Add worker nodes.

nix/kubernetes/roles/containerd/default.nix

@@ -0,0 +1,46 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+{
+  imports = [ ];
+
+  options.me = {
+    containerd.enable = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+      example = true;
+      description = "Whether we want to install containerd.";
+    };
+  };
+
+  config = lib.mkIf config.me.containerd.enable {
+    virtualisation.containerd.enable = true;
+    virtualisation.containerd.settings = {
+      "plugins" = {
+        "io.containerd.grpc.v1.cri" = {
+          "cni" = {
+            "bin_dir" = "/opt/cni/bin";
+            "conf_dir" = "/etc/cni/net.d";
+          };
+          "containerd" = {
+            "default_runtime_name" = "runc";
+            "runtimes" = {
+              "runc" = {
+                "options" = {
+                  "SystemdCgroup" = true;
+                };
+                "runtime_type" = "io.containerd.runc.v2";
+              };
+            };
+            "snapshotter" = "overlayfs";
+          };
+        };
+      };
+      "version" = 2;
+    };
+  };
+}