Refactor host configs

hosts/common.nix

@@ -0,0 +1,81 @@
+{ config, lib, pkgs, ... }:
+
+{
+  time.timeZone = "Europe/London";
+
+  i18n.defaultLocale = "en_GB.UTF-8";
+  i18n.extraLocaleSettings = {
+    LC_ADDRESS = "en_GB.UTF-8";
+    LC_IDENTIFICATION = "en_GB.UTF-8";
+    LC_MEASUREMENT = "en_GB.UTF-8";
+    LC_MONETARY = "en_GB.UTF-8";
+    LC_NAME = "en_GB.UTF-8";
+    LC_NUMERIC = "en_GB.UTF-8";
+    LC_PAPER = "en_GB.UTF-8";
+    LC_TELEPHONE = "en_GB.UTF-8";
+    LC_TIME = "en_GB.UTF-8";
+  };
+  
+  console.keyMap = "uk";
+
+  security = {
+    auditd.enable = true;
+    audit = {
+      enable = true;
+      rules = [
+        "-a exit,always -F arch=b64 -S execve"
+      ];
+    };
+    sudo.execWheelOnly = true;
+  };
+
+  services.openssh = {
+    enable = true;
+    allowSFTP = false;
+    settings = {
+      KbdInteractiveAuthentication = false;
+      PasswordAuthentication = false;
+      PermitRootLogin = "no";
+    };
+  };
+
+  services.journald.extraConfig = ''
+    SystemMaxUse=4G
+    MaxRetentionSec=90day
+  '';
+
+  users.defaultUserShell = pkgs.zsh;
+
+  nix = {
+    package = pkgs.nixFlakes;
+    extraOptions = ''
+      experimental-features = nix-command flakes
+    '';
+    settings = {
+      connect-timeout = 5;
+      log-lines = 25;
+      min-free = 128000000;
+      max-free = 1000000000;
+      fallback = true;
+      allowed-users = [ "@wheel" ];
+      auto-optimise-store = true;
+      substituters = [
+        "http://odyssey.mesh.vimium.net"
+        "https://cache.nixos.org"
+      ];
+      trusted-public-keys = [
+        "odyssey.mesh.vimium.net:ZhQhjscPWjoN4rlZwoMELznEiBnZ9O26iyGA27ibilQ="
+      ];
+    };
+    gc = {
+      automatic = true;
+      dates = "weekly";
+      options = "-d --delete-older-than 7d";
+    };
+  };
+
+  environment.systemPackages = with pkgs; [
+    git
+    neovim
+  ];
+}