fix(hosts/defiant): streamline host definitions, skip library approach

In the previous configuration I used a library approach to generate
host configurations. This approach makes it more complicated to handle
different kind of host configurations and adds an unnecessary
abstraction layer.

Streamline the config defining darwin and nixos configurations directly
in the flake.

flake.nix

@@ -107,21 +107,15 @@
 
     # Build darwin flake using:
     # $ darwin-rebuild build --flake .#defiant
-
-    darwinConfigurations = let
-      system = "aarch64-darwin";
-      pkgs = pkgsFor.${system};
-    in {
-      defiant = import ./lib {
-        inherit
-          pkgs
-          nix-darwin
-          home-manager
-          system
-          user
-          flake
-          inputs
-          ;
+    darwinConfigurations = {
+      defiant = nix-darwin.lib.darwinSystem {
+        system = "aarch64-darwin";
+        modules = [./hosts/defiant];
+        specialArgs = {
+          inherit flake inputs;
+          system = "aarch64-darwin";
+          pkgs = pkgsFor.aarch64-darwin;
+        };
       };
     };
 

hosts/defiant/default.nix

@@ -0,0 +1,94 @@
+{
+  pkgs,
+  flake,
+  system,
+  inputs,
+  ...
+}: {
+  imports = [
+    inputs.home-manager.darwinModules.home-manager
+  ];
+
+  # List packages installed in system profile. To search by name, run:
+  # $ nix-env -qaP | grep wget
+  environment = {
+    systemPackages = [
+      pkgs.coreutils
+      pkgs.vim
+      pkgs.git
+    ];
+
+    shells = [
+      pkgs.bash
+      pkgs.zsh
+    ];
+
+    loginShell = pkgs.zsh;
+  };
+
+  fonts = {
+    packages = [
+      (pkgs.nerdfonts.override {
+        fonts = [
+          "JetBrainsMono"
+          "Meslo"
+        ];
+      })
+    ];
+  };
+
+  # Auto upgrade nix package and the daemon service.
+  services.nix-daemon.enable = true;
+
+  nix = {
+    # package = pkgs.nixVersions.nix_2_16;
+    checkConfig = true;
+    configureBuildUsers = true;
+    settings = {
+      # Necessary for using flakes on this system.
+      experimental-features = "nix-command flakes";
+      allowed-users = [
+        "@admin"
+      ];
+      # disable it, enabling leads to some symlink problems
+      # on macOS
+      auto-optimise-store = false;
+      cores = 6;
+      extra-sandbox-paths = [];
+      max-jobs = "auto";
+      require-sigs = true;
+      sandbox = false;
+      # substituters = [];
+      # trusted-public-keys = [];
+      trusted-users = [
+        "@admin"
+      ];
+    };
+  };
+
+  programs.zsh.enable = true;
+
+  # TODO https://discourse.nixos.org/t/give-name-label-comment-to-generations/45355
+  system.configurationRevision = flake.rev or flake.dirtyRev or null;
+
+  # Used for backwards compatibility,
+  # please read the changelog before changing.
+  # $ darwin-rebuild changelog
+  system.stateVersion = 4;
+
+  # The platform the configuration will be used on.
+  nixpkgs.hostPlatform = system;
+
+  networking = {
+    computerName = "defiant";
+    hostName = "defiant";
+    localHostName = "defiant";
+  };
+
+  home-manager = {
+    useGlobalPkgs = true;
+    useUserPackages = true;
+    extraSpecialArgs = {inherit pkgs;};
+    users.refnode = import ../../users/refnode;
+  };
+}

lib/default.nix

@@ -1,32 +1,2 @@
-{
-  pkgs,
-  nix-darwin,
-  home-manager,
-  system,
-  user,
-  flake,
-  inputs,
-  ...
-}: let
-  osConfig = ../hosts/darwin-base.nix;
-  userHomeConfig = ../users/${user};
-  systemFn = nix-darwin.lib.darwinSystem;
-  home-manager = inputs.home-manager.darwinModules.home-manager;
-in
-  systemFn {
-    modules = [
-      osConfig
-      {_module.args = {inherit flake;};}
-      home-manager
-      {
-        home-manager.useGlobalPkgs = true;
-        home-manager.useUserPackages = true;
-        home-manager.users.${user} = import userHomeConfig {
-          inherit pkgs user;
-        };
-        # Optionally, use home-manager.extraSpecialArgs to pass
-        # arguments to home.nix
-        # home-manager.extraSpecialArgs = { inherit lib; };
-      }
-    ];
-  }
+{...}: {
+}