diff --git a/index.js b/index.js
index <HASH>..<HASH> 100644
--- a/index.js
+++ b/index.js
@@ -46,6 +46,6 @@ module.exports = function(env, callback) {
     callback(null, new NunjucksTemplate(nenv.getTemplate(filepath.relative)));
   };
 
-  env.registerTemplatePlugin("**/*.*(html|nunjucks)", NunjucksTemplate);
+  env.registerTemplatePlugin("**/*.*(html|nunjucks|njk)", NunjucksTemplate);
   callback();
 };
Support the official file extension .njk