diff --git a/src/array-iterator.js b/src/array-iterator.js
index 9698a07b04..7c71e28100 100644
--- a/src/array-iterator.js
+++ b/src/array-iterator.js
@@ -10,6 +10,15 @@ var $arrayValues;
 
 %CheckIsBootstrapping();
 
+// -----------------------------------------------------------------------
+// Imports
+
+var arrayIterationKindSymbol =
+    utils.GetPrivateSymbol("array_iteration_kind_symbol");
+var arrayIteratorNextIndexSymbol =
+    utils.GetPrivateSymbol("array_iterator_next_symbol");
+var arrayIteratorObjectSymbol =
+    utils.GetPrivateSymbol("array_iterator_object_symbol");
 var GlobalArray = global.Array;
 
 macro TYPED_ARRAYS(FUNCTION)
@@ -30,10 +39,7 @@ endmacro
 
 TYPED_ARRAYS(COPY_FROM_GLOBAL)
 
-var arrayIteratorObjectSymbol = GLOBAL_PRIVATE("ArrayIterator#object");
-var arrayIteratorNextIndexSymbol = GLOBAL_PRIVATE("ArrayIterator#next");
-var arrayIterationKindSymbol = GLOBAL_PRIVATE("ArrayIterator#kind");
-
+// -----------------------------------------------------------------------
 
 function ArrayIterator() {}
 
diff --git a/src/bootstrapper.cc b/src/bootstrapper.cc
index dfedc7c9aa..30e10e63b5 100644
--- a/src/bootstrapper.cc
+++ b/src/bootstrapper.cc
@@ -13,6 +13,7 @@
 #include "src/extensions/gc-extension.h"
 #include "src/extensions/statistics-extension.h"
 #include "src/extensions/trigger-failure-extension.h"
+#include "src/heap/heap.h"
 #include "src/snapshot/natives.h"
 #include "src/snapshot/snapshot.h"
 #include "third_party/fdlibm/fdlibm.h"
@@ -1795,8 +1796,6 @@ void Bootstrapper::ImportNatives(Isolate* isolate, Handle<JSObject> container) {
   INSTALL_NATIVE(JSFunction, "URIError", uri_error_function);
   INSTALL_NATIVE(JSFunction, "MakeError", make_error_function);
 
-  INSTALL_NATIVE(Symbol, "promiseStatus", promise_status);
-  INSTALL_NATIVE(Symbol, "promiseValue", promise_value);
   INSTALL_NATIVE(JSFunction, "PromiseCreate", promise_create);
   INSTALL_NATIVE(JSFunction, "PromiseResolve", promise_resolve);
   INSTALL_NATIVE(JSFunction, "PromiseReject", promise_reject);
@@ -1907,6 +1906,21 @@ bool Bootstrapper::InstallJSBuiltins(Isolate* isolate,
 }
 
 
+void Bootstrapper::ExportPrivateSymbols(Isolate* isolate,
+                                        Handle<JSObject> container) {
+  HandleScope scope(isolate);
+#define EXPORT_PRIVATE_SYMBOL(NAME)                                         \
+  Handle<String> NAME##_name =                                              \
+      isolate->factory()->NewStringFromAsciiChecked(#NAME);                 \
+  JSObject::AddProperty(container, NAME##_name, isolate->factory()->NAME(), \
+                        NONE);
+
+  PRIVATE_SYMBOL_LIST(EXPORT_PRIVATE_SYMBOL)
+
+#undef EXPORT_PRIVATE_SYMBOL
+}
+
+
 #define EMPTY_INITIALIZE_GLOBAL_FOR_FEATURE(id) \
   void Genesis::InitializeGlobal_##id() {}
 
@@ -2789,24 +2803,6 @@ bool Genesis::InstallSpecialObjects(Handle<Context> native_context) {
     JSObject::AddProperty(global, natives_key, natives, DONT_ENUM);
   }
 
-  // Expose the stack trace symbol to native JS.
-  RETURN_ON_EXCEPTION_VALUE(isolate,
-                            JSObject::SetOwnPropertyIgnoreAttributes(
-                                handle(native_context->builtins(), isolate),
-                                factory->InternalizeOneByteString(
-                                    STATIC_CHAR_VECTOR("$stackTraceSymbol")),
-                                factory->stack_trace_symbol(), NONE),
-                            false);
-
-  // Expose the internal error symbol to native JS
-  RETURN_ON_EXCEPTION_VALUE(isolate,
-                            JSObject::SetOwnPropertyIgnoreAttributes(
-                                handle(native_context->builtins(), isolate),
-                                factory->InternalizeOneByteString(
-                                    STATIC_CHAR_VECTOR("$internalErrorSymbol")),
-                                factory->internal_error_symbol(), NONE),
-                            false);
-
   // Expose the debug global object in global if a name for it is specified.
   if (FLAG_expose_debug_as != NULL && strlen(FLAG_expose_debug_as) != 0) {
     // If loading fails we just bail out without installing the
diff --git a/src/bootstrapper.h b/src/bootstrapper.h
index 4a6503eae6..610610ba2b 100644
--- a/src/bootstrapper.h
+++ b/src/bootstrapper.h
@@ -123,6 +123,8 @@ class Bootstrapper final {
   static void ImportExperimentalNatives(Isolate* isolate,
                                         Handle<JSObject> container);
   static bool InstallJSBuiltins(Isolate* isolate, Handle<JSObject> container);
+  static void ExportPrivateSymbols(Isolate* isolate,
+                                   Handle<JSObject> container);
 
  private:
   Isolate* isolate_;
diff --git a/src/collection.js b/src/collection.js
index 6d43384e1c..07d7c5c61b 100644
--- a/src/collection.js
+++ b/src/collection.js
@@ -16,6 +16,7 @@ var $getExistingHash;
 var GlobalMap = global.Map;
 var GlobalObject = global.Object;
 var GlobalSet = global.Set;
+var hashCodeSymbol = utils.GetPrivateSymbol("hash_code_symbol");
 var IntRandom;
 
 utils.Import(function(from) {
@@ -90,8 +91,6 @@ function ComputeIntegerHash(key, seed) {
 }
 %SetForceInlineFlag(ComputeIntegerHash);
 
-var hashCodeSymbol = GLOBAL_PRIVATE("hash_code_symbol");
-
 function GetExistingHash(key) {
   if (%_IsSmi(key)) {
     return ComputeIntegerHash(key, 0);
diff --git a/src/contexts.h b/src/contexts.h
index 9e6fc0e4f5..edc5091a93 100644
--- a/src/contexts.h
+++ b/src/contexts.h
@@ -160,8 +160,6 @@ enum BindingFlags {
   V(TYPE_ERROR_FUNCTION_INDEX, JSFunction, type_error_function)                \
   V(URI_ERROR_FUNCTION_INDEX, JSFunction, uri_error_function)                  \
   V(MAKE_ERROR_FUNCTION_INDEX, JSFunction, make_error_function)                \
-  V(PROMISE_STATUS_INDEX, Symbol, promise_status)                              \
-  V(PROMISE_VALUE_INDEX, Symbol, promise_value)                                \
   V(PROMISE_CREATE_INDEX, JSFunction, promise_create)                          \
   V(PROMISE_RESOLVE_INDEX, JSFunction, promise_resolve)                        \
   V(PROMISE_REJECT_INDEX, JSFunction, promise_reject)                          \
diff --git a/src/debug/mirrors.js b/src/debug/mirrors.js
index f47a2d058e..1b45b93d8d 100644
--- a/src/debug/mirrors.js
+++ b/src/debug/mirrors.js
@@ -13,6 +13,8 @@ var GlobalArray = global.Array;
 var IsNaN = global.isNaN;
 var JSONStringify = global.JSON.stringify;
 var MathMin = global.Math.min;
+var promiseStatusSymbol = utils.GetPrivateSymbol("promise_status_symbol");
+var promiseValueSymbol = utils.GetPrivateSymbol("promise_value_symbol");
 var ToBoolean;
 var ToString;
 
@@ -109,7 +111,7 @@ function ClearMirrorCache(value) {
 function ObjectIsPromise(value) {
   try {
     return IS_SPEC_OBJECT(value) &&
-           !IS_UNDEFINED(%DebugGetProperty(value, builtins.$promiseStatus));
+           !IS_UNDEFINED(%DebugGetProperty(value, promiseStatusSymbol));
   } catch (e) {
     return false;
   }
@@ -1326,7 +1328,7 @@ inherits(PromiseMirror, ObjectMirror);
 
 
 function PromiseGetStatus_(value) {
-  var status = %DebugGetProperty(value, builtins.$promiseStatus);
+  var status = %DebugGetProperty(value, promiseStatusSymbol);
   if (status == 0) return "pending";
   if (status == 1) return "resolved";
   return "rejected";
@@ -1334,7 +1336,7 @@ function PromiseGetStatus_(value) {
 
 
 function PromiseGetValue_(value) {
-  return %DebugGetProperty(value, builtins.$promiseValue);
+  return %DebugGetProperty(value, promiseValueSymbol);
 }
 
 
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index eb5a609705..fbffd9f18b 100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -3392,19 +3392,6 @@ void Heap::CreateInitialObjects() {
 }
 
 
-void Heap::AddPrivateGlobalSymbols(Handle<Object> private_intern_table) {
-#define ADD_SYMBOL_TO_PRIVATE_INTERN_TABLE(name_arg)                     \
-  {                                                                      \
-    Handle<Symbol> symbol(Symbol::cast(roots_[k##name_arg##RootIndex])); \
-    Handle<String> name_arg##d(String::cast(symbol->name()));            \
-    JSObject::AddProperty(Handle<JSObject>::cast(private_intern_table),  \
-                          name_arg##d, symbol, NONE);                    \
-  }
-  PRIVATE_SYMBOL_LIST(ADD_SYMBOL_TO_PRIVATE_INTERN_TABLE)
-#undef ADD_SYMBOL_TO_PRIVATE_INTERN_TABLE
-}
-
-
 bool Heap::RootCanBeWrittenAfterInitialization(Heap::RootListIndex root_index) {
   switch (root_index) {
     case kStoreBufferTopRootIndex:
diff --git a/src/heap/heap.h b/src/heap/heap.h
index 80d29c4550..8691b1ae93 100644
--- a/src/heap/heap.h
+++ b/src/heap/heap.h
@@ -266,9 +266,6 @@ namespace internal {
   V(WeakSet_string, "WeakSet")                                 \
   V(for_string, "for")                                         \
   V(for_api_string, "for_api")                                 \
-  V(for_intern_string, "for_intern")                           \
-  V(private_api_string, "private_api")                         \
-  V(private_intern_string, "private_intern")                   \
   V(Date_string, "Date")                                       \
   V(char_at_string, "CharAt")                                  \
   V(undefined_string, "undefined")                             \
@@ -299,31 +296,47 @@ namespace internal {
   V(Error_string, "Error")                                     \
   V(RegExp_string, "RegExp")
 
-#define PRIVATE_SYMBOL_LIST(V)      \
-  V(nonextensible_symbol)           \
-  V(sealed_symbol)                  \
-  V(hash_code_symbol)               \
-  V(frozen_symbol)                  \
-  V(nonexistent_symbol)             \
-  V(elements_transition_symbol)     \
-  V(observed_symbol)                \
-  V(uninitialized_symbol)           \
-  V(megamorphic_symbol)             \
-  V(premonomorphic_symbol)          \
-  V(stack_trace_symbol)             \
-  V(detailed_stack_trace_symbol)    \
-  V(normal_ic_symbol)               \
-  V(home_object_symbol)             \
-  V(intl_initialized_marker_symbol) \
-  V(intl_impl_object_symbol)        \
-  V(promise_debug_marker_symbol)    \
-  V(promise_has_handler_symbol)     \
-  V(class_start_position_symbol)    \
-  V(class_end_position_symbol)      \
-  V(error_start_pos_symbol)         \
-  V(error_end_pos_symbol)           \
-  V(error_script_symbol)            \
-  V(internal_error_symbol)
+#define PRIVATE_SYMBOL_LIST(V)              \
+  V(array_iteration_kind_symbol)            \
+  V(array_iterator_next_symbol)             \
+  V(array_iterator_object_symbol)           \
+  V(call_site_function_symbol)              \
+  V(call_site_position_symbol)              \
+  V(call_site_receiver_symbol)              \
+  V(call_site_strict_symbol)                \
+  V(class_end_position_symbol)              \
+  V(class_start_position_symbol)            \
+  V(detailed_stack_trace_symbol)            \
+  V(elements_transition_symbol)             \
+  V(error_end_pos_symbol)                   \
+  V(error_script_symbol)                    \
+  V(error_start_pos_symbol)                 \
+  V(formatted_stack_trace_symbol)           \
+  V(frozen_symbol)                          \
+  V(hash_code_symbol)                       \
+  V(home_object_symbol)                     \
+  V(internal_error_symbol)                  \
+  V(intl_impl_object_symbol)                \
+  V(intl_initialized_marker_symbol)         \
+  V(megamorphic_symbol)                     \
+  V(nonexistent_symbol)                     \
+  V(nonextensible_symbol)                   \
+  V(normal_ic_symbol)                       \
+  V(observed_symbol)                        \
+  V(premonomorphic_symbol)                  \
+  V(promise_debug_marker_symbol)            \
+  V(promise_has_handler_symbol)             \
+  V(promise_on_resolve_symbol)              \
+  V(promise_on_reject_symbol)               \
+  V(promise_raw_symbol)                     \
+  V(promise_status_symbol)                  \
+  V(promise_value_symbol)                   \
+  V(sealed_symbol)                          \
+  V(stack_trace_symbol)                     \
+  V(string_iterator_iterated_string_symbol) \
+  V(string_iterator_next_index_symbol)      \
+  V(uninitialized_symbol)
+
 
 #define PUBLIC_SYMBOL_LIST(V)                                    \
   V(has_instance_symbol, symbolHasInstance, Symbol.hasInstance)  \
@@ -1805,8 +1818,6 @@ class Heap {
   static const ConstantStringTable constant_string_table[];
   static const StructTable struct_table[];
 
-  void AddPrivateGlobalSymbols(Handle<Object> private_intern_table);
-
   struct GCCallbackPair {
     GCCallbackPair(v8::Isolate::GCCallback callback, GCType gc_type,
                    bool pass_isolate)
diff --git a/src/isolate.cc b/src/isolate.cc
index b6c5da02ac..6ff7d47db6 100644
--- a/src/isolate.cc
+++ b/src/isolate.cc
@@ -2561,9 +2561,6 @@ Handle<JSObject> Isolate::GetSymbolRegistry() {
     SetUpSubregistry(registry, map, "for");
     SetUpSubregistry(registry, map, "for_api");
     SetUpSubregistry(registry, map, "keyFor");
-    SetUpSubregistry(registry, map, "private_api");
-    heap()->AddPrivateGlobalSymbols(
-        SetUpSubregistry(registry, map, "private_intern"));
   }
   return Handle<JSObject>::cast(factory()->symbol_registry());
 }
diff --git a/src/macros.py b/src/macros.py
index 49b2cad8bd..2cf9372410 100644
--- a/src/macros.py
+++ b/src/macros.py
@@ -159,14 +159,11 @@ macro SHOULD_CREATE_WRAPPER(functionName, receiver) = (!IS_SPEC_OBJECT(receiver)
 macro HAS_INDEX(array, index, is_array) = ((is_array && %_HasFastPackedElements(%IS_VAR(array))) ? (index < array.length) : (index in array));
 
 # Private names.
-macro GLOBAL_PRIVATE(name) = (%CreateGlobalPrivateSymbol(name));
-macro NEW_PRIVATE(name) = (%CreatePrivateSymbol(name));
 macro IS_PRIVATE(sym) = (%SymbolIsPrivate(sym));
 macro HAS_PRIVATE(obj, sym) = (%HasOwnProperty(obj, sym));
 macro HAS_DEFINED_PRIVATE(obj, sym) = (!IS_UNDEFINED(obj[sym]));
 macro GET_PRIVATE(obj, sym) = (obj[sym]);
 macro SET_PRIVATE(obj, sym, val) = (obj[sym] = val);
-macro DELETE_PRIVATE(obj, sym) = (delete obj[sym]);
 
 # Constants.  The compiler constant folds them.
 define NAN = $NaN;
diff --git a/src/messages.cc b/src/messages.cc
index 6683443e52..908ee08e4b 100644
--- a/src/messages.cc
+++ b/src/messages.cc
@@ -138,37 +138,50 @@ base::SmartArrayPointer<char> MessageHandler::GetLocalizedMessage(
 }
 
 
-Handle<Object> CallSite::GetFileName(Isolate* isolate) {
-  Handle<Object> script(fun_->shared()->script(), isolate);
-  if (script->IsScript()) {
-    return Handle<Object>(Handle<Script>::cast(script)->name(), isolate);
-  }
-  return isolate->factory()->null_value();
+CallSite::CallSite(Isolate* isolate, Handle<JSObject> call_site_obj)
+    : isolate_(isolate) {
+  receiver_ = JSObject::GetDataProperty(
+      call_site_obj, isolate->factory()->call_site_receiver_symbol());
+  fun_ = Handle<JSFunction>::cast(JSObject::GetDataProperty(
+      call_site_obj, isolate->factory()->call_site_function_symbol()));
+  pos_ = Handle<Smi>::cast(JSObject::GetDataProperty(
+                               call_site_obj,
+                               isolate->factory()->call_site_position_symbol()))
+             ->value();
 }
 
 
-Handle<Object> CallSite::GetFunctionName(Isolate* isolate) {
+Handle<Object> CallSite::GetFileName() {
+  Handle<Object> script(fun_->shared()->script(), isolate_);
+  if (script->IsScript()) {
+    return Handle<Object>(Handle<Script>::cast(script)->name(), isolate_);
+  }
+  return isolate_->factory()->null_value();
+}
+
+
+Handle<Object> CallSite::GetFunctionName() {
   Handle<String> result = JSFunction::GetDebugName(fun_);
   if (result->length() != 0) return result;
-  Handle<Object> script(fun_->shared()->script(), isolate);
+  Handle<Object> script(fun_->shared()->script(), isolate_);
   if (script->IsScript() &&
       Handle<Script>::cast(script)->compilation_type() ==
           Script::COMPILATION_TYPE_EVAL) {
-    return isolate->factory()->eval_string();
+    return isolate_->factory()->eval_string();
   }
-  return isolate->factory()->null_value();
+  return isolate_->factory()->null_value();
 }
 
 
-Handle<Object> CallSite::GetScriptNameOrSourceUrl(Isolate* isolate) {
-  Handle<Object> script_obj(fun_->shared()->script(), isolate);
+Handle<Object> CallSite::GetScriptNameOrSourceUrl() {
+  Handle<Object> script_obj(fun_->shared()->script(), isolate_);
   if (script_obj->IsScript()) {
     Handle<Script> script = Handle<Script>::cast(script_obj);
     Object* source_url = script->source_url();
-    if (source_url->IsString()) return Handle<Object>(source_url, isolate);
-    return Handle<Object>(script->name(), isolate);
+    if (source_url->IsString()) return Handle<Object>(source_url, isolate_);
+    return Handle<Object>(script->name(), isolate_);
   }
-  return isolate->factory()->null_value();
+  return isolate_->factory()->null_value();
 }
 
 
@@ -190,25 +203,25 @@ bool CheckMethodName(Isolate* isolate, Handle<JSObject> obj, Handle<Name> name,
 }
 
 
-Handle<Object> CallSite::GetMethodName(Isolate* isolate) {
-  MaybeHandle<JSReceiver> maybe = Object::ToObject(isolate, receiver_);
+Handle<Object> CallSite::GetMethodName() {
+  MaybeHandle<JSReceiver> maybe = Object::ToObject(isolate_, receiver_);
   Handle<JSReceiver> receiver;
   if (!maybe.ToHandle(&receiver) || !receiver->IsJSObject()) {
-    return isolate->factory()->null_value();
+    return isolate_->factory()->null_value();
   }
 
   Handle<JSObject> obj = Handle<JSObject>::cast(receiver);
-  Handle<Object> function_name(fun_->shared()->name(), isolate);
+  Handle<Object> function_name(fun_->shared()->name(), isolate_);
   if (function_name->IsName()) {
     Handle<Name> name = Handle<Name>::cast(function_name);
-    if (CheckMethodName(isolate, obj, name, fun_,
+    if (CheckMethodName(isolate_, obj, name, fun_,
                         LookupIterator::PROTOTYPE_CHAIN_SKIP_INTERCEPTOR))
       return name;
   }
 
-  HandleScope outer_scope(isolate);
+  HandleScope outer_scope(isolate_);
   Handle<Object> result;
-  for (PrototypeIterator iter(isolate, obj,
+  for (PrototypeIterator iter(isolate_, obj,
                               PrototypeIterator::START_AT_RECEIVER);
        !iter.IsAtEnd(); iter.Advance()) {
     Handle<Object> current = PrototypeIterator::GetCurrent(iter);
@@ -217,26 +230,26 @@ Handle<Object> CallSite::GetMethodName(Isolate* isolate) {
     if (current_obj->IsAccessCheckNeeded()) break;
     Handle<FixedArray> keys = JSObject::GetEnumPropertyKeys(current_obj, false);
     for (int i = 0; i < keys->length(); i++) {
-      HandleScope inner_scope(isolate);
+      HandleScope inner_scope(isolate_);
       if (!keys->get(i)->IsName()) continue;
-      Handle<Name> name_key(Name::cast(keys->get(i)), isolate);
-      if (!CheckMethodName(isolate, current_obj, name_key, fun_,
+      Handle<Name> name_key(Name::cast(keys->get(i)), isolate_);
+      if (!CheckMethodName(isolate_, current_obj, name_key, fun_,
                            LookupIterator::OWN_SKIP_INTERCEPTOR))
         continue;
       // Return null in case of duplicates to avoid confusion.
-      if (!result.is_null()) return isolate->factory()->null_value();
+      if (!result.is_null()) return isolate_->factory()->null_value();
       result = inner_scope.CloseAndEscape(name_key);
     }
   }
 
   if (!result.is_null()) return outer_scope.CloseAndEscape(result);
-  return isolate->factory()->null_value();
+  return isolate_->factory()->null_value();
 }
 
 
-int CallSite::GetLineNumber(Isolate* isolate) {
+int CallSite::GetLineNumber() {
   if (pos_ >= 0) {
-    Handle<Object> script_obj(fun_->shared()->script(), isolate);
+    Handle<Object> script_obj(fun_->shared()->script(), isolate_);
     if (script_obj->IsScript()) {
       Handle<Script> script = Handle<Script>::cast(script_obj);
       return Script::GetLineNumber(script, pos_) + 1;
@@ -246,9 +259,9 @@ int CallSite::GetLineNumber(Isolate* isolate) {
 }
 
 
-int CallSite::GetColumnNumber(Isolate* isolate) {
+int CallSite::GetColumnNumber() {
   if (pos_ >= 0) {
-    Handle<Object> script_obj(fun_->shared()->script(), isolate);
+    Handle<Object> script_obj(fun_->shared()->script(), isolate_);
     if (script_obj->IsScript()) {
       Handle<Script> script = Handle<Script>::cast(script_obj);
       return Script::GetColumnNumber(script, pos_) + 1;
@@ -258,32 +271,32 @@ int CallSite::GetColumnNumber(Isolate* isolate) {
 }
 
 
-bool CallSite::IsNative(Isolate* isolate) {
-  Handle<Object> script(fun_->shared()->script(), isolate);
+bool CallSite::IsNative() {
+  Handle<Object> script(fun_->shared()->script(), isolate_);
   return script->IsScript() &&
          Handle<Script>::cast(script)->type()->value() == Script::TYPE_NATIVE;
 }
 
 
-bool CallSite::IsToplevel(Isolate* isolate) {
+bool CallSite::IsToplevel() {
   return receiver_->IsJSGlobalProxy() || receiver_->IsNull() ||
          receiver_->IsUndefined();
 }
 
 
-bool CallSite::IsEval(Isolate* isolate) {
-  Handle<Object> script(fun_->shared()->script(), isolate);
+bool CallSite::IsEval() {
+  Handle<Object> script(fun_->shared()->script(), isolate_);
   return script->IsScript() &&
          Handle<Script>::cast(script)->compilation_type() ==
              Script::COMPILATION_TYPE_EVAL;
 }
 
 
-bool CallSite::IsConstructor(Isolate* isolate) {
+bool CallSite::IsConstructor() {
   if (!receiver_->IsJSObject()) return false;
   Handle<Object> constructor =
       JSReceiver::GetDataProperty(Handle<JSObject>::cast(receiver_),
-                                  isolate->factory()->constructor_string());
+                                  isolate_->factory()->constructor_string());
   return constructor.is_identical_to(fun_);
 }
 
diff --git a/src/messages.h b/src/messages.h
index 5d56ceb1c8..14f1dcf3ee 100644
--- a/src/messages.h
+++ b/src/messages.h
@@ -47,23 +47,23 @@ class MessageLocation {
 
 class CallSite {
  public:
-  CallSite(Handle<Object> receiver, Handle<JSFunction> fun, int pos)
-      : receiver_(receiver), fun_(fun), pos_(pos) {}
+  CallSite(Isolate* isolate, Handle<JSObject> call_site_obj);
 
-  Handle<Object> GetFileName(Isolate* isolate);
-  Handle<Object> GetFunctionName(Isolate* isolate);
-  Handle<Object> GetScriptNameOrSourceUrl(Isolate* isolate);
-  Handle<Object> GetMethodName(Isolate* isolate);
+  Handle<Object> GetFileName();
+  Handle<Object> GetFunctionName();
+  Handle<Object> GetScriptNameOrSourceUrl();
+  Handle<Object> GetMethodName();
   // Return 1-based line number, including line offset.
-  int GetLineNumber(Isolate* isolate);
+  int GetLineNumber();
   // Return 1-based column number, including column offset if first line.
-  int GetColumnNumber(Isolate* isolate);
-  bool IsNative(Isolate* isolate);
-  bool IsToplevel(Isolate* isolate);
-  bool IsEval(Isolate* isolate);
-  bool IsConstructor(Isolate* isolate);
+  int GetColumnNumber();
+  bool IsNative();
+  bool IsToplevel();
+  bool IsEval();
+  bool IsConstructor();
 
  private:
+  Isolate* isolate_;
   Handle<Object> receiver_;
   Handle<JSFunction> fun_;
   int pos_;
diff --git a/src/messages.js b/src/messages.js
index 32766a89fe..f0d241aebc 100644
--- a/src/messages.js
+++ b/src/messages.js
@@ -5,8 +5,6 @@
 // -------------------------------------------------------------------
 
 var $errorToString;
-var $internalErrorSymbol;
-var $stackTraceSymbol;
 var MakeError;
 var MakeEvalError;
 var MakeRangeError;
@@ -26,15 +24,26 @@ var ArrayJoin;
 var Bool16x8ToString;
 var Bool32x4ToString;
 var Bool8x16ToString;
+var callSiteReceiverSymbol =
+    utils.GetPrivateSymbol("call_site_receiver_symbol");
+var callSiteFunctionSymbol =
+    utils.GetPrivateSymbol("call_site_function_symbol");
+var callSitePositionSymbol =
+    utils.GetPrivateSymbol("call_site_position_symbol");
+var callSiteStrictSymbol = utils.GetPrivateSymbol("call_site_strict_symbol");
 var Float32x4ToString;
+var formattedStackTraceSymbol =
+    utils.GetPrivateSymbol("formatted_stack_trace_symbol");
 var FunctionSourceString
 var GlobalObject = global.Object;
 var Int16x8ToString;
 var Int32x4ToString;
 var Int8x16ToString;
 var InternalArray = utils.InternalArray;
+var internalErrorSymbol = utils.GetPrivateSymbol("internal_error_symbol");
 var ObjectDefineProperty;
 var ObjectToString;
+var stackTraceSymbol = utils.GetPrivateSymbol("stack_trace_symbol");
 var StringCharAt;
 var StringIndexOf;
 var StringSubstring;
@@ -173,7 +182,7 @@ function ToDetailString(obj) {
 
 function MakeGenericError(constructor, type, arg0, arg1, arg2) {
   var error = new constructor(FormatMessage(type, arg0, arg1, arg2));
-  error[$internalErrorSymbol] = true;
+  error[internalErrorSymbol] = true;
   return error;
 }
 
@@ -574,112 +583,77 @@ function GetStackTraceLine(recv, fun, pos, isGlobal) {
 // ----------------------------------------------------------------------------
 // Error implementation
 
-var CallSiteReceiverKey = NEW_PRIVATE("CallSite#receiver");
-var CallSiteFunctionKey = NEW_PRIVATE("CallSite#function");
-var CallSitePositionKey = NEW_PRIVATE("CallSite#position");
-var CallSiteStrictModeKey = NEW_PRIVATE("CallSite#strict_mode");
-
 function CallSite(receiver, fun, pos, strict_mode) {
-  SET_PRIVATE(this, CallSiteReceiverKey, receiver);
-  SET_PRIVATE(this, CallSiteFunctionKey, fun);
-  SET_PRIVATE(this, CallSitePositionKey, pos);
-  SET_PRIVATE(this, CallSiteStrictModeKey, strict_mode);
+  SET_PRIVATE(this, callSiteReceiverSymbol, receiver);
+  SET_PRIVATE(this, callSiteFunctionSymbol, fun);
+  SET_PRIVATE(this, callSitePositionSymbol, pos);
+  SET_PRIVATE(this, callSiteStrictSymbol, strict_mode);
 }
 
 function CallSiteGetThis() {
-  return GET_PRIVATE(this, CallSiteStrictModeKey)
-      ? UNDEFINED : GET_PRIVATE(this, CallSiteReceiverKey);
+  return GET_PRIVATE(this, callSiteStrictSymbol)
+      ? UNDEFINED : GET_PRIVATE(this, callSiteReceiverSymbol);
 }
 
 function CallSiteGetFunction() {
-  return GET_PRIVATE(this, CallSiteStrictModeKey)
-      ? UNDEFINED : GET_PRIVATE(this, CallSiteFunctionKey);
+  return GET_PRIVATE(this, callSiteStrictSymbol)
+      ? UNDEFINED : GET_PRIVATE(this, callSiteFunctionSymbol);
 }
 
 function CallSiteGetPosition() {
-  return GET_PRIVATE(this, CallSitePositionKey);
+  return GET_PRIVATE(this, callSitePositionSymbol);
 }
 
 function CallSiteGetTypeName() {
-  return GetTypeName(GET_PRIVATE(this, CallSiteReceiverKey), false);
+  return GetTypeName(GET_PRIVATE(this, callSiteReceiverSymbol), false);
 }
 
 function CallSiteIsToplevel() {
-  var receiver = GET_PRIVATE(this, CallSiteReceiverKey);
-  var fun = GET_PRIVATE(this, CallSiteFunctionKey);
-  var pos = GET_PRIVATE(this, CallSitePositionKey);
-  return %CallSiteIsToplevelRT(receiver, fun, pos);
+  return %CallSiteIsToplevelRT(this);
 }
 
 function CallSiteIsEval() {
-  var receiver = GET_PRIVATE(this, CallSiteReceiverKey);
-  var fun = GET_PRIVATE(this, CallSiteFunctionKey);
-  var pos = GET_PRIVATE(this, CallSitePositionKey);
-  return %CallSiteIsEvalRT(receiver, fun, pos);
+  return %CallSiteIsEvalRT(this);
 }
 
 function CallSiteGetEvalOrigin() {
-  var script = %FunctionGetScript(GET_PRIVATE(this, CallSiteFunctionKey));
+  var script = %FunctionGetScript(GET_PRIVATE(this, callSiteFunctionSymbol));
   return FormatEvalOrigin(script);
 }
 
 function CallSiteGetScriptNameOrSourceURL() {
-  var receiver = GET_PRIVATE(this, CallSiteReceiverKey);
-  var fun = GET_PRIVATE(this, CallSiteFunctionKey);
-  var pos = GET_PRIVATE(this, CallSitePositionKey);
-  return %CallSiteGetScriptNameOrSourceUrlRT(receiver, fun, pos);
+  return %CallSiteGetScriptNameOrSourceUrlRT(this);
 }
 
 function CallSiteGetFunctionName() {
   // See if the function knows its own name
-  var receiver = GET_PRIVATE(this, CallSiteReceiverKey);
-  var fun = GET_PRIVATE(this, CallSiteFunctionKey);
-  var pos = GET_PRIVATE(this, CallSitePositionKey);
-  return %CallSiteGetFunctionNameRT(receiver, fun, pos);
+  return %CallSiteGetFunctionNameRT(this);
 }
 
 function CallSiteGetMethodName() {
   // See if we can find a unique property on the receiver that holds
   // this function.
-  var receiver = GET_PRIVATE(this, CallSiteReceiverKey);
-  var fun = GET_PRIVATE(this, CallSiteFunctionKey);
-  var pos = GET_PRIVATE(this, CallSitePositionKey);
-  return %CallSiteGetMethodNameRT(receiver, fun, pos);
+  return %CallSiteGetMethodNameRT(this);
 }
 
 function CallSiteGetFileName() {
-  var receiver = GET_PRIVATE(this, CallSiteReceiverKey);
-  var fun = GET_PRIVATE(this, CallSiteFunctionKey);
-  var pos = GET_PRIVATE(this, CallSitePositionKey);
-  return %CallSiteGetFileNameRT(receiver, fun, pos);
+  return %CallSiteGetFileNameRT(this);
 }
 
 function CallSiteGetLineNumber() {
-  var receiver = GET_PRIVATE(this, CallSiteReceiverKey);
-  var fun = GET_PRIVATE(this, CallSiteFunctionKey);
-  var pos = GET_PRIVATE(this, CallSitePositionKey);
-  return %CallSiteGetLineNumberRT(receiver, fun, pos);
+  return %CallSiteGetLineNumberRT(this);
 }
 
 function CallSiteGetColumnNumber() {
-  var receiver = GET_PRIVATE(this, CallSiteReceiverKey);
-  var fun = GET_PRIVATE(this, CallSiteFunctionKey);
-  var pos = GET_PRIVATE(this, CallSitePositionKey);
-  return %CallSiteGetColumnNumberRT(receiver, fun, pos);
+  return %CallSiteGetColumnNumberRT(this);
 }
 
 function CallSiteIsNative() {
-  var receiver = GET_PRIVATE(this, CallSiteReceiverKey);
-  var fun = GET_PRIVATE(this, CallSiteFunctionKey);
-  var pos = GET_PRIVATE(this, CallSitePositionKey);
-  return %CallSiteIsNativeRT(receiver, fun, pos);
+  return %CallSiteIsNativeRT(this);
 }
 
 function CallSiteIsConstructor() {
-  var receiver = GET_PRIVATE(this, CallSiteReceiverKey);
-  var fun = GET_PRIVATE(this, CallSiteFunctionKey);
-  var pos = GET_PRIVATE(this, CallSitePositionKey);
-  return %CallSiteIsConstructorRT(receiver, fun, pos);
+  return %CallSiteIsConstructorRT(this);
 }
 
 function CallSiteToString() {
@@ -718,7 +692,7 @@ function CallSiteToString() {
   var isConstructor = this.isConstructor();
   var isMethodCall = !(this.isToplevel() || isConstructor);
   if (isMethodCall) {
-    var typeName = GetTypeName(GET_PRIVATE(this, CallSiteReceiverKey), true);
+    var typeName = GetTypeName(GET_PRIVATE(this, callSiteReceiverSymbol), true);
     var methodName = this.getMethodName();
     if (functionName) {
       if (typeName &&
@@ -894,8 +868,6 @@ function GetTypeName(receiver, requireConstructor) {
   return constructorName;
 }
 
-var formatted_stack_trace_symbol = NEW_PRIVATE("formatted stack trace");
-
 
 // Format the stack trace if not yet done, and return it.
 // Cache the formatted stack trace on the holder.
@@ -904,10 +876,10 @@ var StackTraceGetter = function() {
   var holder = this;
   while (holder) {
     var formatted_stack_trace =
-      GET_PRIVATE(holder, formatted_stack_trace_symbol);
+      GET_PRIVATE(holder, formattedStackTraceSymbol);
     if (IS_UNDEFINED(formatted_stack_trace)) {
       // No formatted stack trace available.
-      var stack_trace = GET_PRIVATE(holder, $stackTraceSymbol);
+      var stack_trace = GET_PRIVATE(holder, stackTraceSymbol);
       if (IS_UNDEFINED(stack_trace)) {
         // Neither formatted nor structured stack trace available.
         // Look further up the prototype chain.
@@ -915,8 +887,8 @@ var StackTraceGetter = function() {
         continue;
       }
       formatted_stack_trace = FormatStackTrace(holder, stack_trace);
-      SET_PRIVATE(holder, $stackTraceSymbol, UNDEFINED);
-      SET_PRIVATE(holder, formatted_stack_trace_symbol, formatted_stack_trace);
+      SET_PRIVATE(holder, stackTraceSymbol, UNDEFINED);
+      SET_PRIVATE(holder, formattedStackTraceSymbol, formatted_stack_trace);
     }
     return formatted_stack_trace;
   }
@@ -927,9 +899,9 @@ var StackTraceGetter = function() {
 // If the receiver equals the holder, set the formatted stack trace that the
 // getter returns.
 var StackTraceSetter = function(v) {
-  if (HAS_PRIVATE(this, $stackTraceSymbol)) {
-    SET_PRIVATE(this, $stackTraceSymbol, UNDEFINED);
-    SET_PRIVATE(this, formatted_stack_trace_symbol, v);
+  if (HAS_PRIVATE(this, stackTraceSymbol)) {
+    SET_PRIVATE(this, stackTraceSymbol, UNDEFINED);
+    SET_PRIVATE(this, formattedStackTraceSymbol, v);
   }
 };
 
diff --git a/src/objects.cc b/src/objects.cc
index 841af8509a..552d4f5516 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -139,7 +139,7 @@ bool Object::IsPromise(Handle<Object> object) {
   auto isolate = js_object->GetIsolate();
   // TODO(dcarney): this should just be read from the symbol registry so as not
   // to be context dependent.
-  auto key = isolate->promise_status();
+  auto key = isolate->factory()->promise_status_symbol();
   // Shouldn't be possible to throw here.
   return JSObject::HasRealNamedProperty(js_object, key).FromJust();
 }
diff --git a/src/prologue.js b/src/prologue.js
index 4906d41f3d..56f9ed5b38 100644
--- a/src/prologue.js
+++ b/src/prologue.js
@@ -156,6 +156,13 @@ function SetUpLockedPrototype(
   %ToFastProperties(prototype);
 }
 
+
+var private_symbols = %ExportPrivateSymbols({});
+
+function GetPrivateSymbol(name) {
+  return private_symbols[name];
+}
+
 // -----------------------------------------------------------------------
 // To be called by bootstrapper
 
@@ -236,6 +243,7 @@ function PostExperimentals(utils) {
   %ImportExperimentalToRuntime(runtime_container);
 
   exports_container = UNDEFINED;
+  private_symbols = UNDEFINED;
 
   utils.PostExperimentals = UNDEFINED;
   utils.PostDebug = UNDEFINED;
@@ -250,6 +258,7 @@ function PostDebug(utils) {
   }
 
   exports_container = UNDEFINED;
+  private_symbols = UNDEFINED;
 
   utils.PostDebug = UNDEFINED;
   utils.PostExperimentals = UNDEFINED;
@@ -259,13 +268,14 @@ function PostDebug(utils) {
 
 // -----------------------------------------------------------------------
 
-%OptimizeObjectForAddingMultipleProperties(utils, 14);
+%OptimizeObjectForAddingMultipleProperties(utils, 15);
 
 utils.Import = Import;
 utils.ImportNow = ImportNow;
 utils.Export = Export;
 utils.ExportToRuntime = ExportToRuntime;
 utils.ImportFromExperimental = ImportFromExperimental;
+utils.GetPrivateSymbol = GetPrivateSymbol;
 utils.SetFunctionName = SetFunctionName;
 utils.InstallConstants = InstallConstants;
 utils.InstallFunctions = InstallFunctions;
diff --git a/src/promise.js b/src/promise.js
index 0233dbebe4..863790fb36 100644
--- a/src/promise.js
+++ b/src/promise.js
@@ -2,10 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-var $promiseHasUserDefinedRejectHandler;
-var $promiseStatus;
-var $promiseValue;
-
 (function(global, utils) {
 
 "use strict";
@@ -16,20 +12,22 @@ var $promiseValue;
 // Imports
 
 var InternalArray = utils.InternalArray;
+var promiseHasHandlerSymbol =
+    utils.GetPrivateSymbol("promise_has_handler_symbol");
+var promiseOnRejectSymbol = utils.GetPrivateSymbol("promise_on_reject_symbol");
+var promiseOnResolveSymbol =
+    utils.GetPrivateSymbol("promise_on_resolve_symbol");
+var promiseRawSymbol = utils.GetPrivateSymbol("promise_raw_symbol");
+var promiseStatusSymbol = utils.GetPrivateSymbol("promise_status_symbol");
+var promiseValueSymbol = utils.GetPrivateSymbol("promise_value_symbol");
 
 // -------------------------------------------------------------------
 
 // Status values: 0 = pending, +1 = resolved, -1 = rejected
-var promiseStatus = GLOBAL_PRIVATE("Promise#status");
-var promiseValue = GLOBAL_PRIVATE("Promise#value");
-var promiseOnResolve = GLOBAL_PRIVATE("Promise#onResolve");
-var promiseOnReject = GLOBAL_PRIVATE("Promise#onReject");
-var promiseRaw = GLOBAL_PRIVATE("Promise#raw");
-var promiseHasHandler = %PromiseHasHandlerSymbol();
 var lastMicrotaskId = 0;
 
 var GlobalPromise = function Promise(resolver) {
-  if (resolver === promiseRaw) return;
+  if (resolver === promiseRawSymbol) return;
   if (!%_IsConstructCall()) throw MakeTypeError(kNotAPromise, this);
   if (!IS_SPEC_FUNCTION(resolver))
     throw MakeTypeError(kResolverNotAFunction, resolver);
@@ -48,10 +46,10 @@ var GlobalPromise = function Promise(resolver) {
 // Core functionality.
 
 function PromiseSet(promise, status, value, onResolve, onReject) {
-  SET_PRIVATE(promise, promiseStatus, status);
-  SET_PRIVATE(promise, promiseValue, value);
-  SET_PRIVATE(promise, promiseOnResolve, onResolve);
-  SET_PRIVATE(promise, promiseOnReject, onReject);
+  SET_PRIVATE(promise, promiseStatusSymbol, status);
+  SET_PRIVATE(promise, promiseValueSymbol, value);
+  SET_PRIVATE(promise, promiseOnResolveSymbol, onResolve);
+  SET_PRIVATE(promise, promiseOnRejectSymbol, onReject);
   if (DEBUG_IS_ACTIVE) {
     %DebugPromiseEvent({ promise: promise, status: status, value: value });
   }
@@ -59,7 +57,7 @@ function PromiseSet(promise, status, value, onResolve, onReject) {
 }
 
 function PromiseCreateAndSet(status, value) {
-  var promise = new GlobalPromise(promiseRaw);
+  var promise = new GlobalPromise(promiseRawSymbol);
   // If debug is active, notify about the newly created promise first.
   if (DEBUG_IS_ACTIVE) PromiseSet(promise, 0, UNDEFINED);
   return PromiseSet(promise, status, value);
@@ -71,7 +69,7 @@ function PromiseInit(promise) {
 }
 
 function PromiseDone(promise, status, value, promiseQueue) {
-  if (GET_PRIVATE(promise, promiseStatus) === 0) {
+  if (GET_PRIVATE(promise, promiseStatusSymbol) === 0) {
     var tasks = GET_PRIVATE(promise, promiseQueue);
     if (tasks.length) PromiseEnqueue(value, tasks, status);
     PromiseSet(promise, status, value);
@@ -148,7 +146,7 @@ function PromiseNopResolver() {}
 // For bootstrapper.
 
 function IsPromise(x) {
-  return IS_SPEC_OBJECT(x) && HAS_DEFINED_PRIVATE(x, promiseStatus);
+  return IS_SPEC_OBJECT(x) && HAS_DEFINED_PRIVATE(x, promiseStatusSymbol);
 }
 
 function PromiseCreate() {
@@ -156,19 +154,20 @@ function PromiseCreate() {
 }
 
 function PromiseResolve(promise, x) {
-  PromiseDone(promise, +1, x, promiseOnResolve)
+  PromiseDone(promise, +1, x, promiseOnResolveSymbol)
 }
 
 function PromiseReject(promise, r) {
   // Check promise status to confirm that this reject has an effect.
   // Call runtime for callbacks to the debugger or for unhandled reject.
-  if (GET_PRIVATE(promise, promiseStatus) == 0) {
+  if (GET_PRIVATE(promise, promiseStatusSymbol) == 0) {
     var debug_is_active = DEBUG_IS_ACTIVE;
-    if (debug_is_active || !HAS_DEFINED_PRIVATE(promise, promiseHasHandler)) {
+    if (debug_is_active ||
+        !HAS_DEFINED_PRIVATE(promise, promiseHasHandlerSymbol)) {
       %PromiseRejectEvent(promise, r, debug_is_active);
     }
   }
-  PromiseDone(promise, -1, r, promiseOnReject)
+  PromiseDone(promise, -1, r, promiseOnRejectSymbol)
 }
 
 // Convenience.
@@ -176,7 +175,7 @@ function PromiseReject(promise, r) {
 function PromiseDeferred() {
   if (this === GlobalPromise) {
     // Optimized case, avoid extra closure.
-    var promise = PromiseInit(new GlobalPromise(promiseRaw));
+    var promise = PromiseInit(new GlobalPromise(promiseRawSymbol));
     return {
       promise: promise,
       resolve: function(x) { PromiseResolve(promise, x) },
@@ -221,31 +220,31 @@ function PromiseChain(onResolve, onReject) {  // a.k.a. flatMap
   onResolve = IS_UNDEFINED(onResolve) ? PromiseIdResolveHandler : onResolve;
   onReject = IS_UNDEFINED(onReject) ? PromiseIdRejectHandler : onReject;
   var deferred = %_CallFunction(this.constructor, PromiseDeferred);
-  switch (GET_PRIVATE(this, promiseStatus)) {
+  switch (GET_PRIVATE(this, promiseStatusSymbol)) {
     case UNDEFINED:
       throw MakeTypeError(kNotAPromise, this);
     case 0:  // Pending
-      GET_PRIVATE(this, promiseOnResolve).push(onResolve, deferred);
-      GET_PRIVATE(this, promiseOnReject).push(onReject, deferred);
+      GET_PRIVATE(this, promiseOnResolveSymbol).push(onResolve, deferred);
+      GET_PRIVATE(this, promiseOnRejectSymbol).push(onReject, deferred);
       break;
     case +1:  // Resolved
-      PromiseEnqueue(GET_PRIVATE(this, promiseValue),
+      PromiseEnqueue(GET_PRIVATE(this, promiseValueSymbol),
                      [onResolve, deferred],
                      +1);
       break;
     case -1:  // Rejected
-      if (!HAS_DEFINED_PRIVATE(this, promiseHasHandler)) {
+      if (!HAS_DEFINED_PRIVATE(this, promiseHasHandlerSymbol)) {
         // Promise has already been rejected, but had no handler.
         // Revoke previously triggered reject event.
         %PromiseRevokeReject(this);
       }
-      PromiseEnqueue(GET_PRIVATE(this, promiseValue),
+      PromiseEnqueue(GET_PRIVATE(this, promiseValueSymbol),
                      [onReject, deferred],
                      -1);
       break;
   }
   // Mark this promise as having handler.
-  SET_PRIVATE(this, promiseHasHandler, true);
+  SET_PRIVATE(this, promiseHasHandlerSymbol, true);
   if (DEBUG_IS_ACTIVE) {
     %DebugPromiseEvent({ promise: deferred.promise, parentPromise: this });
   }
@@ -340,7 +339,7 @@ function PromiseRace(iterable) {
 // Utility for debugger
 
 function PromiseHasUserDefinedRejectHandlerRecursive(promise) {
-  var queue = GET_PRIVATE(promise, promiseOnReject);
+  var queue = GET_PRIVATE(promise, promiseOnRejectSymbol);
   if (IS_UNDEFINED(queue)) return false;
   for (var i = 0; i < queue.length; i += 2) {
     if (queue[i] != PromiseIdRejectHandler) return true;
@@ -380,12 +379,7 @@ utils.InstallFunctions(GlobalPromise.prototype, DONT_ENUM, [
   "catch", PromiseCatch
 ]);
 
-$promiseStatus = promiseStatus;
-$promiseValue = promiseValue;
-
 utils.ExportToRuntime(function(to) {
-  to.promiseStatus = promiseStatus;
-  to.promiseValue = promiseValue;
   to.PromiseCreate = PromiseCreate;
   to.PromiseResolve = PromiseResolve;
   to.PromiseReject = PromiseReject;
diff --git a/src/runtime/runtime-debug.cc b/src/runtime/runtime-debug.cc
index 1cd524f17c..41372e4694 100644
--- a/src/runtime/runtime-debug.cc
+++ b/src/runtime/runtime-debug.cc
@@ -221,7 +221,7 @@ MaybeHandle<JSArray> Runtime::GetInternalProperties(Isolate* isolate,
     Handle<JSObject> promise = Handle<JSObject>::cast(object);
 
     Handle<Object> status_obj =
-        DebugGetProperty(promise, isolate->promise_status());
+        DebugGetProperty(promise, isolate->factory()->promise_status_symbol());
     RUNTIME_ASSERT_HANDLIFIED(status_obj->IsSmi(), JSArray);
     const char* status = "rejected";
     int status_val = Handle<Smi>::cast(status_obj)->value();
@@ -244,7 +244,7 @@ MaybeHandle<JSArray> Runtime::GetInternalProperties(Isolate* isolate,
     result->set(1, *status_str);
 
     Handle<Object> value_obj =
-        DebugGetProperty(promise, isolate->promise_value());
+        DebugGetProperty(promise, isolate->factory()->promise_value_symbol());
     Handle<String> promise_value =
         factory->NewStringFromAsciiChecked("[[PromiseValue]]");
     result->set(2, *promise_value);
diff --git a/src/runtime/runtime-internal.cc b/src/runtime/runtime-internal.cc
index 01e3e913af..0e098fd1f0 100644
--- a/src/runtime/runtime-internal.cc
+++ b/src/runtime/runtime-internal.cc
@@ -24,6 +24,19 @@ RUNTIME_FUNCTION(Runtime_CheckIsBootstrapping) {
 }
 
 
+RUNTIME_FUNCTION(Runtime_ExportPrivateSymbols) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSObject, container, 0);
+  RUNTIME_ASSERT(isolate->bootstrapper()->IsActive());
+  JSObject::NormalizeProperties(container, KEEP_INOBJECT_PROPERTIES, 10,
+                                "ExportPrivateSymbols");
+  Bootstrapper::ExportPrivateSymbols(isolate, container);
+  JSObject::MigrateSlowToFast(container, 0, "ExportPrivateSymbols");
+  return *container;
+}
+
+
 RUNTIME_FUNCTION(Runtime_ImportToRuntime) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 1);
@@ -172,12 +185,6 @@ RUNTIME_FUNCTION(Runtime_PromiseRevokeReject) {
 }
 
 
-RUNTIME_FUNCTION(Runtime_PromiseHasHandlerSymbol) {
-  DCHECK(args.length() == 0);
-  return isolate->heap()->promise_has_handler_symbol();
-}
-
-
 RUNTIME_FUNCTION(Runtime_StackGuard) {
   SealHandleScope shs(isolate);
   DCHECK(args.length() == 0);
@@ -311,16 +318,14 @@ RUNTIME_FUNCTION(Runtime_FormatMessageString) {
 }
 
 
-#define CALLSITE_GET(NAME, RETURN)                   \
-  RUNTIME_FUNCTION(Runtime_CallSite##NAME##RT) {     \
-    HandleScope scope(isolate);                      \
-    DCHECK(args.length() == 3);                      \
-    CONVERT_ARG_HANDLE_CHECKED(Object, receiver, 0); \
-    CONVERT_ARG_HANDLE_CHECKED(JSFunction, fun, 1);  \
-    CONVERT_INT32_ARG_CHECKED(pos, 2);               \
-    Handle<String> result;                           \
-    CallSite call_site(receiver, fun, pos);          \
-    return RETURN(call_site.NAME(isolate), isolate); \
+#define CALLSITE_GET(NAME, RETURN)                          \
+  RUNTIME_FUNCTION(Runtime_CallSite##NAME##RT) {            \
+    HandleScope scope(isolate);                             \
+    DCHECK(args.length() == 1);                             \
+    CONVERT_ARG_HANDLE_CHECKED(JSObject, call_site_obj, 0); \
+    Handle<String> result;                                  \
+    CallSite call_site(isolate, call_site_obj);             \
+    return RETURN(call_site.NAME(), isolate);               \
   }
 
 static inline Object* ReturnDereferencedHandle(Handle<Object> obj,
diff --git a/src/runtime/runtime-symbol.cc b/src/runtime/runtime-symbol.cc
index 8f99a37c42..03bd76ce27 100644
--- a/src/runtime/runtime-symbol.cc
+++ b/src/runtime/runtime-symbol.cc
@@ -30,27 +30,6 @@ RUNTIME_FUNCTION(Runtime_CreatePrivateSymbol) {
 }
 
 
-RUNTIME_FUNCTION(Runtime_CreateGlobalPrivateSymbol) {
-  HandleScope scope(isolate);
-  DCHECK(args.length() == 1);
-  CONVERT_ARG_HANDLE_CHECKED(String, name, 0);
-  Handle<JSObject> registry = isolate->GetSymbolRegistry();
-  Handle<String> part = isolate->factory()->private_intern_string();
-  Handle<Object> privates;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, privates,
-                                     Object::GetProperty(registry, part));
-  Handle<Object> symbol;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, symbol,
-                                     Object::GetProperty(privates, name));
-  if (!symbol->IsSymbol()) {
-    DCHECK(symbol->IsUndefined());
-    symbol = isolate->factory()->NewPrivateSymbol(name);
-    JSObject::AddProperty(Handle<JSObject>::cast(privates), name, symbol, NONE);
-  }
-  return *symbol;
-}
-
-
 RUNTIME_FUNCTION(Runtime_SymbolDescription) {
   SealHandleScope shs(isolate);
   DCHECK(args.length() == 1);
diff --git a/src/runtime/runtime.h b/src/runtime/runtime.h
index 112d947dbc..7107bdef37 100644
--- a/src/runtime/runtime.h
+++ b/src/runtime/runtime.h
@@ -302,6 +302,7 @@ namespace internal {
 
 #define FOR_EACH_INTRINSIC_INTERNAL(F)        \
   F(CheckIsBootstrapping, 0, 1)               \
+  F(ExportPrivateSymbols, 1, 1)               \
   F(ImportToRuntime, 1, 1)                    \
   F(ImportExperimentalToRuntime, 1, 1)        \
   F(InstallJSBuiltins, 1, 1)                  \
@@ -317,7 +318,6 @@ namespace internal {
   F(ThrowStrongModeImplicitConversion, 0, 1)  \
   F(PromiseRejectEvent, 3, 1)                 \
   F(PromiseRevokeReject, 1, 1)                \
-  F(PromiseHasHandlerSymbol, 0, 1)            \
   F(StackGuard, 0, 1)                         \
   F(Interrupt, 0, 1)                          \
   F(AllocateInNewSpace, 1, 1)                 \
@@ -328,16 +328,16 @@ namespace internal {
   F(MessageGetScript, 1, 1)                   \
   F(ErrorToStringRT, 1, 1)                    \
   F(FormatMessageString, 4, 1)                \
-  F(CallSiteGetFileNameRT, 3, 1)              \
-  F(CallSiteGetFunctionNameRT, 3, 1)          \
-  F(CallSiteGetScriptNameOrSourceUrlRT, 3, 1) \
-  F(CallSiteGetMethodNameRT, 3, 1)            \
-  F(CallSiteGetLineNumberRT, 3, 1)            \
-  F(CallSiteGetColumnNumberRT, 3, 1)          \
-  F(CallSiteIsNativeRT, 3, 1)                 \
-  F(CallSiteIsToplevelRT, 3, 1)               \
-  F(CallSiteIsEvalRT, 3, 1)                   \
-  F(CallSiteIsConstructorRT, 3, 1)            \
+  F(CallSiteGetFileNameRT, 1, 1)              \
+  F(CallSiteGetFunctionNameRT, 1, 1)          \
+  F(CallSiteGetScriptNameOrSourceUrlRT, 1, 1) \
+  F(CallSiteGetMethodNameRT, 1, 1)            \
+  F(CallSiteGetLineNumberRT, 1, 1)            \
+  F(CallSiteGetColumnNumberRT, 1, 1)          \
+  F(CallSiteIsNativeRT, 1, 1)                 \
+  F(CallSiteIsToplevelRT, 1, 1)               \
+  F(CallSiteIsEvalRT, 1, 1)                   \
+  F(CallSiteIsConstructorRT, 1, 1)            \
   F(IS_VAR, 1, 1)                             \
   F(IncrementStatsCounter, 1, 1)              \
   F(Likely, 1, 1)                             \
@@ -776,7 +776,6 @@ namespace internal {
 #define FOR_EACH_INTRINSIC_SYMBOL(F) \
   F(CreateSymbol, 1, 1)              \
   F(CreatePrivateSymbol, 1, 1)       \
-  F(CreateGlobalPrivateSymbol, 1, 1) \
   F(SymbolDescription, 1, 1)         \
   F(SymbolRegistry, 0, 1)            \
   F(SymbolIsPrivate, 1, 1)
diff --git a/src/string-iterator.js b/src/string-iterator.js
index bb392ef10e..4e51a12a2e 100644
--- a/src/string-iterator.js
+++ b/src/string-iterator.js
@@ -11,9 +11,12 @@
 // -------------------------------------------------------------------
 // Imports
 
-var GlobalString = global.String;
-
 var ArrayIteratorCreateResultObject;
+var GlobalString = global.String;
+var stringIteratorIteratedStringSymbol =
+    utils.GetPrivateSymbol("string_iterator_iterated_string_symbol");
+var stringIteratorNextIndexSymbol =
+    utils.GetPrivateSymbol("string_iterator_next_index_symbol");
 
 utils.Import(function(from) {
   ArrayIteratorCreateResultObject = from.ArrayIteratorCreateResultObject;
@@ -21,11 +24,6 @@ utils.Import(function(from) {
 
 // -------------------------------------------------------------------
 
-var stringIteratorIteratedStringSymbol =
-    GLOBAL_PRIVATE("StringIterator#iteratedString");
-var stringIteratorNextIndexSymbol = GLOBAL_PRIVATE("StringIterator#next");
-
-
 function StringIterator() {}