nixos/rippled: define group, fix eval after #133166

nixos/modules/misc/ids.nix

@@ -153,7 +153,7 @@ in
       #btsync = 113; # unused
       #minecraft = 114; #dynamically allocated as of 2021-09-03
       vault = 115;
-      rippled = 116;
+      # rippled = 116; #dynamically allocated as of 2021-09-18
       murmur = 117;
       foundationdb = 118;
       newrelic = 119;

nixos/modules/services/misc/rippled.nix

@@ -407,12 +407,14 @@ in
 
   config = mkIf cfg.enable {
 
-    users.users.rippled =
-      { description = "Ripple server user";
-        uid = config.ids.uids.rippled;
+    users.users.rippled = {
+        description = "Ripple server user";
+        isSystemUser = true;
+        group = "rippled";
         home = cfg.databasePath;
         createHome = true;
       };
+    users.groups.rippled = {};
 
     systemd.services.rippled = {
       after = [ "network.target" ];