$ pixi lock
  ⠤ default:osx-64       [00:00:04] resolving scipy==1.17.1
  ⠤ default:osx-arm64    [00:00:04] resolving scipy==1.17.1
  ⠴ default:linux-64     [00:00:03] resolving scipy==1.17.1                                                                                Error:   x failed to solve the pypi requirements of environment 'py39' for platform 'osx-64'
  |-> failed to resolve pypi dependencies
  `-> Because the requested Python version (==3.9.*) does not satisfy Python>=3.10 and scipy>=1.14.1,<=1.15.3 depends on Python>=3.10, we
      can conclude that scipy>=1.14.1,<=1.15.3 cannot be used.
      And because only the following versions of scipy are available:
          scipy<=1.14.1
          scipy==1.15.0
          scipy==1.15.1
          scipy==1.15.2
          scipy==1.15.3
          scipy==1.16.0
          scipy==1.16.1
          scipy==1.16.2
          scipy==1.16.3
          scipy==1.17.0
          scipy==1.17.1
      we can conclude that scipy>=1.14.1,<1.16.0 cannot be used. (1)
      
      Because the requested Python version (==3.9.*) does not satisfy Python>=3.11 and scipy>=1.16.0 depends on Python>=3.11, we can
      conclude that scipy>=1.16.0 cannot be used.
      And because we know from (1) that scipy>=1.14.1,<1.16.0 cannot be used, we can conclude that scipy>=1.14.1 cannot be used.
      And because you require scipy>=1.14.1, we can conclude that your requirements are unsatisfiable.
      
      hint: Pre-releases are available for `scipy` in the requested range (e.g., 1.17.0rc2), but pre-releases weren't enabled (try:
      `--prerelease=allow`)
      
      hint: The `requires-python` value (==3.9.*) includes Python versions that are not supported by your dependencies (e.g.,
      scipy>=1.14.1,<=1.15.3 only supports >=3.10). Consider using a more restrictive `requires-python` value (like >=3.10).