Index: lib/tldjs.js
diff --git a/lib/tldjs.js b/lib/tldjs.js
index c354375b2fb223fc83c4472f642d4802a2b3d1b5..9106aa2161267a8d5889f7f1ab3f876148eb273f 100644
--- a/lib/tldjs.js
+++ b/lib/tldjs.js
@@ -17,6 +17,8 @@
 
 /** @module tldjs */
 
+"use strict";
+
 let getDomain =
 /**
  * Get the base domain for given hostname.
@@ -24,7 +26,7 @@ let getDomain =
  * @param {string} hostname
  * @return {string}
  */
-exports.getDomain = function(hostname)
+exports.getDomain = hostname =>
 {
   let bits = hostname.split(".");
   let cutoff = bits.length - 2;