refactor(flake)!: export packages using a flake module

Also stop passing `outputs` around, prefer `inputs.self`
Also put all `auto_` in `readOnly` `internal` options
- `autoModules`, `autoConfigurations` and `autoPackages`
Do not export packages as overlay (causes an infinite recursion)
- this is documented on the two places it has effect on
-- in `./overlays/default.nix` and `./modules/flake/configurations.nix`
-- in `autoConfigurations` we manually extend `pkgs` with the flake packages
Allow packages to say what `systems` they are compatible with
- See `./pkgs/swww/systems.nix` - disabled for all systems
- See `./pkgs/pngpaste/systems.nix` - enabled only for `darwin` targets

flake.nix

@@ -150,17 +150,20 @@
         ./modules/flake/agenix.nix
         ./modules/flake/deploy.nix
         ./modules/flake/topology
+        ./modules/flake/packages
       ];
 
-      perSystem = { lib, pkgs, system, ... }: {
-        # Packages (`nix build`)
-        packages = import ./pkgs { inherit pkgs; };
 
+      perSystem = { lib, pkgs, system, ... }: {
         # Apps (`nix run`)
         apps = import ./apps { inherit pkgs; };
 
         # Dev Shells (`nix develop`)
-        devShells = import ./shells { inherit pkgs inputs; };
+        devShells = import ./shells {
+          inherit inputs;
+          # NOTE: for `nixVersions.monitored`
+          pkgs = pkgs.extend inputs.self.overlays.modifications;
+        };
 
         # Formatter (`nix fmt`)
         formatter = pkgs.nixpkgs-fmt;
@@ -175,6 +178,9 @@
         # Automatic configurations, see `./modules/flake/configurations.nix`
         autoConfigurations.enableAll = true;
 
+        # Automatic packages, see `./modules/flake/packages/default.nix`
+        autoPackages.enable = true;
+
         # Templates
         templates = import ./templates {
           inherit inputs;

hosts/home-manager/x86_64-linux/__template__/home.nix

@@ -1,11 +1,11 @@
 # This is your home-manager configuration file
 # Use this to configure your home environment (it replaces ~/.config/nixpkgs/home.nix)
 
-{ inputs, outputs, lib, pkgs, config, ... }: {
+{ inputs, lib, pkgs, config, ... }: {
   # You can import other home-manager modules here
   imports = [
     # If you want to use modules your own flake exports (from modules/home-manager):
-    # outputs.homeManagerModules.example
+    # inputs.self.homeManagerModules.example
 
     # Or modules exported from other flakes (such as nix-colors):
     # inputs.nix-colors.homeManagerModules.default

hosts/nix-darwin/aarch64-darwin/limonka/configuration.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   environment.systemPackages = with pkgs; [ ];

hosts/nix-darwin/aarch64-darwin/limonka/home/pavelatanasov.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   home = {

hosts/nix-darwin/x86_64-darwin/apavel-a01/configuration.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   environment.systemPackages = with pkgs; [ ];

hosts/nix-darwin/x86_64-darwin/apavel-a01/home/apavel.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   home = {

hosts/nix-darwin/x86_64-darwin/limontozu/configuration.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   environment.systemPackages = with pkgs; [ ];

hosts/nix-darwin/x86_64-darwin/limontozu/home/pavelatanasov.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   home = {

hosts/nix-on-droid/aarch64-linux/cheetah/configuration.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   environment.packages = with pkgs; [ ];

hosts/nix-on-droid/aarch64-linux/cheetah/home.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   # Home Manager needs a bit of information about you and the

hosts/nixos/x86_64-linux/__template__/configuration.nix

@@ -1,11 +1,11 @@
 # This is your system's configuration file.
 # Use this to configure your system environment (it replaces /etc/nixos/configuration.nix)
 
-{ inputs, outputs, lib, pkgs, config, ... }: {
+{ inputs, lib, pkgs, config, ... }: {
   # You can import other NixOS modules here
   imports = [
     # If you want to use modules your own flake exports (from modules/nixos):
-    # outputs.nixosModules.example
+    # inputs.self.nixosModules.example
 
     # Or modules from other flakes (such as nixos-hardware):
     # inputs.hardware.nixosModules.common-cpu-amd
@@ -22,8 +22,8 @@
     # You can add overlays here
     overlays = [
       # If you want to use overlays your own flake exports (from overlays dir):
-      # outputs.overlays.modifications
-      # outputs.overlays.additions
+      # inputs.self.overlays.modifications
+      # inputs.self.overlays.additions
 
       # Or overlays exported from other flakes:
       # neovim-nightly-overlay.overlays.default

hosts/nixos/x86_64-linux/homix/configuration.nix

@@ -2,7 +2,7 @@
 # your system.  Help is available in the configuration.nix(5) man page
 # and in the NixOS manual (accessible by running ‘nixos-help’).
 
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   imports = [

hosts/nixos/x86_64-linux/homix/home/reo101.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   imports = [

hosts/nixos/x86_64-linux/jeeves/configuration.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 {
   imports = [
     inputs.hardware.nixosModules.common-cpu-amd

hosts/nixos/x86_64-linux/jeeves/disko.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 {
   imports = [
     inputs.disko.nixosModules.disko

hosts/nixos/x86_64-linux/jeeves/home-assistant/default.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 {
   environment.systemPackages = with pkgs; [
   ];

hosts/nixos/x86_64-linux/jeeves/home/jeeves.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   imports = [

hosts/nixos/x86_64-linux/jeeves/network.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 {
   environment.systemPackages = with pkgs; [
   ];

hosts/nixos/x86_64-linux/jeeves/nginx.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 
 {
   # age.secrets."nextcloud.adminpass" = {

hosts/nixos/x86_64-linux/jeeves/ollama.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 {
   networking.firewall.allowedTCPPorts = [11434];
 

hosts/nixos/x86_64-linux/jeeves/wireguard.nix

@@ -1,4 +1,4 @@
-{ inputs, outputs, lib, pkgs, config, ... }:
+{ inputs, lib, pkgs, config, ... }:
 {
   environment.systemPackages = with pkgs; [
     wireguard-tools

modules/flake/configurations.nix

@@ -1,19 +1,23 @@
 { lib, config, self, inputs, withSystem, ... }:
 
 let
-  outputs = self;
-  inherit (import ../../nix/utils.nix { inherit lib self; })
+  inherit (import ../../nix/utils.nix { inherit lib config self; })
     and
     hasFiles
     hasDirectories
     recurseDir
-    configuration-type-to-outputs-modules
-    configuration-type-to-outputs-hosts;
+    configuration-type-to-outputs-modules;
 in
 let
   # Configuration helpers
   configurationTypes = ["nixos" "nix-on-droid" "nix-darwin" "home-manager"];
 
+  # `pkgs` with flake's overlays
+  # NOTE: done here to avoid infinite recursion
+  pkgs' = system:
+    (withSystem system ({ pkgs, ... }: pkgs)).extend
+      (final: prev: inputs.self.packages.${system});
+
   homeManagerModule = { root, system, hostname, users ? null }: {
     home-manager = {
       # Use same `pkgs` instance as system (i.e. carry over overlays)
@@ -24,7 +28,7 @@ let
       sharedModules = builtins.attrValues config.flake.${configuration-type-to-outputs-modules "home-manager"};
       # Pass in `inputs`, `outputs` and maybe `meta`
       extraSpecialArgs = {
-        inherit inputs outputs;
+        inherit inputs;
         # TODO: meta?
         inherit hostname;
       };
@@ -42,7 +46,7 @@ let
 
   mkNixosHost = args @ { root, system, hostname, users }: inputs.nixpkgs.lib.nixosSystem {
     inherit system;
-    pkgs = withSystem system ({ pkgs, ... }: pkgs);
+    pkgs = pkgs' system;
 
     modules = [
       # Main configuration
@@ -62,14 +66,14 @@ let
     ] ++ (builtins.attrValues config.flake.${configuration-type-to-outputs-modules "nixos"});
 
     specialArgs = {
-      inherit inputs outputs;
+      inherit inputs;
     };
   };
 
   mkNixOnDroidHost = args @ { root, system, hostname }: inputs.nix-on-droid.lib.nixOnDroidConfiguration {
     # NOTE: inferred by `pkgs.system`
     # inherit system;
-    pkgs = withSystem system ({ pkgs, ... }: pkgs);
+    pkgs = pkgs' system;
 
     modules = [
       # Main configuration
@@ -79,15 +83,15 @@ let
     ] ++ (builtins.attrValues config.flake.${configuration-type-to-outputs-modules "nix-on-droid"});
 
     extraSpecialArgs = {
-      inherit inputs outputs;
+      inherit inputs;
     };
 
     home-manager-path = inputs.home-manager.outPath;
   };
 
   mkNixDarwinHost = args @ { root, system, hostname, users }: inputs.nix-darwin.lib.darwinSystem {
     inherit system;
-    pkgs = withSystem system ({ pkgs, ... }: pkgs);
+    pkgs = pkgs' system;
 
     modules = [
       # Main configuration
@@ -102,20 +106,20 @@ let
     ] ++ (builtins.attrValues config.flake.${configuration-type-to-outputs-modules "nix-darwin"});
 
     specialArgs = {
-      inherit inputs outputs;
+      inherit inputs;
     };
   };
 
   mkHomeManagerHost = args @ { root, system, hostname }: inputs.home-manager.lib.homeManagerConfiguration {
     inherit system;
-    pkgs = withSystem system ({ pkgs, ... }: pkgs);
+    pkgs = pkgs' system;
 
     modules = [
       "${root}/home.nix"
     ] ++ (builtins.attrValues config.flake.${configuration-type-to-outputs-modules "home-manager"});
 
     extraSpecialArgs = {
-      inherit inputs outputs;
+      inherit inputs;
       inherit hostname;
     };
   };
@@ -182,6 +186,20 @@ in
                         type = types.path;
                         default = "${submodule.config.baseDir}/${configurationType}";
                       };
+                      # TODO: split hosts and configurations?
+                      resultHosts = lib.mkOption {
+                        description = ''
+                          The resulting automatic packages
+                        '';
+                        # TODO: specify
+                        type = types.unspecified;
+                        readOnly = true;
+                        internal = true;
+                        default =
+                          lib.optionalAttrs
+                            config.flake.autoConfigurations.${configurationType}.enable
+                            (recurseDir config.flake.autoConfigurations.${configurationType}.dir);
+                      };
                     };
                   };
                   default = {};
@@ -194,21 +212,7 @@ in
   };
 
   config = {
-    flake = let
-      autoHosts =
-        lib.pipe
-          configurationTypes
-          [
-            (builtins.map
-              (configurationType:
-                lib.nameValuePair
-                  "${configuration-type-to-outputs-hosts configurationType}"
-                  (if config.flake.autoConfigurations.${configurationType}.enable
-                    then recurseDir config.flake.autoConfigurations.${configurationType}.dir
-                    else { })))
-            builtins.listToAttrs
-          ];
-    in autoHosts // {
+    flake = {
       # Configurations
       nixosConfigurations =
         createConfigurations
@@ -231,7 +235,7 @@ in
                 (lib.strings.removeSuffix ".nix")
                 (builtins.attrNames (configurationFiles."home" or { })));
             })
-          self.${configuration-type-to-outputs-hosts "nixos"};
+          config.flake.autoConfigurations.nixos.resultHosts;
 
       nixOnDroidConfigurations =
         createConfigurations
@@ -248,7 +252,7 @@ in
               inherit system;
               hostname = host;
             })
-          self.${configuration-type-to-outputs-hosts "nix-on-droid"};
+          config.flake.autoConfigurations.nix-on-droid.resultHosts;
 
       darwinConfigurations =
         createConfigurations
@@ -271,7 +275,7 @@ in
                 (lib.strings.removeSuffix ".nix")
                 (builtins.attrNames (configurationFiles."home" or { })));
             })
-          self.${configuration-type-to-outputs-hosts "nix-darwin"};
+          config.flake.autoConfigurations.nix-darwin.resultHosts;
 
       homeConfigurations =
         createConfigurations
@@ -288,7 +292,7 @@ in
               inherit system;
               hostname = host;
             })
-          self.${configuration-type-to-outputs-hosts "home-manager"};
+          config.flake.autoConfigurations.home-manager.resultHosts;
     };
   };
 }

modules/flake/deploy.nix

@@ -1,7 +1,7 @@
 { lib, config, self, inputs, ... }:
 
 let
-  inherit (import ../../nix/utils.nix { inherit lib self; })
+  inherit (import ../../nix/utils.nix { inherit lib config self; })
     accumulateHosts
     configuration-type-to-deploy-type;
 in