diff --git a/tox.ini b/tox.ini
index b2a693b..40529e8 100644
--- a/tox.ini
+++ b/tox.ini
@@ -14,6 +14,7 @@ python =
 [testenv]
 deps =
     freezegun
+    itsdangerous <= 2.0.1
     pandas
     prefect
     pytest