diff --git a/pkgs/development/python-modules/nocasedict/default.nix b/pkgs/development/python-modules/nocasedict/default.nix
index 7dc6d610832a..c9267ca3f646 100644
--- a/pkgs/development/python-modules/nocasedict/default.nix
+++ b/pkgs/development/python-modules/nocasedict/default.nix
@@ -5,6 +5,7 @@
   pytestCheckHook,
   setuptools,
   setuptools-scm,
+  typing-extensions,
 }:
 
 buildPythonPackage (finalAttrs: {
@@ -24,6 +25,8 @@ buildPythonPackage (finalAttrs: {
     setuptools-scm
   ];
 
+  dependencies = [ typing-extensions ];
+
   nativeCheckInputs = [ pytestCheckHook ];
 
   pythonImportsCheck = [ "nocasedict" ];