diff --git a/pkgs/tools/typesetting/psutils/default.nix b/pkgs/tools/typesetting/psutils/default.nix
index f0f44881a1e..3ff93ad2301 100644
--- a/pkgs/tools/typesetting/psutils/default.nix
+++ b/pkgs/tools/typesetting/psutils/default.nix
@@ -25,5 +25,6 @@ stdenv.mkDerivation rec {
     description = "Collection of useful utilities for manipulating PS documents";
     homepage = "http://knackered.knackered.org/angus/psutils/";
     license = lib.licenses.bsd3;
+    platforms = lib.platforms.unix;
   };
 }