wip

flake.lock

@@ -1,5 +1,22 @@
 {
   "nodes": {
+    "harmonia": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1680542005,
+        "narHash": "sha256-fT9CJ/WAH5ESU4Ja062U/qNWDmhEfHI1XctnFjgBJ+A=",
+        "owner": "nix-community",
+        "repo": "harmonia",
+        "rev": "849a845c327ffb8fcc3322176479f6909f7a51a1",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-community",
+        "ref": "master",
+        "repo": "harmonia",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1681389457,
@@ -16,6 +33,7 @@
     },
     "root": {
       "inputs": {
+        "harmonia": "harmonia",
         "nixpkgs": "nixpkgs"
       }
     }

flake.nix

@@ -1,14 +1,29 @@
 {
   description = "Kefla POC";
 
-  outputs = { self, nixpkgs }:
+  inputs = {
+    harmonia = {
+      type = "github";
+      owner = "nix-community";
+      repo = "harmonia";
+      ref = "master";
+      flake = false;
+    };
+  };
+
+  outputs = { self, nixpkgs, ... }@inputs:
   let
-    kefla = import ./kefla nixpkgs;
+    kefla = import ./kefla inputs;
   in {
     packages = kefla {
+      # available on all achs
       package-all = ./package-all.nix;
+      # Darwin-only
       package-darwin = ./package-darwin.nix;
+      # Linux
       package-linux = ./package-linux.nix;
+      # Uses meta
+      package-flake-meta = ./package-flake-meta.nix;
     };
   };
 }

kefla/internal.nix

@@ -1,10 +1,10 @@
-nixpkgs:
+inputs:
 let
-  dummyPkgs = import nixpkgs { system = "x86_64-linux"; };
+  dummyPkgs = import inputs.nixpkgs { system = "x86_64-linux"; };
   lib = dummyPkgs.lib;
 in rec {
-  # Collects all the supported for drv leveraging the meta.platforms
-  # Nixpkgs attribute.
+  # Collects all the supported systems for drv leveraging the
+  # meta.platforms Nixpkgs attribute.
   #
   # We callPackage the derivation with a dummy Nixpkgs x86_64
   # instance, regardless of the underlying arch. It doesn't matter
@@ -37,16 +37,15 @@ in rec {
     let
       injectPlatformCallPackage = { attrs, platform }:
       let
-        pkgs = import nixpkgs { system = platform; };
-        callPackage = pkgs.lib.callPackageWith pkgs;
-      in builtins.mapAttrs (_name: value: callPackage value {}) attrs;
+        pkgs = import inputs.nixpkgs { system = platform; };
+      in builtins.mapAttrs (_name: value: pkgs.callPackage value { flakeMeta.inputs = inputs;}) attrs;
     in builtins.mapAttrs (name: value:
          injectPlatformCallPackage { attrs = value; platform = name; }) packages;
 
-  #
-
   kefla = packagesOutput:
   let
+    # We first generate the packages output like in its final form. We
+    # just lack the callPackage on the derivation path.
     packagesWithoutCallPackage = lib.foldlAttrs
       (acc: name: path:
         let

package-flake-meta.nix

@@ -0,0 +1,32 @@
+{ lib
+, stdenv
+, fetchurl
+, flakeMeta
+}:
+
+stdenv.mkDerivation (finalAttrs: {
+  pname = "hello";
+  version = "2.12.1";
+
+  src = fetchurl {
+    url = "mirror://gnu/hello/hello-${finalAttrs.version}.tar.gz";
+    sha256 = "sha256-jZkUKv2SV28wsM18tCqNxoCZmLxdYH2Idh9RLibH2yA=";
+  };
+
+  doCheck = true;
+
+  nativeBuildInputs = [ flakeMeta.inputs.harmonia ];
+
+  meta = with lib; {
+    description = "A program that produces a familiar, friendly greeting";
+    longDescription = ''
+      GNU Hello is a program that prints "Hello, world!" when you run it.
+      It is fully customizable.
+    '';
+    homepage = "https://www.gnu.org/software/hello/manual/";
+    changelog = "https://git.savannah.gnu.org/cgit/hello.git/plain/NEWS?h=v${finalAttrs.version}";
+    license = licenses.gpl3Plus;
+    maintainers = [ maintainers.eelco ];
+    platforms = platforms.all;
+  };
+})