diff --git a/lib/js.dart b/lib/js.dart
index 2d6509e..3885c93 100644
--- a/lib/js.dart
+++ b/lib/js.dart
@@ -78,7 +78,7 @@
 #import('dart:isolate');
 
 // JavaScript bootstrapping code.
-final _JS_BOOTSTRAP = @"""
+final _JS_BOOTSTRAP = r"""
 (function() {
   // Proxy support