Merge github.com:grpc/grpc into fix-proto-docker

63 files changed, 413 insertions, 306 deletions

diff --git a/src/core/census/log.c b/src/core/census/mlog.c
index 91b26941b8..a2cc46d3f2 100644
--- a/src/core/census/log.c
+++ b/src/core/census/mlog.c
@@ -88,7 +88,7 @@
 // include the name of the structure, which will be passed as the first
 // argument. E.g. cl_block_initialize() will initialize a cl_block.
 
-#include "src/core/census/log.h"
+#include "src/core/census/mlog.h"
 #include <grpc/support/alloc.h>
 #include <grpc/support/atm.h>
 #include <grpc/support/cpu.h>
diff --git a/src/core/census/log.h b/src/core/census/mlog.h
index 05daea066f..aaba9e1535 100644
--- a/src/core/census/log.h
+++ b/src/core/census/mlog.h
@@ -31,8 +31,10 @@
  *
  */
 
-#ifndef GRPC_INTERNAL_CORE_CENSUS_LOG_H
-#define GRPC_INTERNAL_CORE_CENSUS_LOG_H
+/* A very fast in-memory log, optimized for multiple writers. */
+
+#ifndef GRPC_INTERNAL_CORE_CENSUS_MLOG_H
+#define GRPC_INTERNAL_CORE_CENSUS_MLOG_H
 
 #include <grpc/support/port_platform.h>
 #include <stddef.h>
diff --git a/src/core/iomgr/iocp_windows.c b/src/core/iomgr/iocp_windows.c
index 759340e00e..807729708e 100644
--- a/src/core/iomgr/iocp_windows.c
+++ b/src/core/iomgr/iocp_windows.c
@@ -42,7 +42,7 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/thd.h>
 
-#include "src/core/iomgr/timer_internal.h"
+#include "src/core/iomgr/timer.h"
 #include "src/core/iomgr/iocp_windows.h"
 #include "src/core/iomgr/iomgr_internal.h"
 #include "src/core/iomgr/socket_windows.h"
diff --git a/src/core/iomgr/iomgr.c b/src/core/iomgr/iomgr.c
index 212ce5534d..04580150f3 100644
--- a/src/core/iomgr/iomgr.c
+++ b/src/core/iomgr/iomgr.c
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2015, Google Inc.
+ * Copyright 2015-2016, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -43,7 +43,7 @@
 #include <grpc/support/thd.h>
 
 #include "src/core/iomgr/iomgr_internal.h"
-#include "src/core/iomgr/timer_internal.h"
+#include "src/core/iomgr/timer.h"
 #include "src/core/support/string.h"
 
 static gpr_mu g_mu;
diff --git a/src/core/iomgr/pollset_posix.c b/src/core/iomgr/pollset_posix.c
index 19ee6650f0..1063727248 100644
--- a/src/core/iomgr/pollset_posix.c
+++ b/src/core/iomgr/pollset_posix.c
@@ -42,7 +42,6 @@
 #include <string.h>
 #include <unistd.h>
 
-#include "src/core/iomgr/timer_internal.h"
 #include "src/core/iomgr/fd_posix.h"
 #include "src/core/iomgr/iomgr_internal.h"
 #include "src/core/iomgr/socket_utils_posix.h"
@@ -274,16 +273,6 @@ void grpc_pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
     grpc_exec_ctx_enqueue_list(exec_ctx, &pollset->idle_jobs, NULL);
     goto done;
   }
-  /* Check alarms - these are a global resource so we just ping
-     each time through on every pollset.
-     May update deadline to ensure timely wakeups.
-     TODO(ctiller): can this work be localized? */
-  if (grpc_timer_check(exec_ctx, now, &deadline)) {
-    GPR_TIMER_MARK("grpc_pollset_work.alarm_triggered", 0);
-    gpr_mu_unlock(&pollset->mu);
-    locked = 0;
-    goto done;
-  }
   /* If we're shutting down then we don't execute any extended work */
   if (pollset->shutting_down) {
     GPR_TIMER_MARK("grpc_pollset_work.shutting_down", 0);
diff --git a/src/core/iomgr/pollset_posix.h b/src/core/iomgr/pollset_posix.h
index b34bb09426..5868b3fa21 100644
--- a/src/core/iomgr/pollset_posix.h
+++ b/src/core/iomgr/pollset_posix.h
@@ -142,6 +142,10 @@ int grpc_pollset_has_workers(grpc_pollset *pollset);
 void grpc_remove_fd_from_all_epoll_sets(int fd);
 
 /* override to allow tests to hook poll() usage */
+/* NOTE: Any changes to grpc_poll_function must take place when the gRPC
+   is certainly not doing any polling anywhere.
+   Otherwise, there might be a race between changing the variable and actually
+   doing a polling operation */
 typedef int (*grpc_poll_function_type)(struct pollfd *, nfds_t, int);
 extern grpc_poll_function_type grpc_poll_function;
 extern grpc_wakeup_fd grpc_global_wakeup_fd;
diff --git a/src/core/iomgr/pollset_windows.c b/src/core/iomgr/pollset_windows.c
index 02c6678363..35a956b27f 100644
--- a/src/core/iomgr/pollset_windows.c
+++ b/src/core/iomgr/pollset_windows.c
@@ -38,7 +38,6 @@
 #include <grpc/support/log.h>
 #include <grpc/support/thd.h>
 
-#include "src/core/iomgr/timer_internal.h"
 #include "src/core/iomgr/iomgr_internal.h"
 #include "src/core/iomgr/iocp_windows.h"
 #include "src/core/iomgr/pollset.h"
@@ -136,9 +135,6 @@ void grpc_pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
   worker->kicked = 0;
   worker->pollset = pollset;
   gpr_cv_init(&worker->cv);
-  if (grpc_timer_check(exec_ctx, now, &deadline)) {
-    goto done;
-  }
   if (!pollset->kicked_without_pollers && !pollset->shutting_down) {
     if (g_active_poller == NULL) {
       grpc_pollset_worker *next_worker;
diff --git a/src/core/iomgr/timer.c b/src/core/iomgr/timer.c
index a33d8f63a0..8379fffad0 100644
--- a/src/core/iomgr/timer.c
+++ b/src/core/iomgr/timer.c
@@ -34,7 +34,6 @@
 #include "src/core/iomgr/timer.h"
 
 #include "src/core/iomgr/timer_heap.h"
-#include "src/core/iomgr/timer_internal.h"
 #include "src/core/iomgr/time_averaged_stats.h"
 #include <grpc/support/log.h>
 #include <grpc/support/sync.h>
@@ -336,8 +335,8 @@ static int run_some_expired_timers(grpc_exec_ctx *exec_ctx, gpr_timespec now,
   return (int)n;
 }
 
-int grpc_timer_check(grpc_exec_ctx *exec_ctx, gpr_timespec now,
-                     gpr_timespec *next) {
+bool grpc_timer_check(grpc_exec_ctx *exec_ctx, gpr_timespec now,
+                      gpr_timespec *next) {
   GPR_ASSERT(now.clock_type == g_clock_type);
   return run_some_expired_timers(
       exec_ctx, now, next,
diff --git a/src/core/iomgr/timer.h b/src/core/iomgr/timer.h
index 720c9d5ab9..9ad1e92f42 100644
--- a/src/core/iomgr/timer.h
+++ b/src/core/iomgr/timer.h
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2015, Google Inc.
+ * Copyright 2015-2016, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -86,4 +86,24 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
    Requires:  cancel() must happen after add() on a given timer */
 void grpc_timer_cancel(grpc_exec_ctx *exec_ctx, grpc_timer *timer);
 
+/* iomgr internal api for dealing with timers */
+
+/* Check for timers to be run, and run them.
+   Return true if timer callbacks were executed.
+   Drops drop_mu if it is non-null before executing callbacks.
+   If next is non-null, TRY to update *next with the next running timer
+   IF that timer occurs before *next current value.
+   *next is never guaranteed to be updated on any given execution; however,
+   with high probability at least one thread in the system will see an update
+   at any time slice. */
+
+bool grpc_timer_check(grpc_exec_ctx *exec_ctx, gpr_timespec now,
+                      gpr_timespec *next);
+void grpc_timer_list_init(gpr_timespec now);
+void grpc_timer_list_shutdown(grpc_exec_ctx *exec_ctx);
+
+/* the following must be implemented by each iomgr implementation */
+
+void grpc_kick_poller(void);
+
 #endif /* GRPC_INTERNAL_CORE_IOMGR_TIMER_H */
diff --git a/src/core/iomgr/timer_internal.h b/src/core/iomgr/timer_internal.h
deleted file mode 100644
index f182e73764..0000000000
--- a/src/core/iomgr/timer_internal.h
+++ /dev/null
@@ -1,61 +0,0 @@
-/*
- *
- * Copyright 2015, Google Inc.
- * All rights reserved.
- *
- * 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.
- *
- */
-
-#ifndef GRPC_INTERNAL_CORE_IOMGR_TIMER_INTERNAL_H
-#define GRPC_INTERNAL_CORE_IOMGR_TIMER_INTERNAL_H
-
-#include "src/core/iomgr/exec_ctx.h"
-#include <grpc/support/sync.h>
-#include <grpc/support/time.h>
-
-/* iomgr internal api for dealing with timers */
-
-/* Check for timers to be run, and run them.
-   Return non zero if timer callbacks were executed.
-   Drops drop_mu if it is non-null before executing callbacks.
-   If next is non-null, TRY to update *next with the next running timer
-   IF that timer occurs before *next current value.
-   *next is never guaranteed to be updated on any given execution; however,
-   with high probability at least one thread in the system will see an update
-   at any time slice. */
-
-int grpc_timer_check(grpc_exec_ctx* exec_ctx, gpr_timespec now,
-                     gpr_timespec* next);
-void grpc_timer_list_init(gpr_timespec now);
-void grpc_timer_list_shutdown(grpc_exec_ctx* exec_ctx);
-
-/* the following must be implemented by each iomgr implementation */
-
-void grpc_kick_poller(void);
-
-#endif /* GRPC_INTERNAL_CORE_IOMGR_TIMER_INTERNAL_H */
diff --git a/src/core/surface/completion_queue.c b/src/core/surface/completion_queue.c
index 75298eb795..0a80680f02 100644
--- a/src/core/surface/completion_queue.c
+++ b/src/core/surface/completion_queue.c
@@ -323,7 +323,20 @@ grpc_event grpc_completion_queue_next(grpc_completion_queue *cc,
       break;
     }
     first_loop = 0;
-    grpc_pollset_work(&exec_ctx, &cc->pollset, &worker, now, deadline);
+    /* Check alarms - these are a global resource so we just ping
+       each time through on every pollset.
+       May update deadline to ensure timely wakeups.
+       TODO(ctiller): can this work be localized? */
+    gpr_timespec iteration_deadline = deadline;
+    if (grpc_timer_check(&exec_ctx, now, &iteration_deadline)) {
+      GPR_TIMER_MARK("alarm_triggered", 0);
+      gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset));
+      grpc_exec_ctx_flush(&exec_ctx);
+      gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset));
+    } else {
+      grpc_pollset_work(&exec_ctx, &cc->pollset, &worker, now,
+                        iteration_deadline);
+    }
   }
   GRPC_SURFACE_TRACE_RETURNED_EVENT(cc, &ret);
   GRPC_CQ_INTERNAL_UNREF(cc, "next");
@@ -427,7 +440,20 @@ grpc_event grpc_completion_queue_pluck(grpc_completion_queue *cc, void *tag,
       break;
     }
     first_loop = 0;
-    grpc_pollset_work(&exec_ctx, &cc->pollset, &worker, now, deadline);
+    /* Check alarms - these are a global resource so we just ping
+       each time through on every pollset.
+       May update deadline to ensure timely wakeups.
+       TODO(ctiller): can this work be localized? */
+    gpr_timespec iteration_deadline = deadline;
+    if (grpc_timer_check(&exec_ctx, now, &iteration_deadline)) {
+      GPR_TIMER_MARK("alarm_triggered", 0);
+      gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset));
+      grpc_exec_ctx_flush(&exec_ctx);
+      gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset));
+    } else {
+      grpc_pollset_work(&exec_ctx, &cc->pollset, &worker, now,
+                        iteration_deadline);
+    }
     del_plucker(cc, tag, &worker);
   }
 done:
diff --git a/src/core/transport/chttp2/internal.h b/src/core/transport/chttp2/internal.h
index 0e1e2c4265..d76d31be23 100644
--- a/src/core/transport/chttp2/internal.h
+++ b/src/core/transport/chttp2/internal.h
@@ -485,7 +485,8 @@ struct grpc_chttp2_stream {
 
 /** Someone is unlocking the transport mutex: check to see if writes
     are required, and schedule them if so */
-int grpc_chttp2_unlocking_check_writes(grpc_chttp2_transport_global *global,
+int grpc_chttp2_unlocking_check_writes(grpc_exec_ctx *exec_ctx,
+                                       grpc_chttp2_transport_global *global,
                                        grpc_chttp2_transport_writing *writing,
                                        int is_parsing);
 void grpc_chttp2_perform_writes(
@@ -568,8 +569,12 @@ void grpc_chttp2_list_add_writing_stalled_by_transport(
     grpc_chttp2_transport_writing *transport_writing,
     grpc_chttp2_stream_writing *stream_writing);
 void grpc_chttp2_list_flush_writing_stalled_by_transport(
-    grpc_chttp2_transport_writing *transport_writing, bool is_window_available);
+    grpc_exec_ctx *exec_ctx, grpc_chttp2_transport_writing *transport_writing,
+    bool is_window_available);
 
+void grpc_chttp2_list_add_stalled_by_transport(
+    grpc_chttp2_transport_writing *transport_writing,
+    grpc_chttp2_stream_writing *stream_writing);
 int grpc_chttp2_list_pop_stalled_by_transport(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_stream_global **stream_global);
diff --git a/src/core/transport/chttp2/stream_lists.c b/src/core/transport/chttp2/stream_lists.c
index 2f31a47cb3..b284c78818 100644
--- a/src/core/transport/chttp2/stream_lists.c
+++ b/src/core/transport/chttp2/stream_lists.c
@@ -316,13 +316,16 @@ int grpc_chttp2_list_pop_check_read_ops(
 void grpc_chttp2_list_add_writing_stalled_by_transport(
     grpc_chttp2_transport_writing *transport_writing,
     grpc_chttp2_stream_writing *stream_writing) {
-  stream_list_add(TRANSPORT_FROM_WRITING(transport_writing),
-                  STREAM_FROM_WRITING(stream_writing),
+  grpc_chttp2_stream *stream = STREAM_FROM_WRITING(stream_writing);
+  if (!stream->included[GRPC_CHTTP2_LIST_WRITING_STALLED_BY_TRANSPORT]) {
+    GRPC_CHTTP2_STREAM_REF(&stream->global, "chttp2_writing_stalled");
+  }
+  stream_list_add(TRANSPORT_FROM_WRITING(transport_writing), stream,
                   GRPC_CHTTP2_LIST_WRITING_STALLED_BY_TRANSPORT);
 }
 
 void grpc_chttp2_list_flush_writing_stalled_by_transport(
-    grpc_chttp2_transport_writing *transport_writing,
+    grpc_exec_ctx *exec_ctx, grpc_chttp2_transport_writing *transport_writing,
     bool is_window_available) {
   grpc_chttp2_stream *stream;
   grpc_chttp2_transport *transport = TRANSPORT_FROM_WRITING(transport_writing);
@@ -331,11 +334,22 @@ void grpc_chttp2_list_flush_writing_stalled_by_transport(
     if (is_window_available) {
       grpc_chttp2_list_add_writable_stream(&transport->global, &stream->global);
     } else {
-      stream_list_add(transport, stream, GRPC_CHTTP2_LIST_STALLED_BY_TRANSPORT);
+      grpc_chttp2_list_add_stalled_by_transport(transport_writing,
+                                                &stream->writing);
     }
+    GRPC_CHTTP2_STREAM_UNREF(exec_ctx, &stream->global,
+                             "chttp2_writing_stalled");
   }
 }
 
+void grpc_chttp2_list_add_stalled_by_transport(
+    grpc_chttp2_transport_writing *transport_writing,
+    grpc_chttp2_stream_writing *stream_writing) {
+  stream_list_add(TRANSPORT_FROM_WRITING(transport_writing),
+                  STREAM_FROM_WRITING(stream_writing),
+                  GRPC_CHTTP2_LIST_STALLED_BY_TRANSPORT);
+}
+
 int grpc_chttp2_list_pop_stalled_by_transport(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_stream_global **stream_global) {
diff --git a/src/core/transport/chttp2/writing.c b/src/core/transport/chttp2/writing.c
index cafecf1046..356fd8174a 100644
--- a/src/core/transport/chttp2/writing.c
+++ b/src/core/transport/chttp2/writing.c
@@ -44,7 +44,7 @@ static void finalize_outbuf(grpc_exec_ctx *exec_ctx,
                             grpc_chttp2_transport_writing *transport_writing);
 
 int grpc_chttp2_unlocking_check_writes(
-    grpc_chttp2_transport_global *transport_global,
+    grpc_exec_ctx *exec_ctx, grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_transport_writing *transport_writing, int is_parsing) {
   grpc_chttp2_stream_global *stream_global;
   grpc_chttp2_stream_writing *stream_writing;
@@ -76,8 +76,8 @@ int grpc_chttp2_unlocking_check_writes(
   GRPC_CHTTP2_FLOW_MOVE_TRANSPORT("write", transport_writing, outgoing_window,
                                   transport_global, outgoing_window);
   bool is_window_available = transport_writing->outgoing_window > 0;
-  grpc_chttp2_list_flush_writing_stalled_by_transport(transport_writing,
-                                                      is_window_available);
+  grpc_chttp2_list_flush_writing_stalled_by_transport(
+      exec_ctx, transport_writing, is_window_available);
 
   /* for each grpc_chttp2_stream that's become writable, frame it's data
      (according to available window sizes) and add to the output buffer */
@@ -133,8 +133,8 @@ int grpc_chttp2_unlocking_check_writes(
             GRPC_CHTTP2_STREAM_REF(stream_global, "chttp2_writing");
           }
         } else {
-          grpc_chttp2_list_add_writing_stalled_by_transport(transport_writing,
-                                                            stream_writing);
+          grpc_chttp2_list_add_stalled_by_transport(transport_writing,
+                                                    stream_writing);
         }
       }
       if (stream_global->send_trailing_metadata) {
diff --git a/src/core/transport/chttp2_transport.c b/src/core/transport/chttp2_transport.c
index 617d98875c..b9f511e946 100644
--- a/src/core/transport/chttp2_transport.c
+++ b/src/core/transport/chttp2_transport.c
@@ -598,7 +598,7 @@ static void lock(grpc_chttp2_transport *t) { gpr_mu_lock(&t->mu); }
 static void unlock(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t) {
   GPR_TIMER_BEGIN("unlock", 0);
   if (!t->writing_active && !t->closed &&
-      grpc_chttp2_unlocking_check_writes(&t->global, &t->writing,
+      grpc_chttp2_unlocking_check_writes(exec_ctx, &t->global, &t->writing,
                                          t->parsing_active)) {
     t->writing_active = 1;
     REF_TRANSPORT(t, "writing");
@@ -1019,6 +1019,11 @@ static void check_read_ops(grpc_exec_ctx *exec_ctx,
       stream_global->recv_initial_metadata_ready = NULL;
     }
     if (stream_global->recv_message_ready != NULL) {
+      while (stream_global->seen_error &&
+             (bs = grpc_chttp2_incoming_frame_queue_pop(
+                  &stream_global->incoming_frames)) != NULL) {
+        grpc_byte_stream_destroy(exec_ctx, bs);
+      }
       if (stream_global->incoming_frames.head != NULL) {
         *stream_global->recv_message = grpc_chttp2_incoming_frame_queue_pop(
             &stream_global->incoming_frames);
diff --git a/src/cpp/server/server.cc b/src/cpp/server/server.cc
index 0d31140924..6d31a608c8 100644
--- a/src/cpp/server/server.cc
+++ b/src/cpp/server/server.cc
@@ -272,27 +272,25 @@ class Server::SyncRequest GRPC_FINAL : public CompletionQueueTag {
   grpc_completion_queue* cq_;
 };
 
-static grpc_server* CreateServer(const ChannelArguments& args) {
-  grpc_channel_args channel_args;
-  args.SetChannelArgs(&channel_args);
-  return grpc_server_create(&channel_args, nullptr);
-}
-
 static internal::GrpcLibraryInitializer g_gli_initializer;
 Server::Server(ThreadPoolInterface* thread_pool, bool thread_pool_owned,
-               int max_message_size, const ChannelArguments& args)
+               int max_message_size, ChannelArguments* args)
     : max_message_size_(max_message_size),
       started_(false),
       shutdown_(false),
       num_running_cb_(0),
       sync_methods_(new std::list<SyncRequest>),
       has_generic_service_(false),
-      server_(CreateServer(args)),
+      server_(nullptr),
       thread_pool_(thread_pool),
       thread_pool_owned_(thread_pool_owned) {
   g_gli_initializer.summon();
   gpr_once_init(&g_once_init_callbacks, InitGlobalCallbacks);
   global_callbacks_ = g_callbacks;
+  global_callbacks_->UpdateArguments(args);
+  grpc_channel_args channel_args;
+  args->SetChannelArgs(&channel_args);
+  server_ = grpc_server_create(&channel_args, nullptr);
   grpc_server_register_completion_queue(server_, cq_.cq(), nullptr);
 }
 
diff --git a/src/cpp/server/server_builder.cc b/src/cpp/server/server_builder.cc
index c54cf6474f..134e5f1d5f 100644
--- a/src/cpp/server/server_builder.cc
+++ b/src/cpp/server/server_builder.cc
@@ -103,7 +103,7 @@ std::unique_ptr<Server> ServerBuilder::BuildAndStart() {
   args.SetInt(GRPC_COMPRESSION_ALGORITHM_STATE_ARG,
               compression_options_.enabled_algorithms_bitset);
   std::unique_ptr<Server> server(
-      new Server(thread_pool.release(), true, max_message_size_, args));
+      new Server(thread_pool.release(), true, max_message_size_, &args));
   for (auto cq = cqs_.begin(); cq != cqs_.end(); ++cq) {
     grpc_server_register_completion_queue(server->server_, (*cq)->cq(),
                                           nullptr);
diff --git a/src/csharp/Grpc.Auth/GoogleAuthInterceptors.cs b/src/csharp/Grpc.Auth/GoogleAuthInterceptors.cs
index f77e9c6573..1837f5c74b 100644
--- a/src/csharp/Grpc.Auth/GoogleAuthInterceptors.cs
+++ b/src/csharp/Grpc.Auth/GoogleAuthInterceptors.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -71,7 +71,7 @@ namespace Grpc.Auth
         /// <returns>The interceptor.</returns>
         public static AsyncAuthInterceptor FromAccessToken(string accessToken)
         {
-            Preconditions.CheckNotNull(accessToken);
+            GrpcPreconditions.CheckNotNull(accessToken);
             return new AsyncAuthInterceptor(async (context, metadata) =>
             {
                 metadata.Add(CreateBearerTokenHeader(accessToken));
diff --git a/src/csharp/Grpc.Core/AsyncAuthInterceptor.cs b/src/csharp/Grpc.Core/AsyncAuthInterceptor.cs
index 5c9ab04812..5ba06d6509 100644
--- a/src/csharp/Grpc.Core/AsyncAuthInterceptor.cs
+++ b/src/csharp/Grpc.Core/AsyncAuthInterceptor.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -61,8 +61,8 @@ namespace Grpc.Core
         /// </summary>
         public AuthInterceptorContext(string serviceUrl, string methodName)
         {
-            this.serviceUrl = Preconditions.CheckNotNull(serviceUrl);
-            this.methodName = Preconditions.CheckNotNull(methodName);
+            this.serviceUrl = GrpcPreconditions.CheckNotNull(serviceUrl);
+            this.methodName = GrpcPreconditions.CheckNotNull(methodName);
         }
 
         /// <summary>
diff --git a/src/csharp/Grpc.Core/CallCredentials.cs b/src/csharp/Grpc.Core/CallCredentials.cs
index a71c8904fe..7cd41d0480 100644
--- a/src/csharp/Grpc.Core/CallCredentials.cs
+++ b/src/csharp/Grpc.Core/CallCredentials.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -87,7 +87,7 @@ namespace Grpc.Core
         /// <param name="interceptor">authentication interceptor</param>
         public MetadataCredentials(AsyncAuthInterceptor interceptor)
         {
-            this.interceptor = Preconditions.CheckNotNull(interceptor);
+            this.interceptor = GrpcPreconditions.CheckNotNull(interceptor);
         }
 
         internal override CallCredentialsSafeHandle ToNativeCredentials()
@@ -111,7 +111,7 @@ namespace Grpc.Core
         /// <param name="credentials">credentials to compose</param>
         public CompositeCallCredentials(params CallCredentials[] credentials)
         {
-            Preconditions.CheckArgument(credentials.Length >= 2, "Composite credentials object can only be created from 2 or more credentials.");
+            GrpcPreconditions.CheckArgument(credentials.Length >= 2, "Composite credentials object can only be created from 2 or more credentials.");
             this.credentials = new List<CallCredentials>(credentials);
         }
 
diff --git a/src/csharp/Grpc.Core/CallInvocationDetails.cs b/src/csharp/Grpc.Core/CallInvocationDetails.cs
index 8228b8f317..52bfbe6edb 100644
--- a/src/csharp/Grpc.Core/CallInvocationDetails.cs
+++ b/src/csharp/Grpc.Core/CallInvocationDetails.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -85,11 +85,11 @@ namespace Grpc.Core
         /// <param name="options">Call options.</param>
         public CallInvocationDetails(Channel channel, string method, string host, Marshaller<TRequest> requestMarshaller, Marshaller<TResponse> responseMarshaller, CallOptions options)
         {
-            this.channel = Preconditions.CheckNotNull(channel, "channel");
-            this.method = Preconditions.CheckNotNull(method, "method");
+            this.channel = GrpcPreconditions.CheckNotNull(channel, "channel");
+            this.method = GrpcPreconditions.CheckNotNull(method, "method");
             this.host = host;
-            this.requestMarshaller = Preconditions.CheckNotNull(requestMarshaller, "requestMarshaller");
-            this.responseMarshaller = Preconditions.CheckNotNull(responseMarshaller, "responseMarshaller");
+            this.requestMarshaller = GrpcPreconditions.CheckNotNull(requestMarshaller, "requestMarshaller");
+            this.responseMarshaller = GrpcPreconditions.CheckNotNull(responseMarshaller, "responseMarshaller");
             this.options = options;
         }
 
diff --git a/src/csharp/Grpc.Core/CallOptions.cs b/src/csharp/Grpc.Core/CallOptions.cs
index 1fda80cb90..7bd95d4ba8 100644
--- a/src/csharp/Grpc.Core/CallOptions.cs
+++ b/src/csharp/Grpc.Core/CallOptions.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -176,13 +176,13 @@ namespace Grpc.Core
             {
                 if (propagationToken.Options.IsPropagateDeadline)
                 {
-                    Preconditions.CheckArgument(!newOptions.deadline.HasValue,
+                    GrpcPreconditions.CheckArgument(!newOptions.deadline.HasValue,
                         "Cannot propagate deadline from parent call. The deadline has already been set explicitly.");
                     newOptions.deadline = propagationToken.ParentDeadline;
                 }
                 if (propagationToken.Options.IsPropagateCancellation)
                 {
-                    Preconditions.CheckArgument(!newOptions.cancellationToken.CanBeCanceled,
+                    GrpcPreconditions.CheckArgument(!newOptions.cancellationToken.CanBeCanceled,
                         "Cannot propagate cancellation token from parent call. The cancellation token has already been set to a non-default value.");
                     newOptions.cancellationToken = propagationToken.ParentCancellationToken;
                 }
diff --git a/src/csharp/Grpc.Core/Channel.cs b/src/csharp/Grpc.Core/Channel.cs
index d8d43c7998..d7a482d86f 100644
--- a/src/csharp/Grpc.Core/Channel.cs
+++ b/src/csharp/Grpc.Core/Channel.cs
@@ -1,5 +1,5 @@
 #region Copyright notice and license
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -68,7 +68,7 @@ namespace Grpc.Core
         /// <param name="options">Channel options.</param>
         public Channel(string target, ChannelCredentials credentials, IEnumerable<ChannelOption> options = null)
         {
-            this.target = Preconditions.CheckNotNull(target, "target");
+            this.target = GrpcPreconditions.CheckNotNull(target, "target");
             this.options = CreateOptionsDictionary(options);
             EnsureUserAgentChannelOption(this.options);
             this.environment = GrpcEnvironment.AddRef();
@@ -117,7 +117,7 @@ namespace Grpc.Core
         /// </summary>
         public Task WaitForStateChangedAsync(ChannelState lastObservedState, DateTime? deadline = null)
         {
-            Preconditions.CheckArgument(lastObservedState != ChannelState.FatalFailure,
+            GrpcPreconditions.CheckArgument(lastObservedState != ChannelState.FatalFailure,
                 "FatalFailure is a terminal state. No further state changes can occur.");
             var tcs = new TaskCompletionSource<object>();
             var deadlineTimespec = deadline.HasValue ? Timespec.FromDateTime(deadline.Value) : Timespec.InfFuture;
@@ -184,7 +184,7 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!shutdownRequested);
+                GrpcPreconditions.CheckState(!shutdownRequested);
                 shutdownRequested = true;
             }
 
@@ -221,7 +221,7 @@ namespace Grpc.Core
 
             bool success = false;
             handle.DangerousAddRef(ref success);
-            Preconditions.CheckState(success);
+            GrpcPreconditions.CheckState(success);
         }
 
         internal void RemoveCallReference(object call)
diff --git a/src/csharp/Grpc.Core/ChannelCredentials.cs b/src/csharp/Grpc.Core/ChannelCredentials.cs
index 5d96958e7c..03cda28400 100644
--- a/src/csharp/Grpc.Core/ChannelCredentials.cs
+++ b/src/csharp/Grpc.Core/ChannelCredentials.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -183,9 +183,9 @@ namespace Grpc.Core
         /// <param name="callCredentials">channelCredentials to compose</param>
         public CompositeChannelCredentials(ChannelCredentials channelCredentials, CallCredentials callCredentials)
         {
-            this.channelCredentials = Preconditions.CheckNotNull(channelCredentials);
-            this.callCredentials = Preconditions.CheckNotNull(callCredentials);
-            Preconditions.CheckArgument(channelCredentials.IsComposable, "Supplied channel credentials do not allow composition.");
+            this.channelCredentials = GrpcPreconditions.CheckNotNull(channelCredentials);
+            this.callCredentials = GrpcPreconditions.CheckNotNull(callCredentials);
+            GrpcPreconditions.CheckArgument(channelCredentials.IsComposable, "Supplied channel credentials do not allow composition.");
         }
 
         internal override ChannelCredentialsSafeHandle ToNativeCredentials()
diff --git a/src/csharp/Grpc.Core/ChannelOptions.cs b/src/csharp/Grpc.Core/ChannelOptions.cs
index d70673cf78..65e15e21e9 100644
--- a/src/csharp/Grpc.Core/ChannelOptions.cs
+++ b/src/csharp/Grpc.Core/ChannelOptions.cs
@@ -1,5 +1,5 @@
 #region Copyright notice and license
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -73,8 +73,8 @@ namespace Grpc.Core
         public ChannelOption(string name, string stringValue)
         {
             this.type = OptionType.String;
-            this.name = Preconditions.CheckNotNull(name, "name");
-            this.stringValue = Preconditions.CheckNotNull(stringValue, "stringValue");
+            this.name = GrpcPreconditions.CheckNotNull(name, "name");
+            this.stringValue = GrpcPreconditions.CheckNotNull(stringValue, "stringValue");
         }
 
         /// <summary>
@@ -85,7 +85,7 @@ namespace Grpc.Core
         public ChannelOption(string name, int intValue)
         {
             this.type = OptionType.Integer;
-            this.name = Preconditions.CheckNotNull(name, "name");
+            this.name = GrpcPreconditions.CheckNotNull(name, "name");
             this.intValue = intValue;
         }
 
@@ -118,7 +118,7 @@ namespace Grpc.Core
         {
             get
             {
-                Preconditions.CheckState(type == OptionType.Integer);
+                GrpcPreconditions.CheckState(type == OptionType.Integer);
                 return intValue;
             }
         }
@@ -130,7 +130,7 @@ namespace Grpc.Core
         {
             get
             {
-                Preconditions.CheckState(type == OptionType.String);
+                GrpcPreconditions.CheckState(type == OptionType.String);
                 return stringValue;
             }
         }
diff --git a/src/csharp/Grpc.Core/ContextPropagationToken.cs b/src/csharp/Grpc.Core/ContextPropagationToken.cs
index 1d899b97fd..c0f638f837 100644
--- a/src/csharp/Grpc.Core/ContextPropagationToken.cs
+++ b/src/csharp/Grpc.Core/ContextPropagationToken.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -68,7 +68,7 @@ namespace Grpc.Core
 
         internal ContextPropagationToken(CallSafeHandle parentCall, DateTime deadline, CancellationToken cancellationToken, ContextPropagationOptions options)
         {
-            this.parentCall = Preconditions.CheckNotNull(parentCall);
+            this.parentCall = GrpcPreconditions.CheckNotNull(parentCall);
             this.deadline = deadline;
             this.cancellationToken = cancellationToken;
             this.options = options ?? ContextPropagationOptions.Default;
diff --git a/src/csharp/Grpc.Core/Grpc.Core.csproj b/src/csharp/Grpc.Core/Grpc.Core.csproj
index 8d7d2cae0d..3189835ccd 100644
--- a/src/csharp/Grpc.Core/Grpc.Core.csproj
+++ b/src/csharp/Grpc.Core/Grpc.Core.csproj
@@ -39,8 +39,7 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="System" />
-    <Reference Include="System.Interactive.Async, Version=1.2.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
+    <Reference Include="System.Interactive.Async">
       <HintPath>..\packages\Ix-Async.1.2.5\lib\net45\System.Interactive.Async.dll</HintPath>
     </Reference>
   </ItemGroup>
@@ -91,7 +90,6 @@
     <Compile Include="Internal\AsyncCallBase.cs" />
     <Compile Include="Internal\AsyncCallServer.cs" />
     <Compile Include="Internal\AsyncCall.cs" />
-    <Compile Include="Utils\Preconditions.cs" />
     <Compile Include="Internal\ServerCredentialsSafeHandle.cs" />
     <Compile Include="ServerCredentials.cs" />
     <Compile Include="Metadata.cs" />
@@ -130,6 +128,7 @@
     <Compile Include="Profiling\IProfiler.cs" />
     <Compile Include="Profiling\Profilers.cs" />
     <Compile Include="Internal\DefaultSslRootsOverride.cs" />
+    <Compile Include="Utils\GrpcPreconditions.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="Grpc.Core.nuspec" />
diff --git a/src/csharp/Grpc.Core/GrpcEnvironment.cs b/src/csharp/Grpc.Core/GrpcEnvironment.cs
index f3aa3d79de..86b37b8660 100644
--- a/src/csharp/Grpc.Core/GrpcEnvironment.cs
+++ b/src/csharp/Grpc.Core/GrpcEnvironment.cs
@@ -83,7 +83,7 @@ namespace Grpc.Core
         {
             lock (staticLock)
             {
-                Preconditions.CheckState(refCount > 0);
+                GrpcPreconditions.CheckState(refCount > 0);
                 refCount--;
                 if (refCount == 0)
                 {
@@ -118,7 +118,7 @@ namespace Grpc.Core
         /// </summary>
         public static void SetLogger(ILogger customLogger)
         {
-            Preconditions.CheckNotNull(customLogger, "customLogger");
+            GrpcPreconditions.CheckNotNull(customLogger, "customLogger");
             logger = customLogger;
         }
 
diff --git a/src/csharp/Grpc.Core/Internal/AsyncCall.cs b/src/csharp/Grpc.Core/Internal/AsyncCall.cs
index 7dc4490281..2caba260b3 100644
--- a/src/csharp/Grpc.Core/Internal/AsyncCall.cs
+++ b/src/csharp/Grpc.Core/Internal/AsyncCall.cs
@@ -99,7 +99,7 @@ namespace Grpc.Core.Internal
 
                 lock (myLock)
                 {
-                    Preconditions.CheckState(!started);
+                    GrpcPreconditions.CheckState(!started);
                     started = true;
                     Initialize(cq);
 
@@ -141,7 +141,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!started);
+                GrpcPreconditions.CheckState(!started);
                 started = true;
 
                 Initialize(environment.CompletionQueue);
@@ -168,7 +168,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!started);
+                GrpcPreconditions.CheckState(!started);
                 started = true;
 
                 Initialize(environment.CompletionQueue);
@@ -192,7 +192,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!started);
+                GrpcPreconditions.CheckState(!started);
                 started = true;
 
                 Initialize(environment.CompletionQueue);
@@ -217,7 +217,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!started);
+                GrpcPreconditions.CheckState(!started);
                 started = true;
 
                 Initialize(environment.CompletionQueue);
@@ -257,7 +257,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
                 CheckSendingAllowed();
 
                 call.StartSendCloseFromClient(HandleHalfclosed);
@@ -297,7 +297,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(finishedStatus.HasValue, "Status can only be accessed once the call has finished.");
+                GrpcPreconditions.CheckState(finishedStatus.HasValue, "Status can only be accessed once the call has finished.");
                 return finishedStatus.Value.Status;
             }
         }
@@ -310,7 +310,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(finishedStatus.HasValue, "Trailers can only be accessed once the call has finished.");
+                GrpcPreconditions.CheckState(finishedStatus.HasValue, "Trailers can only be accessed once the call has finished.");
                 return finishedStatus.Value.Trailers;
             }
         }
diff --git a/src/csharp/Grpc.Core/Internal/AsyncCallBase.cs b/src/csharp/Grpc.Core/Internal/AsyncCallBase.cs
index 81a9a40fcc..45d4c3e078 100644
--- a/src/csharp/Grpc.Core/Internal/AsyncCallBase.cs
+++ b/src/csharp/Grpc.Core/Internal/AsyncCallBase.cs
@@ -79,9 +79,9 @@ namespace Grpc.Core.Internal
 
         public AsyncCallBase(Func<TWrite, byte[]> serializer, Func<byte[], TRead> deserializer, GrpcEnvironment environment)
         {
-            this.serializer = Preconditions.CheckNotNull(serializer);
-            this.deserializer = Preconditions.CheckNotNull(deserializer);
-            this.environment = Preconditions.CheckNotNull(environment);
+            this.serializer = GrpcPreconditions.CheckNotNull(serializer);
+            this.deserializer = GrpcPreconditions.CheckNotNull(deserializer);
+            this.environment = GrpcPreconditions.CheckNotNull(environment);
         }
 
         /// <summary>
@@ -91,7 +91,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(started);
+                GrpcPreconditions.CheckState(started);
                 cancelRequested = true;
 
                 if (!disposed)
@@ -135,7 +135,7 @@ namespace Grpc.Core.Internal
 
             lock (myLock)
             {
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
                 CheckSendingAllowed();
 
                 call.StartSendMessage(HandleSendFinished, payload, writeFlags, !initialMetadataSent);
@@ -154,7 +154,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
                 CheckReadingAllowed();
 
                 call.StartReceiveMessage(HandleReadFinished);
@@ -204,22 +204,22 @@ namespace Grpc.Core.Internal
 
         protected void CheckSendingAllowed()
         {
-            Preconditions.CheckState(started);
+            GrpcPreconditions.CheckState(started);
             CheckNotCancelled();
-            Preconditions.CheckState(!disposed);
+            GrpcPreconditions.CheckState(!disposed);
 
-            Preconditions.CheckState(!halfcloseRequested, "Already halfclosed.");
-            Preconditions.CheckState(!finished, "Already finished.");
-            Preconditions.CheckState(sendCompletionDelegate == null, "Only one write can be pending at a time");
+            GrpcPreconditions.CheckState(!halfcloseRequested, "Already halfclosed.");
+            GrpcPreconditions.CheckState(!finished, "Already finished.");
+            GrpcPreconditions.CheckState(sendCompletionDelegate == null, "Only one write can be pending at a time");
         }
 
         protected virtual void CheckReadingAllowed()
         {
-            Preconditions.CheckState(started);
-            Preconditions.CheckState(!disposed);
+            GrpcPreconditions.CheckState(started);
+            GrpcPreconditions.CheckState(!disposed);
 
-            Preconditions.CheckState(!readingDone, "Stream has already been closed.");
-            Preconditions.CheckState(readCompletionDelegate == null, "Only one read can be pending at a time");
+            GrpcPreconditions.CheckState(!readingDone, "Stream has already been closed.");
+            GrpcPreconditions.CheckState(readCompletionDelegate == null, "Only one read can be pending at a time");
         }
 
         protected void CheckNotCancelled()
diff --git a/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs b/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
index 6752d3fab3..b72cbd795f 100644
--- a/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
+++ b/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
@@ -53,7 +53,7 @@ namespace Grpc.Core.Internal
 
         public AsyncCallServer(Func<TResponse, byte[]> serializer, Func<byte[], TRequest> deserializer, GrpcEnvironment environment, Server server) : base(serializer, deserializer, environment)
         {
-            this.server = Preconditions.CheckNotNull(server);
+            this.server = GrpcPreconditions.CheckNotNull(server);
         }
 
         public void Initialize(CallSafeHandle call)
@@ -71,7 +71,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(call);
+                GrpcPreconditions.CheckNotNull(call);
 
                 started = true;
 
@@ -108,14 +108,14 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(headers, "metadata");
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(headers, "metadata");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
 
-                Preconditions.CheckState(!initialMetadataSent, "Response headers can only be sent once per call.");
-                Preconditions.CheckState(streamingWritesCounter == 0, "Response headers can only be sent before the first write starts.");
+                GrpcPreconditions.CheckState(!initialMetadataSent, "Response headers can only be sent once per call.");
+                GrpcPreconditions.CheckState(streamingWritesCounter == 0, "Response headers can only be sent before the first write starts.");
                 CheckSendingAllowed();
 
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
 
                 using (var metadataArray = MetadataArraySafeHandle.Create(headers))
                 {
@@ -136,7 +136,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
                 CheckSendingAllowed();
 
                 using (var metadataArray = MetadataArraySafeHandle.Create(trailers))
@@ -177,7 +177,7 @@ namespace Grpc.Core.Internal
         protected override void CheckReadingAllowed()
         {
             base.CheckReadingAllowed();
-            Preconditions.CheckArgument(!cancelRequested);
+            GrpcPreconditions.CheckArgument(!cancelRequested);
         }
 
         protected override void OnAfterReleaseResources()
diff --git a/src/csharp/Grpc.Core/Internal/CompletionQueueSafeHandle.cs b/src/csharp/Grpc.Core/Internal/CompletionQueueSafeHandle.cs
index 9d7a990c42..5c75b52e23 100644
--- a/src/csharp/Grpc.Core/Internal/CompletionQueueSafeHandle.cs
+++ b/src/csharp/Grpc.Core/Internal/CompletionQueueSafeHandle.cs
@@ -101,7 +101,7 @@ namespace Grpc.Core.Internal
         {
             bool success = false;
             shutdownRefcount.IncrementIfNonzero(ref success);
-            Preconditions.CheckState(success, "Shutdown has already been called");
+            GrpcPreconditions.CheckState(success, "Shutdown has already been called");
         }
 
         private void EndOp()
diff --git a/src/csharp/Grpc.Core/Internal/CompletionRegistry.cs b/src/csharp/Grpc.Core/Internal/CompletionRegistry.cs
index 2796c959a3..3a293e1626 100644
--- a/src/csharp/Grpc.Core/Internal/CompletionRegistry.cs
+++ b/src/csharp/Grpc.Core/Internal/CompletionRegistry.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -59,7 +59,7 @@ namespace Grpc.Core.Internal
         public void Register(IntPtr key, OpCompletionDelegate callback)
         {
             environment.DebugStats.PendingBatchCompletions.Increment();
-            Preconditions.CheckState(dict.TryAdd(key, callback));
+            GrpcPreconditions.CheckState(dict.TryAdd(key, callback));
         }
 
         public void RegisterBatchCompletion(BatchContextSafeHandle ctx, BatchCompletionDelegate callback)
@@ -71,7 +71,7 @@ namespace Grpc.Core.Internal
         public OpCompletionDelegate Extract(IntPtr key)
         {
             OpCompletionDelegate value;
-            Preconditions.CheckState(dict.TryRemove(key, out value));
+            GrpcPreconditions.CheckState(dict.TryRemove(key, out value));
             environment.DebugStats.PendingBatchCompletions.Decrement();
             return value;
         }
diff --git a/src/csharp/Grpc.Core/Internal/Enums.cs b/src/csharp/Grpc.Core/Internal/Enums.cs
index b0eab2001b..098e7c0e99 100644
--- a/src/csharp/Grpc.Core/Internal/Enums.cs
+++ b/src/csharp/Grpc.Core/Internal/Enums.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -72,7 +72,7 @@ namespace Grpc.Core.Internal
         /// </summary>
         public static void CheckOk(this GRPCCallError callError)
         {
-            Preconditions.CheckState(callError == GRPCCallError.OK, "Call error: " + callError);
+            GrpcPreconditions.CheckState(callError == GRPCCallError.OK, "Call error: " + callError);
         }
     }
 
diff --git a/src/csharp/Grpc.Core/Internal/NativeMetadataCredentialsPlugin.cs b/src/csharp/Grpc.Core/Internal/NativeMetadataCredentialsPlugin.cs
index 36b865c09c..e810ffcdd0 100644
--- a/src/csharp/Grpc.Core/Internal/NativeMetadataCredentialsPlugin.cs
+++ b/src/csharp/Grpc.Core/Internal/NativeMetadataCredentialsPlugin.cs
@@ -53,7 +53,7 @@ namespace Grpc.Core.Internal
 
         public NativeMetadataCredentialsPlugin(AsyncAuthInterceptor interceptor)
         {
-            this.interceptor = Preconditions.CheckNotNull(interceptor, "interceptor");
+            this.interceptor = GrpcPreconditions.CheckNotNull(interceptor, "interceptor");
             this.nativeInterceptor = NativeMetadataInterceptorHandler;
 
             // Make sure the callback doesn't get garbage collected until it is destroyed.
diff --git a/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs b/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
index de66759b94..ccf144de2d 100644
--- a/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
+++ b/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -78,10 +78,10 @@ namespace Grpc.Core.Internal
             var context = HandlerUtils.NewContext(newRpc, asyncCall.Peer, responseStream, asyncCall.CancellationToken);
             try
             {
-                Preconditions.CheckArgument(await requestStream.MoveNext().ConfigureAwait(false));
+                GrpcPreconditions.CheckArgument(await requestStream.MoveNext().ConfigureAwait(false));
                 var request = requestStream.Current;
                 // TODO(jtattermusch): we need to read the full stream so that native callhandle gets deallocated.
-                Preconditions.CheckArgument(!await requestStream.MoveNext().ConfigureAwait(false));
+                GrpcPreconditions.CheckArgument(!await requestStream.MoveNext().ConfigureAwait(false));
                 var result = await handler(request, context).ConfigureAwait(false);
                 status = context.Status;
                 await responseStream.WriteAsync(result).ConfigureAwait(false);
@@ -134,10 +134,10 @@ namespace Grpc.Core.Internal
             var context = HandlerUtils.NewContext(newRpc, asyncCall.Peer, responseStream, asyncCall.CancellationToken);
             try
             {
-                Preconditions.CheckArgument(await requestStream.MoveNext().ConfigureAwait(false));
+                GrpcPreconditions.CheckArgument(await requestStream.MoveNext().ConfigureAwait(false));
                 var request = requestStream.Current;
                 // TODO(jtattermusch): we need to read the full stream so that native callhandle gets deallocated.
-                Preconditions.CheckArgument(!await requestStream.MoveNext().ConfigureAwait(false));
+                GrpcPreconditions.CheckArgument(!await requestStream.MoveNext().ConfigureAwait(false));
                 await handler(request, responseStream, context).ConfigureAwait(false);
                 status = context.Status;
             }
diff --git a/src/csharp/Grpc.Core/Internal/ServerCredentialsSafeHandle.cs b/src/csharp/Grpc.Core/Internal/ServerCredentialsSafeHandle.cs
index a1d080c7f1..a50f357990 100644
--- a/src/csharp/Grpc.Core/Internal/ServerCredentialsSafeHandle.cs
+++ b/src/csharp/Grpc.Core/Internal/ServerCredentialsSafeHandle.cs
@@ -49,7 +49,7 @@ namespace Grpc.Core.Internal
 
         public static ServerCredentialsSafeHandle CreateSslCredentials(string pemRootCerts, string[] keyCertPairCertChainArray, string[] keyCertPairPrivateKeyArray, bool forceClientAuth)
         {
-            Preconditions.CheckArgument(keyCertPairCertChainArray.Length == keyCertPairPrivateKeyArray.Length);
+            GrpcPreconditions.CheckArgument(keyCertPairCertChainArray.Length == keyCertPairPrivateKeyArray.Length);
             return Native.grpcsharp_ssl_server_credentials_create(pemRootCerts,
                                                                   keyCertPairCertChainArray, keyCertPairPrivateKeyArray,
                                                                   new UIntPtr((ulong)keyCertPairCertChainArray.Length),
diff --git a/src/csharp/Grpc.Core/Internal/Timespec.cs b/src/csharp/Grpc.Core/Internal/Timespec.cs
index 148d877da5..754be4e035 100644
--- a/src/csharp/Grpc.Core/Internal/Timespec.cs
+++ b/src/csharp/Grpc.Core/Internal/Timespec.cs
@@ -141,8 +141,8 @@ namespace Grpc.Core.Internal
         /// </summary>
         public DateTime ToDateTime()
         {
-            Preconditions.CheckState(tv_nsec >= 0 && tv_nsec < NanosPerSecond);
-            Preconditions.CheckState(clock_type == GPRClockType.Realtime);
+            GrpcPreconditions.CheckState(tv_nsec >= 0 && tv_nsec < NanosPerSecond);
+            GrpcPreconditions.CheckState(clock_type == GPRClockType.Realtime);
 
             // fast path for InfFuture
             if (this.Equals(InfFuture))
@@ -195,7 +195,7 @@ namespace Grpc.Core.Internal
                 return Timespec.InfPast;
             }
 
-            Preconditions.CheckArgument(dateTime.Kind == DateTimeKind.Utc, "dateTime needs of kind DateTimeKind.Utc or be equal to DateTime.MaxValue or DateTime.MinValue.");
+            GrpcPreconditions.CheckArgument(dateTime.Kind == DateTimeKind.Utc, "dateTime needs of kind DateTimeKind.Utc or be equal to DateTime.MaxValue or DateTime.MinValue.");
 
             try
             {
diff --git a/src/csharp/Grpc.Core/Internal/UnmanagedLibrary.cs b/src/csharp/Grpc.Core/Internal/UnmanagedLibrary.cs
index 95a8797e3e..e763c15025 100644
--- a/src/csharp/Grpc.Core/Internal/UnmanagedLibrary.cs
+++ b/src/csharp/Grpc.Core/Internal/UnmanagedLibrary.cs
@@ -65,7 +65,7 @@ namespace Grpc.Core.Internal
 
         public UnmanagedLibrary(string libraryPath)
         {
-            this.libraryPath = Preconditions.CheckNotNull(libraryPath);
+            this.libraryPath = GrpcPreconditions.CheckNotNull(libraryPath);
 
             if (!File.Exists(this.libraryPath))
             {
diff --git a/src/csharp/Grpc.Core/KeyCertificatePair.cs b/src/csharp/Grpc.Core/KeyCertificatePair.cs
index 6f691975e9..0fb6817986 100644
--- a/src/csharp/Grpc.Core/KeyCertificatePair.cs
+++ b/src/csharp/Grpc.Core/KeyCertificatePair.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -54,8 +54,8 @@ namespace Grpc.Core
         /// <param name="privateKey">PEM encoded private key.</param>
         public KeyCertificatePair(string certificateChain, string privateKey)
         {
-            this.certificateChain = Preconditions.CheckNotNull(certificateChain, "certificateChain");
-            this.privateKey = Preconditions.CheckNotNull(privateKey, "privateKey");
+            this.certificateChain = GrpcPreconditions.CheckNotNull(certificateChain, "certificateChain");
+            this.privateKey = GrpcPreconditions.CheckNotNull(privateKey, "privateKey");
         }
 
         /// <summary>
diff --git a/src/csharp/Grpc.Core/Marshaller.cs b/src/csharp/Grpc.Core/Marshaller.cs
index 3493d2d38f..5847248c1a 100644
--- a/src/csharp/Grpc.Core/Marshaller.cs
+++ b/src/csharp/Grpc.Core/Marshaller.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -51,8 +51,8 @@ namespace Grpc.Core
         /// <param name="deserializer">Function that will be used to deserialize messages.</param>
         public Marshaller(Func<T, byte[]> serializer, Func<byte[], T> deserializer)
         {
-            this.serializer = Preconditions.CheckNotNull(serializer, "serializer");
-            this.deserializer = Preconditions.CheckNotNull(deserializer, "deserializer");
+            this.serializer = GrpcPreconditions.CheckNotNull(serializer, "serializer");
+            this.deserializer = GrpcPreconditions.CheckNotNull(deserializer, "deserializer");
         }
 
         /// <summary>
diff --git a/src/csharp/Grpc.Core/Metadata.cs b/src/csharp/Grpc.Core/Metadata.cs
index 21bdf4f114..aa22f840d6 100644
--- a/src/csharp/Grpc.Core/Metadata.cs
+++ b/src/csharp/Grpc.Core/Metadata.cs
@@ -1,5 +1,5 @@
 #region Copyright notice and license
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -179,7 +179,7 @@ namespace Grpc.Core
 
         private void CheckWriteable()
         {
-            Preconditions.CheckState(!readOnly, "Object is read only");
+            GrpcPreconditions.CheckState(!readOnly, "Object is read only");
         }
 
         #endregion
@@ -211,10 +211,10 @@ namespace Grpc.Core
             public Entry(string key, byte[] valueBytes)
             {
                 this.key = NormalizeKey(key);
-                Preconditions.CheckArgument(this.key.EndsWith(BinaryHeaderSuffix),
+                GrpcPreconditions.CheckArgument(this.key.EndsWith(BinaryHeaderSuffix),
                     "Key for binary valued metadata entry needs to have suffix indicating binary value.");
                 this.value = null;
-                Preconditions.CheckNotNull(valueBytes, "valueBytes");
+                GrpcPreconditions.CheckNotNull(valueBytes, "valueBytes");
                 this.valueBytes = new byte[valueBytes.Length];
                 Buffer.BlockCopy(valueBytes, 0, this.valueBytes, 0, valueBytes.Length);  // defensive copy to guarantee immutability
             }
@@ -227,9 +227,9 @@ namespace Grpc.Core
             public Entry(string key, string value)
             {
                 this.key = NormalizeKey(key);
-                Preconditions.CheckArgument(!this.key.EndsWith(BinaryHeaderSuffix),
+                GrpcPreconditions.CheckArgument(!this.key.EndsWith(BinaryHeaderSuffix),
                     "Key for ASCII valued metadata entry cannot have suffix indicating binary value.");
-                this.value = Preconditions.CheckNotNull(value, "value");
+                this.value = GrpcPreconditions.CheckNotNull(value, "value");
                 this.valueBytes = null;
             }
 
@@ -270,7 +270,7 @@ namespace Grpc.Core
             {
                 get
                 {
-                    Preconditions.CheckState(!IsBinary, "Cannot access string value of a binary metadata entry");
+                    GrpcPreconditions.CheckState(!IsBinary, "Cannot access string value of a binary metadata entry");
                     return value ?? Encoding.GetString(valueBytes);
                 }
             }
@@ -323,8 +323,8 @@ namespace Grpc.Core
 
             private static string NormalizeKey(string key)
             {
-                var normalized = Preconditions.CheckNotNull(key, "key").ToLower(CultureInfo.InvariantCulture);
-                Preconditions.CheckArgument(ValidKeyRegex.IsMatch(normalized), 
+                var normalized = GrpcPreconditions.CheckNotNull(key, "key").ToLower(CultureInfo.InvariantCulture);
+                GrpcPreconditions.CheckArgument(ValidKeyRegex.IsMatch(normalized), 
                     "Metadata entry key not valid. Keys can only contain lowercase alphanumeric characters, underscores and hyphens.");
                 return normalized;
             }
diff --git a/src/csharp/Grpc.Core/Method.cs b/src/csharp/Grpc.Core/Method.cs
index 99162a7d5d..3870076f7f 100644
--- a/src/csharp/Grpc.Core/Method.cs
+++ b/src/csharp/Grpc.Core/Method.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -106,10 +106,10 @@ namespace Grpc.Core
         public Method(MethodType type, string serviceName, string name, Marshaller<TRequest> requestMarshaller, Marshaller<TResponse> responseMarshaller)
         {
             this.type = type;
-            this.serviceName = Preconditions.CheckNotNull(serviceName, "serviceName");
-            this.name = Preconditions.CheckNotNull(name, "name");
-            this.requestMarshaller = Preconditions.CheckNotNull(requestMarshaller, "requestMarshaller");
-            this.responseMarshaller = Preconditions.CheckNotNull(responseMarshaller, "responseMarshaller");
+            this.serviceName = GrpcPreconditions.CheckNotNull(serviceName, "serviceName");
+            this.name = GrpcPreconditions.CheckNotNull(name, "name");
+            this.requestMarshaller = GrpcPreconditions.CheckNotNull(requestMarshaller, "requestMarshaller");
+            this.responseMarshaller = GrpcPreconditions.CheckNotNull(responseMarshaller, "responseMarshaller");
             this.fullName = GetFullName(serviceName, name);
         }
 
diff --git a/src/csharp/Grpc.Core/Server.cs b/src/csharp/Grpc.Core/Server.cs
index d120f95fdf..5d0fc6b1f0 100644
--- a/src/csharp/Grpc.Core/Server.cs
+++ b/src/csharp/Grpc.Core/Server.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -125,7 +125,7 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!startRequested);
+                GrpcPreconditions.CheckState(!startRequested);
                 startRequested = true;
                 
                 handle.Start();
@@ -142,8 +142,8 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckState(startRequested);
-                Preconditions.CheckState(!shutdownRequested);
+                GrpcPreconditions.CheckState(startRequested);
+                GrpcPreconditions.CheckState(!shutdownRequested);
                 shutdownRequested = true;
             }
 
@@ -162,8 +162,8 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckState(startRequested);
-                Preconditions.CheckState(!shutdownRequested);
+                GrpcPreconditions.CheckState(startRequested);
+                GrpcPreconditions.CheckState(!shutdownRequested);
                 shutdownRequested = true;
             }
 
@@ -181,7 +181,7 @@ namespace Grpc.Core
 
             bool success = false;
             handle.DangerousAddRef(ref success);
-            Preconditions.CheckState(success);
+            GrpcPreconditions.CheckState(success);
         }
 
         internal void RemoveCallReference(object call)
@@ -197,7 +197,7 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!startRequested);
+                GrpcPreconditions.CheckState(!startRequested);
                 foreach (var entry in serviceDefinition.CallHandlers)
                 {
                     callHandlers.Add(entry.Key, entry.Value);
@@ -213,8 +213,8 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(serverPort.Credentials, "serverPort");
-                Preconditions.CheckState(!startRequested);
+                GrpcPreconditions.CheckNotNull(serverPort.Credentials, "serverPort");
+                GrpcPreconditions.CheckState(!startRequested);
                 var address = string.Format("{0}:{1}", serverPort.Host, serverPort.Port);
                 int boundPort;
                 using (var nativeCredentials = serverPort.Credentials.ToNativeCredentials())
diff --git a/src/csharp/Grpc.Core/ServerCredentials.cs b/src/csharp/Grpc.Core/ServerCredentials.cs
index 3c6703d30e..456d331c9c 100644
--- a/src/csharp/Grpc.Core/ServerCredentials.cs
+++ b/src/csharp/Grpc.Core/ServerCredentials.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -90,11 +90,11 @@ namespace Grpc.Core
         public SslServerCredentials(IEnumerable<KeyCertificatePair> keyCertificatePairs, string rootCertificates, bool forceClientAuth)
         {
             this.keyCertificatePairs = new List<KeyCertificatePair>(keyCertificatePairs).AsReadOnly();
-            Preconditions.CheckArgument(this.keyCertificatePairs.Count > 0,
+            GrpcPreconditions.CheckArgument(this.keyCertificatePairs.Count > 0,
                 "At least one KeyCertificatePair needs to be provided.");
             if (forceClientAuth)
             {
-                Preconditions.CheckNotNull(rootCertificates,
+                GrpcPreconditions.CheckNotNull(rootCertificates,
                     "Cannot force client authentication unless you provide rootCertificates.");
             }
             this.rootCertificates = rootCertificates;
diff --git a/src/csharp/Grpc.Core/ServerPort.cs b/src/csharp/Grpc.Core/ServerPort.cs
index 598404d045..10ddcb782f 100644
--- a/src/csharp/Grpc.Core/ServerPort.cs
+++ b/src/csharp/Grpc.Core/ServerPort.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -62,9 +62,9 @@ namespace Grpc.Core
         /// <param name="credentials">credentials to use to secure this port.</param>
         public ServerPort(string host, int port, ServerCredentials credentials)
         {
-            this.host = Preconditions.CheckNotNull(host, "host");
+            this.host = GrpcPreconditions.CheckNotNull(host, "host");
             this.port = port;
-            this.credentials = Preconditions.CheckNotNull(credentials, "credentials");
+            this.credentials = GrpcPreconditions.CheckNotNull(credentials, "credentials");
         }
 
         /// <summary>
diff --git a/src/csharp/Grpc.Core/Utils/Preconditions.cs b/src/csharp/Grpc.Core/Utils/GrpcPreconditions.cs
index a8ab603391..76bf04ce8b 100644
--- a/src/csharp/Grpc.Core/Utils/Preconditions.cs
+++ b/src/csharp/Grpc.Core/Utils/GrpcPreconditions.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -38,7 +38,7 @@ namespace Grpc.Core.Utils
     /// <summary>
     /// Utility methods to simplify checking preconditions in the code.
     /// </summary>
-    public static class Preconditions
+    public static class GrpcPreconditions
     {
         /// <summary>
         /// Throws <see cref="ArgumentException"/> if condition is false.
diff --git a/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs b/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs
index 26c6445c35..e2ad1a834b 100644
--- a/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs
+++ b/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs
@@ -1,5 +1,5 @@
 #region Copyright notice and license
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -127,8 +127,8 @@ namespace Grpc.HealthCheck
         {
             public Key(string host, string service)
             {
-                this.Host = Preconditions.CheckNotNull(host);
-                this.Service = Preconditions.CheckNotNull(service);
+                this.Host = GrpcPreconditions.CheckNotNull(host);
+                this.Service = GrpcPreconditions.CheckNotNull(service);
             }
 
             readonly string Host;
diff --git a/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs b/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs
index e9e659cb1f..c4016012cb 100644
--- a/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs
+++ b/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -58,7 +58,7 @@ namespace Grpc.IntegrationTesting
         public static IClientRunner CreateStarted(ClientConfig config)
         {
             string target = config.ServerTargets.Single();
-            Grpc.Core.Utils.Preconditions.CheckArgument(config.LoadParams.LoadCase == LoadParams.LoadOneofCase.ClosedLoop);
+            GrpcPreconditions.CheckArgument(config.LoadParams.LoadCase == LoadParams.LoadOneofCase.ClosedLoop);
 
             var credentials = config.SecurityParams != null ? TestCredentials.CreateSslCredentials() : ChannelCredentials.Insecure;
             var channel = new Channel(target, credentials);
@@ -95,7 +95,7 @@ namespace Grpc.IntegrationTesting
         
         public SyncUnaryClientRunner(Channel channel, int payloadSize, HistogramParams histogramParams)
         {
-            this.channel = Grpc.Core.Utils.Preconditions.CheckNotNull(channel);
+            this.channel = GrpcPreconditions.CheckNotNull(channel);
             this.payloadSize = payloadSize;
             this.histogram = new Histogram(histogramParams.Resolution, histogramParams.MaxPossible);
 
diff --git a/src/csharp/Grpc.IntegrationTesting/Histogram.cs b/src/csharp/Grpc.IntegrationTesting/Histogram.cs
index 7e7cb2c4de..08a674d817 100644
--- a/src/csharp/Grpc.IntegrationTesting/Histogram.cs
+++ b/src/csharp/Grpc.IntegrationTesting/Histogram.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -66,8 +66,8 @@ namespace Grpc.IntegrationTesting
 
         public Histogram(double resolution, double maxPossible)
         {
-            Grpc.Core.Utils.Preconditions.CheckArgument(resolution > 0);
-            Grpc.Core.Utils.Preconditions.CheckArgument(maxPossible > 0);
+            GrpcPreconditions.CheckArgument(resolution > 0);
+            GrpcPreconditions.CheckArgument(maxPossible > 0);
             this.maxPossible = maxPossible;
             this.multiplier = 1.0 + resolution;
             this.oneOnLogMultiplier = 1.0 / Math.Log(1.0 + resolution);
diff --git a/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs b/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs
index e8be7758ce..9b09b9bdd3 100644
--- a/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs
+++ b/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -57,7 +57,7 @@ namespace Grpc.IntegrationTesting
         /// </summary>
         public static IServerRunner CreateStarted(ServerConfig config)
         {
-            Grpc.Core.Utils.Preconditions.CheckArgument(config.ServerType == ServerType.ASYNC_SERVER);
+            GrpcPreconditions.CheckArgument(config.ServerType == ServerType.ASYNC_SERVER);
             var credentials = config.SecurityParams != null ? TestCredentials.CreateSslServerCredentials() : ServerCredentials.Insecure;
 
             // TODO: qps_driver needs to setup payload properly...
@@ -83,7 +83,7 @@ namespace Grpc.IntegrationTesting
 
         public ServerRunnerImpl(Server server)
         {
-            this.server = Grpc.Core.Utils.Preconditions.CheckNotNull(server);
+            this.server = GrpcPreconditions.CheckNotNull(server);
         }
 
         public int BoundPort
diff --git a/src/csharp/Grpc.IntegrationTesting/WorkerServiceImpl.cs b/src/csharp/Grpc.IntegrationTesting/WorkerServiceImpl.cs
index bb2918bf46..59ecebf5a2 100644
--- a/src/csharp/Grpc.IntegrationTesting/WorkerServiceImpl.cs
+++ b/src/csharp/Grpc.IntegrationTesting/WorkerServiceImpl.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -49,7 +49,7 @@ namespace Grpc.Testing
     {
         public async Task RunServer(IAsyncStreamReader<ServerArgs> requestStream, IServerStreamWriter<ServerStatus> responseStream, ServerCallContext context)
         {
-            Grpc.Core.Utils.Preconditions.CheckState(await requestStream.MoveNext());
+            GrpcPreconditions.CheckState(await requestStream.MoveNext());
             var serverConfig = requestStream.Current.Setup;
             var runner = ServerRunners.CreateStarted(serverConfig);
 
@@ -73,7 +73,7 @@ namespace Grpc.Testing
 
         public async Task RunClient(IAsyncStreamReader<ClientArgs> requestStream, IServerStreamWriter<ClientStatus> responseStream, ServerCallContext context)
         {
-            Grpc.Core.Utils.Preconditions.CheckState(await requestStream.MoveNext());
+            GrpcPreconditions.CheckState(await requestStream.MoveNext());
             var clientConfig = requestStream.Current.Setup;
             var runner = ClientRunners.CreateStarted(clientConfig);
 
diff --git a/src/node/ext/call_credentials.cc b/src/node/ext/call_credentials.cc
index 91acb86254..98696db232 100644
--- a/src/node/ext/call_credentials.cc
+++ b/src/node/ext/call_credentials.cc
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2015, Google Inc.
+ * Copyright 2015-2016, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -187,7 +187,8 @@ NAN_METHOD(PluginCallback) {
   shared_ptr<Resources> resources(new Resources);
   grpc_status_code code = static_cast<grpc_status_code>(
       Nan::To<uint32_t>(info[0]).FromJust());
-  char *details = *Utf8String(info[1]);
+  Utf8String details_utf8_str(info[1]);
+  char *details = *details_utf8_str;
   grpc_metadata_array array;
   if (!CreateMetadataArray(Nan::To<Object>(info[2]).ToLocalChecked(),
                            &array, resources)){
diff --git a/src/node/ext/node_grpc.cc b/src/node/ext/node_grpc.cc
index 654c5aed09..0c71b2d610 100644
--- a/src/node/ext/node_grpc.cc
+++ b/src/node/ext/node_grpc.cc
@@ -237,7 +237,8 @@ NAN_METHOD(MetadataKeyIsLegal) {
         "headerKeyIsLegal's argument must be a string");
   }
   Local<String> key = Nan::To<String>(info[0]).ToLocalChecked();
-  char *key_str = *Nan::Utf8String(key);
+  Nan::Utf8String key_utf8_str(key);
+  char *key_str = *key_utf8_str;
   info.GetReturnValue().Set(static_cast<bool>(
       grpc_header_key_is_legal(key_str, static_cast<size_t>(key->Length()))));
 }
@@ -248,7 +249,8 @@ NAN_METHOD(MetadataNonbinValueIsLegal) {
         "metadataNonbinValueIsLegal's argument must be a string");
   }
   Local<String> value = Nan::To<String>(info[0]).ToLocalChecked();
-  char *value_str = *Nan::Utf8String(value);
+  Nan::Utf8String value_utf8_str(value);
+  char *value_str = *value_utf8_str;
   info.GetReturnValue().Set(static_cast<bool>(
       grpc_header_nonbin_value_is_legal(
           value_str, static_cast<size_t>(value->Length()))));
@@ -260,7 +262,8 @@ NAN_METHOD(MetadataKeyIsBinary) {
         "metadataKeyIsLegal's argument must be a string");
   }
   Local<String> key = Nan::To<String>(info[0]).ToLocalChecked();
-  char *key_str = *Nan::Utf8String(key);
+  Nan::Utf8String key_utf8_str(key);
+  char *key_str = *key_utf8_str;
   info.GetReturnValue().Set(static_cast<bool>(
       grpc_is_binary_header(key_str, static_cast<size_t>(key->Length()))));
 }
diff --git a/src/node/index.js b/src/node/index.js
index 7eacdc67b1..1c197729d7 100644
--- a/src/node/index.js
+++ b/src/node/index.js
@@ -56,17 +56,18 @@ var grpc = require('./src/grpc_extension');
 /**
  * Load a gRPC object from an existing ProtoBuf.Reflect object.
  * @param {ProtoBuf.Reflect.Namespace} value The ProtoBuf object to load.
+ * @param {Object=} options Options to apply to the loaded object
  * @return {Object<string, *>} The resulting gRPC object
  */
-exports.loadObject = function loadObject(value) {
+exports.loadObject = function loadObject(value, options) {
   var result = {};
   if (value.className === 'Namespace') {
     _.each(value.children, function(child) {
-      result[child.name] = loadObject(child);
+      result[child.name] = loadObject(child, options);
     });
     return result;
   } else if (value.className === 'Service') {
-    return client.makeProtobufClientConstructor(value);
+    return client.makeProtobufClientConstructor(value, options);
   } else if (value.className === 'Message' || value.className === 'Enum') {
     return value.build();
   } else {
@@ -77,28 +78,45 @@ exports.loadObject = function loadObject(value) {
 var loadObject = exports.loadObject;
 
 /**
- * Load a gRPC object from a .proto file.
- * @param {string} filename The file to load
+ * Load a gRPC object from a .proto file. The options object can provide the
+ * following options:
+ * - convertFieldsToCamelCase: Loads this file with that option on protobuf.js
+ *   set as specified. See
+ *   https://github.com/dcodeIO/protobuf.js/wiki/Advanced-options for details
+ * - binaryAsBase64: deserialize bytes values as base64 strings instead of
+ *   Buffers. Defaults to false
+ * - longsAsStrings: deserialize long values as strings instead of objects.
+ *   Defaults to true
+ * @param {string|{root: string, file: string}} filename The file to load
  * @param {string=} format The file format to expect. Must be either 'proto' or
  *     'json'. Defaults to 'proto'
+ * @param {Object=} options Options to apply to the loaded file
  * @return {Object<string, *>} The resulting gRPC object
  */
-exports.load = function load(filename, format) {
+exports.load = function load(filename, format, options) {
   if (!format) {
     format = 'proto';
   }
+  var convertFieldsToCamelCaseOriginal = ProtoBuf.convertFieldsToCamelCase;
+  if(options && options.hasOwnProperty('convertFieldsToCamelCase')) {
+    ProtoBuf.convertFieldsToCamelCase = options.convertFieldsToCamelCase;
+  }
   var builder;
-  switch(format) {
-    case 'proto':
-    builder = ProtoBuf.loadProtoFile(filename);
-    break;
-    case 'json':
-    builder = ProtoBuf.loadJsonFile(filename);
-    break;
-    default:
-    throw new Error('Unrecognized format "' + format + '"');
+  try {
+    switch(format) {
+      case 'proto':
+      builder = ProtoBuf.loadProtoFile(filename);
+      break;
+      case 'json':
+      builder = ProtoBuf.loadJsonFile(filename);
+      break;
+      default:
+      throw new Error('Unrecognized format "' + format + '"');
+    }
+  } finally {
+    ProtoBuf.convertFieldsToCamelCase = convertFieldsToCamelCaseOriginal;
   }
-  return loadObject(builder.ns);
+  return loadObject(builder.ns, options);
 };
 
 /**
diff --git a/src/node/src/client.js b/src/node/src/client.js
index b5247a69ee..c65dd73650 100644
--- a/src/node/src/client.js
+++ b/src/node/src/client.js
@@ -648,8 +648,8 @@ exports.makeClientConstructor = function(methods, serviceName) {
     var deserialize = attrs.responseDeserialize;
     Client.prototype[name] = requester_makers[method_type](
         attrs.path, serialize, deserialize);
-    Client.prototype[name].serialize = serialize;
-    Client.prototype[name].deserialize = deserialize;
+    // Associate all provided attributes with the method
+    _.assign(Client.prototype[name], attrs);
   });
 
   return Client;
@@ -698,13 +698,16 @@ exports.waitForClientReady = function(client, deadline, callback) {
  * Creates a constructor for clients for the given service
  * @param {ProtoBuf.Reflect.Service} service The service to generate a client
  *     for
+ * @param {Object=} options Options to apply to the client
  * @return {function(string, Object)} New client constructor
  */
-exports.makeProtobufClientConstructor =  function(service) {
-  var method_attrs = common.getProtobufServiceAttrs(service, service.name);
+exports.makeProtobufClientConstructor =  function(service, options) {
+  var method_attrs = common.getProtobufServiceAttrs(service, service.name,
+                                                    options);
   var Client = exports.makeClientConstructor(
       method_attrs, common.fullyQualifiedName(service));
   Client.service = service;
+  Client.service.grpc_options = options;
   return Client;
 };
 
diff --git a/src/node/src/common.js b/src/node/src/common.js
index 2e6c01c4d7..7705a275fc 100644
--- a/src/node/src/common.js
+++ b/src/node/src/common.js
@@ -44,9 +44,20 @@ var _ = require('lodash');
 /**
  * Get a function that deserializes a specific type of protobuf.
  * @param {function()} cls The constructor of the message type to deserialize
+ * @param {bool=} binaryAsBase64 Deserialize bytes fields as base64 strings
+ *     instead of Buffers. Defaults to false
+ * @param {bool=} longsAsStrings Deserialize long values as strings instead of
+ *     objects. Defaults to true
  * @return {function(Buffer):cls} The deserialization function
  */
-exports.deserializeCls = function deserializeCls(cls) {
+exports.deserializeCls = function deserializeCls(cls, binaryAsBase64,
+                                                 longsAsStrings) {
+  if (binaryAsBase64 === undefined || binaryAsBase64 === null) {
+    binaryAsBase64 = false;
+  }
+  if (longsAsStrings === undefined || longsAsStrings === null) {
+    longsAsStrings = true;
+  }
   /**
    * Deserialize a buffer to a message object
    * @param {Buffer} arg_buf The buffer to deserialize
@@ -55,7 +66,7 @@ exports.deserializeCls = function deserializeCls(cls) {
   return function deserialize(arg_buf) {
     // Convert to a native object with binary fields as Buffers (first argument)
     // and longs as strings (second argument)
-    return cls.decode(arg_buf).toRaw(false, true);
+    return cls.decode(arg_buf).toRaw(binaryAsBase64, longsAsStrings);
   };
 };
 
@@ -119,19 +130,30 @@ exports.wrapIgnoreNull = function wrapIgnoreNull(func) {
 /**
  * Return a map from method names to method attributes for the service.
  * @param {ProtoBuf.Reflect.Service} service The service to get attributes for
+ * @param {Object=} options Options to apply to these attributes
  * @return {Object} The attributes map
  */
-exports.getProtobufServiceAttrs = function getProtobufServiceAttrs(service) {
+exports.getProtobufServiceAttrs = function getProtobufServiceAttrs(service,
+                                                                   options) {
   var prefix = '/' + fullyQualifiedName(service) + '/';
+  var binaryAsBase64, longsAsStrings;
+  if (options) {
+    binaryAsBase64 = options.binaryAsBase64;
+    longsAsStrings = options.longsAsStrings;
+  }
   return _.object(_.map(service.children, function(method) {
     return [_.camelCase(method.name), {
       path: prefix + method.name,
       requestStream: method.requestStream,
       responseStream: method.responseStream,
+      requestType: method.resolvedRequestType,
+      responseType: method.resolvedResponseType,
       requestSerialize: serializeCls(method.resolvedRequestType.build()),
-      requestDeserialize: deserializeCls(method.resolvedRequestType.build()),
+      requestDeserialize: deserializeCls(method.resolvedRequestType.build(),
+                                     binaryAsBase64, longsAsStrings),
       responseSerialize: serializeCls(method.resolvedResponseType.build()),
-      responseDeserialize: deserializeCls(method.resolvedResponseType.build())
+      responseDeserialize: deserializeCls(method.resolvedResponseType.build(),
+                                     binaryAsBase64, longsAsStrings)
     }];
   }));
 };
diff --git a/src/node/src/credentials.js b/src/node/src/credentials.js
index 710ab6d879..1d73723cc0 100644
--- a/src/node/src/credentials.js
+++ b/src/node/src/credentials.js
@@ -98,6 +98,8 @@ exports.createFromMetadataGenerator = function(metadata_generator) {
         message = error.message;
         if (error.hasOwnProperty('code')) {
           code = error.code;
+        } else {
+          code = grpc.status.UNAUTHENTICATED;
         }
         if (!metadata) {
           metadata = new Metadata();
@@ -116,13 +118,16 @@ exports.createFromMetadataGenerator = function(metadata_generator) {
 exports.createFromGoogleCredential = function(google_credential) {
   return exports.createFromMetadataGenerator(function(auth_context, callback) {
     var service_url = auth_context.service_url;
+    console.log('Service URL:', service_url);
     google_credential.getRequestMetadata(service_url, function(err, header) {
       if (err) {
+        console.log('Auth error:', err);
         callback(err);
         return;
       }
       var metadata = new Metadata();
       metadata.add('authorization', header.Authorization);
+      console.log(header.Authorization);
       callback(null, metadata);
     });
   });
diff --git a/src/node/src/metadata.js b/src/node/src/metadata.js
index 51a9f8a216..33d7ea1cf7 100644
--- a/src/node/src/metadata.js
+++ b/src/node/src/metadata.js
@@ -64,7 +64,7 @@ function normalizeKey(key) {
   if (grpc.metadataKeyIsLegal(key)) {
     return key;
   } else {
-    throw new Error('Metadata key contains illegal characters');
+    throw new Error('Metadata key"' + key + '" contains illegal characters');
   }
 }
 
@@ -79,7 +79,8 @@ function validate(key, value) {
           'keys that don\'t end with \'-bin\' must have String values');
     }
     if (!grpc.metadataNonbinValueIsLegal(value)) {
-      throw new Error('Metadata string value contains illegal characters');
+      throw new Error('Metadata string value "' + value +
+                      '" contains illegal characters');
     }
   }
 }
diff --git a/src/node/src/server.js b/src/node/src/server.js
index e5aadcd565..0cf7ba3424 100644
--- a/src/node/src/server.js
+++ b/src/node/src/server.js
@@ -737,7 +737,12 @@ Server.prototype.addService = function(service, implementation) {
  *     method implementation for the provided service.
  */
 Server.prototype.addProtoService = function(service, implementation) {
-  this.addService(common.getProtobufServiceAttrs(service), implementation);
+  var options;
+  if (service.grpc_options) {
+    options = service.grpc_options;
+  }
+  this.addService(common.getProtobufServiceAttrs(service, options),
+                  implementation);
 };
 
 /**
diff --git a/src/node/test/common_test.js b/src/node/test/common_test.js
index 08ba429ed7..66a4205f82 100644
--- a/src/node/test/common_test.js
+++ b/src/node/test/common_test.js
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2015, Google Inc.
+ * Copyright 2015-2016, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -42,7 +42,7 @@ var ProtoBuf = require('protobufjs');
 var messages_proto = ProtoBuf.loadProtoFile(
     __dirname + '/test_messages.proto').build();
 
-describe('Proto message serialize and deserialize', function() {
+describe('Proto message long int serialize and deserialize', function() {
   var longSerialize = common.serializeCls(messages_proto.LongValues);
   var longDeserialize = common.deserializeCls(messages_proto.LongValues);
   var pos_value = '314159265358979';
@@ -87,4 +87,52 @@ describe('Proto message serialize and deserialize', function() {
     assert.strictEqual(longDeserialize(serialized).sfixed_64.toString(),
                        neg_value);
   });
+  it('should deserialize as a number with the right option set', function() {
+    var longNumDeserialize = common.deserializeCls(messages_proto.LongValues,
+                                                   false, false);
+    var serialized = longSerialize({int_64: pos_value});
+    assert.strictEqual(typeof longDeserialize(serialized).int_64, 'string');
+    /* With the longsAsStrings option disabled, long values are represented as
+     * objects with 3 keys: low, high, and unsigned */
+    assert.strictEqual(typeof longNumDeserialize(serialized).int_64, 'object');
+  });
+});
+describe('Proto message bytes serialize and deserialize', function() {
+  var sequenceSerialize = common.serializeCls(messages_proto.SequenceValues);
+  var sequenceDeserialize = common.deserializeCls(
+      messages_proto.SequenceValues);
+  var sequenceBase64Deserialize = common.deserializeCls(
+      messages_proto.SequenceValues, true);
+  var buffer_val = new Buffer([0x69, 0xb7]);
+  var base64_val = 'abc=';
+  it('should preserve a buffer', function() {
+    var serialized = sequenceSerialize({bytes_field: buffer_val});
+    var deserialized = sequenceDeserialize(serialized);
+    assert.strictEqual(deserialized.bytes_field.compare(buffer_val), 0);
+  });
+  it('should accept base64 encoded strings', function() {
+    var serialized = sequenceSerialize({bytes_field: base64_val});
+    var deserialized = sequenceDeserialize(serialized);
+    assert.strictEqual(deserialized.bytes_field.compare(buffer_val), 0);
+  });
+  it('should output base64 encoded strings with an option set', function() {
+    var serialized = sequenceSerialize({bytes_field: base64_val});
+    var deserialized = sequenceBase64Deserialize(serialized);
+    assert.strictEqual(deserialized.bytes_field, base64_val);
+  });
+  /* The next two tests are specific tests to verify that issue
+   * https://github.com/grpc/grpc/issues/5174 has been fixed. They are skipped
+   * because they will not pass until a protobuf.js release has been published
+   * with a fix for https://github.com/dcodeIO/protobuf.js/issues/390 */
+  it.skip('should serialize a repeated field as packed by default', function() {
+    var expected_serialize = new Buffer([0x12, 0x01, 0x01, 0x0a]);
+    var serialized = sequenceSerialize({repeated_field: [10]});
+    assert.strictEqual(expected_serialize.compare(serialized), 0);
+  });
+  it.skip('should deserialize packed or unpacked repeated', function() {
+    var serialized = new Buffer([0x12, 0x01, 0x01, 0x0a]);
+    assert.doesNotThrow(function() {
+      sequenceDeserialize(serialized);
+    });
+  });
 });
diff --git a/src/node/test/test_messages.proto b/src/node/test/test_messages.proto
index c77a937d3f..9b8cb875ee 100644
--- a/src/node/test/test_messages.proto
+++ b/src/node/test/test_messages.proto
@@ -36,3 +36,8 @@ message LongValues {
   fixed64 fixed_64 = 4;
   sfixed64 sfixed_64 = 5;
 }
+
+message SequenceValues {
+  bytes bytes_field = 1;
+  repeated int32 repeated_field = 2;
+}
diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py
index 5d7e31ba01..c020fda284 100644
--- a/src/python/grpcio/grpc_core_dependencies.py
+++ b/src/python/grpcio/grpc_core_dependencies.py
@@ -73,27 +73,6 @@ CORE_SOURCE_FILES = [
   'src/core/support/time_win32.c',
   'src/core/support/tls_pthread.c',
   'src/core/support/wrap_memcpy.c',
-  'src/core/httpcli/httpcli_security_connector.c',
-  'src/core/security/base64.c',
-  'src/core/security/client_auth_filter.c',
-  'src/core/security/credentials.c',
-  'src/core/security/credentials_metadata.c',
-  'src/core/security/credentials_posix.c',
-  'src/core/security/credentials_win32.c',
-  'src/core/security/google_default_credentials.c',
-  'src/core/security/handshake.c',
-  'src/core/security/json_token.c',
-  'src/core/security/jwt_verifier.c',
-  'src/core/security/secure_endpoint.c',
-  'src/core/security/security_connector.c',
-  'src/core/security/security_context.c',
-  'src/core/security/server_auth_filter.c',
-  'src/core/security/server_secure_chttp2.c',
-  'src/core/surface/init_secure.c',
-  'src/core/surface/secure_channel_create.c',
-  'src/core/tsi/fake_transport_security.c',
-  'src/core/tsi/ssl_transport_security.c',
-  'src/core/tsi/transport_security.c',
   'src/core/census/grpc_context.c',
   'src/core/census/grpc_filter.c',
   'src/core/channel/channel_args.c',
@@ -224,9 +203,30 @@ CORE_SOURCE_FILES = [
   'src/core/transport/static_metadata.c',
   'src/core/transport/transport.c',
   'src/core/transport/transport_op_string.c',
+  'src/core/httpcli/httpcli_security_connector.c',
+  'src/core/security/base64.c',
+  'src/core/security/client_auth_filter.c',
+  'src/core/security/credentials.c',
+  'src/core/security/credentials_metadata.c',
+  'src/core/security/credentials_posix.c',
+  'src/core/security/credentials_win32.c',
+  'src/core/security/google_default_credentials.c',
+  'src/core/security/handshake.c',
+  'src/core/security/json_token.c',
+  'src/core/security/jwt_verifier.c',
+  'src/core/security/secure_endpoint.c',
+  'src/core/security/security_connector.c',
+  'src/core/security/security_context.c',
+  'src/core/security/server_auth_filter.c',
+  'src/core/security/server_secure_chttp2.c',
+  'src/core/surface/init_secure.c',
+  'src/core/surface/secure_channel_create.c',
+  'src/core/tsi/fake_transport_security.c',
+  'src/core/tsi/ssl_transport_security.c',
+  'src/core/tsi/transport_security.c',
   'src/core/census/context.c',
   'src/core/census/initialize.c',
-  'src/core/census/log.c',
+  'src/core/census/mlog.c',
   'src/core/census/operation.c',
   'src/core/census/placeholders.c',
   'src/core/census/tracing.c',