diff --git a/tox.ini b/tox.ini
index 84245697..1f5445bd 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,6 +9,7 @@ setenv =
 commands =
     python build.py --modules
     flake8
+    black --check .
     {posargs:py.test core hscommon}
 deps =
     -r{toxinidir}/requirements.txt