[tox] envlist = py36, py37, flake8 [travis] python = 3.7: py37 3.6: py36 [testenv:flake8] basepython = python deps = flake8 commands = flake8 flatland [testenv] setenv = PYTHONPATH = {toxinidir} deps = -r{toxinidir}/requirements_dev.txt ; If you want to make tox run the tests with the same versions, create a ; requirements.txt with the pinned versions and uncomment the following line: ; -r{toxinidir}/requirements.txt commands = pip install -U pip py.test --basetemp={envtmpdir}