diff --git a/lib/hijack/instrument.js b/lib/hijack/instrument.js
index 87d5d222..e1a546ef 100644
--- a/lib/hijack/instrument.js
+++ b/lib/hijack/instrument.js
@@ -19,7 +19,7 @@ import { hijackDBOps } from './db';
 import { wrapRedisOplogObserveDriver } from './redis_oplog';
 
 let instrumented = false;
-Kadira._startInstrumenting = function (callback) {
+Kadira._startInstrumenting = function (callback = () => {}) {
   if (instrumented) {
     callback();
     return;