diff --git a/local-cli/server/middleware/getDevToolsMiddleware.js b/local-cli/server/middleware/getDevToolsMiddleware.js
index c47c697ff..f2ad3191e 100644
--- a/local-cli/server/middleware/getDevToolsMiddleware.js
+++ b/local-cli/server/middleware/getDevToolsMiddleware.js
@@ -14,8 +14,8 @@ const launchChrome = require('../util/launchChrome');
 
 const {exec} = require('child_process');
 
-function launchChromeDevTools(port) {
-  var debuggerURL = 'http://localhost:' + port + '/debugger-ui';
+function launchChromeDevTools(port, args = '') {
+  var debuggerURL = 'http://localhost:' + port + '/debugger-ui' + args;
   console.log('Launching Dev Tools...');
   launchChrome(debuggerURL);
 }
@@ -25,7 +25,10 @@ function escapePath(pathname) {
   return '"' + pathname + '"';
 }
 
-function launchDevTools({port, projectRoots}, isChromeConnected) {
+function launchDevTools(
+  {port, projectRoots, useDeltaBundler},
+  isChromeConnected,
+) {
   // Explicit config always wins
   var customDebugger = process.env.REACT_DEBUGGER;
   if (customDebugger) {
@@ -39,7 +42,7 @@ function launchDevTools({port, projectRoots}, isChromeConnected) {
     });
   } else if (!isChromeConnected()) {
     // Dev tools are not yet open; we need to open a session
-    launchChromeDevTools(port);
+    launchChromeDevTools(port, useDeltaBundler ? '#useDeltaBundler' : '');
   }
 }
 
diff --git a/local-cli/server/util/debugger-ui/index.html b/local-cli/server/util/debugger-ui/index.html
index c21a21892..f8867f5bc 100644
--- a/local-cli/server/util/debugger-ui/index.html
+++ b/local-cli/server/util/debugger-ui/index.html
@@ -206,6 +206,10 @@
   connectToDebuggerProxy();
 
   async function getBlobUrl(url) {
+    if (window.location.hash.indexOf('useDeltaBundler') === -1) {
+      return url;
+    }
+
     return await window.deltaUrlToBlobUrl(url.replace('.bundle', '.delta'));
   }
 })();