diff --git a/pkgs/by-name/ks/kstars/package.nix b/pkgs/by-name/ks/kstars/package.nix
index 70eb1b865a68..589c0ee5aa4e 100644
--- a/pkgs/by-name/ks/kstars/package.nix
+++ b/pkgs/by-name/ks/kstars/package.nix
@@ -73,7 +73,7 @@ stdenv.mkDerivation (finalAttrs: {
     (cmakeBool "BUILD_QT5" false)
     (cmakeFeature "INDI_PREFIX" "${indi-full}")
     (cmakeFeature "XPLANET_PREFIX" "${xplanet}")
-    (cmakeFeature "DATA_INSTALL_DIR" "$out/share/kstars/")
+    (cmakeFeature "DATA_INSTALL_DIR" (placeholder "out") + "/share/kstars/")
   ];
 
   meta = with lib; {