diff --git a/pkgs/development/python-modules/mitmproxy/default.nix b/pkgs/development/python-modules/mitmproxy/default.nix
index 62fe35f10390..4dd3baeb614c 100644
--- a/pkgs/development/python-modules/mitmproxy/default.nix
+++ b/pkgs/development/python-modules/mitmproxy/default.nix
@@ -63,6 +63,7 @@ buildPythonPackage rec {
 
   pythonRelaxDeps = [
     "aioquic"
+    "cryptography"
   ];
 
   propagatedBuildInputs = [