@@ -18,6 +18,7 @@ set(USE_LZMA ON CACHE BOOL "Whether or not to enable 7-Zip support")
 set(BUILD_QT ON CACHE BOOL "Build Qt frontend")
 set(BUILD_SDL ON CACHE BOOL "Build SDL frontend")
 set(BUILD_LIBRETRO OFF CACHE BOOL "Build libretro core")
+set(BUILD_OPENEMU OFF CACHE BOOL "Build OpenEmu core")
 set(BUILD_PERF OFF CACHE BOOL "Build performance profiling tool")
 set(BUILD_TEST OFF CACHE BOOL "Build testing harness")
 set(BUILD_STATIC OFF CACHE BOOL "Build a static library")
@@ -556,6 +557,21 @@ add_library(${BINARY_NAME}_libretro SHARED ${CORE_SRC} ${RETRO_SRC})
 	set_target_properties(${BINARY_NAME}_libretro PROPERTIES PREFIX "" COMPILE_DEFINITIONS "COLOR_16_BIT;COLOR_5_6_5;DISABLE_THREADING;${OS_DEFINES};${FUNCTION_DEFINES};MINIMAL_CORE=2")
 	target_link_libraries(${BINARY_NAME}_libretro ${OS_LIB})
 	install(TARGETS ${BINARY_NAME}_libretro LIBRARY DESTINATION ${LIBDIR} COMPONENT ${BINARY_NAME}_libretro NAMELINK_SKIP)
+endif()
+
+if(BUILD_OPENEMU)
+	find_library(FOUNDATION Foundation)
+	find_library(OPENEMUBASE OpenEmuBase)
+	file(GLOB OE_SRC ${CMAKE_SOURCE_DIR}/src/platform/openemu/*.m)
+	add_library(${BINARY_NAME}-openemu MODULE ${CORE_SRC} ${OE_SRC})
+	set_target_properties(${BINARY_NAME}-openemu PROPERTIES
+		MACOSX_BUNDLE_INFO_PLIST ${CMAKE_SOURCE_DIR}/src/platform/openemu/Info.plist.in
+		BUNDLE TRUE
+		BUNDLE_EXTENSION oecoreplugin
+		OUTPUT_NAME ${PROJECT_NAME}EmuCore
+		COMPILE_DEFINITIONS "DISABLE_THREADING;${OS_DEFINES};${FUNCTION_DEFINES};MINIMAL_CORE=2")
+	target_link_libraries(${BINARY_NAME}-openemu ${OS_LIB} ${FOUNDATION} ${OPENEMUBASE})
+	install(TARGETS ${BINARY_NAME}-openemu LIBRARY DESTINATION ${LIBDIR} COMPONENT ${BINARY_NAME}.oecoreplugin NAMELINK_SKIP)
 endif()
 
 if(BUILD_SDL)

@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>CFBundleDevelopmentRegion</key>
+	<string>English</string>
+	<key>CFBundleExecutable</key>
+	<string>${EXECUTABLE_NAME}</string>
+	<key>CFBundleIconFile</key>
+	<string>mGBA</string>
+	<key>CFBundleIdentifier</key>
+	<string>com.endrift.mgba</string>
+	<key>CFBundleInfoDictionaryVersion</key>
+	<string>6.0</string>
+	<key>CFBundlePackageType</key>
+	<string>BNDL</string>
+	<key>CFBundleSignature</key>
+	<string>????</string>
+	<key>CFBundleVersion</key>
+	<string>1.8.0.1232</string>
+	<key>NSPrincipalClass</key>
+	<string>OEGameCoreController</string>
+	<key>OEGameCoreClass</key>
+	<string>mGBAGameCore</string>
+	<key>OEGameCoreOptions</key>
+	<dict>
+		<key>openemu.system.gba</key>
+	</dict>
+	<key>OEGameCorePlayerCount</key>
+	<string>1</string>
+	<key>OEProjectURL</key>
+	<string>https://mgba.io/</string>
+	<key>OESystemIdentifiers</key>
+	<array>
+		<string>openemu.system.gba</string>
+	</array>
+	<key>SUEnableAutomaticChecks</key>
+	<string>1</string>
+	<key>SUFeedURL</key>
+	<string>https://raw.github.com/OpenEmu/OpenEmu-Update/master/mgba_appcast.xml</string>
+</dict>
+</plist>

@@ -0,0 +1,51 @@
+/*
+ Copyright (c) 2011, OpenEmu Team
+ 
+ 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 the OpenEmu Team 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 OpenEmu Team ''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 OpenEmu Team 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 <Cocoa/Cocoa.h>
+
+@protocol OESystemResponderClient;
+
+typedef enum _OEGBAButton
+{
+    OEGBAButtonUp,
+    OEGBAButtonDown,
+    OEGBAButtonLeft,
+    OEGBAButtonRight,
+    OEGBAButtonA,
+    OEGBAButtonB,
+    OEGBAButtonL,
+    OEGBAButtonR,
+    OEGBAButtonStart,
+    OEGBAButtonSelect,
+    OEGBAButtonCount
+} OEGBAButton;
+
+@protocol OEGBASystemResponderClient <OESystemResponderClient, NSObject>
+
+- (oneway void)didPushGBAButton:(OEGBAButton)button forPlayer:(NSUInteger)player;
+- (oneway void)didReleaseGBAButton:(OEGBAButton)button forPlayer:(NSUInteger)player;
+
+@end

@@ -0,0 +1,6 @@
+#import <Cocoa/Cocoa.h>
+#import <OpenEmuBase/OEGameCore.h>
+
+OE_EXPORTED_CLASS
+@interface mGBAGameCore : OEGameCore
+@end

@@ -0,0 +1,251 @@
+/*
+ Copyright (c) 2016, Jeffrey Pfau
+
+ 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.
+
+ 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 HOLDER 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 "mGBAGameCore.h"
+
+#include "util/common.h"
+
+#include "gba/cheats.h"
+#include "gba/renderers/video-software.h"
+#include "gba/serialize.h"
+#include "gba/context/context.h"
+#include "util/circle-buffer.h"
+#include "util/memory.h"
+#include "util/vfs.h"
+
+#import <OpenEmuBase/OERingBuffer.h>
+#import "OEGBASystemResponderClient.h"
+#import <OpenGL/gl.h>
+
+#define SAMPLES 1024
+
+@interface mGBAGameCore () <OEGBASystemResponderClient>
+{
+	struct GBAContext context;
+	struct GBAVideoSoftwareRenderer renderer;
+	struct GBACheatDevice cheats;
+	struct GBACheatSet cheatSet;
+	uint16_t keys;
+}
+@end
+
+@implementation mGBAGameCore
+
+- (id)init
+{
+	if ((self = [super init]))
+	{
+		// TODO: Add a log handler
+		GBAContextInit(&context, 0);
+		struct GBAOptions opts = {
+			.useBios = true,
+			.idleOptimization = IDLE_LOOP_REMOVE
+		};
+		GBAConfigLoadDefaults(&context.config, &opts);
+		GBAVideoSoftwareRendererCreate(&renderer);
+		renderer.outputBuffer = malloc(256 * VIDEO_VERTICAL_PIXELS * BYTES_PER_PIXEL);
+		renderer.outputBufferStride = 256;
+		context.renderer = &renderer.d;
+		GBAAudioResizeBuffer(&context.gba->audio, SAMPLES);
+		GBACheatDeviceCreate(&cheats);
+		GBACheatAttachDevice(context.gba, &cheats);
+		GBACheatSetInit(&cheatSet, "openemu");
+		GBACheatAddSet(&cheats, &cheatSet);
+		keys = 0;
+	}
+
+	return self;
+}
+
+- (void)dealloc
+{
+	GBAContextDeinit(&context);
+	GBACheatRemoveSet(&cheats, &cheatSet);
+	GBACheatDeviceDestroy(&cheats);
+	GBACheatSetDeinit(&cheatSet);
+	free(renderer.outputBuffer);
+
+	[super dealloc];
+}
+
+#pragma mark - Execution
+
+- (BOOL)loadFileAtPath:(NSString *)path error:(NSError **)error
+{
+	UNUSED(error);
+	if (!GBAContextLoadROM(&context, [path UTF8String], true)) {
+		return NO;
+	}
+	GBAContextStart(&context);
+	return YES;
+}
+
+- (void)executeFrame
+{
+	GBAContextFrame(&context, keys);
+
+	int16_t samples[SAMPLES * 2];
+	size_t available = 0;
+#if RESAMPLE_LIBRARY == RESAMPLE_BLIP_BUF
+	available = blip_samples_avail(context.gba->audio.left);
+	blip_read_samples(context.gba->audio.left, samples, available, true);
+	blip_read_samples(context.gba->audio.right, samples + 1, available, true);
+#else
+#error BLIP_BUF is required for now
+#endif
+	[[self ringBufferAtIndex:0] write:samples maxLength:available * 4];
+}
+
+- (void)resetEmulation
+{
+	ARMReset(context.cpu);
+}
+
+- (void)stopEmulation
+{
+	NSLog(@"Stopping");
+	GBAContextStop(&context);
+	[super stopEmulation];
+}
+
+- (void)setupEmulation
+{
+#if RESAMPLE_LIBRARY == RESAMPLE_BLIP_BUF
+	blip_set_rates(context.gba->audio.left,  GBA_ARM7TDMI_FREQUENCY, 32768);
+	blip_set_rates(context.gba->audio.right, GBA_ARM7TDMI_FREQUENCY, 32768);
+#endif
+}
+
+#pragma mark - Video
+
+- (OEIntSize)aspectSize
+{
+	return OEIntSizeMake(3, 2);
+}
+
+- (OEIntRect)screenRect
+{
+    return OEIntRectMake(0, 0, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS);
+}
+
+- (OEIntSize)bufferSize
+{
+    return OEIntSizeMake(256, VIDEO_VERTICAL_PIXELS);
+}
+
+- (const void *)videoBuffer
+{
+	return renderer.outputBuffer;
+}
+
+- (GLenum)pixelFormat
+{
+    return GL_RGBA;
+}
+
+- (GLenum)pixelType
+{
+    return GL_UNSIGNED_INT_8_8_8_8_REV;
+}
+
+- (GLenum)internalPixelFormat
+{
+    return GL_RGB8;
+}
+
+- (NSTimeInterval)frameInterval
+{
+	return GBA_ARM7TDMI_FREQUENCY / (double) VIDEO_TOTAL_LENGTH;
+}
+
+#pragma mark - Audio
+
+- (NSUInteger)channelCount
+{
+    return 2;
+}
+
+- (double)audioSampleRate
+{
+    return 32768;
+}
+
+#pragma mark - Save State
+
+- (NSData *)serializeStateWithError:(NSError **)outError
+{
+	UNUSED(outError);
+	// TODO memory VFile that self-manages memory
+	return nil;
+}
+
+- (BOOL)deserializeState:(NSData *)state withError:(NSError **)outError
+{
+	UNUSED(outError);
+	// TODO VFileFromConstMemory
+	struct VFile* vf = VFileFromMemory((void*) state.bytes, state.length);
+	return GBALoadStateNamed(context.gba, vf, 0);
+}
+
+- (void)saveStateToFileAtPath:(NSString *)fileName completionHandler:(void (^)(BOOL, NSError *))block
+{
+	struct VFile* vf = VFileOpen([fileName UTF8String], O_CREAT | O_TRUNC | O_RDWR);
+	block(GBASaveStateNamed(context.gba, vf, 0), nil);
+}
+
+- (void)loadStateFromFileAtPath:(NSString *)fileName completionHandler:(void (^)(BOOL, NSError *))block
+{
+	struct VFile* vf = VFileOpen([fileName UTF8String], O_RDONLY);
+	block(GBALoadStateNamed(context.gba, vf, 0), nil);
+}
+
+#pragma mark - Input
+
+const int GBAMap[] = {
+	GBA_KEY_UP,
+	GBA_KEY_DOWN,
+	GBA_KEY_LEFT,
+	GBA_KEY_RIGHT,
+	GBA_KEY_A,
+	GBA_KEY_B,
+	GBA_KEY_L,
+	GBA_KEY_R,
+	GBA_KEY_START,
+	GBA_KEY_SELECT
+};
+
+- (oneway void)didPushGBAButton:(OEGBAButton)button forPlayer:(NSUInteger)player
+{
+	UNUSED(player);
+	keys |= 1 << GBAMap[button];
+}
+
+- (oneway void)didReleaseGBAButton:(OEGBAButton)button forPlayer:(NSUInteger)player
+{
+	UNUSED(player);
+	keys &= ~(1 << GBAMap[button]);
+}
+
+@end
+