diff --git a/authoritative-dns.nix b/authoritative-dns.nix
index 183b2ab..d3136a7 100644
--- a/authoritative-dns.nix
+++ b/authoritative-dns.nix
@@ -75,8 +75,7 @@ in {
       interfaces = cfg.listen-ips;
       stateDirectory = cfg.state-directory;
       zones = mapAttrs' (dom: domCfg:
-        let zoneCfg = domCfg.zone;
-        in nameValuePair "${dom}." {
+        nameValuePair "${dom}." {
           dnssec = zoneCfg.ksk.key-file != null;
           ksk.keyFile =
             mkIf (zoneCfg.ksk.key-file != null) zoneCfg.ksk.key-file;
diff --git a/nsd.nix b/nsd.nix
index a0dc327..772c569 100644
--- a/nsd.nix
+++ b/nsd.nix
@@ -315,9 +315,10 @@ let
 
       ksk = {
         keyFile = mkOption {
-          type = types.str;
+          type = nullOr types.str;
           description =
             "Location of the zone key-signing key file on the local host.";
+          default = null;
         };
       };
 
@@ -1058,8 +1059,5 @@ in {
         /run/current-system/systemd/bin/systemctl kill -s SIGHUP nsd.service
       '';
     };
-
   };
-
-  meta.maintainers = with lib.maintainers; [ hrdinka ];
 }