diff --git a/deps/chakrashim/lib/chakra_shim.js b/deps/chakrashim/lib/chakra_shim.js
index 4883f4dac71..bdd8bc6237c 100644
--- a/deps/chakrashim/lib/chakra_shim.js
+++ b/deps/chakrashim/lib/chakra_shim.js
@@ -19,11 +19,6 @@
 // IN THE SOFTWARE.
 'use strict';
 
-// CHAKRA-TODO doesn't implement the debugger. So add a dummy 'Debug' on
-// global object for now.
-Object.defineProperty(this, 'Debug',
-     { value: {}, enumerable: false, configurable: false, writable: false });
-
 (function() {
   // Save original builtIns
   var
diff --git a/deps/chakrashim/src/v8debug.cc b/deps/chakrashim/src/v8debug.cc
index e8e40dd8bd6..ce01fa416af 100644
--- a/deps/chakrashim/src/v8debug.cc
+++ b/deps/chakrashim/src/v8debug.cc
@@ -63,6 +63,23 @@ Local<Context> Debug::GetDebugContext() {
     HandleScope scope(isolate);
     g_debugContext = *Context::New(isolate);
     JsAddRef(g_debugContext, nullptr);
+
+    // CHAKRA-TODO: Chakra doesn't fully implement the debugger without
+    // --debug flag. Add a dummy 'Debug' on global object if it doesn't
+    // already exist.
+    {
+      Context::Scope context_scope(g_debugContext);
+      wchar_t * debugScript = L""
+        "if(this['Debug'] == undefined) { "
+           "Object.defineProperty(this, 'Debug', { value: {}, "
+                "enumerable : false, configurable : false, writable : false "
+            "}); "
+         "}";
+      JsValueRef result;
+      if (JsRunScript(debugScript, JS_SOURCE_CONTEXT_NONE, L"", &result) != JsNoError) {
+        return Local<Context>();
+      }
+    }
   }
 
   return static_cast<Context*>(g_debugContext);
diff --git a/test/parallel/test-cli-syntax.js b/test/parallel/test-cli-syntax.js
index e893a64b604..66ec9bb4202 100644
--- a/test/parallel/test-cli-syntax.js
+++ b/test/parallel/test-cli-syntax.js
@@ -55,9 +55,9 @@ var syntaxArgs = [
 
     // stderr should have a syntax error message
     var match = c.stderr.match(common.engineSpecificMessage({
-                                v8: /^SyntaxError: Unexpected identifier$/m,
-                                chakracore: /^SyntaxError: Expected ';'$/m})
-								);
+      v8: /^SyntaxError: Unexpected identifier$/m,
+      chakracore: /^SyntaxError: Expected ';'$/m})
+	);
     assert(match, 'stderr incorrect');
 
     assert.equal(c.status, 1, 'code == ' + c.status);