Simplify and improve flake.nix

flake.nix

@@ -1,39 +1,28 @@
 {
-  description = "JavaScript development environment";
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
 
-  inputs = {
-    nixpkgs.url = "github:NixOS/nixpkgs";
-  };
-
-  outputs = { self, nixpkgs }:
-    let
-      # Systems supported
-      allSystems = [
-        "x86_64-linux"
-        "aarch64-linux"
-        "x86_64-darwin"
-        "aarch64-darwin"
+  outputs = { self, nixpkgs }: let
+    system = "x86_64-linux";
+    pkgs = nixpkgs.legacyPackages.${system};
+  in {
+    devShells.${system}.default = pkgs.mkShell {
+      packages = with pkgs; [
+        nodejs_20
+        tree
       ];
-      
-      forAllSystems = f: nixpkgs.lib.genAttrs allSystems (system: f {
-        pkgs = nixpkgs.legacyPackages.${system};
-      });
-    in
-    {
-      packages = forAllSystems ({ pkgs }: {
-        default = pkgs.buildNpmPackage {
-          name = "build-aurora-blog";
-          buildInputs = with pkgs; [
-            nodejs_20
-          ];
-          src = ./.;
-          npmDepsHash = "sha256-hIfaaeKbS+Whav575OyIX1c9GoL6qks12zhHZB2w9IA=";
-          npmBuild = "npm run build";
-          installPhase = ''
-            mkdir $out
-            cp -r dist/* $out
-          '';
-        };
-      });
     };
+    packages.${system}.default = pkgs.buildNpmPackage {
+      name = "build-aurora-blog";
+      buildInputs = with pkgs; [
+        nodejs_20
+      ];
+      src = ./.;
+      npmDepsHash = "sha256-hIfaaeKbS+Whav575OyIX1c9GoL6qks12zhHZB2w9IA=";
+      npmBuild = "npm run build";
+      installPhase = ''
+        mkdir $out
+        cp -r dist/* $out
+      '';
+    };
+  };
 }