diff --git a/modules/nix/default.nix b/modules/nix/default.nix
index b201a69..270bae4 100644
--- a/modules/nix/default.nix
+++ b/modules/nix/default.nix
@@ -156,6 +156,14 @@ let
     })
   ];
 
+  managedDefault = name: default: {
+    default = if cfg.enable then default else throw ''
+      ${name}: accessed when `nix.enable` is off; this is a bug in
+      nix-darwin or a third‐party module
+    '';
+    defaultText = default;
+  };
+
 in
 
 {
@@ -221,9 +229,7 @@ in
 
       package = mkOption {
         type = types.package;
-        default = warnIf (!cfg.enable)
-          "nix.package: accessed when `nix.enable` is off; this is a bug"
-          pkgs.nix;
+        inherit (managedDefault "nix.package" pkgs.nix) default;
         defaultText = literalExpression "pkgs.nix";
         description = ''
           This option specifies the Nix package instance to use throughout the system.
@@ -232,7 +238,7 @@ in
 
       distributedBuilds = mkOption {
         type = types.bool;
-        default = false;
+        inherit (managedDefault "nix.distributedBuilds" false) default defaultText;
         description = ''
           Whether to distribute builds to the machines listed in
           {option}`nix.buildMachines`.
@@ -242,7 +248,7 @@ in
       # Not in NixOS module
       daemonProcessType = mkOption {
         type = types.enum [ "Background" "Standard" "Adaptive" "Interactive" ];
-        default = "Standard";
+        inherit (managedDefault "nix.daemonProcessType" "Standard") default defaultText;
         description = ''
           Nix daemon process resource limits class. These limits propagate to
           build processes. `Standard` is the default process type
@@ -257,7 +263,7 @@ in
       # Not in NixOS module
       daemonIOLowPriority = mkOption {
         type = types.bool;
-        default = false;
+        inherit (managedDefault "nix.daemonIOLowPriority" false) default defaultText;
         description = ''
           Whether the Nix daemon process should considered to be low priority when
           doing file system I/O.
@@ -385,7 +391,7 @@ in
             };
           };
         });
-        default = [ ];
+        inherit (managedDefault "nix.buildMachines" [ ]) default defaultText;
         description = ''
           This option lists the machines to be used if distributed builds are
           enabled (see {option}`nix.distributedBuilds`).
@@ -399,12 +405,13 @@ in
       envVars = mkOption {
         type = types.attrs;
         internal = true;
-        default = { };
+        inherit (managedDefault "nix.envVars" { }) default defaultText;
         description = "Environment variables used by Nix.";
       };
 
       nrBuildUsers = mkOption {
         type = types.int;
+        inherit (managedDefault "nix.nrBuildUsers" 0) default defaultText;
         description = ''
           Number of `nixbld` user accounts created to
           perform secure concurrent builds.  If you receive an error
@@ -432,11 +439,13 @@ in
       # Definition differs substantially from NixOS module
       nixPath = mkOption {
         type = nixPathType;
-        default = lib.optionals cfg.channel.enable [
-          # Include default path <darwin-config>.
-          { darwin-config = "${config.environment.darwinConfig}"; }
-          "/nix/var/nix/profiles/per-user/root/channels"
-        ];
+        inherit (managedDefault "nix.nixPath" (
+          lib.optionals cfg.channel.enable [
+            # Include default path <darwin-config>.
+            { darwin-config = "${config.environment.darwinConfig}"; }
+            "/nix/var/nix/profiles/per-user/root/channels"
+          ]
+        )) default;
 
         defaultText = lib.literalExpression ''
           lib.optionals cfg.channel.enable [
@@ -458,7 +467,7 @@ in
 
       checkConfig = mkOption {
         type = types.bool;
-        default = true;
+        inherit (managedDefault "nix.checkConfig" true) default defaultText;
         description = ''
           If enabled (the default), checks for data type mismatches and that Nix
           can parse the generated nix.conf.
@@ -519,7 +528,7 @@ in
             };
           }
         ));
-        default = { };
+        inherit (managedDefault "nix.registry" { }) default defaultText;
         description = ''
           A system-wide flake registry.
         '';
@@ -527,7 +536,7 @@ in
 
       extraOptions = mkOption {
         type = types.lines;
-        default = "";
+        inherit (managedDefault "nix.extraOptions" "") default defaultText;
         example = ''
           keep-outputs = true
           keep-derivations = true
@@ -696,7 +705,7 @@ in
             };
           };
         };
-        default = { };
+        inherit (managedDefault "nix.settings" { }) default defaultText;
         description = ''
           Configuration for Nix, see
           <https://nixos.org/manual/nix/stable/#sec-conf-file>
diff --git a/tests/nix-enable.nix b/tests/nix-enable.nix
index 0828834..e052aa2 100644
--- a/tests/nix-enable.nix
+++ b/tests/nix-enable.nix
@@ -2,7 +2,6 @@
 
 {
   nix.enable = false;
-  nix.package = throw "`nix.package` used when `nix.enable` is turned off";
 
   test = ''
     printf >&2 'checking for unexpected Nix binary in /sw/bin\n'