diff --git a/flake.nix b/flake.nix
index 1232b74..e2c0ad8 100644
--- a/flake.nix
+++ b/flake.nix
@@ -39,7 +39,7 @@
       let
         pkgs = import nixpkgs {
           inherit system;
-          overlays = [ self.overlay ];
+          overlays = [ self.overlays.default ];
         };
         inherit (pkgs) lib;
       in
@@ -55,7 +55,7 @@
           };
         };
 
-        devShell = pkgs.mkShell {
+        devShells.default = pkgs.mkShell {
           name = "fablab-nixos-config";
 
           buildInputs = (with pkgs; [
@@ -112,7 +112,7 @@
               fablab;
           });
       }) // {
-      overlay = import ./pkgs;
+      overlays.default = import ./pkgs;
 
       nixosConfigurations = nixpkgs.lib.mapAttrs
         (hostname: { system
diff --git a/machines/party/hardware-configuration.nix b/machines/party/hardware-configuration.nix
index b32f461..a07aa08 100644
--- a/machines/party/hardware-configuration.nix
+++ b/machines/party/hardware-configuration.nix
@@ -21,7 +21,6 @@
 
     loader.grub = {
       enable = true;
-      version = 2;
       device = "/dev/sda";
     };
   };
diff --git a/machines/raven/services/dnsmasq.nix b/machines/raven/services/dnsmasq.nix
index 2610096..35faad7 100644
--- a/machines/raven/services/dnsmasq.nix
+++ b/machines/raven/services/dnsmasq.nix
@@ -20,40 +20,37 @@ in
 {
   services.dnsmasq = {
     enable = true;
-
-    extraConfig = ''
-      bind-dynamic
-      listen-address=192.168.93.1
-      listen-address=192.168.94.1
-      interface=lo
-
-      expand-hosts
-      domain=lab.fablab-nea.de
-      dhcp-range=192.168.93.20,192.168.93.254,4h
-      dhcp-range=192.168.94.20,192.168.94.254,4h
-
-      dhcp-boot=lpxelinux.0,raven,192.168.94.1
-
-      cache-size=10000
-      dns-forward-max=1000
-
-      auth-zone=lab.fablab-nea.de,192.168.94.0/24
-      auth-server=lab.fablab-nea.de,78.47.224.251
-
-      no-hosts
-      addn-hosts=${pkgs.writeText "hosts.dnsmasq" ''
+    settings = {
+      server = [
+        "142.250.185.78" # dns.as250.net
+        "2001:470:20::2" # ordns.he.net
+        "74.82.42.42" # ordns.he.net
+      ];
+      bind-dynamic = true;
+      listen-address = [
+        "192.168.93.1"
+        "192.168.94.1"
+      ];
+      interface = "lo";
+      expand-hosts = true;
+      domain = "lab.fablab-nea.de";
+      dhcp-range = [
+        "192.168.93.20,192.168.93.254,4h"
+        "192.168.94.20,192.168.94.254,4h"
+      ];
+      dhcp-boot = "lpxelinux.0,raven,192.168.94.1";
+      cache-size = 10000;
+      dns-forward-max = 1000;
+      auth-zone = "lab.fablab-nea.de,192.168.94.0/24";
+      auth-server = "lab.fablab-nea.de,78.47.224.251";
+      no-hosts = true;
+      addn-hosts = "${pkgs.writeText "hosts.dnsmasq" ''
         192.168.94.1 raven labsync unifi
         192.168.94.2 switch
         192.168.94.3 schneiderscheune-weinturm-ap
         192.168.94.4 schneiderscheune-weinturm-sta
-      ''}
-    '';
-
-    servers = [
-      "142.250.185.78" # dns.as250.net
-      "2001:470:20::2" # ordns.he.net
-      "74.82.42.42" # ordns.he.net
-    ];
+      ''}";
+    };
   };
 
   systemd.services."dnsmasq-events" = {
diff --git a/modules/base.nix b/modules/base.nix
index b233273..2755c93 100644
--- a/modules/base.nix
+++ b/modules/base.nix
@@ -1,3 +1,3 @@
 {
-  boot.cleanTmpDir = true;
+  boot.tmp.cleanOnBoot = true;
 }
diff --git a/modules/nix.nix b/modules/nix.nix
index 6a11112..e669255 100644
--- a/modules/nix.nix
+++ b/modules/nix.nix
@@ -34,11 +34,13 @@ in
       "nixpkgs-overlays=${overlaysCompat}"
     ];
 
-    # sudoers are trusted nix users
-    trustedUsers = [ "@wheel" ];
+    settings = {
+      # sudoers are trusted nix users
+      trusted-users = [ "@wheel" ];
 
-    # On-the-fly optimisation of nix store
-    autoOptimiseStore = true;
+      # On-the-fly optimisation of nix store
+      auto-optimise-store = true;
+    };
 
     # less noticeable nix builds
     daemonCPUSchedPolicy = "idle";
@@ -47,7 +49,7 @@ in
   };
 
   nixpkgs.overlays = with inputs; [
-    self.overlay
+    self.overlays.default
 
     (final: prev: {
       unstable = import nixpkgs-unstable {