does 6aa00da only affect travis?

6aa00da will apply if you run your tests locally using tox as well.

so that fix is now out, but we can't use it because the http is broken instead?

not sure i understand the reason for the tox change

Yes :(

I've had some discussion about the breaking change in eventlet/eventlet#420 but honestly got a bit lost with it.

The tox change is required because we were no longer actually testing against eventlet master. See https://travis-ci.org/nameko/nameko/builds/328005814?utm_source=github_status&utm_medium=notification

Before the change tox was executing the following commands:

pip install --upgrade https://github.com/eventlet/eventlet/archive/master.zip (from mastereventlet match)
pip install --editable .[dev] (from lib match)
make test_lib (from lib match)

pip install --editable .[dev] after pip install ...master.zip was pulling eventlet back down to the pinned version