diff --git a/charts/cert-manager-webhook-gandi/shell.nix b/charts/cert-manager-webhook-gandi/shell.nix
new file mode 100644
index 0000000..9bdefef
--- /dev/null
+++ b/charts/cert-manager-webhook-gandi/shell.nix
@@ -0,0 +1,14 @@
+{ pkgs ? import <nixpkgs> {} }:
+
+let
+  unstable = import (builtins.fetchTarball {
+    name = "nixos-unstable-2021-09-12";
+    url = "https://github.com/nixos/nixpkgs/archive/2ce4d21663113020195f1d953e360213954645b3.tar.gz";
+    sha256 = "15pnbmm702a4ni8dm2jdwl46b20qw7gfm5chlrvn7w54cm3h9p0c";
+  }) {};
+in pkgs.mkShell {
+  buildInputs = with unstable; [
+    go_1_16
+    gopls
+  ];
+}