add k3s

hosts/ess-helm/services/ess.nix

@@ -0,0 +1,24 @@
+{ config, pkgs, ... }:
+
+{
+  services.k3s = {
+    enable = true;
+    role = "server";
+    extraFlags = toString [
+      "--disable traefik"
+    ];
+  };
+
+  environment.systemPackages = with pkgs; [
+    kubectl
+    kubernetes-helm
+  ];
+
+  # TODO
+  # system.activationScripts.install-ess = {
+  #   text = ''
+  #     ${pkgs.kubernetes-helm}/bin/helm upgrade --install ess element-hq/element-server-suite -f /path/to/values.yaml -n ess --create-namespace
+  #   '';
+  #   deps = [ ];
+  # };
+}