Merge pull request #133166 from symphorien/nonogroup

Don't default to nogroup for the primary group of users.

46 files changed, 151 insertions, 52 deletions

diff --git a/nixos/modules/config/users-groups.nix b/nixos/modules/config/users-groups.nix
index d88162558e6..8e2db9107a1 100644
--- a/nixos/modules/config/users-groups.nix
+++ b/nixos/modules/config/users-groups.nix
@@ -123,7 +123,7 @@ let
       group = mkOption {
         type = types.str;
         apply = x: assert (builtins.stringLength x < 32 || abort "Group name '${x}' is longer than 31 characters which is not allowed!"); x;
-        default = "nogroup";
+        default = "";
         description = "The user's primary group.";
       };
 
@@ -640,6 +640,16 @@ in {
               Exactly one of users.users.${user.name}.isSystemUser and users.users.${user.name}.isNormalUser must be set.
             '';
           }
+          {
+            assertion = user.group != "";
+            message = ''
+              users.users.${user.name}.group is unset. This used to default to
+              nogroup, but this is unsafe. For example you can create a group
+              for this user with:
+              users.users.${user.name}.group = "${user.name}";
+              users.groups.${user.name} = {};
+            '';
+          }
         ]
     ));
 
diff --git a/nixos/modules/misc/ids.nix b/nixos/modules/misc/ids.nix
index 02ae1390ce8..30cd8615acf 100644
--- a/nixos/modules/misc/ids.nix
+++ b/nixos/modules/misc/ids.nix
@@ -83,14 +83,14 @@ in
       #fourstore = 42; # dropped in 20.03
       #fourstorehttp = 43; # dropped in 20.03
       virtuoso = 44;
-      rtkit = 45;
+      #rtkit = 45; # dynamically allocated 2021-09-03
       dovecot2 = 46;
       dovenull2 = 47;
       prayer = 49;
       mpd = 50;
       clamav = 51;
       fprot = 52;
-      bind = 53;
+      # bind = 53; #dynamically allocated as of 2021-09-03
       wwwrun = 54;
       #adm = 55; # unused
       spamd = 56;
@@ -134,13 +134,13 @@ in
       firebird = 95;
       #keys = 96; # unused
       #haproxy = 97; # dynamically allocated as of 2020-03-11
-      mongodb = 98;
+      #mongodb = 98; #dynamically allocated as of 2021-09-03
       #openldap = 99; # dynamically allocated as of PR#94610
       #users = 100; # unused
       cgminer = 101;
       munin = 102;
       logcheck = 103;
-      nix-ssh = 104;
+      #nix-ssh = 104; #dynamically allocated as of 2021-09-03
       dictd = 105;
       couchdb = 106;
       #searx = 107; # dynamically allocated as of 2020-10-27
@@ -149,9 +149,9 @@ in
       systemd-journal-gateway = 110;
       #notbit = 111; # unused
       aerospike = 111;
-      ngircd = 112;
+      #ngircd = 112; #dynamically allocated as of 2021-09-03
       #btsync = 113; # unused
-      minecraft = 114;
+      #minecraft = 114; #dynamically allocated as of 2021-09-03
       vault = 115;
       rippled = 116;
       murmur = 117;
@@ -169,19 +169,19 @@ in
       mopidy = 130;
       #docker = 131; # unused
       gdm = 132;
-      dhcpd = 133;
+      #dhcpd = 133; # dynamically allocated as of 2021-09-03
       siproxd = 134;
       mlmmj = 135;
-      neo4j = 136;
+      #neo4j = 136;# dynamically allocated as of 2021-09-03
       riemann = 137;
       riemanndash = 138;
-      radvd = 139;
-      zookeeper = 140;
-      dnsmasq = 141;
+      #radvd = 139;# dynamically allocated as of 2021-09-03
+      #zookeeper = 140;# dynamically allocated as of 2021-09-03
+      #dnsmasq = 141;# dynamically allocated as of 2021-09-03
       #uhub = 142; # unused
       yandexdisk = 143;
       mxisd = 144; # was once collectd
-      consul = 145;
+      #consul = 145;# dynamically allocated as of 2021-09-03
       mailpile = 146;
       redmine = 147;
       #seeks = 148; # removed 2020-06-21
@@ -192,7 +192,7 @@ in
       systemd-resolve = 153;
       systemd-timesync = 154;
       liquidsoap = 155;
-      etcd = 156;
+      #etcd = 156;# dynamically allocated as of 2021-09-03
       hbase = 158;
       opentsdb = 159;
       scollector = 160;
@@ -204,7 +204,7 @@ in
       tox-bootstrapd = 166;
       cadvisor = 167;
       nylon = 168;
-      apache-kafka = 169;
+      #apache-kafka = 169;# dynamically allocated as of 2021-09-03
       #panamax = 170; # unused
       exim = 172;
       #fleet = 173; # unused
@@ -241,7 +241,7 @@ in
       gateone = 207;
       namecoin = 208;
       #lxd = 210; # unused
-      kibana = 211;
+      #kibana = 211;# dynamically allocated as of 2021-09-03
       xtreemfs = 212;
       calibre-server = 213;
       heapster = 214;
@@ -264,7 +264,7 @@ in
       avahi-autoipd = 231;
       nntp-proxy = 232;
       mjpg-streamer = 233;
-      radicale = 234;
+      #radicale = 234;# dynamically allocated as of 2021-09-03
       hydra-queue-runner = 235;
       hydra-www = 236;
       syncthing = 237;
@@ -272,14 +272,14 @@ in
       taskd = 240;
       # factorio = 241; # DynamicUser = true
       # emby = 242; # unusued, removed 2019-05-01
-      graylog = 243;
+      #graylog = 243;# dynamically allocated as of 2021-09-03
       sniproxy = 244;
       nzbget = 245;
       mosquitto = 246;
       toxvpn = 247;
       # squeezelite = 248; # DynamicUser = true
       turnserver = 249;
-      smokeping = 250;
+      #smokeping = 250;# dynamically allocated as of 2021-09-03
       gocd-agent = 251;
       gocd-server = 252;
       terraria = 253;
@@ -554,7 +554,7 @@ in
       #shout = 206; #unused
       gateone = 207;
       namecoin = 208;
-      lxd = 210; # unused
+      #lxd = 210; # unused
       #kibana = 211;
       xtreemfs = 212;
       calibre-server = 213;
@@ -573,7 +573,7 @@ in
       cfdyndns = 227;
       pdnsd = 229;
       octoprint = 230;
-      radicale = 234;
+      #radicale = 234;# dynamically allocated as of 2021-09-03
       syncthing = 237;
       caddy = 239;
       taskd = 240;
@@ -585,7 +585,7 @@ in
       #toxvpn = 247; # unused
       #squeezelite = 248; #unused
       turnserver = 249;
-      smokeping = 250;
+      #smokeping = 250;# dynamically allocated as of 2021-09-03
       gocd-agent = 251;
       gocd-server = 252;
       terraria = 253;
diff --git a/nixos/modules/security/rtkit.nix b/nixos/modules/security/rtkit.nix
index a7b27cbcf21..ad8746808e8 100644
--- a/nixos/modules/security/rtkit.nix
+++ b/nixos/modules/security/rtkit.nix
@@ -35,9 +35,12 @@ with lib;
     services.dbus.packages = [ pkgs.rtkit ];
 
     users.users.rtkit =
-      { uid = config.ids.uids.rtkit;
+      {
+        isSystemUser = true;
+        group = "rtkit";
         description = "RealtimeKit daemon";
       };
+    users.groups.rtkit = {};
 
   };
 
diff --git a/nixos/modules/services/backup/borgbackup.nix b/nixos/modules/services/backup/borgbackup.nix
index ccbc7726392..c4174286fc0 100644
--- a/nixos/modules/services/backup/borgbackup.nix
+++ b/nixos/modules/services/backup/borgbackup.nix
@@ -169,6 +169,7 @@ let
         (map (mkAuthorizedKey cfg false) cfg.authorizedKeys
         ++ map (mkAuthorizedKey cfg true) cfg.authorizedKeysAppendOnly);
       useDefaultShell = true;
+      group = cfg.group;
       isSystemUser = true;
     };
     groups.${cfg.group} = { };
diff --git a/nixos/modules/services/databases/influxdb.nix b/nixos/modules/services/databases/influxdb.nix
index dd5d69b1147..3b8c00929ba 100644
--- a/nixos/modules/services/databases/influxdb.nix
+++ b/nixos/modules/services/databases/influxdb.nix
@@ -185,6 +185,7 @@ in
     users.users = optionalAttrs (cfg.user == "influxdb") {
       influxdb = {
         uid = config.ids.uids.influxdb;
+        group = "influxdb";
         description = "Influxdb daemon user";
       };
     };
diff --git a/nixos/modules/services/databases/memcached.nix b/nixos/modules/services/databases/memcached.nix
index ca7b20eb049..1c06937e2f3 100644
--- a/nixos/modules/services/databases/memcached.nix
+++ b/nixos/modules/services/databases/memcached.nix
@@ -67,7 +67,9 @@ in
     users.users = optionalAttrs (cfg.user == "memcached") {
       memcached.description = "Memcached server user";
       memcached.isSystemUser = true;
+      memcached.group = "memcached";
     };
+    users.groups = optionalAttrs (cfg.user == "memcached") { memcached = {}; };
 
     environment.systemPackages = [ memcached ];
 
diff --git a/nixos/modules/services/databases/mongodb.nix b/nixos/modules/services/databases/mongodb.nix
index db1e5fedf50..5121e0415db 100644
--- a/nixos/modules/services/databases/mongodb.nix
+++ b/nixos/modules/services/databases/mongodb.nix
@@ -123,9 +123,11 @@ in
 
     users.users.mongodb = mkIf (cfg.user == "mongodb")
       { name = "mongodb";
-        uid = config.ids.uids.mongodb;
+        isSystemUser = true;
+        group = "mongodb";
         description = "MongoDB server user";
       };
+    users.groups.mongodb = mkIf (cfg.user == "mongodb") {};
 
     environment.systemPackages = [ mongodb ];
 
diff --git a/nixos/modules/services/databases/neo4j.nix b/nixos/modules/services/databases/neo4j.nix
index 53760bb24c4..2a30923538d 100644
--- a/nixos/modules/services/databases/neo4j.nix
+++ b/nixos/modules/services/databases/neo4j.nix
@@ -651,10 +651,12 @@ in {
       environment.systemPackages = [ cfg.package ];
 
       users.users.neo4j = {
-        uid = config.ids.uids.neo4j;
+        isSystemUser = true;
+        group = "neo4j";
         description = "Neo4j daemon user";
         home = cfg.directories.home;
       };
+      users.groups.neo4j = {};
     };
 
   meta = {
diff --git a/nixos/modules/services/databases/redis.nix b/nixos/modules/services/databases/redis.nix
index 8873f6d00e0..1b9358c81a1 100644
--- a/nixos/modules/services/databases/redis.nix
+++ b/nixos/modules/services/databases/redis.nix
@@ -246,6 +246,7 @@ in {
 
     users.users.redis = {
       description = "Redis database user";
+      group = "redis";
       isSystemUser = true;
     };
     users.groups.redis = {};
diff --git a/nixos/modules/services/games/minecraft-server.nix b/nixos/modules/services/games/minecraft-server.nix
index eb9288fca58..458e57fef84 100644
--- a/nixos/modules/services/games/minecraft-server.nix
+++ b/nixos/modules/services/games/minecraft-server.nix
@@ -167,8 +167,10 @@ in {
       description     = "Minecraft server service user";
       home            = cfg.dataDir;
       createHome      = true;
-      uid             = config.ids.uids.minecraft;
+      isSystemUser    = true;
+      group           = "minecraft";
     };
+    users.groups.minecraft = {};
 
     systemd.services.minecraft-server = {
       description   = "Minecraft Server Service";
diff --git a/nixos/modules/services/logging/graylog.nix b/nixos/modules/services/logging/graylog.nix
index af70d27fcf9..5e20a10f249 100644
--- a/nixos/modules/services/logging/graylog.nix
+++ b/nixos/modules/services/logging/graylog.nix
@@ -128,10 +128,12 @@ in
 
     users.users = mkIf (cfg.user == "graylog") {
       graylog = {
-        uid = config.ids.uids.graylog;
+        isSystemUser = true;
+        group = "graylog";
         description = "Graylog server daemon user";
       };
     };
+    users.groups = mkIf (cfg.user == "graylog") {};
 
     systemd.tmpfiles.rules = [
       "d '${cfg.messageJournalDir}' - ${cfg.user} - - -"
diff --git a/nixos/modules/services/misc/airsonic.nix b/nixos/modules/services/misc/airsonic.nix
index 490f6c5a5c0..c1ce515750b 100644
--- a/nixos/modules/services/misc/airsonic.nix
+++ b/nixos/modules/services/misc/airsonic.nix
@@ -165,10 +165,12 @@ in {
 
     users.users.airsonic = {
       description = "Airsonic service user";
+      group = "airsonic";
       name = cfg.user;
       home = cfg.home;
       createHome = true;
       isSystemUser = true;
     };
+    users.groups.airsonic = {};
   };
 }
diff --git a/nixos/modules/services/misc/apache-kafka.nix b/nixos/modules/services/misc/apache-kafka.nix
index 69dfadfe54e..8bc307311a4 100644
--- a/nixos/modules/services/misc/apache-kafka.nix
+++ b/nixos/modules/services/misc/apache-kafka.nix
@@ -120,10 +120,12 @@ in {
     environment.systemPackages = [cfg.package];
 
     users.users.apache-kafka = {
-      uid = config.ids.uids.apache-kafka;
+      isSystemUser = true;
+      group = "apache-kafka";
       description = "Apache Kafka daemon user";
       home = head cfg.logDirs;
     };
+    users.groups.apache-kafka = {};
 
     systemd.tmpfiles.rules = map (logDir: "d '${logDir}' 0700 apache-kafka - - -") cfg.logDirs;
 
diff --git a/nixos/modules/services/misc/docker-registry.nix b/nixos/modules/services/misc/docker-registry.nix
index e212f581c28..cb68a29c530 100644
--- a/nixos/modules/services/misc/docker-registry.nix
+++ b/nixos/modules/services/misc/docker-registry.nix
@@ -151,7 +151,9 @@ in {
         home = cfg.storagePath;
       }
       else {}) // {
+        group = "docker-registry";
         isSystemUser = true;
       };
+    users.groups.docker-registry = {};
   };
 }
diff --git a/nixos/modules/services/misc/etcd.nix b/nixos/modules/services/misc/etcd.nix
index eb266f043eb..2b667fab6b0 100644
--- a/nixos/modules/services/misc/etcd.nix
+++ b/nixos/modules/services/misc/etcd.nix
@@ -187,9 +187,11 @@ in {
     environment.systemPackages = [ pkgs.etcd ];
 
     users.users.etcd = {
-      uid = config.ids.uids.etcd;
+      isSystemUser = true;
+      group = "etcd";
       description = "Etcd daemon user";
       home = cfg.dataDir;
     };
+    users.groups.etcd = {};
   };
 }
diff --git a/nixos/modules/services/misc/nix-ssh-serve.nix b/nixos/modules/services/misc/nix-ssh-serve.nix
index 1764c6d7964..d5c64fdb264 100644
--- a/nixos/modules/services/misc/nix-ssh-serve.nix
+++ b/nixos/modules/services/misc/nix-ssh-serve.nix
@@ -44,9 +44,11 @@ in {
 
     users.users.nix-ssh = {
       description = "Nix SSH store user";
-      uid = config.ids.uids.nix-ssh;
+      isSystemUser = true;
+      group = "nix-ssh";
       useDefaultShell = true;
     };
+    users.groups.nix-ssh = {};
 
     services.openssh.enable = true;
 
diff --git a/nixos/modules/services/misc/zookeeper.nix b/nixos/modules/services/misc/zookeeper.nix
index 1d12e81a9ec..0e5880983e4 100644
--- a/nixos/modules/services/misc/zookeeper.nix
+++ b/nixos/modules/services/misc/zookeeper.nix
@@ -148,9 +148,11 @@ in {
     };
 
     users.users.zookeeper = {
-      uid = config.ids.uids.zookeeper;
+      isSystemUser = true;
+      group = "zookeeper";
       description = "Zookeeper daemon user";
       home = cfg.dataDir;
     };
+    users.groups.zookeeper = {};
   };
 }
diff --git a/nixos/modules/services/monitoring/graphite.nix b/nixos/modules/services/monitoring/graphite.nix
index 9213748d3c9..502afce5233 100644
--- a/nixos/modules/services/monitoring/graphite.nix
+++ b/nixos/modules/services/monitoring/graphite.nix
@@ -561,6 +561,7 @@ in {
      ) {
       users.users.graphite = {
         uid = config.ids.uids.graphite;
+        group = "graphite";
         description = "Graphite daemon user";
         home = dataDir;
       };
diff --git a/nixos/modules/services/monitoring/netdata.nix b/nixos/modules/services/monitoring/netdata.nix
index 561ce3eec62..e76979fa6d1 100644
--- a/nixos/modules/services/monitoring/netdata.nix
+++ b/nixos/modules/services/monitoring/netdata.nix
@@ -258,6 +258,7 @@ in {
 
     users.users = optionalAttrs (cfg.user == defaultUser) {
       ${defaultUser} = {
+        group = defaultUser;
         isSystemUser = true;
       };
     };
diff --git a/nixos/modules/services/monitoring/tuptime.nix b/nixos/modules/services/monitoring/tuptime.nix
index 17c5c1f56ea..de80282559a 100644
--- a/nixos/modules/services/monitoring/tuptime.nix
+++ b/nixos/modules/services/monitoring/tuptime.nix
@@ -36,6 +36,7 @@ in {
       groups._tuptime.members = [ "_tuptime" ];
       users._tuptime = {
         isSystemUser = true;
+        group = "_tuptime";
         description = "tuptime database owner";
       };
     };
diff --git a/nixos/modules/services/network-filesystems/orangefs/server.nix b/nixos/modules/services/network-filesystems/orangefs/server.nix
index 8eb754fe611..8c55ccf5ffb 100644
--- a/nixos/modules/services/network-filesystems/orangefs/server.nix
+++ b/nixos/modules/services/network-filesystems/orangefs/server.nix
@@ -193,7 +193,10 @@ in {
     environment.systemPackages = [ pkgs.orangefs ];
 
     # orangefs daemon will run as user
-    users.users.orangefs.isSystemUser = true;
+    users.users.orangefs = {
+      isSystemUser = true;
+      group = "orangfs";
+    };
     users.groups.orangefs = {};
 
     # To format the file system the config file is needed.
diff --git a/nixos/modules/services/networking/bind.nix b/nixos/modules/services/networking/bind.nix
index 480d5a184f2..0c23fb7e40f 100644
--- a/nixos/modules/services/networking/bind.nix
+++ b/nixos/modules/services/networking/bind.nix
@@ -229,9 +229,11 @@ in
 
     users.users.${bindUser} =
       {
-        uid = config.ids.uids.bind;
+        group = bindUser;
         description = "BIND daemon user";
+        isSystemUser = true;
       };
+    users.groups.${bindUser} = {};
 
     systemd.services.bind = {
       description = "BIND Domain Name Server";
diff --git a/nixos/modules/services/networking/consul.nix b/nixos/modules/services/networking/consul.nix
index ae7998913ee..476ca738dd1 100644
--- a/nixos/modules/services/networking/consul.nix
+++ b/nixos/modules/services/networking/consul.nix
@@ -159,10 +159,12 @@ in
 
       users.users.consul = {
         description = "Consul agent daemon user";
-        uid = config.ids.uids.consul;
+        isSystemUser = true;
+        group = "consul";
         # The shell is needed for health checks
         shell = "/run/current-system/sw/bin/bash";
       };
+      users.groups.consul = {};
 
       environment = {
         etc."consul.json".text = builtins.toJSON configOptions;
diff --git a/nixos/modules/services/networking/coturn.nix b/nixos/modules/services/networking/coturn.nix
index 5f7d2893ae2..12098ec6d33 100644
--- a/nixos/modules/services/networking/coturn.nix
+++ b/nixos/modules/services/networking/coturn.nix
@@ -311,6 +311,7 @@ in {
     {
       users.users.turnserver =
         { uid = config.ids.uids.turnserver;
+          group = "turnserver";
           description = "coturn TURN server user";
         };
       users.groups.turnserver =
diff --git a/nixos/modules/services/networking/dhcpd.nix b/nixos/modules/services/networking/dhcpd.nix
index 8966deac76c..54e4f900285 100644
--- a/nixos/modules/services/networking/dhcpd.nix
+++ b/nixos/modules/services/networking/dhcpd.nix
@@ -212,9 +212,11 @@ in
 
     users = {
       users.dhcpd = {
-        uid = config.ids.uids.dhcpd;
+        isSystemUser = true;
+        group = "dhcpd";
         description = "DHCP daemon user";
       };
+      groups.dhcpd = {};
     };
 
     systemd.services = dhcpdService "4" cfg4 // dhcpdService "6" cfg6;
diff --git a/nixos/modules/services/networking/dnsmasq.nix b/nixos/modules/services/networking/dnsmasq.nix
index 377d7bc5705..59a3ca2f28e 100644
--- a/nixos/modules/services/networking/dnsmasq.nix
+++ b/nixos/modules/services/networking/dnsmasq.nix
@@ -87,9 +87,11 @@ in
     services.dbus.packages = [ dnsmasq ];
 
     users.users.dnsmasq = {
-      uid = config.ids.uids.dnsmasq;
+      isSystemUser = true;
+      group = "dnsmasq";
       description = "Dnsmasq daemon user";
     };
+    users.groups.dnsmasq = {};
 
     networking.resolvconf = mkIf cfg.resolveLocalQueries {
       useLocalResolver = mkDefault true;
diff --git a/nixos/modules/services/networking/git-daemon.nix b/nixos/modules/services/networking/git-daemon.nix
index 98f80dd4bc4..6be72505c21 100644
--- a/nixos/modules/services/networking/git-daemon.nix
+++ b/nixos/modules/services/networking/git-daemon.nix
@@ -107,6 +107,7 @@ in
     users.users = optionalAttrs (cfg.user == "git") {
       git = {
         uid = config.ids.uids.git;
+        group = "git";
         description = "Git daemon user";
       };
     };
diff --git a/nixos/modules/services/networking/iodine.nix b/nixos/modules/services/networking/iodine.nix
index 46051d7044b..f67e2d9a5e7 100644
--- a/nixos/modules/services/networking/iodine.nix
+++ b/nixos/modules/services/networking/iodine.nix
@@ -190,6 +190,7 @@ in
 
     users.users.${iodinedUser} = {
       uid = config.ids.uids.iodined;
+      group = "iodined";
       description = "Iodine daemon user";
     };
     users.groups.iodined.gid = config.ids.gids.iodined;
diff --git a/nixos/modules/services/networking/morty.nix b/nixos/modules/services/networking/morty.nix
index e110a5c8610..c627feb527b 100644
--- a/nixos/modules/services/networking/morty.nix
+++ b/nixos/modules/services/networking/morty.nix
@@ -77,7 +77,9 @@ in
         createHome = true;
         home = "/var/lib/morty";
         isSystemUser = true;
+        group = "morty";
       };
+    users.groups.morty = {};
 
     systemd.services.morty =
       {
diff --git a/nixos/modules/services/networking/ncdns.nix b/nixos/modules/services/networking/ncdns.nix
index d30fe0f6f6d..c5ea5d95057 100644
--- a/nixos/modules/services/networking/ncdns.nix
+++ b/nixos/modules/services/networking/ncdns.nix
@@ -245,8 +245,10 @@ in
 
     users.users.ncdns = {
       isSystemUser = true;
+      group = "ncdns";
       description = "ncdns daemon user";
     };
+    users.groups.ncdns = {};
 
     systemd.services.ncdns = {
       description = "ncdns daemon";
diff --git a/nixos/modules/services/networking/networkmanager.nix b/nixos/modules/services/networking/networkmanager.nix
index c8861171dd6..ba13f575c39 100644
--- a/nixos/modules/services/networking/networkmanager.nix
+++ b/nixos/modules/services/networking/networkmanager.nix
@@ -464,6 +464,7 @@ in {
     users.users = {
       nm-openvpn = {
         uid = config.ids.uids.nm-openvpn;
+        group = "nm-openvpn";
         extraGroups = [ "networkmanager" ];
       };
       nm-iodine = {
diff --git a/nixos/modules/services/networking/ngircd.nix b/nixos/modules/services/networking/ngircd.nix
index 4b2fa779592..1b631de3b02 100644
--- a/nixos/modules/services/networking/ngircd.nix
+++ b/nixos/modules/services/networking/ngircd.nix
@@ -52,8 +52,11 @@ in {
     };
 
     users.users.ngircd = {
-      uid = config.ids.uids.ngircd;
+      isSystemUser = true;
+      group = "ngircd";
       description = "ngircd user.";
     };
+    users.groups.ngircd = {};
+
   };
 }
diff --git a/nixos/modules/services/networking/pleroma.nix b/nixos/modules/services/networking/pleroma.nix
index bd75083a4a7..93ab29b71e5 100644
--- a/nixos/modules/services/networking/pleroma.nix
+++ b/nixos/modules/services/networking/pleroma.nix
@@ -74,7 +74,7 @@ in {
       users."${cfg.user}" = {
         description = "Pleroma user";
         home = cfg.stateDir;
-        extraGroups = [ cfg.group ];
+        group = cfg.group;
         isSystemUser = true;
       };
       groups."${cfg.group}" = {};
diff --git a/nixos/modules/services/networking/radicale.nix b/nixos/modules/services/networking/radicale.nix
index 8c632c319d3..368259b5b0b 100644
--- a/nixos/modules/services/networking/radicale.nix
+++ b/nixos/modules/services/networking/radicale.nix
@@ -140,9 +140,12 @@ in {
 
     environment.systemPackages = [ pkg ];
 
-    users.users.radicale.uid = config.ids.uids.radicale;
+    users.users.radicale = {
+      isSystemUser = true;
+      group = "radicale";
+    };
 
-    users.groups.radicale.gid = config.ids.gids.radicale;
+    users.groups.radicale = {};
 
     systemd.services.radicale = {
       description = "A Simple Calendar and Contact Server";
diff --git a/nixos/modules/services/networking/radvd.nix b/nixos/modules/services/networking/radvd.nix
index 53fac4b7b72..6e8db55bbf0 100644
--- a/nixos/modules/services/networking/radvd.nix
+++ b/nixos/modules/services/networking/radvd.nix
@@ -55,9 +55,12 @@ in
   config = mkIf cfg.enable {
 
     users.users.radvd =
-      { uid = config.ids.uids.radvd;
+      {
+        isSystemUser = true;
+        group = "radvd";
         description = "Router Advertisement Daemon User";
       };
+    users.groups.radvd = {};
 
     systemd.services.radvd =
       { description = "IPv6 Router Advertisement Daemon";
diff --git a/nixos/modules/services/networking/smokeping.nix b/nixos/modules/services/networking/smokeping.nix
index 4470c18fd53..ef411767a94 100644
--- a/nixos/modules/services/networking/smokeping.nix
+++ b/nixos/modules/services/networking/smokeping.nix
@@ -259,7 +259,7 @@ in
       user = mkOption {
         type = types.str;
         default = "smokeping";
-        description = "User that runs smokeping and (optionally) thttpd";
+        description = "User that runs smokeping and (optionally) thttpd. A group of the same name will be created as well.";
       };
       webService = mkOption {
         type = types.bool;
@@ -285,11 +285,12 @@ in
     users.users.${cfg.user} = {
       isNormalUser = false;
       isSystemUser = true;
-      uid = config.ids.uids.smokeping;
+      group = cfg.user;
       description = "smokeping daemon user";
       home = smokepingHome;
       createHome = true;
     };
+    users.groups.${cfg.user} = {};
     systemd.services.smokeping = {
       wantedBy = [ "multi-user.target"];
       serviceConfig = {
diff --git a/nixos/modules/services/networking/ssh/sshd.nix b/nixos/modules/services/networking/ssh/sshd.nix
index 225aee51605..192533e52de 100644
--- a/nixos/modules/services/networking/ssh/sshd.nix
+++ b/nixos/modules/services/networking/ssh/sshd.nix
@@ -401,9 +401,12 @@ in
   config = mkIf cfg.enable {
 
     users.users.sshd =
-      { isSystemUser = true;
+      {
+        isSystemUser = true;
+        group = "sshd";
         description = "SSH privilege separation user";
       };
+    users.groups.sshd = {};
 
     services.openssh.moduliFile = mkDefault "${cfgc.package}/etc/ssh/moduli";
     services.openssh.sftpServerExecutable = mkDefault "${cfgc.package}/libexec/sftp-server";
diff --git a/nixos/modules/services/networking/tinydns.nix b/nixos/modules/services/networking/tinydns.nix
index 79507b2ebcd..2c44ad49296 100644
--- a/nixos/modules/services/networking/tinydns.nix
+++ b/nixos/modules/services/networking/tinydns.nix
@@ -32,7 +32,11 @@ with lib;
   config = mkIf config.services.tinydns.enable {
     environment.systemPackages = [ pkgs.djbdns ];
 
-    users.users.tinydns.isSystemUser = true;
+    users.users.tinydns = {
+      isSystemUser = true;
+      group = "tinydns";
+    };
+    users.groups.tinydns = {};
 
     systemd.services.tinydns = {
       description = "djbdns tinydns server";
diff --git a/nixos/modules/services/scheduling/atd.nix b/nixos/modules/services/scheduling/atd.nix
index 37f6651ec4c..9bb0191ee46 100644
--- a/nixos/modules/services/scheduling/atd.nix
+++ b/nixos/modules/services/scheduling/atd.nix
@@ -58,7 +58,9 @@ in
     security.pam.services.atd = {};
 
     users.users.atd =
-      { uid = config.ids.uids.atd;
+      {
+        uid = config.ids.uids.atd;
+        group = "atd";
         description = "atd user";
         home = "/var/empty";
       };
diff --git a/nixos/modules/services/search/kibana.nix b/nixos/modules/services/search/kibana.nix
index 2beb265ee5d..b3093abfa5c 100644
--- a/nixos/modules/services/search/kibana.nix
+++ b/nixos/modules/services/search/kibana.nix
@@ -199,10 +199,12 @@ in {
     environment.systemPackages = [ cfg.package ];
 
     users.users.kibana = {
-      uid = config.ids.uids.kibana;
+      isSystemUser = true;
       description = "Kibana service user";
       home = cfg.dataDir;
       createHome = true;
+      group = "kibana";
     };
+    users.groups.kibana = {};
   };
 }
diff --git a/nixos/modules/services/security/hockeypuck.nix b/nixos/modules/services/security/hockeypuck.nix
index 686634c8add..2e98624bb2e 100644
--- a/nixos/modules/services/security/hockeypuck.nix
+++ b/nixos/modules/services/security/hockeypuck.nix
@@ -82,8 +82,10 @@ in {
 
     users.users.hockeypuck = {
       isSystemUser = true;
+      group = "hockeypuck";
       description = "Hockeypuck user";
     };
+    users.groups.hockeypuck = {};
 
     systemd.services.hockeypuck = {
       description = "Hockeypuck OpenPGP Key Server";
diff --git a/nixos/modules/services/torrent/magnetico.nix b/nixos/modules/services/torrent/magnetico.nix
index 7465c10e002..ada6f9b1e3a 100644
--- a/nixos/modules/services/torrent/magnetico.nix
+++ b/nixos/modules/services/torrent/magnetico.nix
@@ -172,8 +172,10 @@ in {
 
     users.users.magnetico = {
       description = "Magnetico daemons user";
+      group = "magnetico";
       isSystemUser = true;
     };
+    users.groups.magnetico = {};
 
     systemd.services.magneticod = {
       description = "Magnetico DHT crawler";
diff --git a/nixos/modules/services/torrent/peerflix.nix b/nixos/modules/services/torrent/peerflix.nix
index a74f6598432..3e5f80960dc 100644
--- a/nixos/modules/services/torrent/peerflix.nix
+++ b/nixos/modules/services/torrent/peerflix.nix
@@ -60,6 +60,10 @@ in {
       };
     };
 
-    users.users.peerflix.uid = config.ids.uids.peerflix;
+    users.users.peerflix = {
+      isSystemUser = true;
+      group = "peerflix";
+    };
+    users.groups.peerflix = {};
   };
 }
diff --git a/nixos/modules/services/web-apps/node-red.nix b/nixos/modules/services/web-apps/node-red.nix
index 4f6850ace21..400790576d6 100644
--- a/nixos/modules/services/web-apps/node-red.nix
+++ b/nixos/modules/services/web-apps/node-red.nix
@@ -114,6 +114,7 @@ in
     users.users = optionalAttrs (cfg.user == defaultUser) {
       ${defaultUser} = {
         isSystemUser = true;
+        group = defaultUser;
       };
     };
 
diff --git a/nixos/modules/system/boot/systemd.nix b/nixos/modules/system/boot/systemd.nix
index 934c57f8391..6671592202f 100644
--- a/nixos/modules/system/boot/systemd.nix
+++ b/nixos/modules/system/boot/systemd.nix
@@ -1056,10 +1056,19 @@ in
 
     services.dbus.enable = true;
 
-    users.users.systemd-coredump.uid = config.ids.uids.systemd-coredump;
-    users.users.systemd-network.uid = config.ids.uids.systemd-network;
+    users.users.systemd-coredump = {
+      uid = config.ids.uids.systemd-coredump;
+      group = "systemd-coredump";
+    };
+    users.users.systemd-network = {
+      uid = config.ids.uids.systemd-network;
+      group = "systemd-network";
+    };
     users.groups.systemd-network.gid = config.ids.gids.systemd-network;
-    users.users.systemd-resolve.uid = config.ids.uids.systemd-resolve;
+    users.users.systemd-resolve = {
+      uid = config.ids.uids.systemd-resolve;
+      group = "systemd-resolve";
+    };
     users.groups.systemd-resolve.gid = config.ids.gids.systemd-resolve;
 
     # Target for ‘charon send-keys’ to hook into.
diff --git a/nixos/modules/virtualisation/lxd.nix b/nixos/modules/virtualisation/lxd.nix
index cde29f7bf59..6732e244369 100644
--- a/nixos/modules/virtualisation/lxd.nix
+++ b/nixos/modules/virtualisation/lxd.nix
@@ -158,7 +158,7 @@ in {
       };
     };
 
-    users.groups.lxd.gid = config.ids.gids.lxd;
+    users.groups.lxd = {};
 
     users.users.root = {
       subUidRanges = [ { startUid = 1000000; count = 65536; } ];