diff --git a/tox.ini b/tox.ini
index c03c47f3..a7593871 100644
--- a/tox.ini
+++ b/tox.ini
@@ -14,7 +14,7 @@ install_command = pip install {opts} {packages}
 commands =
   find . -type f -name "*.pyc" -delete
   python -V
-  py.test -vvv -s --ignore=hapi
+  py.test -vvv -s --ignore=hapi {posargs}
 
 [testenv:docs]
 commands =