VTK now contains wheel-building logic in its own master branch now (9.0 will have it too). This is done so that you can build any VTK you want with whichever modules you want. I need to write docs for how to use it, but I sketched the outlines of what is necessary in this post: https://discourse.vtk.org/t/vtkxdmf3writer-not-in-python-pypi-distribution/2470/2.