feat: Add Nix support

Creates symlinks to the relevant executables in the Nix store, for
integration with IDEs and other tools.

.gitignore

@@ -3,3 +3,6 @@ dist/
 cdk.out/
 cdk.context.json
 build/
+/helm
+/kubectl
+/node

shell.nix

@@ -0,0 +1,21 @@
+let
+  pkgs = import (
+    builtins.fetchTarball {
+      url = "https://github.com/nixos/nixpkgs/archive/d934204a0f8d9198e1e4515dd6fec76a139c87f0.tar.gz";
+      sha256 = "1zfby2jsfkag275aibp81bx1g1cc305qbcy94gqw0g6zki70k1lx";
+    }
+  ) {};
+in
+  pkgs.mkShell {
+    packages = [
+      pkgs.argo
+      pkgs.awscli2
+      pkgs.bashInteractive
+      pkgs.kubectl
+      pkgs.kubernetes-helm
+      pkgs.nodejs
+    ];
+    shellHook = ''
+      ln --force --symbolic "${pkgs.kubernetes-helm}/bin/helm" "${pkgs.kubectl}/bin/kubectl" "${pkgs.nodejs}/bin/node" .
+    '';
+  }