diff --git a/lib/errors/index.js b/lib/errors/index.js
index 921b2ff..425e995 100644
--- a/lib/errors/index.js
+++ b/lib/errors/index.js
@@ -56,5 +56,6 @@ traverseRoot(bitcore.Error, data);
 module.exports = bitcore.Error;
 
 module.exports.extend = function(spec) {
-  traverseRoot(bitcore.Error, spec);
+  traverseNode(bitcore.Error, spec);
+  return bitcore.Error;
 };