diff --git a/Bisecting-a-Regression.md b/Bisecting-a-Regression.md
index b246617..4d55c22 100644
--- a/Bisecting-a-Regression.md
+++ b/Bisecting-a-Regression.md
@@ -9,7 +9,7 @@ The minimum requirements are Git and Node.js.
 
 ### Using Node.js
 - Run `cd pdf.js`.
-- Run `gulp server`.
+- Run `npx gulp server`.
 - Open a browser and visit `http://localhost:8080/web/viewer.html`.
 
 ### Using another server