diff --git a/cartographer_grpc/framework/client_writer.h b/cartographer_grpc/framework/client_writer.h
deleted file mode 100644
index bc4a10c..0000000
--- a/cartographer_grpc/framework/client_writer.h
+++ /dev/null
@@ -1,38 +0,0 @@
-/*
- * Copyright 2018 The Cartographer Authors
- *
- * 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.
- */
-
-#ifndef CARTOGRAPHER_GRPC_FRAMEWORK_CLIENT_WRITER_H_
-#define CARTOGRAPHER_GRPC_FRAMEWORK_CLIENT_WRITER_H_
-
-#include <memory>
-
-#include "google/protobuf/empty.pb.h"
-#include "grpc++/grpc++.h"
-
-namespace cartographer_grpc {
-namespace framework {
-
-template <typename RequestType>
-struct ClientWriter {
-  grpc::ClientContext client_context;
-  std::unique_ptr<grpc::ClientWriter<RequestType>> client_writer;
-  google::protobuf::Empty response;
-};
-
-}  // namespace framework
-}  // namespace cartographer_grpc
-
-#endif  // CARTOGRAPHER_GRPC_FRAMEWORK_CLIENT_WRITER_H_
diff --git a/cartographer_grpc/framework/server_test.cc b/cartographer_grpc/framework/server_test.cc
index 5a97b59..b5cd0a4 100644
--- a/cartographer_grpc/framework/server_test.cc
+++ b/cartographer_grpc/framework/server_test.cc
@@ -20,7 +20,6 @@
 
 #include "cartographer_grpc/framework/client.h"
 #include "cartographer_grpc/framework/execution_context.h"
-#include "cartographer_grpc/framework/proto/math_service.grpc.pb.h"
 #include "cartographer_grpc/framework/proto/math_service.pb.h"
 #include "cartographer_grpc/framework/rpc_handler.h"
 #include "glog/logging.h"
diff --git a/cartographer_grpc/local_trajectory_uploader.cc b/cartographer_grpc/local_trajectory_uploader.cc
index 0aca68e..af596a0 100644
--- a/cartographer_grpc/local_trajectory_uploader.cc
+++ b/cartographer_grpc/local_trajectory_uploader.cc
@@ -15,8 +15,9 @@
  */
 
 #include "cartographer_grpc/local_trajectory_uploader.h"
-
 #include "cartographer/common/make_unique.h"
+#include "cartographer_grpc/handlers/add_trajectory_handler.h"
+#include "cartographer_grpc/handlers/finish_trajectory_handler.h"
 #include "cartographer_grpc/proto/map_builder_service.pb.h"
 #include "cartographer_grpc/sensor/serialization.h"
 #include "glog/logging.h"
@@ -31,22 +32,29 @@ const cartographer::common::Duration kPopTimeout =
 
 LocalTrajectoryUploader::LocalTrajectoryUploader(
     const std::string &uplink_server_address)
-    : client_channel_(grpc::CreateChannel(uplink_server_address,
-                                          grpc::InsecureChannelCredentials())),
-      service_stub_(proto::MapBuilderService::NewStub(client_channel_)) {}
+    : client_channel_(grpc::CreateChannel(
+          uplink_server_address, grpc::InsecureChannelCredentials())) {}
 
 LocalTrajectoryUploader::~LocalTrajectoryUploader() {
-  if (imu_writer_.client_writer) {
-    CHECK(imu_writer_.client_writer->WritesDone());
-    CHECK(imu_writer_.client_writer->Finish().ok());
+  if (add_imu_client_) {
+    CHECK(add_imu_client_->WritesDone());
+    CHECK(add_imu_client_->Finish().ok());
   }
-  if (odometry_writer_.client_writer) {
-    CHECK(odometry_writer_.client_writer->WritesDone());
-    CHECK(odometry_writer_.client_writer->Finish().ok());
+  if (add_odometry_client_) {
+    CHECK(add_odometry_client_->WritesDone());
+    CHECK(add_odometry_client_->Finish().ok());
   }
-  if (fixed_frame_pose_writer_.client_writer) {
-    CHECK(fixed_frame_pose_writer_.client_writer->WritesDone());
-    CHECK(fixed_frame_pose_writer_.client_writer->Finish().ok());
+  if (add_fixed_frame_pose_client_) {
+    CHECK(add_fixed_frame_pose_client_->WritesDone());
+    CHECK(add_fixed_frame_pose_client_->Finish().ok());
+  }
+  if (add_local_slam_result_client_) {
+    CHECK(add_local_slam_result_client_->WritesDone());
+    CHECK(add_local_slam_result_client_->Finish().ok());
+  }
+  if (add_landmark_client_) {
+    CHECK(add_landmark_client_->WritesDone());
+    CHECK(add_landmark_client_->Finish().ok());
   }
 }
 
@@ -84,6 +92,10 @@ void LocalTrajectoryUploader::ProcessSendQueue() {
                      dynamic_cast<proto::AddLocalSlamResultDataRequest *>(
                          data_message.get())) {
         ProcessLocalSlamResultDataMessage(local_slam_result_data);
+      } else if (auto *landmark_data =
+                     dynamic_cast<proto::AddLandmarkDataRequest *>(
+                         data_message.get())) {
+        ProcessLandmarkDataMessage(landmark_data);
       } else {
         LOG(FATAL) << "Unknown message type: " << data_message->GetTypeName();
       }
@@ -100,47 +112,51 @@ void LocalTrajectoryUploader::TranslateTrajectoryId(
 
 void LocalTrajectoryUploader::ProcessFixedFramePoseDataMessage(
     proto::AddFixedFramePoseDataRequest *data_request) {
-  if (!fixed_frame_pose_writer_.client_writer) {
-    fixed_frame_pose_writer_.client_writer =
-        service_stub_->AddFixedFramePoseData(
-            &fixed_frame_pose_writer_.client_context,
-            &fixed_frame_pose_writer_.response);
-    CHECK(fixed_frame_pose_writer_.client_writer);
+  if (!add_fixed_frame_pose_client_) {
+    add_fixed_frame_pose_client_ = cartographer::common::make_unique<
+        framework::Client<handlers::AddFixedFramePoseDataHandler>>(
+        client_channel_);
   }
   TranslateTrajectoryId(data_request->mutable_sensor_metadata());
-  fixed_frame_pose_writer_.client_writer->Write(*data_request);
+  CHECK(add_fixed_frame_pose_client_->Write(*data_request));
 }
 
 void LocalTrajectoryUploader::ProcessImuDataMessage(
     proto::AddImuDataRequest *data_request) {
-  if (!imu_writer_.client_writer) {
-    imu_writer_.client_writer = service_stub_->AddImuData(
-        &imu_writer_.client_context, &imu_writer_.response);
-    CHECK(imu_writer_.client_writer);
+  if (!add_imu_client_) {
+    add_imu_client_ = cartographer::common::make_unique<
+        framework::Client<handlers::AddImuDataHandler>>(client_channel_);
   }
   TranslateTrajectoryId(data_request->mutable_sensor_metadata());
-  imu_writer_.client_writer->Write(*data_request);
+  CHECK(add_imu_client_->Write(*data_request));
 }
 
 void LocalTrajectoryUploader::ProcessOdometryDataMessage(
     proto::AddOdometryDataRequest *data_request) {
-  if (!odometry_writer_.client_writer) {
-    odometry_writer_.client_writer = service_stub_->AddOdometryData(
-        &odometry_writer_.client_context, &odometry_writer_.response);
-    CHECK(odometry_writer_.client_writer);
+  if (!add_odometry_client_) {
+    add_odometry_client_ = cartographer::common::make_unique<
+        framework::Client<handlers::AddOdometryDataHandler>>(client_channel_);
   }
   TranslateTrajectoryId(data_request->mutable_sensor_metadata());
-  odometry_writer_.client_writer->Write(*data_request);
+  CHECK(add_odometry_client_->Write(*data_request));
+}
+
+void LocalTrajectoryUploader::ProcessLandmarkDataMessage(
+    proto::AddLandmarkDataRequest *data_request) {
+  if (!add_landmark_client_) {
+    add_landmark_client_ = cartographer::common::make_unique<
+        framework::Client<handlers::AddLandmarkDataHandler>>(client_channel_);
+  }
+  TranslateTrajectoryId(data_request->mutable_sensor_metadata());
+  CHECK(add_landmark_client_->Write(*data_request));
 }
 
 void LocalTrajectoryUploader::ProcessLocalSlamResultDataMessage(
     proto::AddLocalSlamResultDataRequest *data_request) {
-  if (!local_slam_result_writer_.client_writer) {
-    local_slam_result_writer_.client_writer =
-        service_stub_->AddLocalSlamResultData(
-            &local_slam_result_writer_.client_context,
-            &local_slam_result_writer_.response);
-    CHECK(local_slam_result_writer_.client_writer);
+  if (!add_local_slam_result_client_) {
+    add_local_slam_result_client_ = cartographer::common::make_unique<
+        framework::Client<handlers::AddLocalSlamResultDataHandler>>(
+        client_channel_);
   }
   TranslateTrajectoryId(data_request->mutable_sensor_metadata());
   // A submap also holds a trajectory id that must be translated to uplink's
@@ -150,16 +166,14 @@ void LocalTrajectoryUploader::ProcessLocalSlamResultDataMessage(
     mutable_submap.mutable_submap_id()->set_trajectory_id(
         data_request->sensor_metadata().trajectory_id());
   }
-  local_slam_result_writer_.client_writer->Write(*data_request);
+  CHECK(add_local_slam_result_client_->Write(*data_request));
 }
 
 void LocalTrajectoryUploader::AddTrajectory(
     int local_trajectory_id, const std::set<SensorId> &expected_sensor_ids,
     const cartographer::mapping::proto::TrajectoryBuilderOptions
         &trajectory_options) {
-  grpc::ClientContext client_context;
   proto::AddTrajectoryRequest request;
-  proto::AddTrajectoryResponse result;
   *request.mutable_trajectory_builder_options() = trajectory_options;
   for (const SensorId &sensor_id : expected_sensor_ids) {
     // Range sensors are not forwarded, but combined into a LocalSlamResult.
@@ -169,25 +183,21 @@ void LocalTrajectoryUploader::AddTrajectory(
   }
   *request.add_expected_sensor_ids() =
       sensor::ToProto(GetLocalSlamResultSensorId(local_trajectory_id));
-  grpc::Status status =
-      service_stub_->AddTrajectory(&client_context, request, &result);
-  CHECK(status.ok());
+  framework::Client<handlers::AddTrajectoryHandler> client(client_channel_);
+  CHECK(client.Write(request));
   CHECK_EQ(local_to_cloud_trajectory_id_map_.count(local_trajectory_id), 0);
   local_to_cloud_trajectory_id_map_[local_trajectory_id] =
-      result.trajectory_id();
+      client.response().trajectory_id();
 }
 
 void LocalTrajectoryUploader::FinishTrajectory(int local_trajectory_id) {
   CHECK_EQ(local_to_cloud_trajectory_id_map_.count(local_trajectory_id), 1);
   int cloud_trajectory_id =
       local_to_cloud_trajectory_id_map_[local_trajectory_id];
-  grpc::ClientContext client_context;
   proto::FinishTrajectoryRequest request;
-  google::protobuf::Empty response;
   request.set_trajectory_id(cloud_trajectory_id);
-  grpc::Status status =
-      service_stub_->FinishTrajectory(&client_context, request, &response);
-  CHECK(status.ok());
+  framework::Client<handlers::FinishTrajectoryHandler> client(client_channel_);
+  CHECK(client.Write(request));
 }
 
 void LocalTrajectoryUploader::EnqueueDataRequest(
diff --git a/cartographer_grpc/local_trajectory_uploader.h b/cartographer_grpc/local_trajectory_uploader.h
index 1eb3cd5..6ca4763 100644
--- a/cartographer_grpc/local_trajectory_uploader.h
+++ b/cartographer_grpc/local_trajectory_uploader.h
@@ -26,8 +26,13 @@
 #include "cartographer/common/blocking_queue.h"
 #include "cartographer/mapping/proto/trajectory_builder_options.pb.h"
 #include "cartographer/mapping/trajectory_builder_interface.h"
-#include "cartographer_grpc/framework/client_writer.h"
-#include "cartographer_grpc/proto/map_builder_service.grpc.pb.h"
+#include "cartographer_grpc/framework/client.h"
+#include "cartographer_grpc/handlers/add_fixed_frame_pose_data_handler.h"
+#include "cartographer_grpc/handlers/add_imu_data_handler.h"
+#include "cartographer_grpc/handlers/add_landmark_data_handler.h"
+#include "cartographer_grpc/handlers/add_local_slam_result_data_handler.h"
+#include "cartographer_grpc/handlers/add_odometry_data_handler.h"
+#include "cartographer_grpc/proto/map_builder_service.pb.h"
 #include "grpc++/grpc++.h"
 
 namespace cartographer_grpc {
@@ -85,21 +90,25 @@ class LocalTrajectoryUploader : public LocalTrajectoryUploaderInterface {
   void ProcessLocalSlamResultDataMessage(
       proto::AddLocalSlamResultDataRequest* data_request);
   void ProcessOdometryDataMessage(proto::AddOdometryDataRequest* data_request);
+  void ProcessLandmarkDataMessage(proto::AddLandmarkDataRequest* data_request);
 
   std::shared_ptr<grpc::Channel> client_channel_;
-  std::unique_ptr<proto::MapBuilderService::Stub> service_stub_;
   std::map<int, int> local_to_cloud_trajectory_id_map_;
   cartographer::common::BlockingQueue<
       std::unique_ptr<google::protobuf::Message>>
       send_queue_;
   bool shutting_down_ = false;
   std::unique_ptr<std::thread> upload_thread_;
-  framework::ClientWriter<proto::AddFixedFramePoseDataRequest>
-      fixed_frame_pose_writer_;
-  framework::ClientWriter<proto::AddImuDataRequest> imu_writer_;
-  framework::ClientWriter<proto::AddLocalSlamResultDataRequest>
-      local_slam_result_writer_;
-  framework::ClientWriter<proto::AddOdometryDataRequest> odometry_writer_;
+  std::unique_ptr<framework::Client<handlers::AddFixedFramePoseDataHandler>>
+      add_fixed_frame_pose_client_;
+  std::unique_ptr<framework::Client<handlers::AddImuDataHandler>>
+      add_imu_client_;
+  std::unique_ptr<framework::Client<handlers::AddLocalSlamResultDataHandler>>
+      add_local_slam_result_client_;
+  std::unique_ptr<framework::Client<handlers::AddOdometryDataHandler>>
+      add_odometry_client_;
+  std::unique_ptr<framework::Client<handlers::AddLandmarkDataHandler>>
+      add_landmark_client_;
 };
 
 }  // namespace cartographer_grpc
diff --git a/cartographer_grpc/map_builder_server.cc b/cartographer_grpc/map_builder_server.cc
index 9f53ad5..449d873 100644
--- a/cartographer_grpc/map_builder_server.cc
+++ b/cartographer_grpc/map_builder_server.cc
@@ -33,7 +33,6 @@
 #include "cartographer_grpc/handlers/receive_local_slam_results_handler.h"
 #include "cartographer_grpc/handlers/run_final_optimization_handler.h"
 #include "cartographer_grpc/handlers/write_map_handler.h"
-#include "cartographer_grpc/proto/map_builder_service.grpc.pb.h"
 #include "cartographer_grpc/sensor/serialization.h"
 #include "glog/logging.h"
 
diff --git a/cartographer_grpc/mapping/map_builder_stub.cc b/cartographer_grpc/mapping/map_builder_stub.cc
index b498cc8..52af0ef 100644
--- a/cartographer_grpc/mapping/map_builder_stub.cc
+++ b/cartographer_grpc/mapping/map_builder_stub.cc
@@ -15,7 +15,11 @@
  */
 
 #include "cartographer_grpc/mapping/map_builder_stub.h"
-
+#include "cartographer_grpc/handlers/add_trajectory_handler.h"
+#include "cartographer_grpc/handlers/finish_trajectory_handler.h"
+#include "cartographer_grpc/handlers/get_submap_handler.h"
+#include "cartographer_grpc/handlers/load_map_handler.h"
+#include "cartographer_grpc/handlers/write_map_handler.h"
 #include "cartographer_grpc/proto/map_builder_service.pb.h"
 #include "cartographer_grpc/sensor/serialization.h"
 #include "glog/logging.h"
@@ -26,33 +30,30 @@ namespace mapping {
 MapBuilderStub::MapBuilderStub(const std::string& server_address)
     : client_channel_(grpc::CreateChannel(server_address,
                                           grpc::InsecureChannelCredentials())),
-      service_stub_(proto::MapBuilderService::NewStub(client_channel_)),
-      pose_graph_stub_(client_channel_, service_stub_.get()) {}
+      pose_graph_stub_(client_channel_) {}
 
 int MapBuilderStub::AddTrajectoryBuilder(
     const std::set<SensorId>& expected_sensor_ids,
     const cartographer::mapping::proto::TrajectoryBuilderOptions&
         trajectory_options,
     LocalSlamResultCallback local_slam_result_callback) {
-  grpc::ClientContext client_context;
   proto::AddTrajectoryRequest request;
-  proto::AddTrajectoryResponse result;
   *request.mutable_trajectory_builder_options() = trajectory_options;
   for (const auto& sensor_id : expected_sensor_ids) {
     *request.add_expected_sensor_ids() = sensor::ToProto(sensor_id);
   }
-  grpc::Status status =
-      service_stub_->AddTrajectory(&client_context, request, &result);
-  CHECK(status.ok());
+  framework::Client<handlers::AddTrajectoryHandler> client(client_channel_);
+  CHECK(client.Write(request));
 
   // Construct trajectory builder stub.
   trajectory_builder_stubs_.emplace(
-      std::piecewise_construct, std::forward_as_tuple(result.trajectory_id()),
+      std::piecewise_construct,
+      std::forward_as_tuple(client.response().trajectory_id()),
       std::forward_as_tuple(cartographer::common::make_unique<
                             cartographer_grpc::mapping::TrajectoryBuilderStub>(
-          client_channel_, result.trajectory_id(),
+          client_channel_, client.response().trajectory_id(),
           local_slam_result_callback)));
-  return result.trajectory_id();
+  return client.response().trajectory_id();
 }
 
 int MapBuilderStub::AddTrajectoryForDeserialization() {
@@ -65,13 +66,10 @@ MapBuilderStub::GetTrajectoryBuilder(int trajectory_id) const {
 }
 
 void MapBuilderStub::FinishTrajectory(int trajectory_id) {
-  grpc::ClientContext client_context;
   proto::FinishTrajectoryRequest request;
-  google::protobuf::Empty response;
   request.set_trajectory_id(trajectory_id);
-  grpc::Status status =
-      service_stub_->FinishTrajectory(&client_context, request, &response);
-  CHECK(status.ok());
+  framework::Client<handlers::FinishTrajectoryHandler> client(client_channel_);
+  CHECK(client.Write(request));
   trajectory_builder_stubs_.erase(trajectory_id);
 }
 
@@ -79,22 +77,21 @@ std::string MapBuilderStub::SubmapToProto(
     const cartographer::mapping::SubmapId& submap_id,
     cartographer::mapping::proto::SubmapQuery::Response*
         submap_query_response) {
-  grpc::ClientContext client_context;
   proto::GetSubmapRequest request;
   submap_id.ToProto(request.mutable_submap_id());
-  proto::GetSubmapResponse response;
-  CHECK(service_stub_->GetSubmap(&client_context, request, &response).ok());
-  submap_query_response->CopyFrom(response.submap_query_response());
-  return response.error_msg();
+  framework::Client<handlers::GetSubmapHandler> client(client_channel_);
+  CHECK(client.Write(request));
+  submap_query_response->CopyFrom(client.response().submap_query_response());
+  return client.response().error_msg();
 }
 
 void MapBuilderStub::SerializeState(
     cartographer::io::ProtoStreamWriterInterface* writer) {
-  grpc::ClientContext client_context;
   google::protobuf::Empty request;
-  auto reader = service_stub_->WriteMap(&client_context, request);
+  framework::Client<handlers::WriteMapHandler> client(client_channel_);
+  CHECK(client.Write(request));
   proto::WriteMapResponse response;
-  while (reader->Read(&response)) {
+  while (client.Read(&response)) {
     writer->WriteProto(response);
   }
   CHECK(writer->Close());
@@ -102,26 +99,22 @@ void MapBuilderStub::SerializeState(
 
 void MapBuilderStub::LoadMap(
     cartographer::io::ProtoStreamReaderInterface* reader) {
-  framework::ClientWriter<proto::LoadMapRequest> load_map_writer;
-  load_map_writer.client_writer = service_stub_->LoadMap(
-      &load_map_writer.client_context, &load_map_writer.response);
-  CHECK(load_map_writer.client_writer);
-
+  framework::Client<handlers::LoadMapHandler> client(client_channel_);
   // Request with a PoseGraph proto is sent first.
   {
     proto::LoadMapRequest request;
     CHECK(reader->ReadProto(request.mutable_pose_graph()));
-    CHECK(load_map_writer.client_writer->Write(request));
+    CHECK(client.Write(request));
   }
-
   // Multiple requests with SerializedData are sent after.
   proto::LoadMapRequest request;
   while (reader->ReadProto(request.mutable_serialized_data())) {
-    CHECK(load_map_writer.client_writer->Write(request));
+    CHECK(client.Write(request));
   }
 
   CHECK(reader->eof());
-  CHECK(load_map_writer.client_writer->WritesDone());
+  CHECK(client.WritesDone());
+  CHECK(client.Finish().ok());
 }
 
 int MapBuilderStub::num_trajectory_builders() const {
diff --git a/cartographer_grpc/mapping/map_builder_stub.h b/cartographer_grpc/mapping/map_builder_stub.h
index 7bb98d8..f9f7447 100644
--- a/cartographer_grpc/mapping/map_builder_stub.h
+++ b/cartographer_grpc/mapping/map_builder_stub.h
@@ -22,7 +22,6 @@
 #include "cartographer/mapping/map_builder_interface.h"
 #include "cartographer_grpc/mapping/pose_graph_stub.h"
 #include "cartographer_grpc/mapping/trajectory_builder_stub.h"
-#include "cartographer_grpc/proto/map_builder_service.grpc.pb.h"
 #include "grpc++/grpc++.h"
 
 namespace cartographer_grpc {
@@ -55,7 +54,6 @@ class MapBuilderStub : public cartographer::mapping::MapBuilderInterface {
 
  private:
   std::shared_ptr<grpc::Channel> client_channel_;
-  std::unique_ptr<proto::MapBuilderService::Stub> service_stub_;
   PoseGraphStub pose_graph_stub_;
   std::map<int, std::unique_ptr<TrajectoryBuilderStub>>
       trajectory_builder_stubs_;
diff --git a/cartographer_grpc/mapping/pose_graph_stub.cc b/cartographer_grpc/mapping/pose_graph_stub.cc
index fe8ca55..e4e5bbd 100644
--- a/cartographer_grpc/mapping/pose_graph_stub.cc
+++ b/cartographer_grpc/mapping/pose_graph_stub.cc
@@ -15,22 +15,26 @@
  */
 
 #include "cartographer_grpc/mapping/pose_graph_stub.h"
-
 #include "cartographer/mapping/pose_graph.h"
+#include "cartographer_grpc/framework/client.h"
+#include "cartographer_grpc/handlers/get_all_submap_poses.h"
+#include "cartographer_grpc/handlers/get_constraints_handler.h"
+#include "cartographer_grpc/handlers/get_local_to_global_transform_handler.h"
+#include "cartographer_grpc/handlers/get_trajectory_node_poses_handler.h"
+#include "cartographer_grpc/handlers/run_final_optimization_handler.h"
 #include "glog/logging.h"
 
 namespace cartographer_grpc {
 namespace mapping {
 
-PoseGraphStub::PoseGraphStub(std::shared_ptr<grpc::Channel> client_channel,
-                             proto::MapBuilderService::Stub* stub)
-    : client_channel_(client_channel), stub_(stub) {}
+PoseGraphStub::PoseGraphStub(std::shared_ptr<grpc::Channel> client_channel)
+    : client_channel_(client_channel) {}
 
 void PoseGraphStub::RunFinalOptimization() {
-  grpc::ClientContext client_context;
   google::protobuf::Empty request;
-  google::protobuf::Empty response;
-  CHECK(stub_->RunFinalOptimization(&client_context, request, &response).ok());
+  framework::Client<handlers::RunFinalOptimizationHandler> client(
+      client_channel_);
+  CHECK(client.Write(request));
 }
 
 cartographer::mapping::MapById<
@@ -44,15 +48,14 @@ cartographer::mapping::MapById<
     cartographer::mapping::SubmapId,
     cartographer::mapping::PoseGraphInterface::SubmapPose>
 PoseGraphStub::GetAllSubmapPoses() {
-  grpc::ClientContext client_context;
   google::protobuf::Empty request;
-  proto::GetAllSubmapPosesResponse response;
-  stub_->GetAllSubmapPoses(&client_context, request, &response);
+  framework::Client<handlers::GetAllSubmapPosesHandler> client(client_channel_);
+  CHECK(client.Write(request));
   cartographer::mapping::MapById<
       cartographer::mapping::SubmapId,
       cartographer::mapping::PoseGraphInterface::SubmapPose>
       submap_poses;
-  for (const auto& submap_pose : response.submap_poses()) {
+  for (const auto& submap_pose : client.response().submap_poses()) {
     submap_poses.Insert(
         cartographer::mapping::SubmapId{submap_pose.submap_id().trajectory_id(),
                                         submap_pose.submap_id().submap_index()},
@@ -65,13 +68,12 @@ PoseGraphStub::GetAllSubmapPoses() {
 
 cartographer::transform::Rigid3d PoseGraphStub::GetLocalToGlobalTransform(
     int trajectory_id) {
-  grpc::ClientContext client_context;
   proto::GetLocalToGlobalTransformRequest request;
   request.set_trajectory_id(trajectory_id);
-  proto::GetLocalToGlobalTransformResponse response;
-  CHECK(stub_->GetLocalToGlobalTransform(&client_context, request, &response)
-            .ok());
-  return cartographer::transform::ToRigid3(response.local_to_global());
+  framework::Client<handlers::GetLocalToGlobalTransformHandler> client(
+      client_channel_);
+  CHECK(client.Write(request));
+  return cartographer::transform::ToRigid3(client.response().local_to_global());
 }
 
 cartographer::mapping::MapById<cartographer::mapping::NodeId,
@@ -83,14 +85,14 @@ PoseGraphStub::GetTrajectoryNodes() {
 cartographer::mapping::MapById<cartographer::mapping::NodeId,
                                cartographer::mapping::TrajectoryNodePose>
 PoseGraphStub::GetTrajectoryNodePoses() {
-  grpc::ClientContext client_context;
   google::protobuf::Empty request;
-  proto::GetTrajectoryNodePosesResponse response;
-  stub_->GetTrajectoryNodePoses(&client_context, request, &response);
+  framework::Client<handlers::GetTrajectoryNodePosesHandler> client(
+      client_channel_);
+  CHECK(client.Write(request));
   cartographer::mapping::MapById<cartographer::mapping::NodeId,
                                  cartographer::mapping::TrajectoryNodePose>
       node_poses;
-  for (const auto& node_pose : response.node_poses()) {
+  for (const auto& node_pose : client.response().node_poses()) {
     node_poses.Insert(
         cartographer::mapping::NodeId{node_pose.node_id().trajectory_id(),
                                       node_pose.node_id().node_index()},
@@ -107,11 +109,10 @@ bool PoseGraphStub::IsTrajectoryFinished(int trajectory_id) {
 
 std::vector<cartographer::mapping::PoseGraphInterface::Constraint>
 PoseGraphStub::constraints() {
-  grpc::ClientContext client_context;
   google::protobuf::Empty request;
-  proto::GetConstraintsResponse response;
-  stub_->GetConstraints(&client_context, request, &response);
-  return cartographer::mapping::FromProto(response.constraints());
+  framework::Client<handlers::GetConstraintsHandler> client(client_channel_);
+  CHECK(client.Write(request));
+  return cartographer::mapping::FromProto(client.response().constraints());
 }
 
 cartographer::mapping::proto::PoseGraph PoseGraphStub::ToProto() {
diff --git a/cartographer_grpc/mapping/pose_graph_stub.h b/cartographer_grpc/mapping/pose_graph_stub.h
index 92c1f22..9f5c740 100644
--- a/cartographer_grpc/mapping/pose_graph_stub.h
+++ b/cartographer_grpc/mapping/pose_graph_stub.h
@@ -18,7 +18,6 @@
 #define CARTOGRAPHER_GRPC_MAPPING_POSE_GRAPH_STUB_H_
 
 #include "cartographer/mapping/pose_graph_interface.h"
-#include "cartographer_grpc/proto/map_builder_service.grpc.pb.h"
 #include "grpc++/grpc++.h"
 
 namespace cartographer_grpc {
@@ -26,8 +25,7 @@ namespace mapping {
 
 class PoseGraphStub : public cartographer::mapping::PoseGraphInterface {
  public:
-  PoseGraphStub(std::shared_ptr<grpc::Channel> client_channel,
-                proto::MapBuilderService::Stub* stub);
+  PoseGraphStub(std::shared_ptr<grpc::Channel> client_channel);
 
   PoseGraphStub(const PoseGraphStub&) = delete;
   PoseGraphStub& operator=(const PoseGraphStub&) = delete;
@@ -51,7 +49,6 @@ class PoseGraphStub : public cartographer::mapping::PoseGraphInterface {
 
  private:
   std::shared_ptr<grpc::Channel> client_channel_;
-  proto::MapBuilderService::Stub* stub_;
 };
 
 }  // namespace mapping
diff --git a/cartographer_grpc/mapping/trajectory_builder_stub.cc b/cartographer_grpc/mapping/trajectory_builder_stub.cc
index cd1376e..8a78afc 100644
--- a/cartographer_grpc/mapping/trajectory_builder_stub.cc
+++ b/cartographer_grpc/mapping/trajectory_builder_stub.cc
@@ -27,119 +27,121 @@ namespace mapping {
 TrajectoryBuilderStub::TrajectoryBuilderStub(
     std::shared_ptr<grpc::Channel> client_channel, const int trajectory_id,
     LocalSlamResultCallback local_slam_result_callback)
-    : client_channel_(client_channel), trajectory_id_(trajectory_id) {
-  stub_ = proto::MapBuilderService::NewStub(client_channel_);
-  CHECK(stub_) << "Failed to create stub.";
+    : client_channel_(client_channel),
+      trajectory_id_(trajectory_id),
+      receive_local_slam_results_client_(client_channel_) {
   if (local_slam_result_callback) {
     proto::ReceiveLocalSlamResultsRequest request;
     request.set_trajectory_id(trajectory_id);
-    local_slam_result_reader_.client_reader = stub_->ReceiveLocalSlamResults(
-        &local_slam_result_reader_.client_context, request);
-    auto* client_reader_ptr = local_slam_result_reader_.client_reader.get();
-    local_slam_result_reader_.thread =
+    receive_local_slam_results_client_.Write(request);
+    auto* receive_local_slam_results_client_ptr =
+        &receive_local_slam_results_client_;
+    receive_local_slam_results_thread_ =
         cartographer::common::make_unique<std::thread>(
-            [client_reader_ptr, local_slam_result_callback]() {
-              RunLocalSlamResultReader(client_reader_ptr,
-                                       local_slam_result_callback);
+            [receive_local_slam_results_client_ptr,
+             local_slam_result_callback]() {
+              RunLocalSlamResultsReader(receive_local_slam_results_client_ptr,
+                                        local_slam_result_callback);
             });
   }
 }
 
 TrajectoryBuilderStub::~TrajectoryBuilderStub() {
-  if (local_slam_result_reader_.thread) {
-    local_slam_result_reader_.thread->join();
+  if (receive_local_slam_results_thread_) {
+    receive_local_slam_results_thread_->join();
   }
-  if (rangefinder_writer_.client_writer) {
-    CHECK(rangefinder_writer_.client_writer->WritesDone());
-    CHECK(rangefinder_writer_.client_writer->Finish().ok());
+  if (add_rangefinder_client_) {
+    CHECK(add_rangefinder_client_->WritesDone());
+    CHECK(add_rangefinder_client_->Finish().ok());
   }
-  if (imu_writer_.client_writer) {
-    CHECK(imu_writer_.client_writer->WritesDone());
-    CHECK(imu_writer_.client_writer->Finish().ok());
+  if (add_imu_client_) {
+    CHECK(add_imu_client_->WritesDone());
+    CHECK(add_imu_client_->Finish().ok());
   }
-  if (odometry_writer_.client_writer) {
-    CHECK(odometry_writer_.client_writer->WritesDone());
-    CHECK(odometry_writer_.client_writer->Finish().ok());
+  if (add_odometry_client_) {
+    CHECK(add_odometry_client_->WritesDone());
+    CHECK(add_odometry_client_->Finish().ok());
   }
-  if (fixed_frame_writer_.client_writer) {
-    CHECK(fixed_frame_writer_.client_writer->WritesDone());
-    CHECK(fixed_frame_writer_.client_writer->Finish().ok());
+  if (add_landmark_client_) {
+    CHECK(add_landmark_client_->WritesDone());
+    CHECK(add_landmark_client_->Finish().ok());
+  }
+  if (add_fixed_frame_pose_client_) {
+    CHECK(add_fixed_frame_pose_client_->WritesDone());
+    CHECK(add_fixed_frame_pose_client_->Finish().ok());
   }
 }
 
 void TrajectoryBuilderStub::AddSensorData(
     const std::string& sensor_id,
     const cartographer::sensor::TimedPointCloudData& timed_point_cloud_data) {
-  if (!rangefinder_writer_.client_writer) {
-    rangefinder_writer_.client_writer = stub_->AddRangefinderData(
-        &rangefinder_writer_.client_context, &rangefinder_writer_.response);
-    CHECK(rangefinder_writer_.client_writer);
+  if (!add_rangefinder_client_) {
+    add_rangefinder_client_ = cartographer::common::make_unique<
+        framework::Client<handlers::AddRangefinderDataHandler>>(
+        client_channel_);
   }
   proto::AddRangefinderDataRequest request;
   sensor::CreateAddRangeFinderDataRequest(
       sensor_id, trajectory_id_,
       cartographer::sensor::ToProto(timed_point_cloud_data), &request);
-  rangefinder_writer_.client_writer->Write(request);
+  add_rangefinder_client_->Write(request);
 }
 
 void TrajectoryBuilderStub::AddSensorData(
     const std::string& sensor_id,
     const cartographer::sensor::ImuData& imu_data) {
-  if (!imu_writer_.client_writer) {
-    imu_writer_.client_writer =
-        stub_->AddImuData(&imu_writer_.client_context, &imu_writer_.response);
-    CHECK(imu_writer_.client_writer);
+  if (!add_imu_client_) {
+    add_imu_client_ = cartographer::common::make_unique<
+        framework::Client<handlers::AddImuDataHandler>>(client_channel_);
   }
   proto::AddImuDataRequest request;
   sensor::CreateAddImuDataRequest(sensor_id, trajectory_id_,
                                   cartographer::sensor::ToProto(imu_data),
                                   &request);
-  imu_writer_.client_writer->Write(request);
+  add_imu_client_->Write(request);
 }
 
 void TrajectoryBuilderStub::AddSensorData(
     const std::string& sensor_id,
     const cartographer::sensor::OdometryData& odometry_data) {
-  if (!odometry_writer_.client_writer) {
-    odometry_writer_.client_writer = stub_->AddOdometryData(
-        &odometry_writer_.client_context, &odometry_writer_.response);
-    CHECK(odometry_writer_.client_writer);
+  if (!add_odometry_client_) {
+    add_odometry_client_ = cartographer::common::make_unique<
+        framework::Client<handlers::AddOdometryDataHandler>>(client_channel_);
   }
   proto::AddOdometryDataRequest request;
   sensor::CreateAddOdometryDataRequest(
       sensor_id, trajectory_id_, cartographer::sensor::ToProto(odometry_data),
       &request);
-  odometry_writer_.client_writer->Write(request);
+  add_odometry_client_->Write(request);
 }
 
 void TrajectoryBuilderStub::AddSensorData(
     const std::string& sensor_id,
     const cartographer::sensor::FixedFramePoseData& fixed_frame_pose) {
-  if (!fixed_frame_writer_.client_writer) {
-    fixed_frame_writer_.client_writer = stub_->AddFixedFramePoseData(
-        &fixed_frame_writer_.client_context, &fixed_frame_writer_.response);
-    CHECK(fixed_frame_writer_.client_writer);
+  if (!add_fixed_frame_pose_client_) {
+    add_fixed_frame_pose_client_ = cartographer::common::make_unique<
+        framework::Client<handlers::AddFixedFramePoseDataHandler>>(
+        client_channel_);
   }
   proto::AddFixedFramePoseDataRequest request;
   sensor::CreateAddFixedFramePoseDataRequest(
       sensor_id, trajectory_id_,
       cartographer::sensor::ToProto(fixed_frame_pose), &request);
-  fixed_frame_writer_.client_writer->Write(request);
+  add_fixed_frame_pose_client_->Write(request);
 }
 
 void TrajectoryBuilderStub::AddSensorData(
     const std::string& sensor_id,
     const cartographer::sensor::LandmarkData& landmark_data) {
-  if (!landmark_writer_.client_writer) {
-    landmark_writer_.client_writer = stub_->AddLandmarkData(
-        &landmark_writer_.client_context, &landmark_writer_.response);
-    CHECK(landmark_writer_.client_writer);
+  if (!add_landmark_client_) {
+    add_landmark_client_ = cartographer::common::make_unique<
+        framework::Client<handlers::AddLandmarkDataHandler>>(client_channel_);
   }
   proto::AddLandmarkDataRequest request;
   sensor::CreateAddLandmarkDataRequest(
       sensor_id, trajectory_id_, cartographer::sensor::ToProto(landmark_data),
       &request);
-  landmark_writer_.client_writer->Write(request);
+  add_landmark_client_->Write(request);
 }
 
 void TrajectoryBuilderStub::AddLocalSlamResultData(
@@ -148,11 +150,11 @@ void TrajectoryBuilderStub::AddLocalSlamResultData(
   LOG(FATAL) << "Not implemented";
 }
 
-void TrajectoryBuilderStub::RunLocalSlamResultReader(
-    grpc::ClientReader<proto::ReceiveLocalSlamResultsResponse>* client_reader,
+void TrajectoryBuilderStub::RunLocalSlamResultsReader(
+    framework::Client<handlers::ReceiveLocalSlamResultsHandler>* client,
     LocalSlamResultCallback local_slam_result_callback) {
   proto::ReceiveLocalSlamResultsResponse response;
-  while (client_reader->Read(&response)) {
+  while (client->Read(&response)) {
     int trajectory_id = response.trajectory_id();
     cartographer::common::Time time =
         cartographer::common::FromUniversal(response.timestamp());
@@ -170,7 +172,7 @@ void TrajectoryBuilderStub::RunLocalSlamResultReader(
     local_slam_result_callback(trajectory_id, time, local_pose, range_data,
                                std::move(insertion_result));
   }
-  client_reader->Finish();
+  client->Finish();
 }
 
 }  // namespace mapping
diff --git a/cartographer_grpc/mapping/trajectory_builder_stub.h b/cartographer_grpc/mapping/trajectory_builder_stub.h
index a5e324f..7095ae5 100644
--- a/cartographer_grpc/mapping/trajectory_builder_stub.h
+++ b/cartographer_grpc/mapping/trajectory_builder_stub.h
@@ -21,8 +21,14 @@
 
 #include "cartographer/mapping/local_slam_result_data.h"
 #include "cartographer/mapping/trajectory_builder_interface.h"
-#include "cartographer_grpc/framework/client_writer.h"
-#include "cartographer_grpc/proto/map_builder_service.grpc.pb.h"
+#include "cartographer_grpc/framework/client.h"
+#include "cartographer_grpc/handlers/add_fixed_frame_pose_data_handler.h"
+#include "cartographer_grpc/handlers/add_imu_data_handler.h"
+#include "cartographer_grpc/handlers/add_landmark_data_handler.h"
+#include "cartographer_grpc/handlers/add_local_slam_result_data_handler.h"
+#include "cartographer_grpc/handlers/add_odometry_data_handler.h"
+#include "cartographer_grpc/handlers/add_rangefinder_data_handler.h"
+#include "cartographer_grpc/handlers/receive_local_slam_results_handler.h"
 #include "grpc++/grpc++.h"
 
 namespace cartographer_grpc {
@@ -57,27 +63,26 @@ class TrajectoryBuilderStub
           local_slam_result_data) override;
 
  private:
-  struct LocalSlamResultReader {
-    grpc::ClientContext client_context;
-    std::unique_ptr<grpc::ClientReader<proto::ReceiveLocalSlamResultsResponse>>
-        client_reader;
-    std::unique_ptr<std::thread> thread;
-  };
-
-  static void RunLocalSlamResultReader(
-      grpc::ClientReader<proto::ReceiveLocalSlamResultsResponse>* client_reader,
+  static void RunLocalSlamResultsReader(
+      framework::Client<handlers::ReceiveLocalSlamResultsHandler>*
+          client_reader,
       LocalSlamResultCallback local_slam_result_callback);
 
   std::shared_ptr<grpc::Channel> client_channel_;
   const int trajectory_id_;
-  std::unique_ptr<proto::MapBuilderService::Stub> stub_;
-  framework::ClientWriter<proto::AddRangefinderDataRequest> rangefinder_writer_;
-  framework::ClientWriter<proto::AddImuDataRequest> imu_writer_;
-  framework::ClientWriter<proto::AddOdometryDataRequest> odometry_writer_;
-  framework::ClientWriter<proto::AddFixedFramePoseDataRequest>
-      fixed_frame_writer_;
-  framework::ClientWriter<proto::AddLandmarkDataRequest> landmark_writer_;
-  LocalSlamResultReader local_slam_result_reader_;
+  std::unique_ptr<framework::Client<handlers::AddRangefinderDataHandler>>
+      add_rangefinder_client_;
+  std::unique_ptr<framework::Client<handlers::AddImuDataHandler>>
+      add_imu_client_;
+  std::unique_ptr<framework::Client<handlers::AddOdometryDataHandler>>
+      add_odometry_client_;
+  std::unique_ptr<framework::Client<handlers::AddFixedFramePoseDataHandler>>
+      add_fixed_frame_pose_client_;
+  std::unique_ptr<framework::Client<handlers::AddLandmarkDataHandler>>
+      add_landmark_client_;
+  framework::Client<handlers::ReceiveLocalSlamResultsHandler>
+      receive_local_slam_results_client_;
+  std::unique_ptr<std::thread> receive_local_slam_results_thread_;
 };
 
 }  // namespace mapping