The Cython work seems mature enough that we might want to make it more publicly accessible with an optional separate package. Is this easy to do? I don't think that we should make it default yet, but having it be easy to install by people who are not familiar with Cython or compilation would probably be a plus.

One option would be to have a separate conda package conda install -c conda-forge distributed-cython (I'm curious how this would play with the dask metapackage). I wonder also if there is some more blessed way to specify variants.

cc @jakirkham