diff --git a/nix-darwin/default.nix b/nix-darwin/default.nix
index 9e37f3582..5966826ce 100644
--- a/nix-darwin/default.nix
+++ b/nix-darwin/default.nix
@@ -12,6 +12,7 @@ let
     specialArgs = {
       lib = extendedLib;
       darwinConfig = config;
+      osConfig = config;
     } // cfg.extraSpecialArgs;
     modules = [
       ({ name, ... }: {
diff --git a/nixos/default.nix b/nixos/default.nix
index ef51ac280..55016111d 100644
--- a/nixos/default.nix
+++ b/nixos/default.nix
@@ -12,6 +12,7 @@ let
     specialArgs = {
       lib = extendedLib;
       nixosConfig = config;
+      osConfig = config;
       modulesPath = ../modules;
     } // cfg.extraSpecialArgs;
     modules = [