Conda builds for Windows
First we should try and get a build without mumps working, then try to get mumps working.
Given that currently the entire Kwant recipe depends on openblas, this issue does not fill me with confidence that the Windows build will be easy, or indeed possible at all at this point. There appears to be a lot of yack shaving on that issue discussion.
It appears that even numpy and scipy do not even have windows builds on conda forge (probably due to the aforementioned issue with openblas).