Dogfooding via partitions

flake.nix

@@ -44,6 +44,12 @@
             - a check with runCommand
           '';
         };
+        dogfood = {
+          path = ./template/dogfood;
+          description = ''
+            A minimal flake using flake-parts creating flake modules to build its own outputs.
+          '';
+        };
       };
       flakeModules = {
         easyOverlay = ./extras/easyOverlay.nix;
@@ -65,12 +71,6 @@
       flake = {
         inherit lib templates flakeModules;
       };
-      dogfood = {
-        path = ./template/dogfood;
-        description = ''
-          A minimal flake using flake-parts creating flake modules to build its own outputs.
-        '';
-      };
     };
 
 }

template/dogfood/flake.nix

@@ -9,13 +9,23 @@
     flake-parts.lib.mkFlake
       {
         inherit inputs;
-        moduleLocation = ./flake.nix;
       }
-      {
+      ({ config, lib, ... }: {
         imports = [
-          ./modules/anotherFlakeModule.nix
-          ./modules/hello.nix
+          flake-parts.flakeModules.partitions
           ./modules/dev.nix
         ];
-      };
+
+        systems = [ "x86_64-linux" "aarch64-darwin" ];
+
+        partitionedAttrs.devShells = "dogfood";
+        partitionedAttrs.packages = "dogfood";
+        partitions.dogfood = {
+          module = {
+            imports = [
+              config.flake.flakeModules.dev
+            ];
+          };
+        };
+      });
 }

template/dogfood/modules/anotherFlakeModule.nix

@@ -1,8 +0,0 @@
-{inputs, ...}: {
-  imports = [
-    inputs.flake-parts.flakeModules.flakeModules
-  ];
-  flake.flakeModules.anotherFlakeModule = {
-    # Define another flake module here
-  };
-}

template/dogfood/modules/custom-hello.nix

@@ -0,0 +1,19 @@
+{ inputs, flake-parts-lib, ... }:
+{
+  imports = [
+    inputs.flake-parts.flakeModules.flakeModules
+  ];
+
+  flake.flakeModules.customHello = {
+    options.perSystem = flake-parts-lib.mkPerSystemOption ({ pkgs, system, ... }: {
+      packages.hello =
+        (inputs.nixpkgs_23_05.legacyPackages.${system}.hello.override {
+          stdenv = pkgs.gcc11Stdenv;
+        }).overrideAttrs (oldAttrs: {
+          meta = oldAttrs.meta // {
+            description = "A hello package from the `flakeModules.customHello` author's nixpkgs 23.05, built with gcc 11 from `flakeModules.customHello` user's nixpkgs";
+          };
+        });
+    });
+  };
+}

template/dogfood/modules/dev.nix

@@ -1,28 +1,21 @@
-{flake-parts-lib, lib, inputs, ...}@topLevel:
-rec {
+{ flake-parts-lib, inputs, ... }@topLevel:
+{
   imports = [
     inputs.flake-parts.flakeModules.flakeModules
 
-    # Use file name to dogfood a flake module defined from the current flake to avoid infinite recursion
-    ./hello.nix
-
-    {
-      flake.flakeModules.dev.imports = [
-        # Use attributes to reference the flake module from other flakes
-        topLevel.config.flake.flakeModules.hello
-      ];
-    }
-
-    # Reference `flake.flakeModules.dev` via `rec` instead of `config` to avoid infinite recursion
-    flake.flakeModules.dev
+    # For `topLevel.config.flake.flakeModules.customHello`
+    ./custom-hello.nix
   ];
 
   flake.flakeModules.dev = {
-    config.systems = [ "x86_64-linux" "aarch64-darwin" ];
+    imports = [
+      # For `perSystem.config.packages.hello
+      topLevel.config.flake.flakeModules.customHello
+    ];
 
-    options.perSystem = flake-parts-lib.mkPerSystemOption ({pkgs, ...}@perSystem: {
+    options.perSystem = flake-parts-lib.mkPerSystemOption ({ pkgs, ... }@perSystem: {
       devShells.default = pkgs.mkShell {
-        buildInputs = [ perSystem.config.packages.hello_22_11 ];
+        buildInputs = [ perSystem.config.packages.hello ];
         shellHook = ''
           hello
         '';

template/dogfood/modules/hello.nix

@@ -1,16 +0,0 @@
-{inputs, flake-parts-lib, ...}:
-rec {
-  imports = [
-    inputs.flake-parts.flakeModules.flakeModules
-
-    # Reference `flake.flakeModules.hello` via `rec` instead of `config` to avoid infinite recursion
-    flake.flakeModules.hello
-  ];
-
-  flake.flakeModules.hello = {
-    options.perSystem = flake-parts-lib.mkPerSystemOption ({ system, ... }: {
-      packages.hello_22_11 =
-        inputs.nixpkgs_23_05.legacyPackages.${system}.hello;
-    });
-  };
-}