[tox] envlist = py27, py35 [testenv] basepython = # we use TOXPYTHON env variable to specify the location of Appveyor Python py27: {env:TOXPYTHON:python2.7} py34: {env:TOXPYTHON:python3.4} py35: {env:TOXPYTHON:python3.5} deps = pytest -rrequirements.txt commands = # pass to pytest any extra positional arguments after `tox -- ...` pytest {posargs}