fix: multi arch flake

flake.nix

@@ -1,37 +1,49 @@
 {
-  description = "ARM cross-compilation environment";
+  description = "Development Environment";
 
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.11";
+    flake-utils.url = "github:numtide/flake-utils";
   };
 
   outputs =
-    { self, nixpkgs }:
-    let
-      system = "x86_64-linux";
-      pkgs = nixpkgs.legacyPackages.${system};
+    { self
+    , nixpkgs
+    , flake-utils
+    ,
+    }:
+    flake-utils.lib.eachDefaultSystem (
+      system:
+      let
+        pkgs = (
+          import nixpkgs {
+            system = system;
+            config.allowUnfree = true;
+          }
+        );
 
-      oc = pkgs.writeShellScriptBin "oc" ''
-        PRJ_ROOT=$(git rev-parse --show-toplevel 2>/dev/null || pwd)
-        cd "$PRJ_ROOT" && OPENCODE_EXPERIMENTAL_LSP_TOOL=true opencode
-      '';
-    in
-    {
-      devShells.${system}.default = pkgs.mkShell {
-        buildInputs = with pkgs; [
-          # Backend
-          go
-          gopls
-          golangci-lint
+        oc = pkgs.writeShellScriptBin "oc" ''
+          PRJ_ROOT=$(git rev-parse --show-toplevel 2>/dev/null || pwd)
+          cd "$PRJ_ROOT" && OPENCODE_EXPERIMENTAL_LSP_TOOL=true opencode
+        '';
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          packages = with pkgs; [
+            # Backend
+            go
+            gopls
+            golangci-lint
 
-          # Frontend
-          bun
-          watchman
-          tailwindcss_4
+            # Frontend
+            bun
+            watchman
+            tailwindcss_4
 
-          # Custom Commands
-          oc
-        ];
-      };
-    };
+            # Custom Commands
+            oc
+          ];
+        };
+      }
+    );
 }