testing nix overlay 3

flake.nix

@@ -1,32 +1,43 @@
 {
   description = "swatch beat internet time";
+  
   inputs.nixpkgs.url = github:Nixos/nixpkgs/nixos-20.03;
+  
   outputs = { self, nixpkgs }: {
-    overlay = final: prev: {
-      swatch = with final; self.defaultPackage.x86_64-linux;
-    };
-    defaultPackage.x86_64-linux =
-      with import nixpkgs { system = "x86_64-linux"; };
-      stdenv.mkDerivation rec {
-        name = "swatch-${version}";
-        version = "1.0.0";
-        meta = {
-          description = "Display the current swatch beats";
-          longDescription = ''
-            Prints the current Swatch Internet Time.
-            Optional short form.
+    let
+      supportedSystems = [ "x86_64-linux" "i686-linux" "aarch64-linux" ];
+      forAllSystems =
+        f: nixpkgs.lib.genAttrs supportedSystems (system: f system);
+      version = "1.0.0";
+    in {
+
+      overlay = final: prev: {
+        swatch = with final; let nix = final.nix; in stdenv.mkDerivation {
+          name = "swatch-${version}";
+          buildInputs = [ gawk utillinux ];
+          src = self;
+          installPhase = ''
+            mkdir -p $out/bin
+            cp ./swatch.sh $out/bin/swatch
+            chmod +x $out/bin/swatch
           '';
-          homepage = https://github.com/techieAgnostic/swatch;
-          maintainers = [ "Shaun Kerr - s@p7.co.nz" ];
-          platforms = stdenv.lib.platforms.all;
+          meta = {
+            description = "Display the current swatch beats";
+            longDescription = ''
+              Prints the current Swatch Internet Time.
+              Optional short form.
+            '';
+            homepage = https://github.com/techieAgnostic/swatch;
+            maintainers = [ "Shaun Kerr - s@p7.co.nz" ];
+            platforms = stdenv.lib.platforms.all;
+          };
         };
-        src = self;
-        buildInputs = [
-          gawk
-          utillinux
-        ];
-        buildPhase = "cp ./swatch.sh ./swatch";
-        installPhase = "mkdir -p $out/bin; install -t $out/bin swatch";
       };
+
+      defaultPackage =
+        forAllSystems (system: (import nixpkgs {
+          inherit system;
+          overlays = [ self.overlay nix.overlay ];
+        }).swatch);
   };
 }