diff --git a/tox.ini b/tox.ini
index 5a04768..bb3d15e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -46,6 +46,7 @@ commands =
       --cov-report=html:{envdir}/htmlcov --cov-context=test \
       --cov-report=xml:{toxworkdir}/coverage.{envname}.xml \
       tests
+    ;   {posargs:-n auto} tests
 
 
 [testenv:dev]