I don't know how you'd install Twisted without setuptools these days anyway, but just as a heads up, as per discussion on <https://twistedmatrix.com/trac/ticket/3696#comment:79> we are going to remove any pretense of supporting Twisted without setuptools installed.

I am probably going to install it on the last buildbot environment that doesn't have it tomorrow.  If you have a strong case for continuing to support optionally depending on setuptools... well, I am probably still going to do that and we can file some more tickets to support it properly instead of by accident later :).

-glyph