.IOSVersionInfo(system, release, model, True)
+
+
+platform.system = cross_system
+platform.uname = cross_uname
+platform.ios_ver = cross_ios_ver
+
+
+###########################################################################
+# sysconfig module patches
+###########################################################################
+
+
+def cross_get_platform():
+    return "ios-13.0-arm64-iphonesimulator"
+
+
+def cross_get_sysconfigdata_name():
+    return "_sysconfigdata__ios_arm64-iphonesimulator"
+
+
+sysconfig.get_platform = cross_get_platform
+sysconfig._get_sysconfigdata_name = cross_get_sysconfigdata_name
+
+# Ensure module-level values cached at time of import are updated.
+sysconfig._BASE_PREFIX = sys.base_prefix
+sysconfig._BASE_EXEC_PREFIX = sys.base_exec_prefix
+
+# Force sysconfig data to be loaded (and cached).
+sysconfig._init_config_vars()

cibuildwheel/resources/ios-support/arm64-iphonesimulator/sitecustomize.py

@@ -0,0 +1,22 @@
+# A site customization that can be used to trick pip into installing packages
+# cross-platform. If the folder containing this file is on your PYTHONPATH when
+# you invoke python, the interpreter will behave as if it were running on
+# arm64 iphonesimulator.
+import sys
+import os
+
+# Apply the cross-platform patch
+import _cross_arm64_iphonesimulator
+import _cross_venv
+
+
+# Call the next sitecustomize script if there is one
+# (https://nedbatchelder.com/blog/201001/running_code_at_python_startup.html).
+del sys.modules["sitecustomize"]
+this_dir = os.path.dirname(__file__)
+path_index = sys.path.index(this_dir)
+del sys.path[path_index]
+try:
+    import sitecustomize  # noqa: F401
+finally:
+    sys.path.insert(path_index, this_dir)

cibuildwheel/resources/ios-support/make_cross_venv.py

@@ -0,0 +1,175 @@
+from __future__ import annotations
+
+import json
+import pprint
+import shutil
+import sys
+from importlib import util as importlib_util
+from pathlib import Path
+from typing import Any
+
+
+def localized_vars(orig_vars: dict[str, Any], slice_path: Path) -> dict[str, Any]:
+    """Update (where possible) any references to build-time variables with the
+    best guess of the installed location.
+    """
+    # The host's sysconfigdata will include references to build-time variables.
+    # Update these to refer to the current known install location.
+    orig_prefix = orig_vars["prefix"]
+    localized_vars = {}
+    for key, value in orig_vars.items():
+        final = value
+        if isinstance(value, str):
+            # Replace any reference to the build installation prefix
+            final = final.replace(orig_prefix, str(slice_path))
+            # Replace any reference to the build-time Framework location
+            final = final.replace("-F .", f"-F {slice_path}")
+        localized_vars[key] = final
+
+    return localized_vars
+
+
+def localize_sysconfigdata(sysconfig_path: Path, venv_site_packages: Path) -> None:
+    """Localize a sysconfigdata python module.
+
+    :param sysconfig_path: The platform config that contains the
+        sysconfigdata module to localize.
+    :param venv_site_packages: The site packages folder where the localized
+        sysconfigdata module should be output.
+    """
+    # Find the "_sysconfigdata_*.py" file in the platform config
+    sysconfigdata_path = next(sysconfig_path.glob("_sysconfigdata_*.py"))
+
+    # Import the sysconfigdata module
+    spec = importlib_util.spec_from_file_location(sysconfigdata_path.stem, sysconfigdata_path)
+    if spec is None:
+        msg = f"Unable to load spec for {sysconfigdata_path}"
+        raise ValueError(msg)
+    if spec.loader is None:
+        msg = f"Spec for {sysconfigdata_path} does not define a loader"
+        raise ValueError(msg)
+    sysconfigdata = importlib_util.module_from_spec(spec)
+    spec.loader.exec_module(sysconfigdata)
+
+    # Write the updated sysconfigdata module into the cross-platform site.
+    slice_path = sysconfigdata_path.parent.parent.parent
+    with (venv_site_packages / sysconfigdata_path.name).open("w") as f:
+        f.write(f"# Generated from {sysconfigdata_path}\n")
+        f.write("build_time_vars = ")
+        pprint.pprint(
+            localized_vars(sysconfigdata.build_time_vars, slice_path), stream=f, compact=True
+        )
+
+
+def localize_sysconfig_vars(sysconfig_path: Path, venv_site_packages: Path) -> None:
+    """Localize a sysconfig_vars.json file.
+
+    :param sysconfig_path: The platform config that contains the
+        sysconfigdata module to localize.
+    :param venv_site_packages: The site-packages folder where the localized
+        sysconfig_vars.json file should be output.
+    """
+    # Find the "_sysconfig_vars_*.json" file in the platform config
+    sysconfig_vars_path = next(sysconfig_path.glob("_sysconfig_vars_*.json"))
+
+    with sysconfig_vars_path.open("rb") as f:
+        build_time_vars = json.load(f)
+
+    slice_path = sysconfig_vars_path.parent.parent.parent
+    with (venv_site_packages / sysconfig_vars_path.name).open("w") as f:
+        json.dump(localized_vars(build_time_vars, slice_path), f, indent=2)
+
+
+def make_cross_venv(
+    venv_path: Path,
+    sysconfig_path: Path,
+    platform_config_path: Path,
+) -> None:
+    """Convert a virtual environment into a cross-platform environment.
+
+    :param venv_path: The path to the root of the venv.
+    :param sysconfig_path: The path containing sysconfigdata files for the
+        target platform.
+    :param platform_config_path: The path containing the cross-venv support
+        scripts (_cross_venv.py and the multiarch-specific _cross_*.py).
+    """
+    if not venv_path.exists():
+        msg = f"Virtual environment {venv_path} does not exist."
+        raise ValueError(msg)
+    if not (venv_path / "bin/python3").exists():
+        msg = f"{venv_path} does not appear to be a virtual environment."
+        raise ValueError(msg)
+
+    LIB_PATH = f"lib/python{sys.version_info[0]}.{sys.version_info[1]}"
+
+    # Derive the multiarch tag from the sysconfigdata filename if available;
+    # otherwise fall back to the directory name (BeeWare convention).
+    sysconfigdata_files = list(sysconfig_path.glob("_sysconfigdata_*.py"))
+    if sysconfigdata_files:
+        multiarch_tag = sysconfigdata_files[0].stem.split("_ios_")[1]
+        cross_multiarch = f"_cross_{multiarch_tag.replace('-', '_')}"
+    else:
+        multiarch_tag = sysconfig_path.name
+        cross_multiarch = f"_cross_{multiarch_tag.replace('-', '_')}"
+
+    print(
+        f"Converting {venv_path} into a {multiarch_tag} environment... ",
+        end="",
+    )
+
+    # Update path references in the sysconfigdata to reflect local conditions.
+    venv_site_packages = venv_path / LIB_PATH / "site-packages"
+    localize_sysconfigdata(sysconfig_path, venv_site_packages)
+    localize_sysconfig_vars(sysconfig_path, venv_site_packages)
+    # The multiarch-specific script may be directly in platform_config_path (BeeWare
+    # convention, where all files are co-located) or in a named subdirectory
+    # (cibuildwheel resource layout, where each multiarch has its own subdir).
+    multiarch_script = platform_config_path / f"{cross_multiarch}.py"
+    if not multiarch_script.exists():
+        multiarch_script = platform_config_path / multiarch_tag / f"{cross_multiarch}.py"
+    shutil.copy(
+        multiarch_script,
+        venv_site_packages / f"{cross_multiarch}.py",
+    )
+    shutil.copy(
+        platform_config_path / "_cross_venv.py",
+        venv_site_packages / "_cross_venv.py",
+    )
+    # Write the .pth file that will enable the cross-env modifications
+    (venv_site_packages / "_cross_venv.pth").write_text(
+        f"import {cross_multiarch}; import _cross_venv\n"
+    )
+
+    print("done.")
+
+
+if __name__ == "__main__":
+    try:
+        sysconfig_path = Path(sys.argv[2]).resolve()
+    except IndexError:
+        sysconfig_path = Path(__file__).parent
+
+    try:
+        platform_config_path = Path(sys.argv[3]).resolve()
+    except IndexError:
+        platform_config_path = sysconfig_path
+
+    try:
+        venv_path = Path(sys.argv[1]).resolve()
+        make_cross_venv(venv_path, sysconfig_path, platform_config_path)
+    except IndexError:
+        print("""
+Convert a virtual environment into a cross-platform environment.
+
+Usage:
+    make_cross_venv <venv> (<sysconfig path>) (<platform config path>)
+
+The sysconfig path is the path that contains the `_sysconfigdata-*.py` file
+for the platform being targeted. If an explicit sysconfig path isn't
+provided, it is assumed the directory containing the make_cross_venv script
+also contains the sysconfig data for the interpreter.
+
+The platform config path is the path that contains the cross-venv support
+scripts. If an explicit platform config path isn't provided, it is assumed
+that the sysconfig path also contains the platform configuration files.
+""")

cibuildwheel/resources/ios-support/x86_64-iphonesimulator/_cross_x86_64_iphonesimulator.py

@@ -0,0 +1,79 @@
+# A site package that turns a macOS virtual environment
+# into an x86_64 iphonesimulator cross-platform virtual environment
+import platform
+import subprocess
+import sys
+import sysconfig
+
+###########################################################################
+# sys module patches
+###########################################################################
+sys.cross_compiling = True
+sys.platform = "ios"
+sys.implementation._multiarch = "x86_64-iphonesimulator"
+sys.base_prefix = sysconfig._get_sysconfigdata()["prefix"]
+sys.base_exec_prefix = sysconfig._get_sysconfigdata()["prefix"]
+
+###########################################################################
+# subprocess module patches
+###########################################################################
+subprocess._can_fork_exec = True
+
+
+###########################################################################
+# platform module patches
+###########################################################################
+
+
+def cross_system():
+    return "iOS"
+
+
+def cross_uname():
+    return platform.uname_result(
+        system="iOS",
+        node="build",
+        release="13.0",
+        version="",
+        machine="x86_64",
+    )
+
+
+def cross_ios_ver(system="", release="", model="", is_simulator=False):
+    if system == "":
+        system = "iOS"
+    if release == "":
+        release = "13.0"
+    if model == "":
+        model = "iphonesimulator"
+
+    return platform.IOSVersionInfo(system, release, model, True)
+
+
+platform.system = cross_system
+platform.uname = cross_uname
+platform.ios_ver = cross_ios_ver
+
+
+###########################################################################
+# sysconfig module patches
+###########################################################################
+
+
+def cross_get_platform():
+    return "ios-13.0-x86_64-iphonesimulator"
+
+
+def cross_get_sysconfigdata_name():
+    return "_sysconfigdata__ios_x86_64-iphonesimulator"
+
+
+sysconfig.get_platform = cross_get_platform
+sysconfig._get_sysconfigdata_name = cross_get_sysconfigdata_name
+
+# Ensure module-level values cached at time of import are updated.
+sysconfig._BASE_PREFIX = sys.base_prefix
+sysconfig._BASE_EXEC_PREFIX = sys.base_exec_prefix
+
+# Force sysconfig data to be loaded (and cached).
+sysconfig._init_config_vars()

cibuildwheel/resources/ios-support/x86_64-iphonesimulator/sitecustomize.py

@@ -0,0 +1,22 @@
+# A site customization that can be used to trick pip into installing packages
+# cross-platform. If the folder containing this file is on your PYTHONPATH when
+# you invoke python, the interpreter will behave as if it were running on
+# x86_64 iphonesimulator.
+import sys
+import os
+
+# Apply the cross-platform patch
+import _cross_x86_64_iphonesimulator
+import _cross_venv
+
+
+# Call the next sitecustomize script if there is one
+# (https://nedbatchelder.com/blog/201001/running_code_at_python_startup.html).
+del sys.modules["sitecustomize"]
+this_dir = os.path.dirname(__file__)
+path_index = sys.path.index(this_dir)
+del sys.path[path_index]
+try:
+    import sitecustomize  # noqa: F401
+finally:
+    sys.path.insert(path_index, this_dir)

cibuildwheel/resources/nodejs.toml

@@ -1,4 +1,4 @@
 url = "https://nodejs.org/dist/"
-v24 = "v24.15.0"
-v22 = "v22.22.2"
+v24 = "v24.16.0"
+v22 = "v22.22.3"
 v20 = "v20.20.2"

cibuildwheel/resources/pinned_docker_images.cfg

@@ -1,54 +1,54 @@
 [x86_64]
-manylinux2014 = quay.io/pypa/manylinux2014_x86_64:2026.05.07-2
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_x86_64:2026.05.07-2
-manylinux_2_34 = quay.io/pypa/manylinux_2_34_x86_64:2026.05.07-2
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_x86_64:2026.05.07-2
+manylinux2014 = quay.io/pypa/manylinux2014_x86_64:2026.06.04-1
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_x86_64:2026.06.04-1
+manylinux_2_34 = quay.io/pypa/manylinux_2_34_x86_64:2026.06.04-1
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_x86_64:2026.06.04-1
 
 [i686]
-manylinux2014 = quay.io/pypa/manylinux2014_i686:2026.05.07-2
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_i686:2026.05.07-2
-manylinux_2_34 = quay.io/pypa/manylinux_2_34_i686:2026.05.07-2
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_i686:2026.05.07-2
+manylinux2014 = quay.io/pypa/manylinux2014_i686:2026.06.04-1
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_i686:2026.06.04-1
+manylinux_2_34 = quay.io/pypa/manylinux_2_34_i686:2026.06.04-1
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_i686:2026.06.04-1
 
 [aarch64]
-manylinux2014 = quay.io/pypa/manylinux2014_aarch64:2026.05.07-2
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_aarch64:2026.05.07-2
-manylinux_2_34 = quay.io/pypa/manylinux_2_34_aarch64:2026.05.07-2
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_aarch64:2026.05.07-2
+manylinux2014 = quay.io/pypa/manylinux2014_aarch64:2026.06.04-1
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_aarch64:2026.06.04-1
+manylinux_2_34 = quay.io/pypa/manylinux_2_34_aarch64:2026.06.04-1
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_aarch64:2026.06.04-1
 
 [ppc64le]
-manylinux2014 = quay.io/pypa/manylinux2014_ppc64le:2026.05.07-2
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_ppc64le:2026.05.07-2
-manylinux_2_34 = quay.io/pypa/manylinux_2_34_ppc64le:2026.05.07-2
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_ppc64le:2026.05.07-2
+manylinux2014 = quay.io/pypa/manylinux2014_ppc64le:2026.06.04-1
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_ppc64le:2026.06.04-1
+manylinux_2_34 = quay.io/pypa/manylinux_2_34_ppc64le:2026.06.04-1
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_ppc64le:2026.06.04-1
 
 [s390x]
-manylinux2014 = quay.io/pypa/manylinux2014_s390x:2026.05.07-2
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_s390x:2026.05.07-2
-manylinux_2_34 = quay.io/pypa/manylinux_2_34_s390x:2026.05.07-2
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_s390x:2026.05.07-2
+manylinux2014 = quay.io/pypa/manylinux2014_s390x:2026.06.04-1
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_s390x:2026.06.04-1
+manylinux_2_34 = quay.io/pypa/manylinux_2_34_s390x:2026.06.04-1
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_s390x:2026.06.04-1
 
 [pypy_x86_64]
-manylinux2014 = quay.io/pypa/manylinux2014_x86_64:2026.05.07-2
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_x86_64:2026.05.07-2
-manylinux_2_34 = quay.io/pypa/manylinux_2_34_x86_64:2026.05.07-2
+manylinux2014 = quay.io/pypa/manylinux2014_x86_64:2026.06.04-1
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_x86_64:2026.06.04-1
+manylinux_2_34 = quay.io/pypa/manylinux_2_34_x86_64:2026.06.04-1
 
 [pypy_i686]
-manylinux2014 = quay.io/pypa/manylinux2014_i686:2026.05.07-2
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_i686:2026.05.07-2
-manylinux_2_34 = quay.io/pypa/manylinux_2_34_i686:2026.05.07-2
+manylinux2014 = quay.io/pypa/manylinux2014_i686:2026.06.04-1
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_i686:2026.06.04-1
+manylinux_2_34 = quay.io/pypa/manylinux_2_34_i686:2026.06.04-1
 
 [pypy_aarch64]
-manylinux2014 = quay.io/pypa/manylinux2014_aarch64:2026.05.07-2
-manylinux_2_28 = quay.io/pypa/manylinux_2_28_aarch64:2026.05.07-2
-manylinux_2_34 = quay.io/pypa/manylinux_2_34_aarch64:2026.05.07-2
+manylinux2014 = quay.io/pypa/manylinux2014_aarch64:2026.06.04-1
+manylinux_2_28 = quay.io/pypa/manylinux_2_28_aarch64:2026.06.04-1
+manylinux_2_34 = quay.io/pypa/manylinux_2_34_aarch64:2026.06.04-1
 
 [armv7l]
-manylinux_2_31 = quay.io/pypa/manylinux_2_31_armv7l:2026.05.07-2
-manylinux_2_35 = quay.io/pypa/manylinux_2_35_armv7l:2026.05.07-2
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_armv7l:2026.05.07-2
+manylinux_2_31 = quay.io/pypa/manylinux_2_31_armv7l:2026.06.04-1
+manylinux_2_35 = quay.io/pypa/manylinux_2_35_armv7l:2026.06.04-1
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_armv7l:2026.06.04-1
 
 [riscv64]
-manylinux_2_39 = quay.io/pypa/manylinux_2_39_riscv64:2026.05.07-2
-musllinux_1_2 = quay.io/pypa/musllinux_1_2_riscv64:2026.05.07-2
+manylinux_2_39 = quay.io/pypa/manylinux_2_39_riscv64:2026.06.04-1
+musllinux_1_2 = quay.io/pypa/musllinux_1_2_riscv64:2026.06.04-1
 

cibuildwheel/resources/virtualenv.toml

@@ -1 +1 @@
-default = { version = "21.3.1", url = "https://github.com/pypa/get-virtualenv/releases/download/21.3.1/virtualenv.pyz" }
+default = { version = "21.4.2", url = "https://github.com/pypa/get-virtualenv/releases/download/21.4.2/virtualenv.pyz", sha256 = "b54c48b9c81468403626762747c5ee5939616f18f46c3c4bbebdbe0aa3a8ba1d" }

cibuildwheel/schema.py

@@ -1,8 +1,13 @@
+from __future__ import annotations
+
 import json
-from typing import Any
 
 from cibuildwheel.util import resources
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from typing import Any
+
 
 def get_schema(tool_name: str = "cibuildwheel") -> dict[str, Any]:
     "Get the stored complete schema for cibuildwheel settings."

cibuildwheel/selector.py

@@ -1,13 +1,19 @@
+from __future__ import annotations
+
 import dataclasses
 import itertools
 from enum import StrEnum
 from fnmatch import fnmatch
-from typing import Self
 
 import bracex
-from packaging.specifiers import SpecifierSet
 from packaging.version import Version
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from typing import Self
+
+    from packaging.specifiers import SpecifierSet
+
 
 def selector_matches(patterns: str, string: str) -> bool:
     """

cibuildwheel/util/cmd.py

@@ -1,14 +1,20 @@
+from __future__ import annotations
+
 import os
 import shlex
 import shutil
 import subprocess
 import sys
 import typing
-from collections.abc import Iterator, Mapping
-from typing import Final, Literal
 
 from cibuildwheel.errors import FatalError
-from cibuildwheel.typing import PathOrStr
+
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Iterator, Mapping
+    from typing import Final, Literal
+
+    from cibuildwheel.typing import PathOrStr
 
 _IS_WIN: Final[bool] = sys.platform.startswith("win")
 

cibuildwheel/util/file.py

@@ -1,10 +1,13 @@
+from __future__ import annotations
+
+import hashlib
 import os
 import shutil
 import ssl
 import tarfile
 import time
 import urllib.request
-from collections.abc import Callable
+from contextlib import contextmanager
 from pathlib import Path, PurePath
 from typing import Final
 from zipfile import ZipFile
@@ -14,12 +17,32 @@ from platformdirs import user_cache_path
 
 from cibuildwheel.errors import FatalError
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Callable, Generator
+
 DEFAULT_CIBW_CACHE_PATH: Final[Path] = user_cache_path(appname="cibuildwheel", appauthor="pypa")
 CIBW_CACHE_PATH: Final[Path] = Path(
     os.environ.get("CIBW_CACHE_PATH", DEFAULT_CIBW_CACHE_PATH)
 ).resolve()
 
 
+@contextmanager
+def remove_on_error(path: Path) -> Generator[None, None, None]:
+    try:
+        yield
+    except BaseException as original_exception:
+        try:
+            if path.is_dir() and not path.is_symlink():
+                shutil.rmtree(path)
+            elif path.exists() or path.is_symlink():
+                path.unlink()
+        except BaseException as cleanup_exception:
+            msg = f"Failed to remove {path}. Please remove it manually."
+            raise BaseExceptionGroup(msg, [original_exception, cleanup_exception]) from None
+        raise
+
+
 def ensure_cache_sentinel(cache_path: Path) -> None:
     """Create a sentinel file to mark a cibuildwheel cache directory.
 
@@ -40,7 +63,7 @@ def ensure_cache_sentinel(cache_path: Path) -> None:
             )
 
 
-def download(url: str, dest: Path) -> None:
+def download(url: str, dest: Path, *, sha256: str | None = None) -> None:
     print(f"+ Download {url} to {dest}")
     dest_dir = dest.parent
     dest_dir.mkdir(parents=True, exist_ok=True)
@@ -54,13 +77,20 @@ def download(url: str, dest: Path) -> None:
         try:
             with urllib.request.urlopen(url, context=context) as response:
                 dest.write_bytes(response.read())
-                return
+                break
 
         except OSError:
             if i == repeat_num - 1:
                 raise
             time.sleep(3)
 
+    if sha256:
+        computed = hashlib.sha256(dest.read_bytes()).hexdigest()
+        if computed != sha256:
+            dest.unlink(missing_ok=True)
+            msg = f"SHA256 mismatch for {url}: expected {sha256!r}, got {computed!r}"
+            raise FatalError(msg)
+
 
 def extract_zip(zip_src: Path, dest: Path) -> None:
     """Extracts a zip and correctly sets permissions on extracted files.

cibuildwheel/util/helpers.py

@@ -1,13 +1,18 @@
+from __future__ import annotations
+
 import dataclasses
 import itertools
-import os
 import re
 import shlex
 import textwrap
 from collections import defaultdict
-from collections.abc import Sequence
 
-from cibuildwheel.typing import PathOrStr
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    import os
+    from collections.abc import Sequence
+
+    from cibuildwheel.typing import PathOrStr
 
 
 def format_safe(template: str, **kwargs: str | os.PathLike[str]) -> str:
@@ -104,7 +109,7 @@ def parse_key_value_string(
     if kw_arg_names is None:
         kw_arg_names = []
 
-    all_field_names = [*positional_arg_names, *kw_arg_names]
+    all_field_names = None if ("*" in kw_arg_names) else [*positional_arg_names, *kw_arg_names]
 
     shlexer = shlex.shlex(key_value_string, posix=True, punctuation_chars=";")
     shlexer.commenters = ""
@@ -121,7 +126,7 @@ def parse_key_value_string(
         # check to see if the option name is specified
         field_name, sep, first_value = field[0].partition(":")
         if sep:
-            if field_name not in all_field_names:
+            if (all_field_names is not None) and (field_name not in all_field_names):
                 msg = f"Failed to parse {key_value_string!r}. Unknown field name {field_name!r}"
                 raise ValueError(msg)
 

cibuildwheel/util/packaging.py

@@ -1,8 +1,9 @@
+from __future__ import annotations
+
 import shlex
-from collections.abc import Mapping, Sequence
 from dataclasses import dataclass, field
 from pathlib import Path, PurePath
-from typing import Literal, Self, TypeVar
+from typing import TypeVar
 
 from packaging.utils import parse_wheel_filename
 
@@ -10,6 +11,11 @@ from cibuildwheel.util import resources
 from cibuildwheel.util.cmd import call
 from cibuildwheel.util.helpers import parse_key_value_string, unwrap
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Mapping, Sequence
+    from typing import Literal, Self
+
 
 @dataclass(kw_only=True)
 class DependencyConstraints:

cibuildwheel/util/python_build_standalone.py

@@ -1,19 +1,27 @@
+from __future__ import annotations
+
 import fnmatch
 import functools
+import hashlib
 import json
 import platform
+import subprocess
 import typing
-from pathlib import Path
 
 from filelock import FileLock
 
-from cibuildwheel.util.file import download, extract_tar
+from cibuildwheel.util.file import download, extract_tar, remove_on_error
 from cibuildwheel.util.resources import PYTHON_BUILD_STANDALONE_RELEASES
 
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from pathlib import Path
+
 
 class PythonBuildStandaloneAsset(typing.TypedDict):
     name: str
     url: str
+    sha256: str
 
 
 class PythonBuildStandaloneRelease(typing.TypedDict):
@@ -35,6 +43,26 @@ class PythonBuildStandaloneError(Exception):
     """Errors related to python-build-standalone."""
 
 
+def _is_musl_libc() -> bool:
+    """
+    Detect whether the host uses musl libc (e.g. Alpine Linux).
+
+    ``platform.libc_ver()`` only ever reports glibc, so we shell out to ``ldd``,
+    which prints "musl libc" on musl-based systems (and "GNU libc"/"GLIBC" on
+    glibc systems). If ``ldd`` is unavailable, we fall back to assuming glibc.
+    """
+    try:
+        ldd = subprocess.run(
+            ["ldd", "--version"],
+            capture_output=True,
+            text=True,
+            check=False,
+        )
+    except OSError:
+        return False
+    return "musl" in (ldd.stdout + ldd.stderr).lower()
+
+
 def _get_platform_identifiers() -> tuple[str, str, str | None]:
     """
     Detects the current platform and returns architecture, platform, and libc
@@ -60,7 +88,7 @@ def _get_platform_identifiers() -> tuple[str, str, str | None]:
     # Map OS + Libc
     if system == "Linux":
         platform_identifier = "unknown-linux"
-        libc_identifier = "musl" if "musl" in (platform.libc_ver() or ("", "")) else "gnu"
+        libc_identifier = "musl" if _is_musl_libc() else "gnu"
     elif system == "Darwin":
         platform_identifier = "apple-darwin"
     elif system == "Windows":
@@ -81,8 +109,8 @@ def _get_pbs_asset(
     arch_identifier: str,
     platform_identifier: str,
     libc_identifier: str | None,
-) -> tuple[str, str, str]:
-    """Finds the asset, returning (tag, filename, url)."""
+) -> tuple[str, str, str, str]:
+    """Finds the asset, returning (tag, url, filename, sha256)."""
     release_data = get_python_build_standalone_release_data()
 
     expected_suffix = f"{arch_identifier}-{platform_identifier}"
@@ -100,22 +128,37 @@ def _get_pbs_asset(
                 continue
 
             asset_url = asset["url"]
-            return release["tag"], asset_url, asset_name
+            asset_sha256 = asset.get("sha256", "")
+            return release["tag"], asset_url, asset_name, asset_sha256
 
     # If loop completes without finding a match
     msg = f"Could not find python-build-standalone release asset matching {asset_pattern!r}."
     raise PythonBuildStandaloneError(msg)
 
 
-def _download_or_get_from_cache(asset_url: str, asset_filename: str, cache_dir: Path) -> Path:
+def _download_or_get_from_cache(
+    asset_url: str, asset_filename: str, cache_dir: Path, sha256: str = ""
+) -> Path:
     with FileLock(cache_dir / (asset_filename + ".lock")):
         asset_cache_path = cache_dir / asset_filename
         if asset_cache_path.is_file():
-            print(f"Using cached python_build_standalone: {asset_cache_path}")
-            return asset_cache_path
+            if sha256:
+                computed = hashlib.sha256(asset_cache_path.read_bytes()).hexdigest()
+                if computed != sha256:
+                    print(
+                        f"Cached python_build_standalone SHA256 mismatch for {asset_cache_path}; redownloading."
+                    )
+                    asset_cache_path.unlink(missing_ok=True)
+                else:
+                    print(f"Using cached python_build_standalone: {asset_cache_path}")
+                    return asset_cache_path
+            else:
+                print(f"Using cached python_build_standalone: {asset_cache_path}")
+                return asset_cache_path
 
         print(f"Downloading python_build_standalone: {asset_url} to {asset_cache_path}")
-        download(asset_url, asset_cache_path)
+        with remove_on_error(asset_cache_path):
+            download(asset_url, asset_cache_path, sha256=sha256 or None)
         return asset_cache_path
 
 
@@ -161,7 +204,7 @@ def create_python_build_standalone_environment(
 
     arch_id, platform_id, libc_id = _get_platform_identifiers()
 
-    pbs_tag, asset_url, asset_filename = _get_pbs_asset(
+    pbs_tag, asset_url, asset_filename, asset_sha256 = _get_pbs_asset(
         python_version=python_version,
         arch_identifier=arch_id,
         platform_identifier=platform_id,
@@ -171,11 +214,13 @@ def create_python_build_standalone_environment(
     print(f"Using python-build-standalone release: {pbs_tag}")
 
     archive_path = _download_or_get_from_cache(
-        asset_url=asset_url, asset_filename=asset_filename, cache_dir=cache_dir
+        asset_url=asset_url, asset_filename=asset_filename, cache_dir=cache_dir, sha256=asset_sha256
     )
 
     python_base_dir = temp_dir / "pbs"
-    assert not python_base_dir.exists()
+    if python_base_dir.exists():
+        msg = f"python-build-standalone directory already exists: {python_base_dir}"
+        raise PythonBuildStandaloneError(msg)
     extract_tar(archive_path, python_base_dir)
 
     return _find_python_executable(python_base_dir)

cibuildwheel/util/resources.py

@@ -1,9 +1,14 @@
+from __future__ import annotations
+
 import functools
 import tomllib
 from pathlib import Path
-from typing import Final
 
-from cibuildwheel.typing import PlatformName
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from typing import Final
+
+    from cibuildwheel.typing import PlatformName
 
 PATH: Final[Path] = Path(__file__).parent.parent / "resources"
 INSTALL_CERTIFI_SCRIPT: Final[Path] = PATH / "install_certifi.py"
@@ -18,6 +23,7 @@ VIRTUALENV: Final[Path] = PATH / "virtualenv.toml"
 CIBUILDWHEEL_SCHEMA: Final[Path] = PATH / "cibuildwheel.schema.json"
 PYTHON_BUILD_STANDALONE_RELEASES: Final[Path] = PATH / "python-build-standalone-releases.json"
 TEST_FAIL_CWD_FILE: Final[Path] = PATH / "testing_temp_dir_file.py"
+IOS_SUPPORT_FILES: Final[Path] = PATH / "ios-support"
 
 
 # this value is cached because it's used a lot in unit tests
@@ -25,7 +31,14 @@ TEST_FAIL_CWD_FILE: Final[Path] = PATH / "testing_temp_dir_file.py"
 def read_all_configs() -> dict[str, list[dict[str, str]]]:
     with BUILD_PLATFORMS.open("rb") as f:
         loaded_file = tomllib.load(f)
-    return {k: list[dict[str, str]](v["python_configurations"]) for k, v in loaded_file.items()}
+    configs = {k: list[dict[str, str]](v["python_configurations"]) for k, v in loaded_file.items()}
+    for platform, python_configs in configs.items():
+        for config in python_configs:
+            if "url" in config and not config.get("sha256"):
+                identifier = config["identifier"]
+                msg = f"{platform} Python configuration {identifier!r} is missing a sha256"
+                raise ValueError(msg)
+    return configs
 
 
 def read_python_configs(config: PlatformName) -> list[dict[str, str]]:

cibuildwheel/venv.py

@@ -1,12 +1,13 @@
+from __future__ import annotations
+
 import contextlib
 import functools
 import os
 import shutil
 import sys
 import tomllib
-from collections.abc import Sequence
 from pathlib import Path
-from typing import Final, cast
+from typing import cast
 
 from filelock import FileLock
 from packaging.markers import default_environment
@@ -15,7 +16,12 @@ from packaging.version import Version
 
 from cibuildwheel.util import resources
 from cibuildwheel.util.cmd import call
-from cibuildwheel.util.file import CIBW_CACHE_PATH, download
+from cibuildwheel.util.file import CIBW_CACHE_PATH, download, remove_on_error
+
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from collections.abc import Sequence
+    from typing import Final
 
 _IS_WIN: Final[bool] = sys.platform.startswith("win")
 
@@ -47,10 +53,12 @@ def _ensure_virtualenv(version: str) -> tuple[Path, Version]:
     configuration = loaded_file.get(key, loaded_file["default"])
     version = str(configuration["version"])
     url = str(configuration["url"])
+    sha256 = str(configuration["sha256"])
     path = CIBW_CACHE_PATH / f"virtualenv-{version}.pyz"
     with FileLock(str(path) + ".lock"):
         if not path.exists():
-            download(url, path)
+            with remove_on_error(path):
+                download(url, path, sha256=sha256)
     return (path, Version(version))
 
 
@@ -77,7 +85,7 @@ def _parse_pip_constraint_for_virtualenv(
     If it can't get an exact version, the real constraint will be handled by the
     {macos|windows}.setup_python function.
     If marker_env is provided, marker-bearing constraints are evaluated against it;
-    otherwise, marker-bearing constraints are skipped.
+    otherwise, they are evaluated against the host's default environment.
     """
     env: dict[str, str] = (
         marker_env if marker_env is not None else cast("dict[str, str]", default_environment())

docs/_internal/pyodide-maintenance.md

@@ -28,10 +28,10 @@ For example, consider a scenario when Pyodide ships a new `315.0.0a1` with cp315
 In `cibuildwheel/resources/build-platforms.toml`, add an entry under `[pyodide]`:
 
 ```toml
-{ identifier = "cp315-pyodide_wasm32", version = "3.15", default_pyodide_version = "315.0.0a1", node_version = "v24" },
+{ identifier = "cp315-pyodide_wasm32", version = "3.15", default_pyodide_version = "315.0.0a1", node_version = "v24", sha256 = "SHA256" },
 ```
 
-`version` is the CPython version string, `default_pyodide_version` is the Pyodide release to use when the user does not pin one explicitly (use the latest available alpha/beta for a prerelease entry), and `node_version` is the minimum Node.js major required by that Pyodide release — check the [pyodide-build FAQ](https://pyodide-build.readthedocs.io/en/latest/faq.html#what-node-js-version-do-i-need) for a rudimentary idea of what the correct value is.
+`version` is the CPython version string, `default_pyodide_version` is the Pyodide release to use when the user does not pin one explicitly (use the latest available alpha/beta for a prerelease entry), and `node_version` is the minimum Node.js major required by that Pyodide release — check the [pyodide-build FAQ](https://pyodide-build.readthedocs.io/en/latest/faq.html#what-node-js-version-do-i-need) for a rudimentary idea of what the correct value is. `sha256` is the checksum of the Pyodide xbuildenv tarball.
 
 ### 2. Update the prerelease guards in the selector
 

docs/changelog.md

@@ -1,9 +1,38 @@
 ---
 title: Changelog
+ref: changelog
 ---
 
 # Changelog
 
+### v4.0.0rc2
+
+_5 June 2026_
+
+- ✨ Adds CPython 3.15 support for iOS and Android (#2857, #2858)
+- ✨ Adds Android improvements for building NumPy and related packages, including auditwheel support, pkg-config and Fortran configuration, and the [`xbuild-files`](https://cibuildwheel.pypa.io/en/stable/options/#xbuild-files) option (#2695)
+- ✨ Adds `CIBUILDWHEEL_BUILD_IDENTIFIER` environment variable set to the current build identifier (e.g. `cp311-manylinux_x86_64`) during per-build steps (#2872)
+- 🔐 Adds SHA256 verification for direct downloads of Python interpreters, virtualenv, and python-build-standalone assets (#2873)
+- 🔐 Adds tarfile extraction filter for safe archive extraction (#2856)
+- 🐛 Fixes detection of musl libc when downloading python-build-standalone, which previously always selected the gnu asset on musl hosts like Alpine (#2889)
+- 🐛 Fixes [`config-settings`](https://cibuildwheel.pypa.io/en/stable/options/#config-settings) expansion when `{project}` or `{package}` contains spaces or backslashes (#2886)
+- 🐛 Prevents deadlock when `linux32` fails and forwards platform args to the sanity check (#2880, #2888)
+- 🐛 Fixes container resource leaks on start failure and during teardown (#2879, #2887)
+- 🐛 Removes potential partial cache-population in case of error (#2892)
+- 🐛 Raises a clear error when `ANDROID_API_LEVEL` is not an integer (#2891)
+- 🐛 Replaces assert with proper exception in python-build-standalone (#2859)
+- 🛠 Updates dependencies and container pins (#2893, #2882, #2874, #2868, #2862, #2884)
+- 🛠 Minor fixups across error messages, OCI container, and options (#2860)
+- 📚 Updates documentation for delvewheel as the default Windows [`repair-wheel-command`](https://cibuildwheel.pypa.io/en/stable/options/#repair-wheel-command), including the build diagram, schema defaults, and legal note (#2877, #2853, #2891)
+- 📚 Adds intersphinx support for external documentation linking (#2871)
+- 📚 Removes outdated numpy info (#2855)
+- 💼 Improves Azure test reliability with retries and caching (#2890)
+- 💼 Fixes Windows GitLab CI test running (#2870)
+- 💼 Updates CI action pins (#2867)
+- 💼 Adds agent and copilot setup files (#2861)
+- 💼 Uses `if TYPE_CHECKING:` blocks (#2866, #2864)
+- 🧪 Adds unit tests for `OCIContainer._get_platform_args` (#2878)
+
 ### v4.0.0rc1
 
 _14 May 2026_

docs/ci-services.md

@@ -1,5 +1,6 @@
 ---
 title: Configuring a CI service
+ref: ci-services
 ---
 
 ## Configuring a CI service

docs/configuration.md

@@ -1,3 +1,8 @@
+---
+title: Configuration
+ref: configuration
+---
+
 # Configuration methods
 
 cibuildwheel can either be configured using environment variables, or from
@@ -58,8 +63,8 @@ cibuildwheel to run tests, add the following YAML to your CI config file:
 You can configure cibuildwheel with a config file, such as `pyproject.toml`.
 Options have the same names as the environment variable overrides, but are
 placed in `[tool.cibuildwheel]` and are lower case, with dashes, following
-common [TOML](https://toml.io) practice. Anything placed in subsections `linux`, `windows`,
-`macos`, or `pyodide` will only affect those platforms. Lists can be used
+common [TOML](https://toml.io) practice. Anything placed in subsections
+named after a platform will only affect those platforms. Lists can be used
 instead of strings for items that are naturally a list. Multiline strings also
 work just like in the environment variables. Environment variables will take
 precedence if defined.

docs/contributing.md

@@ -1,5 +1,6 @@
 ---
 title: Contributing
+ref: contributing
 ---
 
 # Contributing
@@ -26,7 +27,7 @@ Other notes:
 
 ### cibuildwheel's relationship with build errors
 
-cibuildwheel doesn't really do anything itself - it's always deferring to other tools (pip, wheel, auditwheel, delocate, docker). Without cibuildwheel, the process is really fragmented. Different tools, across different OSs need to be stitched together in just the right way to make it work.
+cibuildwheel doesn't really do anything itself - it's always deferring to other tools (pip, wheel, auditwheel, delocate, delvewheel, docker). Without cibuildwheel, the process is really fragmented. Different tools, across different OSs need to be stitched together in just the right way to make it work.
 
 We're not responsible for errors in those tools, for fixing errors/crashes there. But cibuildwheel's job is providing users with an 'integrated' user experience across those tools. We provide an abstraction. The user says 'build me some wheels', not 'open the docker container, build a wheel with pip, fix up the symbols with auditwheel' etc.  However, errors have a habit of breaking abstractions. And this is where users get confused, because the mechanism of cibuildwheel is laid bare, and they must understand a little bit how it works to debug.
 

docs/cpp_standards.md

@@ -1,5 +1,6 @@
 ---
 title: Modern C++ standards
+ref: cpp-standards
 ---
 
 # Modern C++ standards

docs/deliver-to-pypi.md

@@ -1,5 +1,6 @@
 ---
 title: Delivering to PyPI
+ref: deliver-to-pypi
 ---
 
 # Delivering to PyPI

docs/diagram.html

@@ -179,19 +179,30 @@
           },
         },
         {
-          label: 'Repair wheel',
+          label: 'Repair using auditwheel',
           href: 'options/#repair-wheel-command',
           platforms: ['android'],
           style: 'block',
           tooltip: {
             title: 'CIBW_REPAIR_WHEEL_COMMAND',
             tag: 'Customisable step',
-            description: 'By default, bundles libc++ into the wheel if any shared library links against it, using patchelf. Can be overridden with a custom repair command.'
+            description: 'Bundle shared libraries by running auditwheel on each built wheel.'
+          },
+        },
+        {
+          label: 'Repair using delvewheel',
+          href: 'options/#repair-wheel-command',
+          platforms: ['windows'],
+          style: 'block',
+          tooltip: {
+            title: 'CIBW_REPAIR_WHEEL_COMMAND',
+            tag: 'Customisable step',
+            description: 'Bundle shared libraries by running delvewheel on each built wheel.'
           },
         },
         {
           href: 'options/#repair-wheel-command',
-          platforms: ['windows', 'ios', 'pyodide'],
+          platforms: ['ios', 'pyodide'],
           style: 'dot',
           tooltip: {
             title: 'CIBW_REPAIR_WHEEL_COMMAND',

docs/faq.md

@@ -1,5 +1,6 @@
 ---
 title: Tips and tricks
+ref: faq
 ---
 
 # Tips and tricks
@@ -51,20 +52,7 @@ myextension = Extension(
 
 ### Building with NumPy
 
-If using NumPy, there are a couple of things that can help.
-
-First, if you require the `numpy` package at build-time (some binding tools, like `pybind11` and `nanobind`, do not), then the backward compatibility for your `build-backend.build-requires` is a little complicated for Python <3.9:
-
-* NumPy <1.25: You must build with the oldest version of NumPy you want to support at runtime.
-* NumPy 1.25 and 1.26: Anything you build will be compatible with 1.19+ by default, and you can set the minimum target to, for example, 1.22 with `#define NPY_TARGET_VERSION NPY_1_22_API_VERSION`.
-* NumPy 2.x: You must build with NumPy 2 to support NumPy 2; otherwise the same as 1.25+.
-
-So the rule is:
-
-* Python <3.8: Use the oldest supported NumPy (via helper `oldest-supported-numpy` if you want)
-* Python 3.9+: Use latest supported NumPy (2+).
-
-Second, there might be platforms you want to ship for that NumPy (or some other scientific Python libraries) are not shipping yet for. This is often true for beta candidates of new Python releases, for example. To work with this, you can use the Scientific Python Nightly wheels. Here's an example, depending on what frontend you use:
+If using NumPy, there might be platforms you want to ship for that NumPy (or some other scientific Python libraries) are not shipping yet for. This is often true for beta candidates of new Python releases, for example. To work with this, you can use the Scientific Python Nightly wheels. Here's an example, depending on what frontend you use:
 
 !!! tab "pip based"
     For frontends like `build` (the default) and `pip`:
@@ -125,7 +113,7 @@ There are two suggested methods for keeping cibuildwheel up to date that instead
 If you use GitHub Actions for builds, you can use cibuildwheel as an action:
 
 ```yaml
-uses: pypa/cibuildwheel@v4.0.0rc1
+uses: pypa/cibuildwheel@v4.0.0rc2
 ```
 
 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.
@@ -150,7 +138,7 @@ The second option, and the only one that supports other CI systems, is using a `
 
 ```bash
 # requirements-cibw.txt
-cibuildwheel==4.0.0rc1
+cibuildwheel==4.0.0rc2
 ```
 
 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:
@@ -247,7 +235,7 @@ Sometimes a build will fail due to a missing dependency.
 
 **If you need a build tool** (e.g. cmake, automake, ninja), you can install it through a package manager like apt/yum, brew or choco, using the [`before-all`](options.md#before-all) option.
 
-**If your build is linking into a native library dependency**, you can build/install that in [`before-all`](options.md#before-all). However, on Linux, Mac (and Windows if you're using [delvewheel]), the library that you install will be bundled into the wheel in the [repair step]. So take care to ensure that
+**If your build is linking into a native library dependency**, you can build/install that in [`before-all`](options.md#before-all). However, on Linux, Mac, and Windows (which uses [delvewheel] by default since cibuildwheel 4.0), the library that you install will be bundled into the wheel in the [repair step]. So take care to ensure that
 
 - the bundled library doesn't accidentally increase the minimum system requirements (such as the minimum macOS version)
 - the bundled library matches the architecture of the wheel you're building when cross-compiling
@@ -315,7 +303,7 @@ Solutions to this vary, but the simplest is to use pipx:
 # most runners have pipx preinstalled, but in case you don't
 python3 -m pip install pipx
 
-pipx run cibuildwheel==4.0.0rc1 --output-dir wheelhouse
+pipx run cibuildwheel==4.0.0rc2 --output-dir wheelhouse
 pipx run twine upload wheelhouse/*.whl
 ```
 

docs/index.md

@@ -1,5 +1,6 @@
 ---
 title: Home
+ref: index
 ---
 
 # cibuildwheel

docs/options.md

@@ -1,3 +1,8 @@
+---
+title: Options
+ref: options
+---
+
 # Options
 
 <div class="options-toc"></div>
@@ -669,6 +674,9 @@ Platform-specific environment variables are also available:<br/>
 !!! note
     cibuildwheel always defines the environment variable `CIBUILDWHEEL=1`. This can be useful for [building wheels with optional extensions](faq.md#optional-extensions).
 
+!!! note
+    For each per-build step (`before_build`, the build itself, `repair_command`, `before_test`, `test_command`), cibuildwheel also sets `CIBUILDWHEEL_BUILD_IDENTIFIER` to the current build identifier (e.g. `cp311-manylinux_x86_64`). This can be used in scripts to distinguish different builds.
+
 !!! note
     To do its work, cibuildwheel sets the variables `VIRTUALENV_PIP`, `DIST_EXTRA_CONFIG`, `SETUPTOOLS_EXT_SUFFIX`, `PIP_DISABLE_PIP_VERSION_CHECK`, `PIP_ROOT_USER_ACTION`, and it extends the variables `PATH` and `PIP_CONSTRAINT`. Your assignments to these options might be replaced or extended.
 
@@ -916,15 +924,44 @@ Platform-specific environment variables are also available on platforms that use
     ```
 
 
+### `xbuild-files` {: #xbuild-files env-var toml}
+> Platform-specific files in the build environment
+
+When cross-compiling a package for Android, any dependencies in its [`build-system.requires`](https://packaging.python.org/en/latest/guides/writing-pyproject-toml/) are installed for the build platform. However, some dependencies contain platform-specific files such as headers and static libraries, which must correspond to the target platform.
+
+This option maps a [normalized](https://packaging.python.org/en/latest/specifications/name-normalization/#name-normalization) package name to a list of paths within that package. If the package is present in the build environment, then a matching version will be downloaded for the target platform, and used to overwrite the given paths within the build environment.
+
+The default value of this option includes [paths from popular packages](configuration.md#configuration-file).
+
+Platform-specific environment variables are also available:<br/>
+ `CIBW_XBUILD_FILES_ANDROID`
+
+#### Examples
+
+!!! tab examples "pyproject.toml"
+
+    ```toml
+    [tool.cibuildwheel.xbuild-files]
+    package1 = ["some/header.h", "some/library.a"]
+    package2 = ["other/header.h"]
+    ```
+
+!!! tab examples "Environment variables"
+
+    ```yaml
+    CIBW_XBUILD_FILES: "package1: some/header.h some/library.a; package2: other/header.h"
+    ```
+
+
 ### `repair-wheel-command` {: #repair-wheel-command env-var toml}
 > Execute a shell command to repair each built wheel
 
 Default:
 
 - on Linux: `'auditwheel repair -w {dest_dir} {wheel}'`
+- on Windows: `'delvewheel repair -w {dest_dir} -v {wheel}'`
 - on macOS: `'delocate-wheel --require-archs {delocate_archs} -w {dest_dir} -v {wheel}'`
-- on Android: There is no default command, but cibuildwheel will add `libc++` to the
-  wheel if anything links against it. Setting a command will replace this behavior.
+- on Android: `'auditwheel repair --ldpaths {ldpaths} -w {dest_dir} {wheel}'`
 - on Pyodide: You can use `pyodide auditwheel repair --libdir /path/to/libraries --output-dir {dest_dir} {wheel}` command to repair the wheel.
   Unlike other platforms, this command is not set by default as you need to explicitly
   specify the library directory. You might not want to use the libraries in the system
@@ -934,11 +971,15 @@ Default:
 A shell command to repair a built wheel by copying external library dependencies into the wheel tree and relinking them.
 The command is run on each built wheel (except for pure Python ones) before testing it.
 
+!!! note
+    Since cibuildwheel 4.0, `delvewheel` is the default `repair-wheel-command` on Windows, so extension-module DLLs are bundled automatically. If a wheel has a platform tag but contains no extension module (for example, a package that sets a platform tag but ships a pre-built DLL itself), `delvewheel` may error. In that case, set `repair-wheel-command = ""` to skip the repair step.
+
 The following placeholders must be used inside the command and will be replaced by cibuildwheel:
 
 - `{wheel}` for the absolute path to the built wheel
 - `{dest_dir}` for the absolute path of the directory where to create the repaired wheel
 - `{delocate_archs}` (macOS only) comma-separated list of architectures in the wheel.
+- `{ldpaths}` (Android only) colon-separated list of directories to search for external libraries, set by cibuildwheel to include any necessary locations in the NDK. You can add more directories by appending them with a colon separator after the placeholder, or by setting the `AUDITWHEEL_LD_LIBRARY_PATH` environment variable.
 
 You can use the `{package}` or `{project}` placeholders in your `repair-wheel-command` to refer to the package being built or the project root, respectively.
 
@@ -947,24 +988,14 @@ The command is run in a shell, so you can run multiple commands like `cmd1 && cm
 Platform-specific environment variables are also available:<br/>
 `CIBW_REPAIR_WHEEL_COMMAND_MACOS` | `CIBW_REPAIR_WHEEL_COMMAND_WINDOWS` | `CIBW_REPAIR_WHEEL_COMMAND_LINUX` | `CIBW_REPAIR_WHEEL_COMMAND_ANDROID` | `CIBW_REPAIR_WHEEL_COMMAND_IOS` | `CIBW_REPAIR_WHEEL_COMMAND_PYODIDE`
 
-!!! tip
-    cibuildwheel doesn't yet ship a default repair command for Windows.
-
-    **If that's an issue for you, check out [delvewheel]** - a new package that aims to do the same as auditwheel or delocate for Windows.
-
-    Because delvewheel is still relatively early-stage, cibuildwheel does not yet run it by default. However, we'd recommend giving it a try! See the examples below for usage.
-
-    [Delvewheel]: https://github.com/adang1345/delvewheel
-
 #### Examples
 
 !!! tab examples "pyproject.toml"
 
     ```toml
-    # Use delvewheel on windows
+    # Don't repair Windows wheels
     [tool.cibuildwheel.windows]
-    before-build = "pip install delvewheel"
-    repair-wheel-command = "delvewheel repair -w {dest_dir} {wheel}"
+    repair-wheel-command = ""
 
     # Don't repair macOS wheels
     [tool.cibuildwheel.macos]
@@ -992,9 +1023,8 @@ Platform-specific environment variables are also available:<br/>
 !!! tab examples "Environment variables"
 
     ```yaml
-    # Use delvewheel on windows
-    CIBW_BEFORE_BUILD_WINDOWS: "pip install delvewheel"
-    CIBW_REPAIR_WHEEL_COMMAND_WINDOWS: "delvewheel repair -w {dest_dir} {wheel}"
+    # Don't repair Windows wheels
+    CIBW_REPAIR_WHEEL_COMMAND_WINDOWS: ""
 
     # Don't repair macOS wheels
     CIBW_REPAIR_WHEEL_COMMAND_MACOS: ""

docs/platforms.md

@@ -1,5 +1,6 @@
 ---
 title: Platforms
+ref: platforms
 ---
 # Platforms
 
@@ -219,13 +220,9 @@ It also requires the following commands to be on the `PATH`:
 
 Android builds will honor the `ANDROID_API_LEVEL` environment variable to set the
 minimum supported [API level](https://developer.android.com/tools/releases/platforms)
-for generated wheels. This will default to the minimum API level of the selected Python
-version.
-
-If the [`repair-wheel-command`](options.md#repair-wheel-command) adds any libraries to
-the wheel, then `ANDROID_API_LEVEL` must be at least 24. This is already the default
-when building for Python 3.14 and later, but you may need to set it when building for
-Python 3.13.
+for generated wheels. This defaults to 24, which is supported by [99% of active
+devices](https://dl.google.com/android/studio/metadata/distributions.json), and is the first
+version to support RUNPATH, which auditwheel needs in order to graft external libraries.
 
 ### Build frontend support
 

docs/setup.md

@@ -1,5 +1,6 @@
 ---
 title: 'Getting started'
+ref: setup
 ---
 
 # Getting started

docs/working-examples.md

@@ -1,5 +1,6 @@
 ---
 title: Working examples
+ref: working-examples
 ---
 
 <!-- START bin/projects.py -->
@@ -40,8 +41,8 @@ title: Working examples
 | [OpenSpiel][]                     | ![github icon][] | ![apple icon][] ![linux icon][] | OpenSpiel is a collection of environments and algorithms for research in general reinforcement learning and search/planning in games. |
 | [aiortc][]                        | ![github icon][] | ![apple icon][] ![linux icon][] | WebRTC and ORTC implementation for Python using asyncio. |
 | [Dependency Injector][]           | ![travisci icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Dependency injection framework for Python, uses Windows TravisCI |
-| [UltraJSON][]                     | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Ultra fast JSON decoder and encoder written in C with Python bindings |
 | [CTranslate2][]                   | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Includes libraries from the [Intel oneAPI toolkit](https://www.intel.com/content/www/us/en/developer/tools/oneapi/base-toolkit.html) and CUDA kernels compiled for multiple GPU architectures. |
+| [UltraJSON][]                     | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Ultra fast JSON decoder and encoder written in C with Python bindings |
 | [pyzmq][]                         | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] ![android icon][] | Python bindings for zeromq, the networking library. Uses Cython on CPython and CFFI on PyPy. ARM wheels for linux are built natively on GitHub Actions.  |
 | [tinyobjloader][]                 | ![azurepipelines icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Tiny but powerful single file wavefront obj loader |
 | [Implicit][]                      | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Includes GPU support for linux wheels |
@@ -81,8 +82,8 @@ title: Working examples
 | [python-rapidjson][]              | ![travisci icon][] ![gitlab icon][] | ![windows icon][] ![linux icon][] | Python wrapper around rapidjson |
 | [pybind11 python_example][]       | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] ![pyodide icon][] | Example pybind11 module built with a Python-based build system |
 | [python-snappy][]                 | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Python bindings for the snappy google library |
-| [abess][]                         | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | A fast best-subset selection library. It uses cibuildwheel to build a large project with C++ extensions. |
 | [Confluent client for Kafka][]    | ![travisci icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | setup in `tools/wheels/build-wheels.bat` |
+| [abess][]                         | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | A fast best-subset selection library. It uses cibuildwheel to build a large project with C++ extensions. |
 | [jq.py][]                         | ![travisci icon][] | ![apple icon][] ![linux icon][] | Python bindings for jq |
 | [cyvcf2][]                        | ![github icon][] | ![apple icon][] ![linux icon][] | cython + htslib == fast VCF and BCF processing |
 | [matrixprofile][]                 | ![travisci icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | A Python 3 library making time series data mining tasks, utilizing matrix profile algorithms, accessible to everyone. |
@@ -109,8 +110,8 @@ title: Working examples
 | [cf-units][]                      | ![github icon][] | ![apple icon][] ![linux icon][] | Units of measure as required by the Climate and Forecast (CF) Metadata Conventions |
 | [etebase-py][]                    | ![travisci icon][] | ![linux icon][] | Python bindings to a Rust library using `setuptools-rust`, and `sccache` for improved speed. |
 | [SiPM][]                          | ![github icon][] | ![apple icon][] ![linux icon][] | High performance library for SiPM detectors simulation using C++17, OpenMP and AVX2 intrinsics. |
-| [numpythia][]                     | ![github icon][] | ![apple icon][] ![linux icon][] | The interface between PYTHIA and NumPy |
 | [aalink][]                        | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | Async Python interface for Ableton Link. |
+| [numpythia][]                     | ![github icon][] | ![apple icon][] ![linux icon][] | The interface between PYTHIA and NumPy |
 | [pyjet][]                         | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | The interface between FastJet and NumPy |
 | [ril][]                           | ![github icon][] | ![windows icon][] ![apple icon][] ![linux icon][] | A python binding to Rust Imaging library using maturin and Pyo3, utilizes Github Action cache to improve speed. Builds abi3 wheels. |
 | [GSD][]                           | ![github icon][] | ![apple icon][] ![linux icon][] ![windows icon][] | Cython and NumPy project with 64-bit wheels. |
@@ -151,8 +152,8 @@ title: Working examples
 [OpenSpiel]: https://github.com/google-deepmind/open_spiel
 [aiortc]: https://github.com/aiortc/aiortc
 [Dependency Injector]: https://github.com/ets-labs/python-dependency-injector
-[UltraJSON]: https://github.com/ultrajson/ultrajson
 [CTranslate2]: https://github.com/OpenNMT/CTranslate2
+[UltraJSON]: https://github.com/ultrajson/ultrajson
 [pyzmq]: https://github.com/zeromq/pyzmq
 [tinyobjloader]: https://github.com/tinyobjloader/tinyobjloader
 [Implicit]: https://github.com/benfred/implicit
@@ -192,8 +193,8 @@ title: Working examples
 [python-rapidjson]: https://github.com/python-rapidjson/python-rapidjson
 [pybind11 python_example]: https://github.com/pybind/python_example
 [python-snappy]: https://github.com/intake/python-snappy
-[abess]: https://github.com/abess-team/abess
 [Confluent client for Kafka]: https://github.com/confluentinc/confluent-kafka-python
+[abess]: https://github.com/abess-team/abess
 [jq.py]: https://github.com/mwilliamson/jq.py
 [cyvcf2]: https://github.com/brentp/cyvcf2
 [matrixprofile]: https://github.com/matrix-profile-foundation/matrixprofile
@@ -220,8 +221,8 @@ title: Working examples
 [cf-units]: https://github.com/SciTools/cf-units
 [etebase-py]: https://github.com/etesync/etebase-py
 [SiPM]: https://github.com/EdoPro98/SimSiPM
-[numpythia]: https://github.com/scikit-hep/numpythia
 [aalink]: https://github.com/artfwo/aalink
+[numpythia]: https://github.com/scikit-hep/numpythia
 [pyjet]: https://github.com/scikit-hep/pyjet
 [ril]: https://github.com/Cryptex-github/ril-py
 [GSD]: https://github.com/glotzerlab/gsd

examples/azure-pipelines-minimal.yml

@@ -6,7 +6,7 @@ jobs:
     - bash: |
         set -o errexit
         python3 -m pip install --upgrade pip
-        pip3 install cibuildwheel==4.0.0rc1
+        pip3 install cibuildwheel==4.0.0rc2
       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==4.0.0rc1
+        python3 -m pip install cibuildwheel==4.0.0rc2
       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==4.0.0rc1
+        pip install cibuildwheel==4.0.0rc2
       displayName: Install dependencies
     - bash: cibuildwheel --output-dir wheelhouse .
       displayName: Build wheels

examples/circleci-minimal.yml

@@ -11,7 +11,7 @@ jobs:
       - run:
           name: Build the Linux wheels.
           command: |
-            python3 -m pip install --user cibuildwheel==4.0.0rc1
+            python3 -m pip install --user cibuildwheel==4.0.0rc2
             cibuildwheel --output-dir wheelhouse
       - store_artifacts:
           path: wheelhouse/
@@ -28,7 +28,7 @@ jobs:
       - run:
           name: Build the Linux aarch64 wheels.
           command: |
-            python3 -m pip install --user cibuildwheel==4.0.0rc1
+            python3 -m pip install --user cibuildwheel==4.0.0rc2
             python3 -m cibuildwheel --output-dir wheelhouse
       - store_artifacts:
           path: wheelhouse/
@@ -44,7 +44,7 @@ jobs:
           name: Build the OS X wheels.
           command: |
             sudo softwareupdate --install-rosetta --agree-to-license  # for x86_64/universal2 tests
-            pip3 install cibuildwheel==4.0.0rc1
+            pip3 install cibuildwheel==4.0.0rc2
             cibuildwheel --output-dir wheelhouse
       - store_artifacts:
           path: wheelhouse/

examples/github-deploy.yml

@@ -53,7 +53,7 @@ jobs:
           persist-credentials: false
 
       - name: Build wheels
-        uses: pypa/cibuildwheel@v4.0.0rc1
+        uses: pypa/cibuildwheel@v4.0.0rc2
         env:
           CIBW_PLATFORM: ${{ matrix.platform || 'auto' }}
           CIBW_ARCHS: ${{ matrix.archs || 'auto' }}

examples/github-minimal.yml

@@ -17,7 +17,7 @@ jobs:
           persist-credentials: false
 
       - name: Build wheels
-        uses: pypa/cibuildwheel@v4.0.0rc1
+        uses: pypa/cibuildwheel@v4.0.0rc2
         # env:
         #   CIBW_SOME_OPTION: value
         #   ...

examples/github-pipx.yml

@@ -17,7 +17,7 @@ jobs:
           persist-credentials: false
 
       - name: Build wheels
-        run: pipx run cibuildwheel==4.0.0rc1
+        run: pipx run cibuildwheel==4.0.0rc2
 
       - uses: actions/upload-artifact@v4
         with:

examples/github-with-qemu.yml

@@ -23,7 +23,7 @@ jobs:
           platforms: all
 
       - name: Build wheels
-        uses: pypa/cibuildwheel@v4.0.0rc1
+        uses: pypa/cibuildwheel@v4.0.0rc2
         env:
           # configure cibuildwheel on Linux to build native archs ('auto'),
           # and to split the remaining architectures between the x86_64 and