diff --git a/pkgs/data/themes/qtcurve/default.nix b/pkgs/data/themes/qtcurve/default.nix
index 9339cdbf3380..2265c3550aed 100644
--- a/pkgs/data/themes/qtcurve/default.nix
+++ b/pkgs/data/themes/qtcurve/default.nix
@@ -39,6 +39,11 @@ mkDerivation rec {
   };
 
   patches = [
+    # Fix build with CMake 4
+    (fetchpatch {
+      url = "https://github.com/KDE/qtcurve/commit/d2c84577505641e647fbb64bce825b3e0a4129f5.patch";
+      sha256 = "sha256-WBmzlVDxRNXZmi6c03cR1MuIr+hBaeFXgNLzhsv0bZo=";
+    })
     # Remove unnecessary constexpr, this is not allowed in C++14
     (fetchpatch {
       url = "https://github.com/KDE/qtcurve/commit/ee2228ea2f18ac5da9b434ee6089381df815aa94.patch";