The lxml project has decided to not provide a Wheel for lxml on Linux:
https://bugs.launchpad.net/lxml/+bug/1176147
I am neither an expert on PEP 427 or lxml's dependencies, so I'm hoping someone can explain why or why not the lxml team's concerns around providing a Wheel are valid?
lxml is 95+% of my build time, so I'm very interested in options to speed it up, and a Wheel seems like the official option.