diff --git a/README.md b/README.md
new file mode 100644
index 0000000..666c891
--- /dev/null
+++ b/README.md
@@ -0,0 +1,5 @@
+# Nix Homelab
+This is the config of a nix based homelab server. Currently a work in progress.
+
+## Clustering with K3s
+K3s is a simplified version of Kubernetes. 
\ No newline at end of file
diff --git a/configuration.nix b/configuration.nix
index 919e44b..7f39490 100644
--- a/configuration.nix
+++ b/configuration.nix
@@ -10,6 +10,7 @@
     [ # Include the results of the hardware scan.
       ./hardware-configuration.nix
       ./homeassistant.nix
+      ./k3-cluster.nix
     ];
 
   # Bootloader.
@@ -136,7 +137,7 @@
     8123
     config.services.home-assistant.config.http.server_port
   ];
-  # networking.firewall.allowedUDPPorts = [ ... ];
+  networking.firewall.allowedUDPPorts = [];
   # Or disable the firewall altogether.
   # networking.firewall.enable = false;
 
diff --git a/k3-cluster.nix b/k3-cluster.nix
new file mode 100644
index 0000000..06bc85b
--- /dev/null
+++ b/k3-cluster.nix
@@ -0,0 +1,27 @@
+{
+  # For the first node:
+  services.k3s = {
+    enable = true;
+    role = "server";
+    token = "<randomized common secret>";
+    clusterInit = true;
+  };
+
+  # All subsequent nodes:
+  # services.k3s = {
+    # enable = true;
+    # role = "server"; # Or "agent" for worker only nodes
+    # token = "<randomized common secret";
+    # serverAddr = "https://<ip of first node>:6443";
+  # };
+
+  networking.firewall.allowedTCPPorts = [ 
+    6443
+    2379
+    2380
+  ];
+
+  networking.firewall.allowedUDPPorts = [ 
+    8472
+  ];
+}
\ No newline at end of file