diff --git a/tox.ini b/tox.ini
index 00c8d19e..52fbdff7 100644
--- a/tox.ini
+++ b/tox.ini
@@ -5,6 +5,9 @@ envlist = pep8,py35,bandit,docs
 basepython=python3
 passenv = http_proxy HTTP_PROXY https_proxy HTTPS_PROXY no_proxy NO_PROXY
 
+[testenv:venv]
+commands = {posargs}
+
 [testenv:py35]
 setenv =
   PYTHONWARNING=all