diff --git a/requirements.txt b/requirements.txt
index 46337389c..524edf69d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -28,3 +28,4 @@ pytest-timeout>=1.3.0,<2.0.0
 mock>=2.0.0,<3.0.0
 flake8>=3.5.0,<3.6.0
 hypothesis>=3.27.0,<7.0.0
+mypy==0.910