ctucx.git: departures2mqtt

flake: refactor, remove `flake-utils` dependency

diff --git a/flake.lock b/flake.lock
@@ -1,20 +1,5 @@
 {
   "nodes": {
-    "flake-utils": {
-      "locked": {
-        "lastModified": 1667395993,
-        "narHash": "sha256-nuEHfE/LcWyuSWnS8t12N1wc105Qtau+/OdUAjtQ0rA=",
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "rev": "5aed5285a952e0b949eb3ba02c12fa4fcfef535f",
-        "type": "github"
-      },
-      "original": {
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "type": "github"
-      }
-    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1670772952,

@@ -33,7 +18,6 @@
     },
     "root": {
       "inputs": {
-        "flake-utils": "flake-utils",
         "nixpkgs": "nixpkgs"
       }
     }

diff --git a/flake.nix b/flake.nix
@@ -1,15 +1,33 @@
 {
+
   description = "Send kvg-kiel bus departures to mqtt";
 
-  inputs = {
-    flake-utils.url = "github:numtide/flake-utils";
-    nixpkgs.url     = "github:NixOS/nixpkgs/nixos-22.11";
-  };
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-22.11";
+
+  outputs = inputs: let
+    forAllSystems = function:
+      inputs.nixpkgs.lib.genAttrs [
+        "x86_64-linux"
+        "aarch64-linux"
+        "aarch64-darwin"
+      ] (system: function (import inputs.nixpkgs {
+        system   = system;
+        overlays = [ inputs.self.overlays.default ];
+      }));
 
-  outputs = { self, nixpkgs, flake-utils }: {
+  in {
 
-    overlay = final: prev: {
+    packages = forAllSystems (pkgs: {
+      default         = pkgs.departures2mqtt;
+      departures2mqtt = pkgs.departures2mqtt;
+    });
 
+    apps = forAllSystems (pkgs: {
+      default.type    = "app";
+      default.program = "${pkgs.departures2mqtt}/bin/departures2mqtt";
+    });
+
+    overlays.default = final: prev: {
       departures2mqtt = (
         let
           nmqtt = final.fetchFromGitHub {

@@ -20,35 +38,17 @@
           };
 
         in final.nimPackages.buildNimPackage {
-          name        = "departures2mqtt";
-          src         = self;
+          name = "departures2mqtt";
+          src  = inputs.self;
 
           buildInputs = [ nmqtt ];
 
-          nimBinOnly  = true;
-          nimRelease  = true;
+          nimBinOnly = true;
+          nimRelease = true;
         }
       );
-
     };
 
-  } // (flake-utils.lib.eachDefaultSystem (system:
-    let
-      pkgs = import nixpkgs {
-        inherit system;
-        overlays = [ self.overlay ];
-      };
-
-    in rec {
-
-      packages.default         = pkgs.departures2mqtt;
-      packages.departures2mqtt = pkgs.departures2mqtt;
-
-      apps.default = {
-        type = "app";
-        program = "${pkgs.departures2mqtt}/bin/departures2mqtt";
-      };
+  };
 
-    }
-  ));
-}-
\ No newline at end of file
+}