diff --git a/deps/chakrashim/include/v8-debug.h b/deps/chakrashim/include/v8-debug.h
index 77de7d88421..52e424a36a5 100644
--- a/deps/chakrashim/include/v8-debug.h
+++ b/deps/chakrashim/include/v8-debug.h
@@ -91,7 +91,7 @@ class V8_EXPORT Debug {
   static Local<Context> GetDebugContext(Isolate* isolate);
 
   static void EnableDebug();
-  static void EnableInspector();
+  static void EnableInspector(bool enableReplayDebug = false);
 
   static void SetLiveEditEnabled(Isolate* isolate, bool enable);
 };
diff --git a/deps/chakrashim/src/inspector/inspector.gypi b/deps/chakrashim/src/inspector/inspector.gypi
index a240711fe8f..62e18a1d208 100644
--- a/deps/chakrashim/src/inspector/inspector.gypi
+++ b/deps/chakrashim/src/inspector/inspector.gypi
@@ -16,9 +16,12 @@
       '<(SHARED_INTERMEDIATE_DIR)/src/inspector/protocol/Runtime.h',
       '<(SHARED_INTERMEDIATE_DIR)/src/inspector/protocol/Schema.cpp',
       '<(SHARED_INTERMEDIATE_DIR)/src/inspector/protocol/Schema.h',
+      '<(SHARED_INTERMEDIATE_DIR)/src/inspector/protocol/TimeTravel.cpp',
+      '<(SHARED_INTERMEDIATE_DIR)/src/inspector/protocol/TimeTravel.h',
       '<(SHARED_INTERMEDIATE_DIR)/include/inspector/Debugger.h',
       '<(SHARED_INTERMEDIATE_DIR)/include/inspector/Runtime.h',
       '<(SHARED_INTERMEDIATE_DIR)/include/inspector/Schema.h',
+      '<(SHARED_INTERMEDIATE_DIR)/include/inspector/TimeTravel.h',
     ],
 
     'inspector_all_sources': [
@@ -65,6 +68,8 @@
       'src/inspector/v8-schema-agent-impl.h',
       'src/inspector/v8-stack-trace-impl.cc',
       'src/inspector/v8-stack-trace-impl.h',
+      'src/inspector/v8-timetravel-agent-impl.cc',
+      'src/inspector/v8-timetravel-agent-impl.h',
       'src/inspector/v8-value-copier.cc',
       'src/inspector/v8-value-copier.h',
     ]
diff --git a/deps/chakrashim/src/inspector/js_protocol.json b/deps/chakrashim/src/inspector/js_protocol.json
index e1c5e3e818d..1d6592983c6 100644
--- a/deps/chakrashim/src/inspector/js_protocol.json
+++ b/deps/chakrashim/src/inspector/js_protocol.json
@@ -777,5 +777,19 @@
                 "description": "Issued when new console message is added."
             }
         ]
+    },
+    {
+        "domain": "TimeTravel",
+        "description": "TimeTravel domain exposes JavaScript time travel capabilities. It allows stepping backwards through execution.",
+        "commands": [
+            {
+                "name": "stepBack",
+                "description": "Steps backwards to the previous statement."
+            },
+            {
+                "name": "reverse",
+                "description": "Resumes JavaScript execution in reverse."
+            }
+        ]
     }]
 }
diff --git a/deps/chakrashim/src/inspector/v8-debugger-agent-impl.cc b/deps/chakrashim/src/inspector/v8-debugger-agent-impl.cc
index a9f2e5ef927..c2744c26440 100644
--- a/deps/chakrashim/src/inspector/v8-debugger-agent-impl.cc
+++ b/deps/chakrashim/src/inspector/v8-debugger-agent-impl.cc
@@ -654,6 +654,20 @@ void V8DebuggerAgentImpl::stepOut(ErrorString* errorString) {
   m_debugger->stepOutOfFunction();
 }
 
+void V8DebuggerAgentImpl::reverse(ErrorString* errorString) {
+  if (!assertPaused(errorString)) return;
+  m_scheduledDebuggerStep = ReverseContinue;
+  m_steppingFromFramework = false;
+  m_debugger->reverse();
+}
+
+void V8DebuggerAgentImpl::stepBack(ErrorString* errorString) {
+  if (!assertPaused(errorString)) return;
+  m_scheduledDebuggerStep = StepBack;
+  m_steppingFromFramework = isTopPausedCallFrameBlackboxed();
+  m_debugger->stepBack();
+}
+
 void V8DebuggerAgentImpl::setPauseOnExceptions(
     ErrorString* errorString, const String16& stringPauseState) {
   if (!checkEnabled(errorString)) return;
diff --git a/deps/chakrashim/src/inspector/v8-debugger-agent-impl.h b/deps/chakrashim/src/inspector/v8-debugger-agent-impl.h
index 502336303af..3f2f533d2bc 100644
--- a/deps/chakrashim/src/inspector/v8-debugger-agent-impl.h
+++ b/deps/chakrashim/src/inspector/v8-debugger-agent-impl.h
@@ -110,6 +110,10 @@ class V8DebuggerAgentImpl : public protocol::Debugger::Backend {
       std::unique_ptr<protocol::Array<protocol::Debugger::ScriptPosition>>
           positions) override;
 
+  // Time travel implementations
+  void reverse(ErrorString*);
+  void stepBack(ErrorString*);
+
   bool enabled();
 
   void setBreakpointAt(const String16& scriptId, int lineNumber,
@@ -171,7 +175,14 @@ class V8DebuggerAgentImpl : public protocol::Debugger::Backend {
   using DebugServerBreakpointToBreakpointIdAndSourceMap =
       protocol::HashMap<String16, std::pair<String16, BreakpointSource>>;
 
-  enum DebuggerStep { NoStep = 0, StepInto, StepOver, StepOut };
+  enum DebuggerStep {
+    StepInto = 0,
+    StepOver,
+    StepOut,
+    StepBack,
+    ReverseContinue,
+    NoStep
+  };
 
   V8InspectorImpl* m_inspector;
   V8Debugger* m_debugger;
diff --git a/deps/chakrashim/src/inspector/v8-debugger.cc b/deps/chakrashim/src/inspector/v8-debugger.cc
index 3b69e8e9229..8b2e9f98772 100644
--- a/deps/chakrashim/src/inspector/v8-debugger.cc
+++ b/deps/chakrashim/src/inspector/v8-debugger.cc
@@ -256,6 +256,18 @@ void V8Debugger::clearStepping() {
   JsDiagSetStepType(JsDiagStepTypeContinue);
 }
 
+void V8Debugger::reverse() {
+  DCHECK(isPaused());
+  JsDiagSetStepType(JsDiagStepTypeReverseContinue);
+  continueProgram();
+}
+
+void V8Debugger::stepBack() {
+  DCHECK(isPaused());
+  JsDiagSetStepType(JsDiagStepTypeStepBack);
+  continueProgram();
+}
+
 bool V8Debugger::setScriptSource(
     const String16& sourceID, v8::Local<v8::String> newSource, bool dryRun,
     ErrorString* error,
diff --git a/deps/chakrashim/src/inspector/v8-debugger.h b/deps/chakrashim/src/inspector/v8-debugger.h
index 23fc2928d19..a0d7398bd11 100644
--- a/deps/chakrashim/src/inspector/v8-debugger.h
+++ b/deps/chakrashim/src/inspector/v8-debugger.h
@@ -58,6 +58,10 @@ class V8Debugger {
   void stepOutOfFunction();
   void clearStepping();
 
+  // Time travel
+  void reverse();
+  void stepBack();
+
   bool setScriptSource(const String16& sourceID,
                        v8::Local<v8::String> newSource, bool dryRun,
                        ErrorString*,
diff --git a/deps/chakrashim/src/inspector/v8-inspector-session-impl.cc b/deps/chakrashim/src/inspector/v8-inspector-session-impl.cc
index f9f77e95566..6846ac59e5a 100644
--- a/deps/chakrashim/src/inspector/v8-inspector-session-impl.cc
+++ b/deps/chakrashim/src/inspector/v8-inspector-session-impl.cc
@@ -16,6 +16,9 @@
 #include "src/inspector/v8-inspector-impl.h"
 #include "src/inspector/v8-runtime-agent-impl.h"
 #include "src/inspector/v8-schema-agent-impl.h"
+#include "src/inspector/v8-timetravel-agent-impl.h"
+
+#include "src/jsrtinspector.h"
 
 namespace v8_inspector {
 
@@ -28,7 +31,9 @@ bool V8InspectorSession::canDispatchMethod(const StringView& method) {
          stringViewStartsWith(method,
                               protocol::Console::Metainfo::commandPrefix) ||
          stringViewStartsWith(method,
-                              protocol::Schema::Metainfo::commandPrefix);
+                              protocol::Schema::Metainfo::commandPrefix) ||
+         stringViewStartsWith(method,
+                              protocol::TimeTravel::Metainfo::commandPrefix);
 }
 
 std::unique_ptr<V8InspectorSessionImpl> V8InspectorSessionImpl::create(
@@ -77,6 +82,11 @@ V8InspectorSessionImpl::V8InspectorSessionImpl(V8InspectorImpl* inspector,
       this, this, agentState(protocol::Schema::Metainfo::domainName)));
   protocol::Schema::Dispatcher::wire(&m_dispatcher, m_schemaAgent.get());
 
+  m_timeTravelAgent = wrapUnique(new V8TimeTravelAgentImpl(
+      this, this, agentState(protocol::TimeTravel::Metainfo::domainName)));
+  protocol::TimeTravel::Dispatcher::wire(&m_dispatcher,
+                                         m_timeTravelAgent.get());
+
   if (savedState.length()) {
     m_runtimeAgent->restore();
     m_debuggerAgent->restore();
@@ -173,6 +183,14 @@ V8InspectorSessionImpl::supportedDomainsImpl() {
                        .setName(protocol::Schema::Metainfo::domainName)
                        .setVersion(protocol::Schema::Metainfo::version)
                        .build());
+
+  if (m_timeTravelAgent->enabled()) {
+    result.push_back(protocol::Schema::Domain::create()
+                        .setName(protocol::TimeTravel::Metainfo::domainName)
+                        .setVersion(protocol::TimeTravel::Metainfo::version)
+                        .build());
+  }
+
   return result;
 }
 
diff --git a/deps/chakrashim/src/inspector/v8-inspector-session-impl.h b/deps/chakrashim/src/inspector/v8-inspector-session-impl.h
index d18eb00e398..68d2c68b5ac 100644
--- a/deps/chakrashim/src/inspector/v8-inspector-session-impl.h
+++ b/deps/chakrashim/src/inspector/v8-inspector-session-impl.h
@@ -22,6 +22,7 @@ class V8DebuggerAgentImpl;
 class V8InspectorImpl;
 class V8RuntimeAgentImpl;
 class V8SchemaAgentImpl;
+class V8TimeTravelAgentImpl;
 
 using protocol::ErrorString;
 
@@ -38,6 +39,7 @@ class V8InspectorSessionImpl : public V8InspectorSession,
   V8DebuggerAgentImpl* debuggerAgent() { return m_debuggerAgent.get(); }
   V8SchemaAgentImpl* schemaAgent() { return m_schemaAgent.get(); }
   V8RuntimeAgentImpl* runtimeAgent() { return m_runtimeAgent.get(); }
+  V8TimeTravelAgentImpl* timeTravelAgent() { return m_timeTravelAgent.get(); }
   int contextGroupId() const { return m_contextGroupId; }
 
   void reset();
@@ -85,6 +87,7 @@ class V8InspectorSessionImpl : public V8InspectorSession,
   std::unique_ptr<V8DebuggerAgentImpl> m_debuggerAgent;
   std::unique_ptr<V8ConsoleAgentImpl> m_consoleAgent;
   std::unique_ptr<V8SchemaAgentImpl> m_schemaAgent;
+  std::unique_ptr<V8TimeTravelAgentImpl> m_timeTravelAgent;
 
   DISALLOW_COPY_AND_ASSIGN(V8InspectorSessionImpl);
 };
diff --git a/deps/chakrashim/src/inspector/v8-timetravel-agent-impl.cc b/deps/chakrashim/src/inspector/v8-timetravel-agent-impl.cc
new file mode 100644
index 00000000000..11749391a5b
--- /dev/null
+++ b/deps/chakrashim/src/inspector/v8-timetravel-agent-impl.cc
@@ -0,0 +1,50 @@
+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "src/inspector/v8-timetravel-agent-impl.h"
+#include "src/inspector/v8-inspector-session-impl.h"
+#include "src/inspector/v8-debugger-agent-impl.h"
+#include "src/jsrtinspector.h"
+
+namespace v8_inspector {
+
+V8TimeTravelAgentImpl::V8TimeTravelAgentImpl(
+    V8InspectorSessionImpl* session, protocol::FrontendChannel* frontendChannel,
+    protocol::DictionaryValue* state)
+    : m_session(session),
+      m_frontend(frontendChannel),
+      m_state(state) {}
+
+V8TimeTravelAgentImpl::~V8TimeTravelAgentImpl() {}
+
+bool V8TimeTravelAgentImpl::checkEnabled(ErrorString* errorString) {
+  if (enabled()) {
+    return true;
+  }
+
+  *errorString = "TimeTravel agent is not enabled";
+  return false;
+}
+
+bool V8TimeTravelAgentImpl::enabled() {
+  return jsrt::Inspector::IsReplayDebugEnabled();
+}
+
+void V8TimeTravelAgentImpl::reverse(ErrorString* errorString) {
+  if (!checkEnabled(errorString)) {
+      return;
+  }
+
+  m_session->debuggerAgent()->reverse(errorString);
+}
+
+void V8TimeTravelAgentImpl::stepBack(ErrorString* errorString) {
+  if (!checkEnabled(errorString)) {
+      return;
+  }
+
+  m_session->debuggerAgent()->stepBack(errorString);
+}
+
+}  // namespace v8_inspector
diff --git a/deps/chakrashim/src/inspector/v8-timetravel-agent-impl.h b/deps/chakrashim/src/inspector/v8-timetravel-agent-impl.h
new file mode 100644
index 00000000000..4b3b001c4ec
--- /dev/null
+++ b/deps/chakrashim/src/inspector/v8-timetravel-agent-impl.h
@@ -0,0 +1,46 @@
+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef V8_INSPECTOR_V8TIMETRAVELAGENTIMPL_H_
+#define V8_INSPECTOR_V8TIMETRAVELAGENTIMPL_H_
+
+#include <vector>
+
+#include "src/base/macros.h"
+#include "src/inspector/protocol/TimeTravel.h"
+#include "src/inspector/protocol/Forward.h"
+
+namespace v8_inspector {
+
+class V8Debugger;
+class V8InspectorImpl;
+class V8InspectorSessionImpl;
+
+using protocol::ErrorString;
+
+class V8TimeTravelAgentImpl : public protocol::TimeTravel::Backend {
+ public:
+  V8TimeTravelAgentImpl(V8InspectorSessionImpl*, protocol::FrontendChannel*,
+                      protocol::DictionaryValue* state);
+  ~V8TimeTravelAgentImpl() override;
+
+  // Part of the protocol.
+  void reverse(ErrorString*) override;
+  void stepBack(ErrorString*) override;
+
+  bool enabled();
+
+ private:
+  bool checkEnabled(ErrorString*);
+
+  V8InspectorSessionImpl* m_session;
+  protocol::TimeTravel::Frontend m_frontend;
+  protocol::DictionaryValue* m_state;
+
+  DISALLOW_COPY_AND_ASSIGN(V8TimeTravelAgentImpl);
+};
+
+}  // namespace v8_inspector
+
+#endif  // V8_INSPECTOR_V8TIMETRAVELAGENTIMPL_H_
diff --git a/deps/chakrashim/src/jsrtinspector.cc b/deps/chakrashim/src/jsrtinspector.cc
index f46df4add0b..7f647cfeab3 100644
--- a/deps/chakrashim/src/jsrtinspector.cc
+++ b/deps/chakrashim/src/jsrtinspector.cc
@@ -26,6 +26,7 @@
 
 namespace v8 {
   extern THREAD_LOCAL bool g_EnableInspector;
+  extern THREAD_LOCAL bool g_EnableReplayDebug;
 }
 
 namespace jsrt {
@@ -159,6 +160,10 @@ namespace jsrt {
     return v8::g_EnableInspector;
   }
 
+  bool Inspector::IsReplayDebugEnabled() {
+    return v8::g_EnableReplayDebug;
+  }
+
   void Inspector::StartDebugging(JsRuntimeHandle runtime) {
     JsErrorCode errorCode = JsDiagStartDebugging(
       runtime, JsDiagDebugEventHandler, nullptr);
diff --git a/deps/chakrashim/src/jsrtinspector.h b/deps/chakrashim/src/jsrtinspector.h
index eede5c3ee15..065c9a3bce1 100644
--- a/deps/chakrashim/src/jsrtinspector.h
+++ b/deps/chakrashim/src/jsrtinspector.h
@@ -29,6 +29,7 @@ class InspectorBreakQueue;
 class Inspector {
  public:
   static bool IsInspectorEnabled();
+  static bool IsReplayDebugEnabled();
   static void StartDebugging(JsRuntimeHandle runtime);
   static void RequestAsyncBreak(JsRuntimeHandle runtime,
                                 v8::InterruptCallback callback,
diff --git a/deps/chakrashim/src/v8debug.cc b/deps/chakrashim/src/v8debug.cc
index 1b4462066b1..8915c3b45e3 100644
--- a/deps/chakrashim/src/v8debug.cc
+++ b/deps/chakrashim/src/v8debug.cc
@@ -25,13 +25,15 @@ namespace v8 {
 
   THREAD_LOCAL bool g_EnableDebug = false;
   THREAD_LOCAL bool g_EnableInspector = false;
+  THREAD_LOCAL bool g_EnableReplayDebug = false;
 
   void Debug::EnableDebug() {
     g_EnableDebug = true;
   }
 
-  void Debug::EnableInspector() {
+  void Debug::EnableInspector(bool enableReplayDebug) {
     g_EnableInspector = true;
+    g_EnableReplayDebug = enableReplayDebug;
   }
 
   Local<Context> Debug::GetDebugContext(Isolate* isolate) {
diff --git a/src/node.cc b/src/node.cc
index 9f6c02ee798..2e93896e3f9 100644
--- a/src/node.cc
+++ b/src/node.cc
@@ -4468,12 +4468,14 @@ void Init(int* argc,
   }
 #endif
 
-  // CHAKRA-TODO : fix this to not do it here
 #ifdef NODE_ENGINE_CHAKRACORE
+  // CHAKRA-TODO : fix this to not do it here
   if (debug_options.inspector_enabled()) {
+#if ENABLE_TTD_NODE
+    v8::Debug::EnableInspector(s_doTTReplay && s_doTTDebug);
+#else
     v8::Debug::EnableInspector();
-  } else if (debug_options.debugger_enabled()) {
-    v8::Debug::EnableDebug();
+#endif
   }
 #endif
 
@@ -4618,9 +4620,7 @@ inline int Start(Isolate* isolate, void* isolate_context,
   const char* path = argc > 1 ? argv[1] : nullptr;
   StartDebug(&env, path, debug_options);
 
-  bool debugger_enabled =
-      debug_options.debugger_enabled() || debug_options.inspector_enabled();
-  if (debugger_enabled && !debugger_running)
+  if (debug_options.inspector_enabled() && !debugger_running)
     return 12;  // Signal internal error.
 
   {
@@ -4638,10 +4638,6 @@ inline int Start(Isolate* isolate, void* isolate_context,
 
   env.set_trace_sync_io(trace_sync_io);
 
-  // Enable debugger
-  if (debug_options.debugger_enabled())
-    EnableDebug(&env);
-
   if (load_napi_modules) {
     ProcessEmitWarning(&env, "N-API is an experimental feature "
         "and could change at any time.");
@@ -4792,12 +4788,11 @@ inline int Start_TTDReplay(Isolate* isolate, void* isolate_context,
   Environment env(isolate_data, context);
   env.Start(argc, argv, exec_argc, exec_argv, v8_is_profiling);
 
-  bool debug_enabled =
-    debug_options.debugger_enabled() || debug_options.inspector_enabled();
-
   // Start debug agent when argv has --debug
-  if (debug_enabled)
-    StartDebug(&env, nullptr, debug_options);
+  StartDebug(&env, nullptr, debug_options);
+
+  if (debug_options.inspector_enabled() && !debugger_running)
+    return 12;  // Signal internal error.
 
   {
     Environment::AsyncCallbackScope callback_scope(&env);
@@ -4806,10 +4801,6 @@ inline int Start_TTDReplay(Isolate* isolate, void* isolate_context,
 
   env.set_trace_sync_io(trace_sync_io);
 
-  // Enable debugger
-  if (debug_enabled)
-    EnableDebug(&env);
-
   //// TTD Specific code
   JsTTDStart();