diff --git a/objectivec/GPBDictionary_PackagePrivate.h b/objectivec/GPBDictionary_PackagePrivate.h
new file mode 100644
index 0000000..7b921e8
--- /dev/null
+++ b/objectivec/GPBDictionary_PackagePrivate.h
@@ -0,0 +1,488 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#import <Foundation/Foundation.h>
+
+#import "GPBDictionary.h"
+
+@class GPBCodedInputStream;
+@class GPBCodedOutputStream;
+@class GPBExtensionRegistry;
+@class GPBFieldDescriptor;
+
+@protocol GPBDictionaryInternalsProtocol
+- (size_t)computeSerializedSizeAsField:(GPBFieldDescriptor *)field;
+- (void)writeToCodedOutputStream:(GPBCodedOutputStream *)outputStream
+                         asField:(GPBFieldDescriptor *)field;
+- (void)setGPBGenericValue:(GPBGenericValue *)value
+     forGPBGenericValueKey:(GPBGenericValue *)key;
+- (void)enumerateForTextFormat:(void (^)(id keyObj, id valueObj))block;
+@end
+
+//%PDDM-DEFINE DICTIONARY_PRIV_INTERFACES_FOR_POD_KEY(KEY_NAME)
+//%DICTIONARY_POD_PRIV_INTERFACES_FOR_KEY(KEY_NAME)
+//%DICTIONARY_PRIVATE_INTERFACES(KEY_NAME, Object, Object)
+//%PDDM-DEFINE DICTIONARY_POD_PRIV_INTERFACES_FOR_KEY(KEY_NAME)
+//%DICTIONARY_PRIVATE_INTERFACES(KEY_NAME, UInt32, Basic)
+//%DICTIONARY_PRIVATE_INTERFACES(KEY_NAME, Int32, Basic)
+//%DICTIONARY_PRIVATE_INTERFACES(KEY_NAME, UInt64, Basic)
+//%DICTIONARY_PRIVATE_INTERFACES(KEY_NAME, Int64, Basic)
+//%DICTIONARY_PRIVATE_INTERFACES(KEY_NAME, Bool, Basic)
+//%DICTIONARY_PRIVATE_INTERFACES(KEY_NAME, Float, Basic)
+//%DICTIONARY_PRIVATE_INTERFACES(KEY_NAME, Double, Basic)
+//%DICTIONARY_PRIVATE_INTERFACES(KEY_NAME, Enum, Enum)
+
+//%PDDM-DEFINE DICTIONARY_PRIVATE_INTERFACES(KEY_NAME, VALUE_NAME, HELPER)
+//%@interface GPB##KEY_NAME##VALUE_NAME##Dictionary () <GPBDictionaryInternalsProtocol> {
+//% @package
+//%  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+//%}
+//%EXTRA_DICTIONARY_PRIVATE_INTERFACES_##HELPER()@end
+//%
+
+//%PDDM-DEFINE EXTRA_DICTIONARY_PRIVATE_INTERFACES_Basic()
+// Empty
+//%PDDM-DEFINE EXTRA_DICTIONARY_PRIVATE_INTERFACES_Object()
+//%- (BOOL)isInitialized;
+//%- (instancetype)deepCopyWithZone:(NSZone *)zone
+//%    __attribute__((ns_returns_retained));
+//%
+//%PDDM-DEFINE EXTRA_DICTIONARY_PRIVATE_INTERFACES_Enum()
+//%- (NSData *)serializedDataForUnknownValue:(int32_t)value
+//%                                   forKey:(GPBGenericValue *)key
+//%                              keyDataType:(GPBDataType)keyDataType;
+//%
+
+//%PDDM-EXPAND DICTIONARY_PRIV_INTERFACES_FOR_POD_KEY(UInt32)
+// This block of code is generated, do not edit it directly.
+
+@interface GPBUInt32UInt32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt32Int32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt32UInt64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt32Int64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt32BoolDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt32FloatDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt32DoubleDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt32EnumDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+- (NSData *)serializedDataForUnknownValue:(int32_t)value
+                                   forKey:(GPBGenericValue *)key
+                              keyDataType:(GPBDataType)keyDataType;
+@end
+
+@interface GPBUInt32ObjectDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+- (BOOL)isInitialized;
+- (instancetype)deepCopyWithZone:(NSZone *)zone
+    __attribute__((ns_returns_retained));
+@end
+
+//%PDDM-EXPAND DICTIONARY_PRIV_INTERFACES_FOR_POD_KEY(Int32)
+// This block of code is generated, do not edit it directly.
+
+@interface GPBInt32UInt32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt32Int32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt32UInt64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt32Int64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt32BoolDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt32FloatDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt32DoubleDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt32EnumDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+- (NSData *)serializedDataForUnknownValue:(int32_t)value
+                                   forKey:(GPBGenericValue *)key
+                              keyDataType:(GPBDataType)keyDataType;
+@end
+
+@interface GPBInt32ObjectDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+- (BOOL)isInitialized;
+- (instancetype)deepCopyWithZone:(NSZone *)zone
+    __attribute__((ns_returns_retained));
+@end
+
+//%PDDM-EXPAND DICTIONARY_PRIV_INTERFACES_FOR_POD_KEY(UInt64)
+// This block of code is generated, do not edit it directly.
+
+@interface GPBUInt64UInt32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt64Int32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt64UInt64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt64Int64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt64BoolDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt64FloatDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt64DoubleDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBUInt64EnumDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+- (NSData *)serializedDataForUnknownValue:(int32_t)value
+                                   forKey:(GPBGenericValue *)key
+                              keyDataType:(GPBDataType)keyDataType;
+@end
+
+@interface GPBUInt64ObjectDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+- (BOOL)isInitialized;
+- (instancetype)deepCopyWithZone:(NSZone *)zone
+    __attribute__((ns_returns_retained));
+@end
+
+//%PDDM-EXPAND DICTIONARY_PRIV_INTERFACES_FOR_POD_KEY(Int64)
+// This block of code is generated, do not edit it directly.
+
+@interface GPBInt64UInt32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt64Int32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt64UInt64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt64Int64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt64BoolDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt64FloatDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt64DoubleDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBInt64EnumDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+- (NSData *)serializedDataForUnknownValue:(int32_t)value
+                                   forKey:(GPBGenericValue *)key
+                              keyDataType:(GPBDataType)keyDataType;
+@end
+
+@interface GPBInt64ObjectDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+- (BOOL)isInitialized;
+- (instancetype)deepCopyWithZone:(NSZone *)zone
+    __attribute__((ns_returns_retained));
+@end
+
+//%PDDM-EXPAND DICTIONARY_PRIV_INTERFACES_FOR_POD_KEY(Bool)
+// This block of code is generated, do not edit it directly.
+
+@interface GPBBoolUInt32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBBoolInt32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBBoolUInt64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBBoolInt64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBBoolBoolDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBBoolFloatDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBBoolDoubleDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBBoolEnumDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+- (NSData *)serializedDataForUnknownValue:(int32_t)value
+                                   forKey:(GPBGenericValue *)key
+                              keyDataType:(GPBDataType)keyDataType;
+@end
+
+@interface GPBBoolObjectDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+- (BOOL)isInitialized;
+- (instancetype)deepCopyWithZone:(NSZone *)zone
+    __attribute__((ns_returns_retained));
+@end
+
+//%PDDM-EXPAND DICTIONARY_POD_PRIV_INTERFACES_FOR_KEY(String)
+// This block of code is generated, do not edit it directly.
+
+@interface GPBStringUInt32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBStringInt32Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBStringUInt64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBStringInt64Dictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBStringBoolDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBStringFloatDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBStringDoubleDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+@interface GPBStringEnumDictionary () <GPBDictionaryInternalsProtocol> {
+ @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+- (NSData *)serializedDataForUnknownValue:(int32_t)value
+                                   forKey:(GPBGenericValue *)key
+                              keyDataType:(GPBDataType)keyDataType;
+@end
+
+//%PDDM-EXPAND-END (6 expansions)
+
+#pragma mark - NSDictionary Subclass
+
+@interface GPBAutocreatedDictionary : NSMutableDictionary {
+  @package
+  GPB_UNSAFE_UNRETAINED GPBMessage *_autocreator;
+}
+@end
+
+#pragma mark - Helpers
+
+CF_EXTERN_C_BEGIN
+
+// Helper to compute size when an NSDictionary is used for the map instead
+// of a custom type.
+size_t GPBDictionaryComputeSizeInternalHelper(NSDictionary *dict,
+                                              GPBFieldDescriptor *field);
+
+// Helper to write out when an NSDictionary is used for the map instead
+// of a custom type.
+void GPBDictionaryWriteToStreamInternalHelper(
+    GPBCodedOutputStream *outputStream, NSDictionary *dict,
+    GPBFieldDescriptor *field);
+
+// Helper to check message initialization when an NSDictionary is used for
+// the map instead of a custom type.
+BOOL GPBDictionaryIsInitializedInternalHelper(NSDictionary *dict,
+                                              GPBFieldDescriptor *field);
+
+// Helper to read a map instead.
+void GPBDictionaryReadEntry(id mapDictionary, GPBCodedInputStream *stream,
+                            GPBExtensionRegistry *registry,
+                            GPBFieldDescriptor *field,
+                            GPBMessage *parentMessage);
+
+CF_EXTERN_C_END