PEP 517 and projects that can't install via wheels

[pf_moore (Paul Moore)]

@dstufft

I think the future is that we always install via wheel

Agreed, but we have to publicise that better, as it’s a backward incompatible change and I’m getting tired of dealing with (legitimate) complaints that we broke people’s packages without warning

@takluyver

If there are some that still can’t build a wheel, pip might need some kind of legacy install mode to handle them.

We have that legacy mode at the moment - setup.py installs are (at least in my mind ) legacy since PEP 517 support was released. The problem is that we can’t support that (or any other) legacy mode indefinitely, so the question is when (and how) we remove it.