split xarray into multi-output

[kmuehlbauer]

Comment:

See pydata/xarray#9149

Examples of multi-output feedstocks

• gdal https://github.com/conda-forge/gdal-feedstock/blob/main/recipe/meta.yaml
• matplotlib https://github.com/conda-forge/matplotlib-feedstock/blob/main/recipe/meta.yaml
• typing https://github.com/conda-forge/typing_extensions-feedstock/blob/main/recipe/meta.yaml
• jupyter-sphinx https://github.com/conda-forge/jupyter-sphinx-feedstock/blob/main/recipe/meta.yaml

two feedstock example

• dask-core https://github.com/conda-forge/dask-feedstock/blob/main/recipe/meta.yaml
• dask https://github.com/conda-forge/dask-core-feedstock/blob/main/recipe/meta.yaml

I'll try to get a pull request online soon.

[kmuehlbauer]

First draft in #113.

[weiji14]

FYI, there is a conda enhancement proposal for optional dependencies in conda-forge (see conda/conda#7502, https://prefix.dev/blog/ceps_2025#optional-dependencies,-conditional-dependencies,-and-flags) that should land anytime now. Maybe best to wait for that instead of going ahead with the package split.

[keewis]

if I understand that proposal correctly, it would basically give us the same features as those we have on PyPI. This would make it so much easier to synchronize PyPI and conda-forge, which is currently the main blocker for #113.

However, the other missing piece is PEP771 (https://discuss.python.org/t/pep-771-default-extras-for-python-software-packages-round-2/94905), which would allow default extras, which would allow us to specify a set of packages that would make xarray as useful as possible by default.

We had considered to publish a xarray-core package to PyPI and conda-forge, which would always remain a minimal install, which would allow us to modify the dependencies of the main xarray package.

[AntoinePrv]

When the CEP is accepted, it is not immediately available in all installers (especially conda/mamba, pixi being faster since this is where the POC is coming from).
And it takes even more time for users to update their local installer to a more recent version.