Mayavi does not support PEP517

[Sbozzolo]

After something updated (I don't know exactly what), mayavi has started breaking the continuous integration for my package.

I tracked this down and I think that the reason is that mayavi does not support PEP517. Poetry tries to install mayavi with --use-pep517, and the installation fails because the build is done in isolated environment that does not have numpy.

What is the correct way to approach this problem?

[Sbozzolo]

Dupe of https://github.com/enthought/mayavi/issues/1075

It looks like that this makes mayavi impossible to use in downstream projects that utilize poetry