diff --git a/pkgs/by-name/co/cosmic-settings/package.nix b/pkgs/by-name/co/cosmic-settings/package.nix
index 6b87890037e3..181a5eb64eb8 100644
--- a/pkgs/by-name/co/cosmic-settings/package.nix
+++ b/pkgs/by-name/co/cosmic-settings/package.nix
@@ -11,6 +11,7 @@
   libinput,
   fontconfig,
   freetype,
+  isocodes,
   pipewire,
   pulseaudio,
   udev,
@@ -73,6 +74,7 @@ rustPlatform.buildRustPackage (finalAttrs: {
   preFixup = ''
     libcosmicAppWrapperArgs+=(
       --prefix PATH : ${lib.makeBinPath [ cosmic-randr ]}
+      --prefix XDG_DATA_DIRS : ${lib.makeSearchPathOutput "bin" "share" [ isocodes ]}
       --set-default X11_BASE_RULES_XML ${xkeyboard_config}/share/X11/xkb/rules/base.xml
       --set-default X11_BASE_EXTRA_RULES_XML ${xkeyboard_config}/share/X11/xkb/rules/extra.xml
     )