chore: add nix flake for k8s and go development

Signed-off-by: suin <[email protected]>

Author: suin

flake.lock

@@ -0,0 +1,31 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+        };
+
+        tools = with pkgs; [
+          kubectl
+          kind
+          go
+        ];
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          buildInputs = tools;
+          shellHook = ''
+            export KUBECONFIG="$(pwd)/.kube"
+          '';
+        };
+
+        formatter = pkgs.nixpkgs-fmt;
+      }
+    );
+}