Release Notes

This is the list of changes to scikit-build between each release. For full details, see the commit logs at

Next Release

We are hard at work on the next generation of scikit-build scikit-build-core, which will eventually replace the backend here. We are also continuing to fix bugs, make improvements, and backport changes here.

Scikit-build 0.18.0

This release bumps the minimum required CMake to 3.5 and supports CPython 3.13.

Bug fixes

  • Support MSVC 17.10 in #1081

  • CMake 3.5+ requirement in #1095

  • Support CPython 3.13 with windows lib finding fix in #1094

  • Don’t die on PermissionError during chmod by @mweinelt in #1073

  • Remove usage of deprecated distutils in cmake files by @hmaarrfk in #1032

  • Use first available option for vswhere output by @ZzEeKkAa in #1030


Fedora CI


  • Clean up pylint in #1017

  • Fix mypy type ignores for new setuptools types in #1082

  • Move to Ruff-format in #1035

  • Remove pkg_resources and test command in #1014

  • Ruff moved to astral-sh in #1007

  • Target-version no longer needed by Black or Ruff in #1008

  • Update ruff and fix warnings in #1060

  • Use 2x faster black mirror in #1021

  • Group dependabot updates in #1054

  • macos-latest is changing to macos-14 ARM runners in #1083

  • Skip win PyPy PEP 518 in #1091

Scikit-build 0.17.6

A small fix release with some new platforms and better testing, including CPython 3.12.0b1.

Bug fixes


  • Tests now pass on CPython 3.12.0b1 in #879.

  • Tests no longer use pytest-virtualenv in #879.

  • isolated marker now includes test_distribution tests in #879.

  • Tests avoid incorrect get_map match by @keszybz in #990.

  • Fedora testing fix by @LecrisUT in #986 and #938.


  • Docs improvements in #979.

Scikit-build 0.17.5

A small fix release fixing the passing on of generator specific arguments. This fixes some cases where the Ninja generator was found but then was unable to build. NetBSD was reported to work, so was added to the BSD’s supported.

Bug fixes

  • Generator args were missing for actual compile in #975.

  • Add support for netbsd & pyodide (future) in #977.

Scikit-build 0.17.4

A followup fix to the issue 0.17.3 tried to fix. We now have a method to manually test downstream packages, too.

Bug fixes

  • Make sure include dir is found even if the lib is not present in #974.

Scikit-build 0.17.3

A small release related to PYTHON_LIBRARY handling changes in 0.17.2; scikit-build 0.17.3 returns an empty string from get_python_library if no Python library is present (like on manylinux), where 0.17.2 returned None, and previous versions returned a non-existent path. Note that adding REQUIRED to find_package(PythonLibs will fail, but it is incorrect (you must not link to and was really just injecting a non-existent path before.

Bug fixes

  • Keep get_python_library return type string if python lib non-existing for now in #959.

  • Avoid ‘not found’ warning if libs are not found by FindPythonExtensions in #960.

  • FindNumPy should not call FindPythonLibs in #958.

Scikit-build 0.17.2

Another small release with fixes for non-MSVC Windows platforms.

Bug fixes

  • RPM spec fix by @LecrisUT in #937.

  • Validate value before returning library path by @dlech in #942.

  • Only add Python_LIBRARY on Windows MSVC in #943 and #944.

  • Slightly nicer traceback for failed compiler in #947.


  • Hide a few warnings that are expected in #948.

Scikit-build 0.17.1

This is a small release fixing a few bugs; the primary one being a change that was triggering a bug in older FindPython. The unused variable messages have been deactivated to simplify output, as well.

Bug fixes

  • Older (<3.24) CMake breaks when lib specified in #932.

  • An error output was missing formatting in #931.

  • Make empty CMAKE_OSX_DEPLOYMENT_TARGET a warning (bug in conda-forge’s clang activation fixed upstream) in #934.

  • Remove unused variable warnings by in #930.


Scikit-build 0.17.0

A lot of bug fixes are present in this release, focusing on Windows, PyPy, and cross compiling. We’ve also improved the compatibility with default setuptools behaviors a little, and enabled some things that were previously unavailable, like overriding the build type via the cmake argument environment variables. We’ve expanded our CI matrix to include Windows and macOS PyPy and some Fortran tests on Linux. This release requires Python 3.7+.

Bug fixes

  • Match setuptools behavior for include_package_data default. by @vyasr in #873.

  • Misc. fixes for F2PY and PythonExtensions modules by @benbovy in #495.

  • Provide more useful error if user provides CMAKE_INSTALL_PREFIX by @vyasr in #872.

  • Stop assuming that .pyx files are in the same directory as CMakeLists.txt by @vyasr in #871.

  • Allow build type overriding in #902.

  • Detect PyPy library correctly on Windows by user:gershnik in #904.

  • Include library for FindPython for better Windows cross-compiles in #913. Thanks to user:maxbachmann for testing.

  • Fix logic for default generator when cross-compiling for ARM on Windows in #917 by @dlech.

  • Use f2py’s get_include if present in #877.

  • Fix support for cross-compilation exception using targetLinkLibrariesWithDynamicLookup by @erykoff in #901.

  • Treat empty MACOSX_DEPLOYMENT_TARGET as if it was unset in #918.


  • Add hello fortran sample package + tests by @benbovy in #493.

  • Add sdist check & fix in #906.

  • Fix some setuptools types in #888.

  • Add PyPy Win & macOS to the CI in #907.

  • Add tests for Python 3.12 Linux alphas in #922.


  • Drop Python 3.6 in #862.

  • Move building backend to hatchling in #870.

  • Avoid mutating function input parameters in #899.

  • Use _compat/typing name in #869.

Scikit-build 0.16.7

This is expected to be the final release series supporting Python 3.6. 0.17 will require Python 3.7+ and start removing deprecated functionality.

  • Added SKBUILD_GNU_SKIP_LOCAL_SYMBOL_EXPORT_OVERRIDE to disable script in #848, thanks to @aaron-bray and @vyasr.

  • Address a new warning from setuptools in our test suite in #859.

  • Move to using Ruff, update to Black 23, and use Flynt to move more code to f-strings.

Scikit-build 0.16.6

  • Fix a discovery regression in 0.16.5 when a cmake folder or was present in #848.

  • Correct an issue in the tests where a generator wasn’t expanded into a list in #850.

Scikit-build 0.16.5

  • Use cmake module if installed over system installs in #839.

  • Support setting of -DCMAKE_SYSTEM_PROCESSOR if passed for selecting an arch, useful for cross compiling on conda-forge in #843.

  • Fixed a rare encoded error output string on Windows in #842.

  • Better granularity in extras in #838.

  • Add test markers for nosetuptoolsscm and isolated (helpful for package distributions building scikit-build itself like conda) in #837.

Scikit-build 0.16.4

This releases backports additions for Windows ARM cross-compiling via cibuildwheel from scikit-build-core 0.1.4.

  • Initial experimental support for Windows ARM cross-compile in #824 and #818

  • Replace mailing list with GitHub Discussions board in #823

  • Some CI updates in #811 and #812

Scikit-build 0.16.3

This release fixes logging issues using setuptools 65.6+ affecting our tests. Pytest 7.2+ is now supported. <command> and setup_requires are deprecated, and tests are marked as such.

  • Fix typo in usage.rst in #795, thanks to @chohner.

  • Support pytest 7.2+ in #801.

  • Change warning filtering in #802.

  • Handle logging changes in setuptools 65.6+ in #807.

  • Add deprecated markers to some tests in #807.

  • Allow known warnings to show up in the tests #807.

Scikit-build 0.16.2

This addresses one more small regression with the FindPython change from 0.16.0 that was affecting conda. #793.

Scikit-build 0.16.1

This was a quick patch release that fixed a missing Python requires setting and some missing files #790, and addressed a warning from setuptools in the tests.

Scikit-build 0.16.0

This release adds support for Python 3.11 and removes support for Python 2.7 and 3.5 (#688). Testing and static checking improved, including being fully statically typed internally (though setuptools is not fully typed, so it is of limited use).

All deprecated setuptools/distutils features are also deprecated in scikit-build, like the test command, easy_install, etc. Editable mode is still unsupported. Python 3.6 support is deprecated. Older versions of CMake (<3.15) are not recommended; a future version will remove support for older CMake’s (along with providing a better mechanism for ensuring a proper CMake is available). If you need any of these features, please open or find an issue explaining what and why you need something.

New Features

  • Cython module now supports FindPython mode. #743

  • PyPy is discovered without extra settings in FindPython mode #744

Bug fixes

  • FindPython mode uses a new path specification, should help make it usable. #774

  • Better flushing and output streams for more consistent output ordering. #781


  • scikit-build mailing list transitioned to the scikit-build GitHub Discussions board. See #800. * Transitioning away from the mailing list and adopting the GitHub Discussions will provide a more integrated platform enabling us to more effectively engage with the community. * After sending a last message describing the transition, the mailing list was updated to be read-only and the welcome message was updated to redirect visitor toward the Discussions board.

Scikit-build 0.15.0

This release is the final (again) release for Python < 3.6 and MSVC<2017. Support for FindPython from CMake 3.12+ was added, including FindPython2. Support for Cygwin added.

New Features

Bug fixes

  • Fixed issue with distutils usage in Python 3.10. Thanks to @SuperSandro2000 for the contribution in #700.

Scikit-build 0.14.1

This release fixes a regression, and reverts a fix in 0.14.0. Some changes made to CI to fix recent removals.

Bug fixes

  • Fix issue with SKBUILD_CONFIGURE_OPTIONS not being read.

  • Reverted manifest install changes.

Scikit-build 0.14.0

This is the final release for Python < 3.6 and MSVC<2017.

New Features

  • Add support for --install-target scikit-build command line option. And cmake_install_target in Allows providing an install target different than the default install. Thanks @phcerdan for the contribution. See #477.

Bug fixes

  • The manifest install location computation was fixed. Thanks @kratsg for the contribution in #682. (Reverted in 0.14.1)

  • Byte-compilation was skipped due to a missing return. Thanks @pekkarr in #678.

  • Packages can now be computed from the same shared collections, before this could confuse Scikit-build. Thanks @vyasr in #675.

  • Fixed library detection for PyPy 3.9. Thanks @rkaminsk in #673.


  • Scikit-build now uses pyproject.toml and setuptools_scm to build. If you are packaging scikit-build itself, you might need to update your requirements. See #634.

  • The codebase is now formatted with Black. #665

Scikit-build 0.13.1

This release fixes two bugs affecting Windows. Users should use "ninja; platform_system!='Windows", at least for now, since MSVC ships with Ninja, and that Ninja is better at finding the matching MSVC than the Python package is. Including it may slow down the search and force the IDE generator instead, but will at least no longer discover GCC instead.

Bug fixes

  • On Windows, don’t let Ninja find something other than what it’s supposed to look for. Ensure the Ninja package is used for the search, just like normal runs, if installed. #652.

  • Do not throw an error when printing info and a logger is disconnected. #652

Scikit-build 0.13.0

This is likely one of the final releases to support Python 2.7 and 3.5; future releases will likely target at least Python 3.6+ and MSCV 2017+.

If you are using scikit-build via pyproject.toml, please remember to include setuptools and wheel. A future version of scikit-build may remove the setuptools install-time hard requirement.

New Features

  • CMake module Cython now uses Cython default arguments. This no longer adds --no-docstrings in Release and MinSizeRel builds, so Cython docstrings are now retained by default. Additionally, --embed-positions is no longer added to Debug and RelWithDebInfo builds. Users can enable these and other Cython arguments via the option CYTHON_FLAGS. See #518 and #519, thanks to @bdice for the improvement.

  • Experimental support for ARM64 on Windows. Thanks to @gaborkertesz-linaro in #612.

  • Support for MSVC 2022. Thanks to @tttapa for the contribution in #627.

  • Support the modern form of target_link_libraries, via SKBUILD_LINK_LIBRARIES_KEYWORD (somewhat experimental). Thanks to @maxbachmann in #611.

Bug fixes

  • Update the Ninja path if using the ninja package. This fixes repeated isolated builds. Further path inspection and updates for isolated builds may be considered in the future. #631, thanks to @RUrlus and @segevfiner for help in tracking this down.

  • Allow OpenBSD to pass the platform check (untested). See #586.

  • Avoid forcing the min macOS version. Behaviour is now inline with setuptools. Users should set MACOSX_DEPLOYMENT_TARGET when building (automatic with cibuildwheel), otherwise you will get the same value Python was compiled with. Note: This may seem like a regression for PyPy until the next release (7.3.8), since it was compiled with 10.7, which is too old to build with on modern macOS - manually set MACOSX_DEPLOYMENT_TARGET (including setting it if unset in your for PyPy until 7.3.8. #607

  • Fix logging issue when using Setuptools 60.2+. #623

  • MacOS cross compiling support fix (for conda-forge) for built-in modules. Thanks to @isuruf for the contribution in #622.

  • Better detection of the library path, fixes some issues with PyPy. Thanks to @rkaminsk for the contribution in #620 and #630. PyPy is now part of our testing matrix as of #624. Also @robtaylor in #632.

  • Fixed issue when cross-compiling on conda-forge (probably upstream bug, but easy to avoid). #646.

Scikit-build 0.12.0

The scikit-build GitHub organization welcomes @henryiii and @mayeut as core contributors and maintainers. Both are also maintainers of cibuildwheel.

@henryiii is a pybind11 and pypa/build maintainer, has been instrumental in adding Apple Silicon support, adding support for Visual Studio 2019, updating the Continuous Integration infrastructure, as well as helping review & integrate contributions, and addressing miscellaneous issues. Additionally, @henryiii has worked on an example project to build with pybind11 and scikit-build.

@mayeut is a manylinux maintainer and focused his effort on updating the cmake-python-distributions and ninja-python-distributions so that the corresponding wheels are available on all supported platforms including Apple Silicon and all flavors of manylinux.

New Features

  • Support Apple Silicon, including producing Universal2 wheels (#530) and respecting standard setuptools cross-compile variables (#555). Thanks to @YannickJadoul for the contributions.

  • Support MSVC 2019 without having to run it with the MSVC activation variables, just like 2017 and earlier versions. Thanks to @YannickJadoul for the contribution in #526.

Bug fixes

  • Support -A and -T internally when setting up MSVC generators. Architecture now always passed through -A to MSVC generators. Thanks @YannickJadoul for the contribution. See #557 and #536.

  • Fixed a regression that caused setuptools to complain about unknown setup option (cmake_process_manifest_hook). Thanks @Jmennius for the contribution. See #498.

  • If it applies, ensure generator toolset is used to configure the project. Thanks @YannickJadoul for the contributions. See #526.

  • Read CYTHON_FLAGS where needed, instead of once, allowing the user to define multiple modules with different flags. Thanks @oiffrig for the contributions in #536.

  • Avoid an IndexError if prefix was empty. Thanks @dfaure for the contributions in #522.



  • Improve and simplify Continuous Integration infrastructure.

    • Support nox for running the tests locally. See #540.

    • Use GitHub Actions for Continuous Integration and remove use of scikit-ci, tox, TravisCI, AppVeyor and CircleCI. See #549, #551 and #552.

    • Add support for testing against Python 3.10. See #565.

    • Style checking handled by pre-commit. See #541.

    • Check for misspellings adding GitHub Actions workflow using codespell. See #541.

  • Fix linting error F522 reported with flake8 >= 3.8.x. Thanks @benbovy for the contributions. See #494.

  • Fix regex in tests to support Python 3.10. Thanks @mgorny for the contributions in #544.

Scikit-build 0.11.1

Bug fixes


  • Fix link in Conda: Step-by-step release guide available in Making a release section.

Scikit-build 0.11.0

New Features

  • Add a hook to process the cmake install manifest building the wheel. The hook function can be specified as an argument to the setup() function. This can be used e.g. to prevent installing cmake configuration files, headers, or static libraries with the wheel. Thanks @SylvainCorlay for the contribution. See #473.

  • Add support for passing CMake configure options like -DFOO:STRING:bar as global setuptools or pip options.

  • Add support for building project using PyPy or PyPy3. See See #407.

  • Add support for OS/400 (now known as IBM i). Thanks @jwoehr for the contribution. See #444.

  • Display CMake command used to configure the project. Thanks @native-api for the contribution. See #443.

  • CMake modules:

    • Improve CMake module F2PY adding add_f2py_target() CMake function allowing to generate *-f2pywrappers.f and *module.c files from *.pyf files. Thanks @xoviat for the contribution.

    • Update CMake module PythonExtensions adding add_python_library() and add_python_extension(). Thanks @xoviat for the contribution.

Bug fixes

  • Fix python 2.7 installation ensuring setuptools < 45 is required. See #478.

  • Fix unclosed file resource in skbuild.cmaker.CMaker.check_for_bad_installs(). Thanks @Nic30 for the suggestion. See #429.

  • Update CMake module PythonExtensions:

    • Ensure correct suffix is used for compiled python module on windows. See #383.

    • Fix warning using EXT_SUFFIX config variable instead of deprecated SO variable. See #381.

  • Honor the MACOSX_DEPLOYMENT_TARGET environment variable if it is defined on macOS. Thanks @certik for the contribution. See #441.

  • Fix CMake module F2PY to ensure the f2py executable specific to the python version being used is found. See #449. Thanks @bnavigator for the contribution.

  • Replace platform.linux_distribution() which was removed in Python 3.8 by a call to This adds the distro package as dependency. See #458. Thanks @bnavigator for the contribution.


  • Add notes section to the For maintainers top-level category that includes a comparison between sysconfig and distutils.sysconfig modules.

  • Remove obsolete comment in See #439. Thanks @isuruf


  • Update initialize_git_repo_and_commit to prevent signing message on system with commit signing enabled globally.

Scikit-build 0.10.0

New Features

  • Improve message displayed when discovering a working environment for building projects. For example, instead of displaying -- Trying "Ninja" generator, it now displays a message like -- Trying "Ninja (Visual Studio 15 2017 Win64 v140)" generator.

Bug fixes

  • Checking generator candidates can now handle handle paths and binaries with spaces, so that --cmake-executable "C:/Program Files (x86)/cmake/cmake.exe" works as expected. Contributed by @jokva. See #400.

  • Fix sdist command to ensure symlinks in original source tree are maintained. Contributed by @anibali. See #401.

  • Ensure use of bdist_egg or bdist_rpm commands trigger build using cmake.

  • Fix default value returned by skbuild.constants.skbuild_plat_name() on macOS. See #417.

Internal API



  • Introduce check_sdist_content() and fix tests that are checking content of sdist to account for changes introduced in Python 3.8 and backported to python 2.7, 3.6 and 3.7. The changes introduced in python/cpython#9419 adds directory entries to ZIP files created by distutils. Thanks @anibali for the contribution. See #404.

  • Fix check_wheel_content() to consider changes in 0.33.1 < wheel.__version__ < 0.33.4 where directory entries are included when building wheel. See pypa/wheel#294 <>.

  • Fix reporting of AssertionError raised in check_wheel_content() function by relocating the source code into a dedicated module tests.pytest_helpers and by adding a configuration file registering it for pytest assertion rewriting. See and #403.

  • Fix test_generator_selection when building with “Visual C++ for Python 2.7” installed for all users. This addresses failure associated with win_c_compilervs2008cxx_compilervs2008python2.7 when running test in scikit-build-feedstock where “Visual C++ for Python 2.7” is installed using (vcpython27 chocolatey package.

  • Continuous Integration

    • Add support for Azure Pipelines for Python 3.7 32-bit and 64-bit

    • AppVeyor: Disable test for Python 3.7 32-bit and 64-bit.

    • CircleCI: Update version of docker images from jessie to stretch. This addresses issue circleci/circleci-images#370.

    • TravisCI: Remove obsolete Python 3.4 testing. It reached end-of-life on March 18 2019.

Scikit-build 0.9.0

New Features

  • Add support for building distutils based extensions associated with ext_modules setup keyword along side skbuild based extensions. This means using build_ext command (and associated --inplace argument) is supported. Thanks @Erotemic for the contribution. See #284.

Bug fixes

  • Fix build of wheels if path includes spaces. See issue #375. Thanks @padraic-padraic for the contribution.

  • Ensure wheel platform name is correctly set when providing custom CMAKE_OSX_DEPLOYMENT_TARGET and CMAKE_OSX_ARCHITECTURES values are provided. Thanks @nonhermitian for the contribution. See #377.

  • Fix testing with recent version of pytest by updating the pytest-runner requirements expression in Thanks @mackelab for the contribution.

Scikit-build 0.8.1

Bug fixes

  • Fix bdist_wheel command to support wheel >= 0.32.0. Thanks @fbudin69500 for reporting issue #360.


  • Fix updating use of Path.files() and requiring>=11.5.0.

Scikit-build 0.8.0

New Features

  • Introduced skbuild.constants.CMAKE_DEFAULT_EXECUTABLE to facilitate distribution of scikit-build in package manager like Nixpkgs where all paths to dependencies are hardcoded. Suggested by @FRidh.

  • Setup keywords:

    • If not already set, zip_safe option is set to False. Suggested by @blowekamp.

  • Add support for --skip-generator-test when a generator is explicitly selected using --generator. This allows to speed up overall build when the build environment is known.

Bug fixes

  • Fix support for building project with CMake source directory outside of the directory. See #335 fixed by @massich.

  • Fix reading of .cmake files having any character not available in CP-1252 (the default code page on windows). See #334 fixed by @bgermann.

  • Fix parsing of macOS specific arguments like --plat-name macosx-X.Y-x86_64 and -DCMAKE_OSX_DEPLOYMENT_TARGET:STRING=X.Y and ensure that the ones specified as command line arguments override the default values or the one hard-coded in the cmake_args setup keyword. Thanks @yonip for the help addressing #342.

  • Support case where relative directory set in package_dir has an ending slash. For example, specifying package_dir={'awesome': 'src/awesome/'}, is now properly handled.

  • Fix support for isolated build environment ensuring the CMake project is reconfigured when pip install -e . is called multiple times. See #352.



  • Add check_wheel_content utility function.

  • Skip test_setup_requires_keyword_include_cmake if running in conda test environment or if is not reachable. Suggested by @Luthaf.

  • Continuous Integration

    • TravisCI:

      • Remove testing of linux now covered by CircleCI, add testing for Python 3.5, 3.6 and 3.7 on macOS.

      • Ensure system python uses latest version of pip

    • AppVeyor, CircleCI: Add testing for Python 3.7

    • Remove uses of unneeded $<RUN_ENV> command wrapper. scikit-build should already take care of setting up the expected environment.

    • Always install up-to-date scikit-ci and scikit-ci-addons.

    • Simplify release process managing versioning with python-versioneer and update Making a release documentation.

Scikit-build 0.7.1


  • Fix description and classifier list in

  • Fix link in README.

Scikit-build 0.7.0

New Features

  • Faster incremental build by re-configuring the project only if needed. This was achieved by (1) adding support to retrieve the environment mapping associated with the generator set in the CMakeCache.txt file, (2) introducing a CMake spec file storing the CMake version as well as the the CMake arguments and (3) re-configuring only if either the generator or the CMake specs change. Thanks @xoviat for the contribution. See #301.

  • CMake modules:

    • CMake module PythonExtensions: Set symbol visibility to export only the module init function. This applies to GNU and MSVC compilers. Thanks @xoviat. See #299.

    • Add CMake module F2PY useful to find the f2py executable for building Python extensions with Fortran. Thanks to @xoviat for moving forward with the integration. Concept for the module comes from the work of @scopatz done in PyNE project. See #273.

    • Update CMake module NumPy setting variables NumPy_CONV_TEMPLATE_EXECUTABLE and NumPy_FROM_TEMPLATE_EXECUTABLE. Thanks @xoviat for the contribution. See #278.

  • Setup keywords:

    • Add support for cmake_languages setup keyword.

    • Add support for include_package_data and exclude_package_data setup keywords as well as parsing of See #315. Thanks @reiver-dev for reporting the issue.

    • Add support for cmake_minimum_required_version setup keyword. See #312. Suggested by @henryiii.

    • Install cmake if found in setup_requires list. See #313. Suggested by @henryiii.

  • Add support for --cmake-executable scikit-build command line option. Thanks @henryborchers for the suggestion. See #317.

  • Use _skbuild/platform-X.Y instead of _skbuild to build package. This allows to have a different build directory for each python version. Thanks @isuruf for the suggestion and @xoviat for contributing the feature. See #283.

  • Run cmake and develop command when command test is executed.

Bug fixes

  • Fix support of --hide-listing when building wheel.

  • CMake module Cython: Fix escaping of spaces associated with CYTHON_FLAGS when provided as command line arguments to the cython executable through CMake cache entries. See #265 fixed by @neok-m4700.

  • Ensure package data files specified in the setup() function using package_data keyword are packaged and installed.

  • Support specifying a default directory for all packages not already associated with one using syntax like package_dir={'':'src'} in Thanks @benjaminjack for reporting the issue. See #274.

  • Improve --skip-cmake command line option support so that it can re-generate a source distribution or a python wheel without having to run cmake executable to re-configure and build. Thanks to @jonwoodring for reporting the issue on the mailing list.

  • Set skbuild <version> as wheel generator. See PEP-0427 and #191.

  • Ensure is considered when generating source distribution. Thanks @seanlis for reporting the problem and providing an initial patch, and thanks @henryiii for implementing the corresponding test. See #260.

  • Support generation of source distribution for git repository having submodules. This works only for version of git >= 2.11 supporting the --recurse-submodules option with ls-files command.

Internal API

Python Support

  • Tests using Python 3.3.x were removed and support for this version of python is not guaranteed anymore. Support was removed following the deprecation warnings reported by version 0.31.0 of wheel package, these were causing the tests test_source_distribution and test_wheel to fail.


  • Speedup execution of tests that do not require any CMake language enabled. This is achieved by (1) introducing the test project hello-no-language, (2) updating test utility functions execute_setup_py and project_setup_py_test to accept the optional parameter disable_languages_test allowing to skip unneeded compiler detection in test project used to verify that the selected CMake generator works as expected, and (3) updating relevant tests to use the new test project and parameters.

    Overall testing time on all continuous integration services was reduced:

    • AppVeyor:

      • from ~16 to ~7 minutes for 64 and 32-bit Python 2.7 tests done using Visual Studio Express 2008

      • from more than 2 hours to ~50 minutes for 64 and 32-bit Python 3.5 tests done using Visual Studio 2015. Improvement specific to Python 3.x were obtained by caching the results of slow calls to distutils.msvc9compiler.query_vcvarsall (for Python 3.3 and 3.4) and distutils._msvccompiler._get_vc_env (for Python 3.5 and above). These functions were called multiple times to create the list of used in

    • CircleCI: from ~7 to ~5 minutes.

    • TravisCI: from ~21 to ~10 minutes.

  • Update maximum line length specified in flake8 settings from 80 to 120 characters.

  • Add prepend_sys_path utility function.

  • Ensure that the project directory is prepended to sys.path when executing test building sample project with the help of execute_setup_py function.

  • Add codecov config file for better defaults and prevent associated Pull Request checks from reporting failure when coverage only slightly changes.



  • Fix miscellaneous pylint warnings.

Scikit-build 0.6.1

Bug fixes

  • Ensure CMake arguments passed to scikit-build and starting with -DCMAKE_* are passed to the test project allowing to determine which generator to use. For example, this ensures that arguments like -DCMAKE_MAKE_PROGRAM:FILEPATH=/path/to/program are passed. See #256.


  • Update Making a release section including instructions to update README.rst with up-to-date pypi download statistics based on Google big table.

Scikit-build 0.6.0

New features

  • Improve py_modules support: Python modules generated by CMake are now properly included in binary distribution.

  • Improve developer mode support for py_modules generated by CMake.

Bug fixes

  • Do not implicitly install python modules when the beginning of their name match a package explicitly listed. For example, if a project has a package foo/ and a module, and only package foo was listed in, is not installed anymore.

  • CMake module targetLinkLibrariesWithDynamicLookup: Fix the caching of dynamic lookup variables. See #240 fixed by @blowekamp.


  • wheel: As suggested by @thewtex, unpinning version of the package by requiring >=0.29.0 instead of ==0.29.0 will avoid uninstalling a newer version of wheel package on up-to-date system.



  • Extend test_hello, test_setup, and test_sdist_hide_listing to (1) check if python modules are packaged into source and wheel distributions and (2) check if python modules are copied into the source tree when developer mode is enabled.

Internal API

Scikit-build 0.5.1

Bug fixes

  • Ensure file copied in “develop” mode have “mode bits” maintained.

Scikit-build 0.5.0

New features

  • If available, uses Ninja build system generator on all platforms. An advantages is that ninja automatically parallelizes the build based on the number of CPUs.

  • Automatically set the expected Visual Studio environment when Ninja or NMake Makefiles generators are used.

  • Support Microsoft Visual C++ Compiler for Python 2.7. See #216.

  • Update long signature: <LinkFlagsVar> is now optional

  • Add support for short signature: check_dynamic_lookup(<ResultVar>). See SimpleITK/SimpleITK#80.

Bug fixes

  • Fix scikit-build source distribution and add test. See #214 Thanks @isuruf for reporting the issue.

  • Support building extension within a virtualenv on windows. See #119.


  • hacking:


  • setuptools: As suggested by @mivade in #212, remove the hard requirement for ==28.8.0 and require version >= 28.0.0. This allows to “play” nicely with conda where it is problematic to update the version of setuptools. See pypa/pip#2751 and ContinuumIO/anaconda-issues#542.


  • Improve “push_dir” tests to not rely on build directory name. Thanks @isuruf for reporting the issue.

  • travis/install_pyenv: Improve MacOSX build time updating scikit-ci-addons

  • Add get_cmakecache_variables utility function.

Internal API


  • appveyor.yml:

  • Remove unused “on_failure: event logging” and “notifications: GitHubPullRequest”

  • Remove unused SKIP env variable

Scikit-build 0.4.0

New features

  • Add support for --hide-listing option

  • allow to build distributions without displaying files being included

  • useful when building large project on Continuous Integration service limiting the amount of log produced by the build

  • CMake module: skbuild/resources/cmake/FindPythonExtensions.cmake

  • Function python_extension_module: add support for module suffix

Bug fixes

  • Do not package python modules under “purelib” dir in non-pure wheel

  • CMake module: skbuild/resources/cmake/targetLinkLibrariesWithDynamicLookup.cmake:

  • Fix the logic checking for cross-compilation (the regression was introduced by #51 and #47

  • It configure the text project setting CMAKE_ENABLE_EXPORTS to ON. Doing so ensure the executable compiled in the test exports symbols (if supported by the underlying platform)



  • tests/samples: Simplify project removing unneeded install rules and file copy

  • Simplify continuous integration

  • Makefile:

  • Fix coverage target

  • Add docs-only target allowing to regenerate the Sphinx documentation without opening a new page in the browser.

Scikit-build 0.3.0

New features

  • Improve support for “pure”, “CMake” and “hybrid” python package

  • a “pure” package is a python package that have all files living in the project source tree

  • an “hybrid” package is a python package that have some files living in the project source tree and some files installed by CMake

  • a “CMake” package is a python package that is fully generated and installed by CMake without any of his files existing in the source tree

  • Add support for source distribution. See #84

  • Add support for setup arguments specific to scikit-build:

  • cmake_args: additional option passed to CMake

  • cmake_install_dir: relative directory where the CMake project being built should be installed

  • cmake_source_dir: location of the CMake project

  • Add CMake module FindNumPy.cmake

  • Automatically set package_dir to reasonable defaults

  • Support building project without CMakeLists.txt

Bug fixes

  • Fix dispatch of arguments to setuptools, CMake and build tool. See #118

  • Force binary wheel generation. See #106

  • Fix support for py_modules (6716723)

  • Do not raise error if calling “clean” command twice



  • Ensure each test run in a dedicated temporary directory

  • Add tests to raise coverage from 70% to 91%

  • Refactor CI testing infrastructure introducing CI drivers written in python for AppVeyor, CircleCI and TravisCI

  • Switch from nose to py.test

  • Relocate sample projects into a dedicated home:


  • Refactor commands introducing set_build_base_mixin and new_style

  • Remove unused code


PyCMake was created at SciPy 2014 in response to general difficulties building C++ and Fortran based Python extensions across platforms. It was renamed to “scikit-build” in 2016.