diff --git a/pkgs/development/python-modules/mypy/default.nix b/pkgs/development/python-modules/mypy/default.nix
index 79a0cd86947f..01b502c88ed9 100644
--- a/pkgs/development/python-modules/mypy/default.nix
+++ b/pkgs/development/python-modules/mypy/default.nix
@@ -3,6 +3,7 @@
   stdenv,
   buildPythonPackage,
   fetchFromGitHub,
+  fetchpatch,
   gitUpdater,
   pythonAtLeast,
   pythonOlder,
@@ -46,6 +47,15 @@ buildPythonPackage rec {
     hash = "sha256-y67kt5i8mT9TcSbUGwnNuTAeqjy9apvWIbA2QD96LS4=";
   };
 
+  patches = [
+    # Fix the build on Darwin with a case‐sensitive store.
+    # Remove on next release.
+    (fetchpatch {
+      url = "https://github.com/python/mypy/commit/7534898319cb7f16738c11e4bc1bdcef0eb13c38.patch";
+      hash = "sha256-5jD0JBRnirmoMlUz9+n8G4AqHqCi8BaUX5rEl9NnLts=";
+    })
+  ];
+
   passthru.updateScript = gitUpdater {
     rev-prefix = "v";
   };