Merge pull request #10 from redyf/dev

feat: Add devshell + formatter for CI/CD

flake.nix

@@ -38,7 +38,15 @@
     NixOS-WSL,
     spicetify-nix,
     ...
-  } @ inputs: {
+  } @ inputs: let
+    supportedSystems = ["x86_64-linux" "x86_64-darwin" "aarch64-linux" "aarch64-darwin"];
+
+    # Helper function to generate an attrset '{ x86_64-linux = f "x86_64-linux"; ... }'.
+    forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
+
+    # Nixpkgs instantiated for supported system types.
+    nixpkgsFor = forAllSystems (system: import nixpkgs {inherit system;});
+  in {
     nixosConfigurations = {
       redyf =
         nixpkgs.lib.nixosSystem
@@ -103,5 +111,18 @@
         ];
       };
     };
+    devShells = forAllSystems (system: let
+      pkgs = nixpkgsFor.${system};
+    in {
+      default = pkgs.mkShell {
+        buildInputs = with pkgs; [
+          git
+          nixpkgs-fmt
+          statix
+        ];
+      };
+    });
+
+    formatter.x86_64-linux = nixpkgs.legacyPackages.x86_64-linux.nixpkgs-fmt;
   };
 }