Refactor host configs

hosts/odyssey/default.nix

@@ -7,35 +7,25 @@
     ../desktop.nix
   ];
 
-  boot.loader.systemd-boot = {
-    enable = true;
-    graceful = true;
-    netbootxyz.enable = true;
+  boot.loader = {
+    systemd-boot = {
+      enable = true;
+      graceful = true;
+      netbootxyz.enable = true;
+    };
+    efi.canTouchEfiVariables = true;
   };
-  boot.loader.efi.canTouchEfiVariables = true;
 
-  networking.hostName = "odyssey";
-  networking.hostId = "c5e68d78";
-  networking.networkmanager.enable = true;
+  networking = {
+    hostId = "c5e68d78";
+    networkmanager.enable = true;
+    firewall.trustedInterfaces = [ "lxdbr0" "virbr0" ]; # Work around https://github.com/NixOS/nixpkgs/issues/263359
+  };
 
-  nix.package = pkgs.nixFlakes;
-  nix.extraOptions = ''
-    experimental-features = nix-command flakes
-  '';
-
-  virtualisation.libvirtd.enable = true;
-  virtualisation.lxd.enable = true;
-  # Work around https://github.com/NixOS/nixpkgs/issues/263359
-  networking.firewall.trustedInterfaces = [ "lxdbr0" "virbr0" ];
-
-  users.defaultUserShell = pkgs.zsh;
-
-  system.stateVersion = "22.11";
-
-  services.journald.extraConfig = ''
-    SystemMaxUse=4G
-    MaxRetentionSec=90day
-  '';
+  virtualisation = {
+    libvirtd.enable = true;
+    lxd.enable = true;
+  };
 
   services.nix-serve = {
     enable = true;
@@ -101,4 +91,6 @@
       zsh.enable = true;
     };
   };
+
+  system.stateVersion = "22.11";
 }