diff --git a/nix/srcds/default.nix b/nix/srcds/default.nix
index 42a5b99..be1dda5 100644
--- a/nix/srcds/default.nix
+++ b/nix/srcds/default.nix
@@ -80,6 +80,8 @@ in
       cp ${steamworks-sdk-redist}/lib/steamclient.so $out/bin/steamclient.so
       chmod -R +w $out/bin/steamclient.so
 
+      echo 440 > $out/steam_appid.txt
+
       runHook postInstall
     '';