diff --git a/modules/installer/grub/grub.nix b/modules/installer/grub/grub.nix
index 97e5f12d048..73841b3778b 100644
--- a/modules/installer/grub/grub.nix
+++ b/modules/installer/grub/grub.nix
@@ -136,6 +136,14 @@ in
         '';
       };
 
+      ignoreDevicesCheck = mkOption {
+        default = false;
+        description = ''
+          (internal use) Don't throw an error when devices aren't given
+          useful for building nested child configurations
+        '';
+      };
+
       splashImage = mkOption {
         default =
           if config.boot.loader.grub.version == 1
@@ -197,7 +205,7 @@ in
 
     boot.loader.grub.devices = optional (cfg.device != "") cfg.device;
 
-    system.build = mkAssert (cfg.devices != [])
+    system.build = mkAssert (cfg.devices != [] || cfg.ignoreDevicesCheck)
       "You must set the ‘boot.loader.grub.device’ option to make the system bootable."
       { menuBuilder = grubMenuBuilder;
         inherit grub;
diff --git a/modules/system/activation/no-clone.nix b/modules/system/activation/no-clone.nix
index 74df217a01a..c78086466d1 100644
--- a/modules/system/activation/no-clone.nix
+++ b/modules/system/activation/no-clone.nix
@@ -6,8 +6,9 @@ with pkgs.lib;
 
 {
   boot.loader.grub.device = mkOverrideTemplate 0 {} "";
-  # undefined the obsolete name of the previous option.
+  # undefine the obsolete name of the previous option.
   boot.grubDevice = mkOverrideTemplate 0 {} pkgs.lib.mkNotdef;
+  boot.loader.grub.ignoreDevicesCheck = mkOverrideTemplate 0 {} true;
   nesting.children = mkOverrideTemplate 0 {} [];
   nesting.clone = mkOverrideTemplate 0 {} [];
 }