nixos/nix-daemon: use structural settings

nixos/doc/manual/from_md/release-notes/rl-2205.section.xml

@@ -531,6 +531,29 @@
           was added.
         </para>
       </listitem>
+      <listitem>
+        <para>
+          The configuration portion of the <literal>nix-daemon</literal>
+          module has been reworked and exposed as
+          <link xlink:href="options.html#opt-nix-settings">nix.settings</link>:
+        </para>
+        <itemizedlist spacing="compact">
+          <listitem>
+            <para>
+              Legacy options have been mapped to the corresponding
+              options under under
+              <link xlink:href="options.html#opt-nix.settings">nix.settings</link>
+              but may be deprecated in the future.
+            </para>
+          </listitem>
+          <listitem>
+            <para>
+              <link xlink:href="options.html#opt-nix.buildMachines.publicHostKey">nix.buildMachines.publicHostKey</link>
+              has been added.
+            </para>
+          </listitem>
+        </itemizedlist>
+      </listitem>
       <listitem>
         <para>
           The

nixos/doc/manual/man-nixos-rebuild.xml

@@ -453,7 +453,7 @@
       Allow ad-hoc remote builders for building the new system. This requires
       the user executing <command>nixos-rebuild</command> (usually root) to be
       configured as a trusted user in the Nix daemon. This can be achieved by
-      using the <literal>nix.trustedUsers</literal> NixOS option. Examples
+      using the <literal>nix.settings.trusted-users</literal> NixOS option. Examples
       values for that option are described in the <literal>Remote builds
       chapter</literal> in the Nix manual, (i.e. <command>--builders
       "ssh://bigbrother x86_64-linux"</command>). By specifying an empty string

nixos/doc/manual/release-notes/rl-2205.section.md

@@ -183,6 +183,10 @@ In addition to numerous new and upgraded packages, this release has the followin
 
   Similarly [virtualisation.vmVariantWithBootloader](#opt-virtualisation.vmVariantWithBootLoader) was added.
 
+- The configuration portion of the `nix-daemon` module has been reworked and exposed as [nix.settings](options.html#opt-nix-settings):
+  * Legacy options have been mapped to the corresponding options under under [nix.settings](options.html#opt-nix.settings) but may be deprecated in the future.
+  * [nix.buildMachines.publicHostKey](options.html#opt-nix.buildMachines.publicHostKey) has been added.
+
 - The `writers.writePyPy2`/`writers.writePyPy3` and corresponding `writers.writePyPy2Bin`/`writers.writePyPy3Bin` convenience functions to create executable Python 2/3 scripts using the PyPy interpreter were added.
 
 - The `influxdb2` package was split into `influxdb2-server` and

nixos/maintainers/scripts/azure-new/examples/basic/system.nix

@@ -17,7 +17,7 @@ in
     description = "Azure NixOS Test User";
     openssh.authorizedKeys.keys = [ (builtins.readFile ~/.ssh/id_ed25519.pub) ];
   };
-  nix.trustedUsers = [ username ];
+  nix.settings.trusted-users = [ username ];
 
   virtualisation.azureImage.diskSize = 2500;
 

nixos/modules/installer/virtualbox-demo.nix

@@ -25,7 +25,7 @@ with lib;
 
   installer.cloneConfigExtra = ''
   # Let demo build as a trusted user.
-  # nix.trustedUsers = [ "demo" ];
+  # nix.settings.trusted-users = [ "demo" ];
 
   # Mount a VirtualBox shared folder.
   # This is configurable in the VirtualBox menu at

nixos/modules/profiles/hardened.nix

@@ -17,7 +17,7 @@ with lib;
 
   boot.kernelPackages = mkDefault pkgs.linuxPackages_hardened;
 
-  nix.allowedUsers = mkDefault [ "@users" ];
+  nix.settings.allowed-users = mkDefault [ "@users" ];
 
   environment.memoryAllocator.provider = mkDefault "scudo";
   environment.variables.SCUDO_OPTIONS = mkDefault "ZeroContents=1";

nixos/modules/security/misc.nix

@@ -123,8 +123,8 @@ with lib;
       boot.kernel.sysctl."user.max_user_namespaces" = 0;
 
       assertions = [
-        { assertion = config.nix.useSandbox -> config.security.allowUserNamespaces;
-          message = "`nix.useSandbox = true` conflicts with `!security.allowUserNamespaces`.";
+        { assertion = config.nix.settings.sandbox -> config.security.allowUserNamespaces;
+          message = "`nix.settings.sandbox = true` conflicts with `!security.allowUserNamespaces`.";
         }
       ];
     })

nixos/modules/services/continuous-integration/gitlab-runner.nix

@@ -147,7 +147,7 @@ in
     concurrent = mkOption {
       type = types.int;
       default = 1;
-      example = literalExpression "config.nix.maxJobs";
+      example = literalExpression "config.nix.settings.max-jobs";
       description = ''
         Limits how many jobs globally can be run concurrently.
         The most upper limit of jobs using all defined runners.

nixos/modules/services/continuous-integration/hercules-ci-agent/default.nix

@@ -67,7 +67,7 @@ in
 
     # Trusted user allows simplified configuration and better performance
     # when operating in a cluster.
-    nix.trustedUsers = [ config.systemd.services.hercules-ci-agent.serviceConfig.User ];
+    nix.settings.trusted-users = [ config.systemd.services.hercules-ci-agent.serviceConfig.User ];
     services.hercules-ci-agent = {
       settings = {
         nixUserIsTrusted = true;

nixos/modules/services/continuous-integration/hydra/default.nix

@@ -258,8 +258,6 @@ in
         uid = config.ids.uids.hydra-www;
       };
 
-    nix.trustedUsers = [ "hydra-queue-runner" ];
-
     services.hydra.extraConfig =
       ''
         using_frontend_proxy = 1
@@ -277,16 +275,21 @@ in
 
     environment.variables = hydraEnv;
 
-    nix.extraOptions = ''
-      keep-outputs = true
-      keep-derivations = true
-
-
-    '' + optionalString (versionOlder (getVersion config.nix.package.out) "2.4pre") ''
-      # The default (`true') slows Nix down a lot since the build farm
-      # has so many GC roots.
-      gc-check-reachability = false
-    '';
+    nix.settings = mkMerge [
+      {
+        keep-outputs = true;
+        keep-derivations = true;
+        trusted-users = [ "hydra-queue-runner" ];
+      }
+
+      (mkIf (versionOlder (getVersion config.nix.package.out) "2.4pre")
+        {
+          # The default (`true') slows Nix down a lot since the build farm
+          # has so many GC roots.
+          gc-check-reachability = false;
+        }
+      )
+    ];
 
     systemd.services.hydra-init =
       { wantedBy = [ "multi-user.target" ];