Reorganize imports to prevent infinite recursions

nixos-modules/default.nix

@@ -1,8 +1,9 @@
-inputs: {
+{ private, self, ... }:
+{
   default =
-    { config, pkgs, ... }:
+    { ... }:
     {
 
-      imports = (inputs.self.lib.loadSubmodulesFrom ./.) ++ [ inputs.private.nixosModules.default ];
+      imports = (self.lib.loadSubmodulesFrom ./.) ++ [ private.nixosModules.default ];
     };
 }

nixos-modules/nixpkgs-cache/default.nix

@@ -16,6 +16,7 @@ with lib;
     hostname = mkOption {
       type = types.str;
       example = "mycache.myhost.org";
+      default = "nixpkgs-cache.qo.is";
       description = "Hostname, under which the cache is served";
     };
 

nixos-modules/system/default.nix

@@ -57,7 +57,7 @@
     settings =
       let
         substituters = [
-          "https://${inputs.self.nixosConfigurations.lindberg-build.config.qois.nixpkgs-cache.hostname}?priority=39"
+          "https://${config.qois.nixpkgs-cache.hostname}?priority=39"
           "https://cache.nixos.org?priority=40"
           "https://attic.qo.is/qois-infrastructure"
         ];

nixos-modules/system/overlays.nix

@@ -7,6 +7,5 @@
 }:
 
 {
-  nixpkgs.overlays = [ (import ../../overlays) ];
   nix.nixPath = options.nix.nixPath.default;
 }