diff --git a/tox.ini b/tox.ini
index 7ff6e6a81..66204fa9d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -11,6 +11,16 @@ commands =
     coverage combine
     coverage report -m
 
+[testenv:diffcover]
+deps =
+    {[testenv]deps}
+    diff_cover
+commands =
+    python setup.py testr --coverage
+    coverage combine
+    coverage xml
+    diff-cover --fail-under 100 coverage.xml
+
 [testenv:cover]
 commands = coverage html {posargs:--include="*barbican*"}