Incorporating @roberth 's suggestions

Author: pasqui23

doc/release-notes/index.rst

@@ -15,7 +15,9 @@ Release 2.0
 - Separate state backends for storing state.
 
 - Major code cleanups.
-  - Now network specification files can import other files via ``imports`` and ``requires`` is no longer supported.
+
+- Now the network specification is using the module system from ``nixpkgs.lib``
+  - Now network specification files can import other files via ``imports``.
   - We have a ``nodes.*`` option where we put every NixOS configuration for the configured nodes. We suggest to use it instead of defining nodes in the top level.
 
 - Removed NixOS Options

nix/eval-machine-info.nix

@@ -17,38 +17,37 @@ let
   flake = builtins.getFlake flakeUri;
   flakeExpr = (builtins.tryEval flake.outputs.nixopsConfigurations.default).value or { };
 
-  nixpkgs1 = <nixpkgs>; # this will be replaced on install by nixops' nixpkgs input
-  lib = import "${nixpkgs1}/lib";
+  nixpkgsBoot = <nixpkgs> ; # this will be replaced on install by nixops' nixpkgs input
+  libBoot = import "${nixpkgsBoot}/lib";
 
-  inherit (lib) mkOption types;
-
-  stage1Eval = lib.evalModules {
+  evalBoot = libBoot.evalModules {
     specialArgs = args;
     modules = [
-      (lib.mkRemovedOptionModule [ "require" ] "Use the imports option instead.")
       {
-        options.nixpkgs = mkOption {
-          type = types.path;
+        options.nixpkgs = libBoot.mkOption {
+          type = libBoot.types.path;
           description = "Path to the nixpkgs instance used to buld the machines.";
-          defaultText = lib.literalDocBook "The 'nixpkgs' input to either the provided flake or nixops' own.";
-          default = (builtins.tryEval flake.inputs.nixpkgs).value or nixpkgs1;
+          defaultText = libBoot.literalDocBook "The 'nixpkgs' input to either the provided flake or nixops' own.";
+          default = (builtins.tryEval flake.inputs.nixpkgs).value or nixpkgsBoot;
         };
-        config._module.freeformType = with types;attrsOf anything;
+        config._module.freeformType = with libBoot.types;attrsOf anything;
       }
       flakeExpr
     ] ++ networkExprs;
   };
 
-  inherit (stage1Eval.config) nixpkgs;
+  inherit (evalBoot.config) nixpkgs;
 
   pkgs = nixpkgs.legacyPackages.${system} or import nixpkgs { inherit system; };
+  lib = nixpkgs.lib or pkgs.lib or libBoot;
+  inherit (lib) mkOption types removeAttrs;
 
 in
 rec {
 
-  network = (stage1Eval.extendModules {
+  network = (evalBoot.extendModules {
     modules = [
-      ({ config, ... }: {
+      ({ config, options, ... }: {
         options = {
           network = {
             enableRollback = lib.mkEnableOption "network wide rollback";
@@ -107,27 +106,26 @@ rec {
             });
           };
           defaults = mkOption {
-            type = with types;
-              # TODO: use types.raw once this PR is merged: https://github.com/NixOS/nixpkgs/pull/132448
-              listOf (lib.mkOptionType {
-                name = "submodule";
-                inherit (submodule { }) check;
-                merge = lib.options.mergeOneOption;
-                description = "NixOS modules";
-              });
+            type = with types;listOf anything;
             default = [ ];
             description = ''
               Extra NixOS options to add to all nodes.
             '';
           };
         };
-        config.nodes = removeAttrs config [ "network" "defaults" "resources" "nodes" "nixpkgs" ];
+        config = let
+          nodes = removeAttrs config (builtins.attrNames options);
+        in mkIf ({} != nodes) { #TODO: actual warning/assert module impl.
+          nodes = lib.warn "Please use the actual nodes.* option instead of assigning machines to the config's top level" nodes;
+        };
       })
     ];
   }).config;
 
   inherit (network) defaults resources nodes;
 
+  networks = [ network ]; # for backward compatibility
+
   inherit nixpkgs;
 
   importedPluginNixExprs = map