I have a tox.ini like this
[tox] skipsdist = True envlist = begin,py35,py36,end [testenv] commands = pip install -e git+ssh://git@bitbucket.org/org/repo#egg
My guess was to try quoting the URL:
[testenv] commands = pip install -e "git+ssh://git@bitbucket.org/org/repo#egg=repo[server]"
and that seems to do the trick.