diff --git a/tox.ini b/tox.ini
index be0f076..6d4496d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -7,6 +7,9 @@ basepython=python3
 deps=
   -rdoc/requirements.txt
 
+[testenv:venv]
+commands = {posargs}
+
 [testenv:docs]
 whitelist_externals=
   rm