diff --git a/pkgs/development/python-modules/et-xmlfile/default.nix b/pkgs/development/python-modules/et-xmlfile/default.nix
index b12bc700c5fb..4957e5c61fc8 100644
--- a/pkgs/development/python-modules/et-xmlfile/default.nix
+++ b/pkgs/development/python-modules/et-xmlfile/default.nix
@@ -2,6 +2,7 @@
   lib,
   buildPythonPackage,
   fetchFromGitLab,
+  fetchpatch,
   lxml,
   pytestCheckHook,
   pythonOlder,
@@ -23,6 +24,14 @@ buildPythonPackage rec {
     hash = "sha256-JZ1fJ9o4/Z+9uSlaoq+pNpLSwl5Yv6BJCI1G7GOaQ1I=";
   };
 
+  patches = [
+    (fetchpatch {
+      # python 3.14 compat
+      url = "https://foss.heptapod.net/openpyxl/et_xmlfile/-/commit/73172a7ce6d819ce13e6706f9a1c6d50f1646dde.patch";
+      hash = "sha256-PMtzIGtXJ/vp0VRmBodvyaG/Ptn2DwrTTC1EyLSChHU=";
+    })
+  ];
+
   build-system = [ setuptools ];
 
   nativeCheckInputs = [