Such a minimal windows test environment should have no C/C++ compiler installed, nor SDK, nor redistributable runtime such as c:\Windows\System32\vcomp140.dll nor even Miniconda. Indeed Miniconda ships its own bunch of system dlls such as vcomp140.dll by default.

The goal would be to detect problems such as scikit-learn/scikit-learn#15899 before releasing.

Instead it should install Python from https://www.python.org (e.g. an embedded zip or from the .msi installer which can be installed from the command line).

We should probably do that based on #23 as the current AppVeyor worker is really too slow to iterate with.

A minimal test environment is probably achievable using a Windows servercore container although I have never tried myself.

References

Powershell script to download install python .msi from python.org:
https://github.com/ogrisel/python-appveyor-demo/blob/master/appveyor/install.ps1#L104

Windows containers on Azure Pipelines:
https://docs.microsoft.com/en-us/azure/devops/pipelines/process/container-phases?view=azure-devops&tabs=yaml#windows-containers