Add bind service.

services/bind.nix

@@ -0,0 +1,29 @@
+# This Configuration is meant for local DNS setups only!
+{ options, config, lib, pkgs, ... }:
+
+with builtins;
+with lib;
+
+let
+  fn = import (../. + (toPath "/fn.nix")) { inherit lib; };
+  cfg = config.machine;
+in mkIf (elem "bind" cfg.services) {
+  services.bind = {
+    enable = true;
+    listenOn = [ "127.0.0.1" ];
+    forwarders = [
+      # Cloudflare CDN
+      "1.1.1.1" "1.0.0.1"
+      #CCC DNS
+      "204.152.184.76" "159.203.38.175" "207.148.83.241"
+    ];
+    # TODO: add DNSSEC
+    extraOptions = ''
+      dnssec-validation auto;
+
+      recursion yes;
+      allow-recursion { 127.0.0.1; };
+      version none;
+    '';
+  };
+}