diff --git a/spec/eientei/hass.nix b/spec/eientei/hass.nix
new file mode 100644
index 00000000..6c107b22
--- /dev/null
+++ b/spec/eientei/hass.nix
@@ -0,0 +1,20 @@
+{ pkgs
+, config
+, ...}: {
+  services.home-assistant = {
+    enable = true;
+    config = null;
+    configDir = "/nix/persist/service/hass";
+
+    extraComponents = [
+      "default_config"
+      "met"
+      "esphome"
+      "synology_dsm"
+    ];
+  };
+
+  nixpkgs.config.permittedInsecurePackages = [ "openssl-1.1.1w" ];
+
+  global.fs.zfs.mountpoints."/nix/persist/service/hass" = "service/hass";
+}