diff --git a/services/oboeservice/AAudioServiceEndpoint.cpp b/services/oboeservice/AAudioServiceEndpoint.cpp
new file mode 100644
index 0000000..80551c9
--- /dev/null
+++ b/services/oboeservice/AAudioServiceEndpoint.cpp
@@ -0,0 +1,188 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <algorithm>
+#include <mutex>
+#include <vector>
+
+#include "core/AudioStreamBuilder.h"
+#include "AAudioServiceEndpoint.h"
+#include "AAudioServiceStreamShared.h"
+
+using namespace android;  // TODO just import names needed
+using namespace aaudio;   // TODO just import names needed
+
+#define MIN_TIMEOUT_NANOS        (1000 * AAUDIO_NANOS_PER_MILLISECOND)
+
+// Wait at least this many times longer than the operation should take.
+#define MIN_TIMEOUT_OPERATIONS    4
+
+// The mStreamInternal will use a service interface that does not go through Binder.
+AAudioServiceEndpoint::AAudioServiceEndpoint(AAudioService &audioService)
+        : mStreamInternal(audioService, true)
+        {
+}
+
+AAudioServiceEndpoint::~AAudioServiceEndpoint() {
+}
+
+// Set up an EXCLUSIVE MMAP stream that will be shared.
+aaudio_result_t AAudioServiceEndpoint::open(int32_t deviceId, aaudio_direction_t direction) {
+    AudioStreamBuilder builder;
+    builder.setSharingMode(AAUDIO_SHARING_MODE_EXCLUSIVE);
+    builder.setDeviceId(deviceId);
+    builder.setDirection(direction);
+    aaudio_result_t result = mStreamInternal.open(builder);
+    if (result == AAUDIO_OK) {
+        mMixer.allocate(mStreamInternal.getSamplesPerFrame(), mStreamInternal.getFramesPerBurst());
+    }
+    return result;
+}
+
+aaudio_result_t AAudioServiceEndpoint::close() {
+    return mStreamInternal.close();
+}
+
+// TODO, maybe use an interface to reduce exposure
+aaudio_result_t AAudioServiceEndpoint::registerStream(AAudioServiceStreamShared *sharedStream) {
+    ALOGD("AAudioServiceEndpoint::registerStream(%p)", sharedStream);
+    // TODO use real-time technique to avoid mutex, eg. atomic command FIFO
+    std::lock_guard<std::mutex> lock(mLockStreams);
+    mRegisteredStreams.push_back(sharedStream);
+    return AAUDIO_OK;
+}
+
+aaudio_result_t AAudioServiceEndpoint::unregisterStream(AAudioServiceStreamShared *sharedStream) {
+    ALOGD("AAudioServiceEndpoint::unregisterStream(%p)", sharedStream);
+    std::lock_guard<std::mutex> lock(mLockStreams);
+    mRegisteredStreams.erase(std::remove(mRegisteredStreams.begin(), mRegisteredStreams.end(), sharedStream),
+              mRegisteredStreams.end());
+    return AAUDIO_OK;
+}
+
+aaudio_result_t AAudioServiceEndpoint::startStream(AAudioServiceStreamShared *sharedStream) {
+    // TODO use real-time technique to avoid mutex, eg. atomic command FIFO
+    ALOGD("AAudioServiceEndpoint(): startStream() entering");
+    std::lock_guard<std::mutex> lock(mLockStreams);
+    mRunningStreams.push_back(sharedStream);
+    if (mRunningStreams.size() == 1) {
+        startMixer_l();
+    }
+    return AAUDIO_OK;
+}
+
+aaudio_result_t AAudioServiceEndpoint::stopStream(AAudioServiceStreamShared *sharedStream) {
+    std::lock_guard<std::mutex> lock(mLockStreams);
+    mRunningStreams.erase(std::remove(mRunningStreams.begin(), mRunningStreams.end(), sharedStream),
+              mRunningStreams.end());
+    if (mRunningStreams.size() == 0) {
+        stopMixer_l();
+    }
+    return AAUDIO_OK;
+}
+
+static void *aaudio_mixer_thread_proc(void *context) {
+    AAudioServiceEndpoint *stream = (AAudioServiceEndpoint *) context;
+    //LOGD("AudioStreamAAudio(): oboe_callback_thread, stream = %p", stream);
+    if (stream != NULL) {
+        return stream->callbackLoop();
+    } else {
+        return NULL;
+    }
+}
+
+// Render audio in the application callback and then write the data to the stream.
+void *AAudioServiceEndpoint::callbackLoop() {
+    aaudio_result_t result = AAUDIO_OK;
+
+    ALOGD("AAudioServiceEndpoint(): callbackLoop() entering");
+
+    result = mStreamInternal.requestStart();
+    ALOGD("AAudioServiceEndpoint(): callbackLoop() after requestStart()  %d, isPlaying() = %d",
+          result, (int) mStreamInternal.isPlaying());
+
+    // result might be a frame count
+    while (mCallbackEnabled.load() && mStreamInternal.isPlaying() && (result >= 0)) {
+        // Mix data from each active stream.
+        {
+            mMixer.clear();
+            std::lock_guard<std::mutex> lock(mLockStreams);
+            for(AAudioServiceStreamShared *sharedStream : mRunningStreams) {
+                FifoBuffer *fifo = sharedStream->getDataFifoBuffer();
+                float volume = 0.5; // TODO get from system
+                mMixer.mix(fifo, volume);
+            }
+        }
+
+        // Write audio data to stream using a blocking write.
+        ALOGD("AAudioServiceEndpoint(): callbackLoop() write(%d)", getFramesPerBurst());
+        int64_t timeoutNanos = calculateReasonableTimeout(mStreamInternal.getFramesPerBurst());
+        result = mStreamInternal.write(mMixer.getOutputBuffer(), getFramesPerBurst(), timeoutNanos);
+        if (result == AAUDIO_ERROR_DISCONNECTED) {
+            disconnectRegisteredStreams();
+            break;
+        } else if (result != getFramesPerBurst()) {
+            ALOGW("AAudioServiceEndpoint(): callbackLoop() wrote %d / %d",
+                  result, getFramesPerBurst());
+            break;
+        }
+    }
+
+    ALOGD("AAudioServiceEndpoint(): callbackLoop() exiting, result = %d, isPlaying() = %d",
+          result, (int) mStreamInternal.isPlaying());
+
+    result = mStreamInternal.requestStop();
+
+    return NULL; // TODO review
+}
+
+aaudio_result_t AAudioServiceEndpoint::startMixer_l() {
+    // Launch the callback loop thread.
+    int64_t periodNanos = mStreamInternal.getFramesPerBurst()
+                          * AAUDIO_NANOS_PER_SECOND
+                          / getSampleRate();
+    mCallbackEnabled.store(true);
+    return mStreamInternal.createThread(periodNanos, aaudio_mixer_thread_proc, this);
+}
+
+aaudio_result_t AAudioServiceEndpoint::stopMixer_l() {
+    mCallbackEnabled.store(false);
+    return mStreamInternal.joinThread(NULL, calculateReasonableTimeout(mStreamInternal.getFramesPerBurst()));
+}
+
+// TODO Call method in AudioStreamInternal when that callback CL is merged.
+int64_t AAudioServiceEndpoint::calculateReasonableTimeout(int32_t framesPerOperation) {
+
+    // Wait for at least a second or some number of callbacks to join the thread.
+    int64_t timeoutNanoseconds = (MIN_TIMEOUT_OPERATIONS * framesPerOperation * AAUDIO_NANOS_PER_SECOND)
+                                 / getSampleRate();
+    if (timeoutNanoseconds < MIN_TIMEOUT_NANOS) { // arbitrary number of seconds
+        timeoutNanoseconds = MIN_TIMEOUT_NANOS;
+    }
+    return timeoutNanoseconds;
+}
+
+void AAudioServiceEndpoint::disconnectRegisteredStreams() {
+    std::lock_guard<std::mutex> lock(mLockStreams);
+    for(AAudioServiceStreamShared *sharedStream : mRunningStreams) {
+        sharedStream->onStop();
+    }
+    mRunningStreams.clear();
+    for(AAudioServiceStreamShared *sharedStream : mRegisteredStreams) {
+        sharedStream->onDisconnect();
+    }
+    mRegisteredStreams.clear();
+}