diff --git a/pkgs/tools/networking/hblock/default.nix b/pkgs/tools/networking/hblock/default.nix
index b3a2b9d68225..8d7f25678edf 100644
--- a/pkgs/tools/networking/hblock/default.nix
+++ b/pkgs/tools/networking/hblock/default.nix
@@ -35,5 +35,6 @@ stdenv.mkDerivation rec {
     homepage = "https://github.com/hectorm/hblock";
     license = licenses.mit;
     maintainers = with maintainers; [ alanpearce ];
+    platforms = platforms.unix;
   };
 }