diff --git a/tox.ini b/tox.ini
index e03525b..379bb38 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,7 +9,7 @@ setenv=
   DJANGO_SETTINGS_MODULE=settings
   PYTHONPATH=src:tests
 commands =
-  py.test --cov=src/ tests
+  py.test --cov=src/ tests {posargs}
 usedevelop = True
 deps = coverage
   pytest