diff --git a/pkgs/development/python-modules/subunit/default.nix b/pkgs/development/python-modules/subunit/default.nix
index 9587d0df0fff..83bfd25c6b64 100644
--- a/pkgs/development/python-modules/subunit/default.nix
+++ b/pkgs/development/python-modules/subunit/default.nix
@@ -4,6 +4,7 @@
 , cppunit
 , pkg-config
 , subunit
+, pythonOlder
 
 # python dependencies
 , fixtures