[FEA] Windows compatibility

[koopa31]

Hi,
First of all, thank you for that great work. I am currently using Cucim to accelerate morphological operations computation in the Napari plugin I developed.
I would like my plugin to be cross-platform, unfortunately, Cucim is not available for Windows. Is there a reason it has only been developed for Linux? If not, do you think it will be available on other platforms someday?
Thank you very much

[grlee77]

Here is a previous comment on ways of installing for Windows (without the cucim.clara I/O component):
#270 (comment)

see also #441, #270, #86

Given that this seems to be a popular request, it seems we may want to consider providing a separate wheel for the cucim.core/cucim.skimage component in a future release.

[wohali]

Here is a previous comment on ways of installing for Windows (without the cucim.clara I/O component): #270 (comment)

FYI this workaround does not appear to be working for me as of today, possibly because python/cucim/src/cucim/VERSION is a symlink to ../../VERSION which in turn is a symlink to ../../VERSION, resulting in this humorous error:

(hough-py3.12) C:\workspace\hough>pip install -e "git+https://github.com/rapidsai/cucim.git@v25.04.00#egg=cucim-cu12&subdirectory=python/cucim"
Obtaining cucim-cu12 from git+https://github.com/rapidsai/cucim.git@v25.04.00#egg=cucim-cu12&subdirectory=python/cucim
  Updating c:\users\joan\appdata\local\pypoetry\cache\virtualenvs\hough-stffmzkd-py3.12\src\cucim-cu12 clone (to revision v25.04.00)
  Running command git fetch -q --tags
  Running command git reset --hard -q 75b6d80c30bbb74846d036e9c577d830cd6da2c4
  Installing build dependencies ... done
  Checking if build backend supports build_editable ... done
  Getting requirements to build editable ... done
  Installing backend dependencies ... done
  Preparing editable metadata (pyproject.toml) ... error
  error: subprocess-exited-with-error

  × Preparing editable metadata (pyproject.toml) did not run successfully.
  │ exit code: 1
  ╰─> [114 lines of output]
      C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\config\_apply_pyprojecttoml.py:82: SetuptoolsDeprecationWarning: `project.license` as a TOML table is deprecated
      !!

              ********************************************************************************
              Please use a simple string containing a SPDX expression for `project.license`. You can also use `project.license-files`. (Both options available on setuptools>=77.0.0).

              By 2026-Feb-18, you need to update your project and remove deprecated calls
              or your builds will no longer be supported.

              See https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#license for details.
              ********************************************************************************

      !!
        corresp(dist, value, root_dir)
      C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\config\_apply_pyprojecttoml.py:55: SetuptoolsDeprecationWarning: 'tool.setuptools.license-files' is deprecated in favor of 'project.license-files' (available on setuptools>=77.0.0).
      !!

              ********************************************************************************

              By 2026-Feb-18, you need to update your project and remove deprecated calls
              or your builds will no longer be supported.

              See https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#license-files for details.
              ********************************************************************************

      !!
        _apply_tool_table(dist, config, filename)
      C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\config\_apply_pyprojecttoml.py:61: SetuptoolsDeprecationWarning: License classifiers are deprecated.
      !!

              ********************************************************************************
              Please consider removing the following classifiers in favor of a SPDX license expression:

              License :: OSI Approved :: Apache Software License

              See https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#license for details.
              ********************************************************************************

      !!
        dist._finalize_license_expression()
      C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\dist.py:759: SetuptoolsDeprecationWarning: License classifiers are deprecated.
      !!

              ********************************************************************************
              Please consider removing the following classifiers in favor of a SPDX license expression:

              License :: OSI Approved :: Apache Software License

              See https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#license for details.
              ********************************************************************************

      !!
        self._finalize_license_expression()
      running dist_info
      Traceback (most recent call last):
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\_normalization.py", line 62, in safe_version
          return str(packaging.version.Version(v))
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\packaging\version.py", line 202, in __init__
          raise InvalidVersion(f"Invalid version: {version!r}")
      packaging.version.InvalidVersion: Invalid version: '../../../../VERSION'

      During handling of the above exception, another exception occurred:

      Traceback (most recent call last):
        File "C:\Users\Joan\AppData\Local\pypoetry\Cache\virtualenvs\hough-STffMzkd-py3.12\Lib\site-packages\pip\_vendor\pyproject_hooks\_in_process\_in_process.py", line 353, in <module>
          main()
        File "C:\Users\Joan\AppData\Local\pypoetry\Cache\virtualenvs\hough-STffMzkd-py3.12\Lib\site-packages\pip\_vendor\pyproject_hooks\_in_process\_in_process.py", line 335, in main
          json_out['return_val'] = hook(**hook_input['kwargs'])
                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\Users\Joan\AppData\Local\pypoetry\Cache\virtualenvs\hough-STffMzkd-py3.12\Lib\site-packages\pip\_vendor\pyproject_hooks\_in_process\_in_process.py", line 181, in prepare_metadata_for_build_editable
          return hook(metadata_directory, config_settings)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\rapids_build_backend\impls.py", line 397, in prepare_metadata_for_build_editable
          return _get_backend(config.build_backend).prepare_metadata_for_build_editable(
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\build_meta.py", line 478, in prepare_metadata_for_build_editable
          return self.prepare_metadata_for_build_wheel(
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\build_meta.py", line 374, in prepare_metadata_for_build_wheel
          self.run_setup()
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\build_meta.py", line 317, in run_setup
          exec(code, locals())
        File "<string>", line 14, in <module>
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\__init__.py", line 117, in setup
          return distutils.core.setup(**attrs)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\_distutils\core.py", line 186, in setup
          return run_commands(dist)
                 ^^^^^^^^^^^^^^^^^^
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\_distutils\core.py", line 202, in run_commands
          dist.run_commands()
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\_distutils\dist.py", line 1002, in run_commands
          self.run_command(cmd)
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\dist.py", line 1104, in run_command
          super().run_command(command)
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\_distutils\dist.py", line 1020, in run_command
          cmd_obj.ensure_finalized()
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\_distutils\cmd.py", line 135, in ensure_finalized
          self.finalize_options()
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\command\dist_info.py", line 70, in finalize_options
          egg_info.finalize_options()
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\command\egg_info.py", line 225, in finalize_options
          self.egg_version = self.tagged_version()
                             ^^^^^^^^^^^^^^^^^^^^^
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\command\egg_info.py", line 131, in tagged_version
          return _normalization.safe_version(tagged)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\setuptools\_normalization.py", line 65, in safe_version
          return str(packaging.version.Version(attempt))
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "C:\TEMP\pip-build-env-ttrfehkz\overlay\Lib\site-packages\packaging\version.py", line 202, in __init__
          raise InvalidVersion(f"Invalid version: {version!r}")
      packaging.version.InvalidVersion: Invalid version: '..-..-..-..-VERSION'
      [end of output]

  note: This error originates from a subprocess, and is likely not a problem with pip.

[notice] A new release of pip is available: 24.3.1 -> 25.1
[notice] To update, run: python.exe -m pip install --upgrade pip
error: metadata-generation-failed

× Encountered error while generating package metadata.
╰─> See above for output.

note: This is an issue with the package mentioned above, not pip.
hint: See above for details.

[grlee77]

Thanks for reporting the issue @wohali,

Indeed, I was able to reproduce the above issue on a Windows environment. A workaround is to configure git to enable symbolic links on Windows. Creating the symbolic links also seems to require administrator priveleges.

I was using a Conda miniforge environment and what worked for me was:

1.) opened the terminal by right clicking on the usual "Miniforge Prompt" from the start menu to select "Run as Administrator".
2.) From within the terminal, I set a global setting for git to enable symbolic links:

git config --global --add core.symlinks true

3.) use the command as you provided above

pip install -e "git+https://github.com/rapidsai/cucim.git@v25.04.00#egg=cucim-cu12&subdirectory=python/cucim"

This is not an ideal solution either as not all Windows users may have administrator access. We can look at potential removing the several symlinks that are currently in the repository.

Another alternative solution to enabling symlinks is to clone the repository without symlink support and then copy the VERSION file from the root of the repository on top of the broken symbolic link version at python/cucim/VERSION and python/cucim/src/cucim/VERSION.

[wohali]

Cheers @grlee77 . Looks like git symlink support in Windows 10/11 is still very broken, especially when using .. in a path.

For now I've switched to using WSL2 for cucim, but for a native install I personally feel it would be best for the project to publish eggs that don't include symlinks.

[grlee77]

For now I've switched to using WSL2 for cucim, but for a native install I personally feel it would be best for the project to publish eggs that don't include symlinks.

A few months ago, we had discussed again a possible solution to providing pure Python windows wheels (without the C++-based I/O components) and conda packages, but have not had resources/time to dedicate to finish implementing that so far.

We can possibly look at a simpler change to remove symbolic links in the meantime.

[dpshepherd]

@grlee77 - I had time yesterday to test the proposed fix using admin privileges. I was able to get the install to work after copying where.exe to which.exe so that the builder could find nvcc. Thanks!!