Merge branch 'master' of github.com:grpc/grpc into compression-accept-encoding

136 files changed, 2488 insertions, 969 deletions

diff --git a/INSTALL b/INSTALL
index 5edb5e6db2..8a0a98ad2e 100644
--- a/INSTALL
+++ b/INSTALL
@@ -117,7 +117,7 @@ most Mac installations. Do the "git submodule" command listed above.
 Then execute the following for all the needed build dependencies
 
   $ sudo /opt/local/bin/port install autoconf automake libtool gflags cmake
-  $ mkdir ~/gtest
+  $ mkdir ~/gtest-svn
   $ svn checkout http://googletest.googlecode.com/svn/trunk/ gtest-svn
   $ mkdir mybuild
   $ cd mybuild
diff --git a/Makefile b/Makefile
index 86bdbd36ca..ffcd2a2450 100644
--- a/Makefile
+++ b/Makefile
@@ -145,7 +145,7 @@ CC_tsan = clang
 CXX_tsan = clang++
 LD_tsan = clang
 LDXX_tsan = clang++
-CPPFLAGS_tsan = -O0 -fsanitize=thread -fno-omit-frame-pointer
+CPPFLAGS_tsan = -O0 -fsanitize=thread -fno-omit-frame-pointer -Wno-error=unused-command-line-argument
 LDFLAGS_tsan = -fsanitize=thread
 DEFINES_tsan = NDEBUG GRPC_TEST_SLOWDOWN_BUILD_FACTOR=10
 
@@ -155,7 +155,7 @@ CC_asan = clang
 CXX_asan = clang++
 LD_asan = clang
 LDXX_asan = clang++
-CPPFLAGS_asan = -O0 -fsanitize=address -fno-omit-frame-pointer
+CPPFLAGS_asan = -O0 -fsanitize=address -fno-omit-frame-pointer -Wno-error=unused-command-line-argument
 LDFLAGS_asan = -fsanitize=address
 DEFINES_asan = GRPC_TEST_SLOWDOWN_BUILD_FACTOR=3
 
@@ -165,7 +165,7 @@ CC_msan = clang
 CXX_msan = clang++-libc++
 LD_msan = clang
 LDXX_msan = clang++-libc++
-CPPFLAGS_msan = -O0 -fsanitize=memory -fsanitize-memory-track-origins -fno-omit-frame-pointer -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1
+CPPFLAGS_msan = -O0 -fsanitize=memory -fsanitize-memory-track-origins -fno-omit-frame-pointer -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1 -Wno-error=unused-command-line-argument
 OPENSSL_CFLAGS_msan = -DPURIFY
 LDFLAGS_msan = -fsanitize=memory -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1
 DEFINES_msan = NDEBUG GRPC_TEST_SLOWDOWN_BUILD_FACTOR=4
@@ -176,7 +176,7 @@ CC_ubsan = clang
 CXX_ubsan = clang++
 LD_ubsan = clang
 LDXX_ubsan = clang++
-CPPFLAGS_ubsan = -O1 -fsanitize=undefined -fno-omit-frame-pointer
+CPPFLAGS_ubsan = -O1 -fsanitize=undefined -fno-omit-frame-pointer -Wno-error=unused-command-line-argument
 OPENSSL_CFLAGS_ubsan = -DPURIFY
 LDFLAGS_ubsan = -fsanitize=undefined
 DEFINES_ubsan = NDEBUG GRPC_TEST_SLOWDOWN_BUILD_FACTOR=3
@@ -241,10 +241,6 @@ HOST_CXX = $(CXX)
 HOST_LD = $(LD)
 HOST_LDXX = $(LDXX)
 
-CPPFLAGS += $(CPPFLAGS_$(CONFIG))
-DEFINES += $(DEFINES_$(CONFIG)) INSTALL_PREFIX=\"$(prefix)\"
-LDFLAGS += $(LDFLAGS_$(CONFIG))
-
 ifdef EXTRA_DEFINES
 DEFINES += $(EXTRA_DEFINES)
 endif
@@ -258,6 +254,10 @@ endif
 CPPFLAGS += -g -Wall -Wextra -Werror -Wno-long-long -Wno-unused-parameter
 LDFLAGS += -g
 
+CPPFLAGS += $(CPPFLAGS_$(CONFIG))
+DEFINES += $(DEFINES_$(CONFIG)) INSTALL_PREFIX=\"$(prefix)\"
+LDFLAGS += $(LDFLAGS_$(CONFIG))
+
 ifneq ($(SYSTEM),MINGW32)
 PIC_CPPFLAGS = -fPIC
 CPPFLAGS += -fPIC
@@ -1444,7 +1444,7 @@ run_dep_checks:
 
 $(LIBDIR)/$(CONFIG)/zlib/libz.a:
 	$(E) "[MAKE]    Building zlib"
-	$(Q)(cd third_party/zlib ; CC="$(CC)" CFLAGS="$(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG))" ./configure --static)
+	$(Q)(cd third_party/zlib ; CC="$(CC)" CFLAGS="$(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG)) $(ZLIB_CFLAGS_EXTRA)" ./configure --static)
 	$(Q)$(MAKE) -C third_party/zlib clean
 	$(Q)$(MAKE) -C third_party/zlib
 	$(Q)mkdir -p $(LIBDIR)/$(CONFIG)/zlib
@@ -1453,7 +1453,7 @@ $(LIBDIR)/$(CONFIG)/zlib/libz.a:
 $(LIBDIR)/$(CONFIG)/openssl/libssl.a:
 	$(E) "[MAKE]    Building openssl for $(SYSTEM)"
 ifeq ($(SYSTEM),Darwin)
-	$(Q)(cd third_party/openssl ; CC="$(CC) $(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_$(CONFIG))" ./Configure darwin64-x86_64-cc)
+	$(Q)(cd third_party/openssl ; CC="$(CC) $(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_EXTRA)" ./Configure darwin64-x86_64-cc)
 else
 ifeq ($(SYSTEM),MINGW32)
 	@echo "We currently don't have a good way to compile OpenSSL in-place under msys."
@@ -1474,7 +1474,7 @@ ifeq ($(SYSTEM),MINGW32)
 	@echo "  CPPFLAGS=-I/c/OpenSSL-Win64/include LDFLAGS=-L/c/OpenSSL-Win64 make"
 	@false
 else
-	$(Q)(cd third_party/openssl ; CC="$(CC) $(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_$(CONFIG))" ./config no-asm $(OPENSSL_CONFIG_$(CONFIG)))
+	$(Q)(cd third_party/openssl ; CC="$(CC) $(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_EXTRA)" ./config no-asm $(OPENSSL_CONFIG_$(CONFIG)))
 endif
 endif
 	$(Q)$(MAKE) -C third_party/openssl clean
@@ -1488,7 +1488,7 @@ third_party/protobuf/configure:
 
 $(LIBDIR)/$(CONFIG)/protobuf/libprotobuf.a: third_party/protobuf/configure
 	$(E) "[MAKE]    Building protobuf"
-	$(Q)(cd third_party/protobuf ; CC="$(CC)" CXX="$(CXX)" LDFLAGS="$(LDFLAGS_$(CONFIG)) -g" CPPFLAGS="$(PIC_CPPFLAGS) $(CPPFLAGS_$(CONFIG)) -g" ./configure --disable-shared --enable-static)
+	$(Q)(cd third_party/protobuf ; CC="$(CC)" CXX="$(CXX)" LDFLAGS="$(LDFLAGS_$(CONFIG)) -g $(PROTOBUF_LDFLAGS_EXTRA)" CPPFLAGS="$(PIC_CPPFLAGS) $(CPPFLAGS_$(CONFIG)) -g $(PROTOBUF_CPPFLAGS_EXTRA)" ./configure --disable-shared --enable-static)
 	$(Q)$(MAKE) -C third_party/protobuf clean
 	$(Q)$(MAKE) -C third_party/protobuf
 	$(Q)mkdir -p $(LIBDIR)/$(CONFIG)/protobuf
diff --git a/gRPC.podspec b/gRPC.podspec
index 5c9089eb9d..28d9ac4c53 100644
--- a/gRPC.podspec
+++ b/gRPC.podspec
@@ -36,14 +36,14 @@
 
 Pod::Spec.new do |s|
   s.name     = 'gRPC'
-  s.version  = '0.6.0'
+  s.version  = '0.7.0'
   s.summary  = 'gRPC client library for iOS/OSX'
   s.homepage = 'http://www.grpc.io'
   s.license  = 'New BSD'
   s.authors  = { 'The gRPC contributors' => 'grpc-packages@google.com' }
 
   # s.source = { :git => 'https://github.com/grpc/grpc.git',
-  #              :tag => 'release-0_9_1-objectivec-0.5.1' }
+  #              :tag => 'release-0_10_0-objectivec-0.6.0' }
 
   s.ios.deployment_target = '6.0'
   s.osx.deployment_target = '10.8'
@@ -518,6 +518,8 @@ Pod::Spec.new do |s|
     ss.requires_arc = false
     ss.libraries = 'z'
     ss.dependency 'OpenSSL', '~> 1.0.200'
+
+    # ss.compiler_flags = '-GCC_WARN_INHIBIT_ALL_WARNINGS', '-w'
   end
 
   # This is a workaround for Cocoapods Issue #1437.
diff --git a/include/grpc++/channel_arguments.h b/include/grpc++/channel_arguments.h
index 7b17830a86..4d926377ec 100644
--- a/include/grpc++/channel_arguments.h
+++ b/include/grpc++/channel_arguments.h
@@ -54,14 +54,21 @@ class ChannelArguments {
   ChannelArguments() {}
   ~ChannelArguments() {}
 
+  ChannelArguments(const ChannelArguments& other);
+  ChannelArguments& operator=(ChannelArguments other) {
+    Swap(other);
+    return *this;
+  }
+
+  void Swap(ChannelArguments& other);
+
   // grpc specific channel argument setters
   // Set target name override for SSL host name checking.
   void SetSslTargetNameOverride(const grpc::string& name);
   // TODO(yangg) add flow control options
 
   // Set the compression algorithm for the channel.
-  void _Experimental_SetCompressionAlgorithm(
-      grpc_compression_algorithm algorithm);
+  void SetCompressionAlgorithm(grpc_compression_algorithm algorithm);
 
   // Generic channel argument setters. Only for advanced use cases.
   void SetInt(const grpc::string& key, int value);
@@ -74,10 +81,6 @@ class ChannelArguments {
   friend class SecureCredentials;
   friend class testing::ChannelArgumentsTest;
 
-  // TODO(yangg) implement copy and assign
-  ChannelArguments(const ChannelArguments&);
-  ChannelArguments& operator=(const ChannelArguments&);
-
   // Returns empty string when it is not set.
   grpc::string GetSslTargetNameOverride() const;
 
diff --git a/include/grpc++/client_context.h b/include/grpc++/client_context.h
index 6b8d7211d1..9df76699d2 100644
--- a/include/grpc++/client_context.h
+++ b/include/grpc++/client_context.h
@@ -110,12 +110,11 @@ class ClientContext {
     creds_ = creds;
   }
 
-  grpc_compression_algorithm _experimental_get_compression_algorithm() const {
+  grpc_compression_algorithm get_compression_algorithm() const {
     return compression_algorithm_;
   }
 
-  void _experimental_set_compression_algorithm(
-      grpc_compression_algorithm algorithm);
+  void set_compression_algorithm(grpc_compression_algorithm algorithm);
 
   std::shared_ptr<const AuthContext> auth_context() const;
 
diff --git a/include/grpc/grpc.h b/include/grpc/grpc.h
index 3c72c1db27..504f0cce03 100644
--- a/include/grpc/grpc.h
+++ b/include/grpc/grpc.h
@@ -45,40 +45,49 @@
 extern "C" {
 #endif
 
-/* Completion Queues enable notification of the completion of asynchronous
-   actions. */
+/*! \mainpage GRPC Core
+ *
+ * \section intro_sec The GRPC Core library is a low-level library designed
+ * to be wrapped by higher level libraries.
+ *
+ * The top-level API is provided in grpc.h. 
+ * Security related functionality lives in grpc_security.h.
+ */
+
+/** Completion Queues enable notification of the completion of asynchronous
+    actions. */
 typedef struct grpc_completion_queue grpc_completion_queue;
 
-/* The Channel interface allows creation of Call objects. */
+/** The Channel interface allows creation of Call objects. */
 typedef struct grpc_channel grpc_channel;
 
-/* A server listens to some port and responds to request calls */
+/** A server listens to some port and responds to request calls */
 typedef struct grpc_server grpc_server;
 
-/* A Call represents an RPC. When created, it is in a configuration state
-   allowing properties to be set until it is invoked. After invoke, the Call
-   can have messages written to it and read from it. */
+/** A Call represents an RPC. When created, it is in a configuration state
+    allowing properties to be set until it is invoked. After invoke, the Call
+    can have messages written to it and read from it. */
 typedef struct grpc_call grpc_call;
 
-/* Type specifier for grpc_arg */
+/** Type specifier for grpc_arg */
 typedef enum {
   GRPC_ARG_STRING,
   GRPC_ARG_INTEGER,
   GRPC_ARG_POINTER
 } grpc_arg_type;
 
-/* A single argument... each argument has a key and a value
+/** A single argument... each argument has a key and a value
 
-   A note on naming keys:
-     Keys are namespaced into groups, usually grouped by library, and are
-     keys for module XYZ are named XYZ.key1, XYZ.key2, etc. Module names must
-     be restricted to the regex [A-Za-z][_A-Za-z0-9]{,15}.
-     Key names must be restricted to the regex [A-Za-z][_A-Za-z0-9]{,47}.
+    A note on naming keys:
+      Keys are namespaced into groups, usually grouped by library, and are
+      keys for module XYZ are named XYZ.key1, XYZ.key2, etc. Module names must
+      be restricted to the regex [A-Za-z][_A-Za-z0-9]{,15}.
+      Key names must be restricted to the regex [A-Za-z][_A-Za-z0-9]{,47}.
 
-     GRPC core library keys are prefixed by grpc.
+    GRPC core library keys are prefixed by grpc.
 
-     Library authors are strongly encouraged to #define symbolic constants for
-     their keys so that it's possible to change them in the future. */
+    Library authors are strongly encouraged to \#define symbolic constants for
+    their keys so that it's possible to change them in the future. */
 typedef struct {
   grpc_arg_type type;
   char *key;
@@ -107,16 +116,22 @@ typedef struct {
 } grpc_channel_args;
 
 /* Channel argument keys: */
-/* Enable census for tracing and stats collection */
+/** Enable census for tracing and stats collection */
 #define GRPC_ARG_ENABLE_CENSUS "grpc.census"
-/* Maximum number of concurrent incoming streams to allow on a http2
-   connection */
+/** Maximum number of concurrent incoming streams to allow on a http2
+    connection */
 #define GRPC_ARG_MAX_CONCURRENT_STREAMS "grpc.max_concurrent_streams"
-/* Maximum message length that the channel can receive */
+/** Maximum message length that the channel can receive */
 #define GRPC_ARG_MAX_MESSAGE_LENGTH "grpc.max_message_length"
-/* Initial sequence number for http2 transports */
+/** Initial sequence number for http2 transports */
 #define GRPC_ARG_HTTP2_INITIAL_SEQUENCE_NUMBER \
   "grpc.http2.initial_sequence_number"
+/** Primary user agent: goes at the start of the user-agent metadata
+    sent on each request */
+#define GRPC_ARG_PRIMARY_USER_AGENT_STRING "grpc.primary_user_agent"
+/** Secondary user agent: goes at the end of the user-agent metadata
+    sent on each request */
+#define GRPC_ARG_SECONDARY_USER_AGENT_STRING "grpc.secondary_user_agent"
 
 /** Connectivity state of a channel. */
 typedef enum {
@@ -132,59 +147,59 @@ typedef enum {
   GRPC_CHANNEL_FATAL_FAILURE
 } grpc_connectivity_state;
 
-/* Result of a grpc call. If the caller satisfies the prerequisites of a
-   particular operation, the grpc_call_error returned will be GRPC_CALL_OK.
-   Receiving any other value listed here is an indication of a bug in the
-   caller. */
+/** Result of a grpc call. If the caller satisfies the prerequisites of a
+    particular operation, the grpc_call_error returned will be GRPC_CALL_OK.
+    Receiving any other value listed here is an indication of a bug in the
+    caller. */
 typedef enum grpc_call_error {
-  /* everything went ok */
+  /** everything went ok */
   GRPC_CALL_OK = 0,
-  /* something failed, we don't know what */
+  /** something failed, we don't know what */
   GRPC_CALL_ERROR,
-  /* this method is not available on the server */
+  /** this method is not available on the server */
   GRPC_CALL_ERROR_NOT_ON_SERVER,
-  /* this method is not available on the client */
+  /** this method is not available on the client */
   GRPC_CALL_ERROR_NOT_ON_CLIENT,
-  /* this method must be called before server_accept */
+  /** this method must be called before server_accept */
   GRPC_CALL_ERROR_ALREADY_ACCEPTED,
-  /* this method must be called before invoke */
+  /** this method must be called before invoke */
   GRPC_CALL_ERROR_ALREADY_INVOKED,
-  /* this method must be called after invoke */
+  /** this method must be called after invoke */
   GRPC_CALL_ERROR_NOT_INVOKED,
-  /* this call is already finished
-     (writes_done or write_status has already been called) */
+  /** this call is already finished
+      (writes_done or write_status has already been called) */
   GRPC_CALL_ERROR_ALREADY_FINISHED,
-  /* there is already an outstanding read/write operation on the call */
+  /** there is already an outstanding read/write operation on the call */
   GRPC_CALL_ERROR_TOO_MANY_OPERATIONS,
-  /* the flags value was illegal for this call */
+  /** the flags value was illegal for this call */
   GRPC_CALL_ERROR_INVALID_FLAGS,
-  /* invalid metadata was passed to this call */
+  /** invalid metadata was passed to this call */
   GRPC_CALL_ERROR_INVALID_METADATA,
-  /* completion queue for notification has not been registered with the server
-     */
+  /** completion queue for notification has not been registered with the 
+      server */
   GRPC_CALL_ERROR_NOT_SERVER_COMPLETION_QUEUE
 } grpc_call_error;
 
 /* Write Flags: */
-/* Hint that the write may be buffered and need not go out on the wire
-   immediately. GRPC is free to buffer the message until the next non-buffered
-   write, or until writes_done, but it need not buffer completely or at all. */
+/** Hint that the write may be buffered and need not go out on the wire
+    immediately. GRPC is free to buffer the message until the next non-buffered
+    write, or until writes_done, but it need not buffer completely or at all. */
 #define GRPC_WRITE_BUFFER_HINT (0x00000001u)
-/* Force compression to be disabled for a particular write
-   (start_write/add_metadata). Illegal on invoke/accept. */
+/** Force compression to be disabled for a particular write
+    (start_write/add_metadata). Illegal on invoke/accept. */
 #define GRPC_WRITE_NO_COMPRESS (0x00000002u)
-/* Mask of all valid flags. */
+/** Mask of all valid flags. */
 #define GRPC_WRITE_USED_MASK (GRPC_WRITE_BUFFER_HINT | GRPC_WRITE_NO_COMPRESS)
 
-/* A single metadata element */
+/** A single metadata element */
 typedef struct grpc_metadata {
   const char *key;
   const char *value;
   size_t value_length;
 
-  /* The following fields are reserved for grpc internal use.
-     There is no need to initialize them, and they will be set to garbage during
-     calls to grpc. */
+  /** The following fields are reserved for grpc internal use.
+      There is no need to initialize them, and they will be set to garbage during
+      calls to grpc. */
   struct {
     void *obfuscated[3];
   } internal_data;
@@ -235,42 +250,41 @@ void grpc_call_details_init(grpc_call_details *details);
 void grpc_call_details_destroy(grpc_call_details *details);
 
 typedef enum {
-  /* Send initial metadata: one and only one instance MUST be sent for each
-     call,
-     unless the call was cancelled - in which case this can be skipped */
+  /** Send initial metadata: one and only one instance MUST be sent for each
+      call, unless the call was cancelled - in which case this can be skipped */
   GRPC_OP_SEND_INITIAL_METADATA = 0,
-  /* Send a message: 0 or more of these operations can occur for each call */
+  /** Send a message: 0 or more of these operations can occur for each call */
   GRPC_OP_SEND_MESSAGE,
-  /* Send a close from the client: one and only one instance MUST be sent from
-     the client,
-     unless the call was cancelled - in which case this can be skipped */
+  /** Send a close from the client: one and only one instance MUST be sent from
+      the client, unless the call was cancelled - in which case this can be 
+      skipped */
   GRPC_OP_SEND_CLOSE_FROM_CLIENT,
-  /* Send status from the server: one and only one instance MUST be sent from
-     the server
-     unless the call was cancelled - in which case this can be skipped */
+  /** Send status from the server: one and only one instance MUST be sent from
+      the server unless the call was cancelled - in which case this can be 
+      skipped */
   GRPC_OP_SEND_STATUS_FROM_SERVER,
-  /* Receive initial metadata: one and only one MUST be made on the client, must
-     not be made on the server */
+  /** Receive initial metadata: one and only one MUST be made on the client, 
+      must not be made on the server */
   GRPC_OP_RECV_INITIAL_METADATA,
-  /* Receive a message: 0 or more of these operations can occur for each call */
+  /** Receive a message: 0 or more of these operations can occur for each call */
   GRPC_OP_RECV_MESSAGE,
-  /* Receive status on the client: one and only one must be made on the client.
+  /** Receive status on the client: one and only one must be made on the client.
      This operation always succeeds, meaning ops paired with this operation
      will also appear to succeed, even though they may not have. In that case
-     the status will indicate some failure.
-     */
+     the status will indicate some failure. */
   GRPC_OP_RECV_STATUS_ON_CLIENT,
-  /* Receive close on the server: one and only one must be made on the server
-     */
+  /** Receive close on the server: one and only one must be made on the 
+      server */
   GRPC_OP_RECV_CLOSE_ON_SERVER
 } grpc_op_type;
 
-/* Operation data: one field for each op type (except SEND_CLOSE_FROM_CLIENT
-   which has
-   no arguments) */
+/** Operation data: one field for each op type (except SEND_CLOSE_FROM_CLIENT
+   which has no arguments) */
 typedef struct grpc_op {
+  /** Operation type, as defined by grpc_op_type */
   grpc_op_type op;
-  gpr_uint32 flags; /**< Write flags bitset for grpc_begin_messages */
+  /** Write flags bitset for grpc_begin_messages */
+  gpr_uint32 flags; 
   union {
     struct {
       size_t count;
@@ -283,53 +297,49 @@ typedef struct grpc_op {
       grpc_status_code status;
       const char *status_details;
     } send_status_from_server;
-    /* ownership of the array is with the caller, but ownership of the elements
-       stays with the call object (ie key, value members are owned by the call
-       object, recv_initial_metadata->array is owned by the caller).
-       After the operation completes, call grpc_metadata_array_destroy on this
-       value, or reuse it in a future op. */
+    /** ownership of the array is with the caller, but ownership of the elements
+        stays with the call object (ie key, value members are owned by the call
+        object, recv_initial_metadata->array is owned by the caller).
+        After the operation completes, call grpc_metadata_array_destroy on this
+        value, or reuse it in a future op. */
     grpc_metadata_array *recv_initial_metadata;
-    /* ownership of the byte buffer is moved to the caller; the caller must call
-       grpc_byte_buffer_destroy on this value, or reuse it in a future op. */
+    /** ownership of the byte buffer is moved to the caller; the caller must call
+        grpc_byte_buffer_destroy on this value, or reuse it in a future op. */
     grpc_byte_buffer **recv_message;
     struct {
-      /* ownership of the array is with the caller, but ownership of the
-         elements
-         stays with the call object (ie key, value members are owned by the call
-         object, trailing_metadata->array is owned by the caller).
-         After the operation completes, call grpc_metadata_array_destroy on this
-         value, or reuse it in a future op. */
+      /** ownership of the array is with the caller, but ownership of the
+          elements stays with the call object (ie key, value members are owned 
+          by the call object, trailing_metadata->array is owned by the caller).
+          After the operation completes, call grpc_metadata_array_destroy on this
+          value, or reuse it in a future op. */
       grpc_metadata_array *trailing_metadata;
       grpc_status_code *status;
-      /* status_details is a buffer owned by the application before the op
-         completes
-         and after the op has completed. During the operation status_details may
-         be
-         reallocated to a size larger than *status_details_capacity, in which
-         case
-         *status_details_capacity will be updated with the new array capacity.
-
-         Pre-allocating space:
-         size_t my_capacity = 8;
-         char *my_details = gpr_malloc(my_capacity);
-         x.status_details = &my_details;
-         x.status_details_capacity = &my_capacity;
-
-         Not pre-allocating space:
-         size_t my_capacity = 0;
-         char *my_details = NULL;
-         x.status_details = &my_details;
-         x.status_details_capacity = &my_capacity;
-
-         After the call:
-         gpr_free(my_details); */
+      /** status_details is a buffer owned by the application before the op
+          completes and after the op has completed. During the operation
+          status_details may be reallocated to a size larger than 
+          *status_details_capacity, in which case *status_details_capacity will 
+          be updated with the new array capacity.
+
+          Pre-allocating space:
+          size_t my_capacity = 8;
+          char *my_details = gpr_malloc(my_capacity);
+          x.status_details = &my_details;
+          x.status_details_capacity = &my_capacity;
+
+          Not pre-allocating space:
+          size_t my_capacity = 0;
+          char *my_details = NULL;
+          x.status_details = &my_details;
+          x.status_details_capacity = &my_capacity;
+
+          After the call:
+          gpr_free(my_details); */
       char **status_details;
       size_t *status_details_capacity;
     } recv_status_on_client;
     struct {
-      /* out argument, set to 1 if the call failed in any way (seen as a
-         cancellation
-         on the server), or 0 if the call succeeded */
+      /** out argument, set to 1 if the call failed in any way (seen as a
+          cancellation on the server), or 0 if the call succeeded */
       int *cancelled;
     } recv_close_on_server;
   } data;
@@ -379,62 +389,62 @@ grpc_event grpc_completion_queue_next(grpc_completion_queue *cq,
 grpc_event grpc_completion_queue_pluck(grpc_completion_queue *cq, void *tag,
                                        gpr_timespec deadline);
 
-/* Begin destruction of a completion queue. Once all possible events are
-   drained then grpc_completion_queue_next will start to produce
-   GRPC_QUEUE_SHUTDOWN events only. At that point it's safe to call
-   grpc_completion_queue_destroy.
+/** Begin destruction of a completion queue. Once all possible events are
+    drained then grpc_completion_queue_next will start to produce
+    GRPC_QUEUE_SHUTDOWN events only. At that point it's safe to call
+    grpc_completion_queue_destroy.
 
-   After calling this function applications should ensure that no
-   NEW work is added to be published on this completion queue. */
+    After calling this function applications should ensure that no
+    NEW work is added to be published on this completion queue. */
 void grpc_completion_queue_shutdown(grpc_completion_queue *cq);
 
-/* Destroy a completion queue. The caller must ensure that the queue is
-   drained and no threads are executing grpc_completion_queue_next */
+/** Destroy a completion queue. The caller must ensure that the queue is
+    drained and no threads are executing grpc_completion_queue_next */
 void grpc_completion_queue_destroy(grpc_completion_queue *cq);
 
-/* Create a call given a grpc_channel, in order to call 'method'. All
-   completions are sent to 'completion_queue'. 'method' and 'host' need only
-   live through the invocation of this function. */
+/** Create a call given a grpc_channel, in order to call 'method'. All
+    completions are sent to 'completion_queue'. 'method' and 'host' need only
+    live through the invocation of this function. */
 grpc_call *grpc_channel_create_call(grpc_channel *channel,
                                     grpc_completion_queue *completion_queue,
                                     const char *method, const char *host,
                                     gpr_timespec deadline);
 
-/* Pre-register a method/host pair on a channel. */
+/** Pre-register a method/host pair on a channel. */
 void *grpc_channel_register_call(grpc_channel *channel, const char *method,
                                  const char *host);
 
-/* Create a call given a handle returned from grpc_channel_register_call */
+/** Create a call given a handle returned from grpc_channel_register_call */
 grpc_call *grpc_channel_create_registered_call(
     grpc_channel *channel, grpc_completion_queue *completion_queue,
     void *registered_call_handle, gpr_timespec deadline);
 
-/* Start a batch of operations defined in the array ops; when complete, post a
-   completion of type 'tag' to the completion queue bound to the call.
-   The order of ops specified in the batch has no significance.
-   Only one operation of each type can be active at once in any given
-   batch. You must call grpc_completion_queue_next or
-   grpc_completion_queue_pluck on the completion queue associated with 'call'
-   for work to be performed.
-   THREAD SAFETY: access to grpc_call_start_batch in multi-threaded environment
-   needs to be synchronized. As an optimization, you may synchronize batches
-   containing just send operations independently from batches containing just
-   receive operations. */
+/** Start a batch of operations defined in the array ops; when complete, post a
+    completion of type 'tag' to the completion queue bound to the call.
+    The order of ops specified in the batch has no significance.
+    Only one operation of each type can be active at once in any given
+    batch. You must call grpc_completion_queue_next or
+    grpc_completion_queue_pluck on the completion queue associated with 'call'
+    for work to be performed.
+    THREAD SAFETY: access to grpc_call_start_batch in multi-threaded environment
+    needs to be synchronized. As an optimization, you may synchronize batches
+    containing just send operations independently from batches containing just
+    receive operations. */
 grpc_call_error grpc_call_start_batch(grpc_call *call, const grpc_op *ops,
                                       size_t nops, void *tag);
 
-/* Create a client channel to 'target'. Additional channel level configuration
-   MAY be provided by grpc_channel_args, though the expectation is that most
-   clients will want to simply pass NULL. See grpc_channel_args definition for
-   more on this. The data in 'args' need only live through the invocation of
-   this function. */
+/** Create a client channel to 'target'. Additional channel level configuration
+    MAY be provided by grpc_channel_args, though the expectation is that most
+    clients will want to simply pass NULL. See grpc_channel_args definition for
+    more on this. The data in 'args' need only live through the invocation of
+    this function. */
 grpc_channel *grpc_channel_create(const char *target,
                                   const grpc_channel_args *args);
 
-/* Create a lame client: this client fails every operation attempted on it. */
+/** Create a lame client: this client fails every operation attempted on it. */
 grpc_channel *grpc_lame_client_channel_create(void);
 
-/* Close and destroy a grpc channel */
+/** Close and destroy a grpc channel */
 void grpc_channel_destroy(grpc_channel *channel);
 
 /* Error handling for grpc_call
@@ -443,49 +453,49 @@ void grpc_channel_destroy(grpc_channel *channel);
    If a grpc_call fails, it's guaranteed that no change to the call state
    has been made. */
 
-/* Called by clients to cancel an RPC on the server.
-   Can be called multiple times, from any thread.
-   THREAD-SAFETY grpc_call_cancel and grpc_call_cancel_with_status
-   are thread-safe, and can be called at any point before grpc_call_destroy
-   is called.*/
+/** Called by clients to cancel an RPC on the server.
+    Can be called multiple times, from any thread.
+    THREAD-SAFETY grpc_call_cancel and grpc_call_cancel_with_status
+    are thread-safe, and can be called at any point before grpc_call_destroy
+    is called.*/
 grpc_call_error grpc_call_cancel(grpc_call *call);
 
-/* Called by clients to cancel an RPC on the server.
-   Can be called multiple times, from any thread.
-   If a status has not been received for the call, set it to the status code
-   and description passed in.
-   Importantly, this function does not send status nor description to the
-   remote endpoint. */
+/** Called by clients to cancel an RPC on the server.
+    Can be called multiple times, from any thread.
+    If a status has not been received for the call, set it to the status code
+    and description passed in.
+    Importantly, this function does not send status nor description to the
+    remote endpoint. */
 grpc_call_error grpc_call_cancel_with_status(grpc_call *call,
                                              grpc_status_code status,
                                              const char *description);
 
-/* Destroy a call.
-   THREAD SAFETY: grpc_call_destroy is thread-compatible */
+/** Destroy a call.
+    THREAD SAFETY: grpc_call_destroy is thread-compatible */
 void grpc_call_destroy(grpc_call *call);
 
-/* Request notification of a new call. 'cq_for_notification' must
-   have been registered to the server via grpc_server_register_completion_queue.
-   */
+/** Request notification of a new call. 'cq_for_notification' must
+    have been registered to the server via 
+    grpc_server_register_completion_queue. */
 grpc_call_error grpc_server_request_call(
     grpc_server *server, grpc_call **call, grpc_call_details *details,
     grpc_metadata_array *request_metadata,
     grpc_completion_queue *cq_bound_to_call,
     grpc_completion_queue *cq_for_notification, void *tag_new);
 
-/* Registers a method in the server.
-   Methods to this (host, method) pair will not be reported by
-   grpc_server_request_call, but instead be reported by
-   grpc_server_request_registered_call when passed the appropriate
-   registered_method (as returned by this function).
-   Must be called before grpc_server_start.
-   Returns NULL on failure. */
+/** Registers a method in the server.
+    Methods to this (host, method) pair will not be reported by
+    grpc_server_request_call, but instead be reported by
+    grpc_server_request_registered_call when passed the appropriate
+    registered_method (as returned by this function).
+    Must be called before grpc_server_start.
+    Returns NULL on failure. */
 void *grpc_server_register_method(grpc_server *server, const char *method,
                                   const char *host);
 
-/* Request notification of a new pre-registered call. 'cq_for_notification' must
-   have been registered to the server via grpc_server_register_completion_queue.
-   */
+/** Request notification of a new pre-registered call. 'cq_for_notification' 
+    must have been registered to the server via 
+    grpc_server_register_completion_queue. */
 grpc_call_error grpc_server_request_registered_call(
     grpc_server *server, void *registered_method, grpc_call **call,
     gpr_timespec *deadline, grpc_metadata_array *request_metadata,
@@ -493,45 +503,45 @@ grpc_call_error grpc_server_request_registered_call(
     grpc_completion_queue *cq_bound_to_call,
     grpc_completion_queue *cq_for_notification, void *tag_new);
 
-/* Create a server. Additional configuration for each incoming channel can
-   be specified with args. If no additional configuration is needed, args can
-   be NULL. See grpc_channel_args for more. The data in 'args' need only live
-   through the invocation of this function. */
+/** Create a server. Additional configuration for each incoming channel can
+    be specified with args. If no additional configuration is needed, args can
+    be NULL. See grpc_channel_args for more. The data in 'args' need only live
+    through the invocation of this function. */
 grpc_server *grpc_server_create(const grpc_channel_args *args);
 
-/* Register a completion queue with the server. Must be done for any
-   notification completion queue that is passed to grpc_server_request_*_call
-   and to grpc_server_shutdown_and_notify. Must be performed prior to
-   grpc_server_start. */
+/** Register a completion queue with the server. Must be done for any
+    notification completion queue that is passed to grpc_server_request_*_call
+    and to grpc_server_shutdown_and_notify. Must be performed prior to
+    grpc_server_start. */
 void grpc_server_register_completion_queue(grpc_server *server,
                                            grpc_completion_queue *cq);
 
-/* Add a HTTP2 over plaintext over tcp listener.
-   Returns bound port number on success, 0 on failure.
-   REQUIRES: server not started */
+/** Add a HTTP2 over plaintext over tcp listener.
+    Returns bound port number on success, 0 on failure.
+    REQUIRES: server not started */
 int grpc_server_add_http2_port(grpc_server *server, const char *addr);
 
-/* Start a server - tells all listeners to start listening */
+/** Start a server - tells all listeners to start listening */
 void grpc_server_start(grpc_server *server);
 
-/* Begin shutting down a server.
-   After completion, no new calls or connections will be admitted.
-   Existing calls will be allowed to complete.
-   Send a GRPC_OP_COMPLETE event when there are no more calls being serviced.
-   Shutdown is idempotent, and all tags will be notified at once if multiple
-   grpc_server_shutdown_and_notify calls are made. 'cq' must have been
-   registered to this server via grpc_server_register_completion_queue. */
+/** Begin shutting down a server.
+    After completion, no new calls or connections will be admitted.
+    Existing calls will be allowed to complete.
+    Send a GRPC_OP_COMPLETE event when there are no more calls being serviced.
+    Shutdown is idempotent, and all tags will be notified at once if multiple
+    grpc_server_shutdown_and_notify calls are made. 'cq' must have been
+    registered to this server via grpc_server_register_completion_queue. */
 void grpc_server_shutdown_and_notify(grpc_server *server,
                                      grpc_completion_queue *cq, void *tag);
 
-/* Cancel all in-progress calls.
-   Only usable after shutdown. */
+/** Cancel all in-progress calls.
+    Only usable after shutdown. */
 void grpc_server_cancel_all_calls(grpc_server *server);
 
-/* Destroy a server.
-   Shutdown must have completed beforehand (i.e. all tags generated by
-   grpc_server_shutdown_and_notify must have been received, and at least
-   one call to grpc_server_shutdown_and_notify must have been made). */
+/** Destroy a server.
+    Shutdown must have completed beforehand (i.e. all tags generated by
+    grpc_server_shutdown_and_notify must have been received, and at least
+    one call to grpc_server_shutdown_and_notify must have been made). */
 void grpc_server_destroy(grpc_server *server);
 
 /** Enable or disable a tracer.
diff --git a/include/grpc/support/port_platform.h b/include/grpc/support/port_platform.h
index a5d1b62702..57fed18cf6 100644
--- a/include/grpc/support/port_platform.h
+++ b/include/grpc/support/port_platform.h
@@ -71,6 +71,7 @@
 
 #if !defined(GPR_NO_AUTODETECT_PLATFORM)
 #if defined(_WIN64) || defined(WIN64)
+#define GPR_PLATFORM_STRING "windows"
 #define GPR_WIN32 1
 #define GPR_ARCH_64 1
 #define GPR_GETPID_IN_PROCESS_H 1
@@ -84,6 +85,7 @@
 #endif
 #define GPR_WINDOWS_CRASH_HANDLER 1
 #elif defined(_WIN32) || defined(WIN32)
+#define GPR_PLATFORM_STRING "windows"
 #define GPR_ARCH_32 1
 #define GPR_WIN32 1
 #define GPR_GETPID_IN_PROCESS_H 1
@@ -97,6 +99,7 @@
 #endif
 #define GPR_WINDOWS_CRASH_HANDLER 1
 #elif defined(ANDROID) || defined(__ANDROID__)
+#define GPR_PLATFORM_STRING "android"
 #define GPR_ANDROID 1
 #define GPR_ARCH_32 1
 #define GPR_CPU_LINUX 1
@@ -117,6 +120,7 @@
 #define GPR_GETPID_IN_UNISTD_H 1
 #define GPR_HAVE_MSG_NOSIGNAL 1
 #elif defined(__linux__)
+#define GPR_PLATFORM_STRING "linux"
 #ifndef _BSD_SOURCE
 #define _BSD_SOURCE
 #endif
@@ -173,9 +177,11 @@
 #define _BSD_SOURCE
 #endif
 #if TARGET_OS_IPHONE
+#define GPR_PLATFORM_STRING "ios"
 #define GPR_CPU_IPHONE 1
 #define GPR_PTHREAD_TLS 1
 #else /* TARGET_OS_IPHONE */
+#define GPR_PLATFORM_STRING "osx"
 #define GPR_CPU_POSIX 1
 #define GPR_GCC_TLS 1
 #endif
@@ -201,6 +207,7 @@
 #define GPR_ARCH_32 1
 #endif /* _LP64 */
 #elif defined(__FreeBSD__)
+#define GPR_PLATFORM_STRING "freebsd"
 #ifndef _BSD_SOURCE
 #define _BSD_SOURCE
 #endif
@@ -232,6 +239,11 @@
 #endif
 #endif /* GPR_NO_AUTODETECT_PLATFORM */
 
+#ifndef GPR_PLATFORM_STRING
+#warning "GPR_PLATFORM_STRING not auto-detected"
+#define GPR_PLATFORM_STRING "unknown"
+#endif
+
 /* For a common case, assume that the platform has a C99-like stdint.h */
 
 #include <stdint.h>
diff --git a/include/grpc/support/time.h b/include/grpc/support/time.h
index 3f375f6ecd..be59c37956 100644
--- a/include/grpc/support/time.h
+++ b/include/grpc/support/time.h
@@ -83,6 +83,9 @@ void gpr_time_init(void);
 /* Return the current time measured from the given clocks epoch. */
 gpr_timespec gpr_now(gpr_clock_type clock);
 
+/* Convert a timespec from one clock to another */
+gpr_timespec gpr_convert_clock_type(gpr_timespec t, gpr_clock_type target_clock);
+
 /* Return -ve, 0, or +ve according to whether a < b, a == b, or a > b
    respectively.  */
 int gpr_time_cmp(gpr_timespec a, gpr_timespec b);
diff --git a/src/compiler/csharp_generator.cc b/src/compiler/csharp_generator.cc
index 1910e9bd2d..64371047e0 100644
--- a/src/compiler/csharp_generator.cc
+++ b/src/compiler/csharp_generator.cc
@@ -149,7 +149,7 @@ std::string GetMethodRequestParamMaybe(const MethodDescriptor *method) {
 std::string GetMethodReturnTypeClient(const MethodDescriptor *method) {
   switch (GetMethodType(method)) {
     case METHODTYPE_NO_STREAMING:
-      return "Task<" + GetClassName(method->output_type()) + ">";
+      return "AsyncUnaryCall<" + GetClassName(method->output_type()) + ">";
     case METHODTYPE_CLIENT_STREAMING:
       return "AsyncClientStreamingCall<" + GetClassName(method->input_type())
           + ", " + GetClassName(method->output_type()) + ">";
@@ -298,7 +298,7 @@ void GenerateServerInterface(Printer* out, const ServiceDescriptor *service) {
   out->Indent();
   for (int i = 0; i < service->method_count(); i++) {
     const MethodDescriptor *method = service->method(i);
-    out->Print("$returntype$ $methodname$(ServerCallContext context, $request$$response_stream_maybe$);\n",
+    out->Print("$returntype$ $methodname$($request$$response_stream_maybe$, ServerCallContext context);\n",
                "methodname", method->name(), "returntype",
                GetMethodReturnTypeServer(method), "request",
                GetMethodRequestParamServer(method), "response_stream_maybe",
diff --git a/src/compiler/objective_c_generator.cc b/src/compiler/objective_c_generator.cc
index 711d0d5870..69b3805bb1 100644
--- a/src/compiler/objective_c_generator.cc
+++ b/src/compiler/objective_c_generator.cc
@@ -186,9 +186,6 @@ string GetHeader(const ServiceDescriptor *service) {
     grpc::protobuf::io::StringOutputStream output_stream(&output);
     Printer printer(&output_stream, '$');
 
-    printer.Print("@protocol GRXWriteable;\n");
-    printer.Print("@protocol GRXWriter;\n\n");
-
     map<string, string> vars = {{"service_class", ServiceClassName(service)}};
 
     printer.Print(vars, "@protocol $service_class$ <NSObject>\n\n");
diff --git a/src/compiler/objective_c_plugin.cc b/src/compiler/objective_c_plugin.cc
index 2b5ab758fc..10f06ad4df 100644
--- a/src/compiler/objective_c_plugin.cc
+++ b/src/compiler/objective_c_plugin.cc
@@ -63,7 +63,9 @@ class ObjectiveCGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
       // Generate .pbrpc.h
 
       string imports = string("#import \"") + file_name + ".pbobjc.h\"\n\n"
-        "#import <ProtoRPC/ProtoService.h>\n";
+        "#import <ProtoRPC/ProtoService.h>\n"
+        "#import <RxLibrary/GRXWriteable.h>\n"
+        "#import <RxLibrary/GRXWriter.h>\n";
 
       // TODO(jcanizales): Instead forward-declare the input and output types
       // and import the files in the .pbrpc.m
@@ -89,7 +91,6 @@ class ObjectiveCGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
 
       string imports = string("#import \"") + file_name + ".pbrpc.h\"\n\n"
         "#import <ProtoRPC/ProtoRPC.h>\n"
-        "#import <RxLibrary/GRXWriteable.h>\n"
         "#import <RxLibrary/GRXWriter+Immediate.h>\n";
 
       string definitions;
diff --git a/src/core/channel/client_channel.c b/src/core/channel/client_channel.c
index 10e01ebbb4..c1aa580b2d 100644
--- a/src/core/channel/client_channel.c
+++ b/src/core/channel/client_channel.c
@@ -236,21 +236,6 @@ static void picked_target(void *arg, int iomgr_success) {
   }
 }
 
-static void pick_target(grpc_lb_policy *lb_policy, call_data *calld) {
-  grpc_metadata_batch *initial_metadata;
-  grpc_transport_stream_op *op = &calld->waiting_op;
-
-  GPR_ASSERT(op->bind_pollset);
-  GPR_ASSERT(op->send_ops);
-  GPR_ASSERT(op->send_ops->nops >= 1);
-  GPR_ASSERT(op->send_ops->ops[0].type == GRPC_OP_METADATA);
-  initial_metadata = &op->send_ops->ops[0].data.metadata;
-
-  grpc_iomgr_closure_init(&calld->async_setup_task, picked_target, calld);
-  grpc_lb_policy_pick(lb_policy, op->bind_pollset, initial_metadata,
-                      &calld->picked_channel, &calld->async_setup_task);
-}
-
 static grpc_iomgr_closure *merge_into_waiting_op(
     grpc_call_element *elem, grpc_transport_stream_op *new_op) {
   call_data *calld = elem->call_data;
@@ -358,12 +343,23 @@ static void perform_transport_stream_op(grpc_call_element *elem,
           gpr_mu_lock(&chand->mu_config);
           lb_policy = chand->lb_policy;
           if (lb_policy) {
+            grpc_transport_stream_op *op = &calld->waiting_op;
+            grpc_pollset *bind_pollset = op->bind_pollset;
+            grpc_metadata_batch *initial_metadata = &op->send_ops->ops[0].data.metadata;
             GRPC_LB_POLICY_REF(lb_policy, "pick");
             gpr_mu_unlock(&chand->mu_config);
             calld->state = CALL_WAITING_FOR_PICK;
+
+            GPR_ASSERT(op->bind_pollset);
+            GPR_ASSERT(op->send_ops);
+            GPR_ASSERT(op->send_ops->nops >= 1);
+            GPR_ASSERT(
+                op->send_ops->ops[0].type == GRPC_OP_METADATA);
             gpr_mu_unlock(&calld->mu_state);
 
-            pick_target(lb_policy, calld);
+            grpc_iomgr_closure_init(&calld->async_setup_task, picked_target, calld);
+            grpc_lb_policy_pick(lb_policy, bind_pollset, initial_metadata,
+                                &calld->picked_channel, &calld->async_setup_task);
 
             GRPC_LB_POLICY_UNREF(lb_policy, "pick");
           } else if (chand->resolver != NULL) {
diff --git a/src/core/channel/compress_filter.c b/src/core/channel/compress_filter.c
index 9ff679df18..f656484fac 100644
--- a/src/core/channel/compress_filter.c
+++ b/src/core/channel/compress_filter.c
@@ -208,7 +208,7 @@ static void process_send_ops(grpc_call_element *elem,
             calld->has_compression_algorithm = 1; /* GPR_TRUE */
           }
           /* hint compression algorithm */
-          grpc_metadata_batch_add_head(
+          grpc_metadata_batch_add_tail(
               &(sop->data.metadata), &calld->compression_algorithm_storage,
               GRPC_MDELEM_REF(channeld->mdelem_compression_algorithms
                                   [calld->compression_algorithm]));
diff --git a/src/core/channel/http_client_filter.c b/src/core/channel/http_client_filter.c
index 63e4912397..6e93103a6a 100644
--- a/src/core/channel/http_client_filter.c
+++ b/src/core/channel/http_client_filter.c
@@ -32,13 +32,17 @@
 
 #include "src/core/channel/http_client_filter.h"
 #include <string.h>
+#include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+#include "src/core/support/string.h"
 
 typedef struct call_data {
   grpc_linked_mdelem method;
   grpc_linked_mdelem scheme;
   grpc_linked_mdelem te_trailers;
   grpc_linked_mdelem content_type;
+  grpc_linked_mdelem user_agent;
   int sent_initial_metadata;
 
   int got_initial_metadata;
@@ -58,6 +62,8 @@ typedef struct channel_data {
   grpc_mdelem *scheme;
   grpc_mdelem *content_type;
   grpc_mdelem *status;
+  /** complete user agent mdelem */
+  grpc_mdelem *user_agent;
 } channel_data;
 
 /* used to silence 'variable not used' warnings */
@@ -92,6 +98,18 @@ static void hc_on_recv(void *user_data, int success) {
   calld->on_done_recv->cb(calld->on_done_recv->cb_arg, success);
 }
 
+static grpc_mdelem *client_strip_filter(void *user_data, grpc_mdelem *md) {
+  grpc_call_element *elem = user_data;
+  channel_data *channeld = elem->channel_data;
+  /* eat the things we'd like to set ourselves */
+  if (md->key == channeld->method->key) return NULL;
+  if (md->key == channeld->scheme->key) return NULL;
+  if (md->key == channeld->te_trailers->key) return NULL;
+  if (md->key == channeld->content_type->key) return NULL;
+  if (md->key == channeld->user_agent->key) return NULL;
+  return md;
+}
+
 static void hc_mutate_op(grpc_call_element *elem,
                          grpc_transport_stream_op *op) {
   /* grab pointers to our data from the call element */
@@ -105,6 +123,7 @@ static void hc_mutate_op(grpc_call_element *elem,
       grpc_stream_op *op = &ops[i];
       if (op->type != GRPC_OP_METADATA) continue;
       calld->sent_initial_metadata = 1;
+      grpc_metadata_batch_filter(&op->data.metadata, client_strip_filter, elem);
       /* Send : prefixed headers, which have to be before any application
          layer headers. */
       grpc_metadata_batch_add_head(&op->data.metadata, &calld->method,
@@ -115,6 +134,8 @@ static void hc_mutate_op(grpc_call_element *elem,
                                    GRPC_MDELEM_REF(channeld->te_trailers));
       grpc_metadata_batch_add_tail(&op->data.metadata, &calld->content_type,
                                    GRPC_MDELEM_REF(channeld->content_type));
+      grpc_metadata_batch_add_tail(&op->data.metadata, &calld->user_agent,
+                                   GRPC_MDELEM_REF(channeld->user_agent));
       break;
     }
   }
@@ -169,6 +190,55 @@ static const char *scheme_from_args(const grpc_channel_args *args) {
   return "http";
 }
 
+static grpc_mdstr *user_agent_from_args(grpc_mdctx *mdctx,
+                                        const grpc_channel_args *args) {
+  gpr_strvec v;
+  size_t i;
+  int is_first = 1;
+  char *tmp;
+  grpc_mdstr *result;
+
+  gpr_strvec_init(&v);
+
+  for (i = 0; args && i < args->num_args; i++) {
+    if (0 == strcmp(args->args[i].key, GRPC_ARG_PRIMARY_USER_AGENT_STRING)) {
+      if (args->args[i].type != GRPC_ARG_STRING) {
+        gpr_log(GPR_ERROR, "Channel argument '%s' should be a string",
+                GRPC_ARG_PRIMARY_USER_AGENT_STRING);
+      } else {
+        if (!is_first) gpr_strvec_add(&v, gpr_strdup(" "));
+        is_first = 0;
+        gpr_strvec_add(&v, gpr_strdup(args->args[i].value.string));
+      }
+    }
+  }
+
+  gpr_asprintf(&tmp, "%sgrpc-c/%s (%s)", is_first ? "" : " ",
+               grpc_version_string(), GPR_PLATFORM_STRING);
+  is_first = 0;
+  gpr_strvec_add(&v, tmp);
+
+  for (i = 0; args && i < args->num_args; i++) {
+    if (0 == strcmp(args->args[i].key, GRPC_ARG_SECONDARY_USER_AGENT_STRING)) {
+      if (args->args[i].type != GRPC_ARG_STRING) {
+        gpr_log(GPR_ERROR, "Channel argument '%s' should be a string",
+                GRPC_ARG_SECONDARY_USER_AGENT_STRING);
+      } else {
+        if (!is_first) gpr_strvec_add(&v, gpr_strdup(" "));
+        is_first = 0;
+        gpr_strvec_add(&v, gpr_strdup(args->args[i].value.string));
+      }
+    }
+  }
+
+  tmp = gpr_strvec_flatten(&v, NULL);
+  gpr_strvec_destroy(&v);
+  result = grpc_mdstr_from_string(mdctx, tmp);
+  gpr_free(tmp);
+
+  return result;
+}
+
 /* Constructor for channel_data */
 static void init_channel_elem(grpc_channel_element *elem, grpc_channel *master,
                               const grpc_channel_args *args, grpc_mdctx *mdctx,
@@ -189,6 +259,9 @@ static void init_channel_elem(grpc_channel_element *elem, grpc_channel *master,
   channeld->content_type =
       grpc_mdelem_from_strings(mdctx, "content-type", "application/grpc");
   channeld->status = grpc_mdelem_from_strings(mdctx, ":status", "200");
+  channeld->user_agent = grpc_mdelem_from_metadata_strings(
+      mdctx, grpc_mdstr_from_string(mdctx, "user-agent"),
+      user_agent_from_args(mdctx, args));
 }
 
 /* Destructor for channel data */
@@ -201,6 +274,7 @@ static void destroy_channel_elem(grpc_channel_element *elem) {
   GRPC_MDELEM_UNREF(channeld->scheme);
   GRPC_MDELEM_UNREF(channeld->content_type);
   GRPC_MDELEM_UNREF(channeld->status);
+  GRPC_MDELEM_UNREF(channeld->user_agent);
 }
 
 const grpc_channel_filter grpc_http_client_filter = {
diff --git a/src/core/client_config/subchannel.c b/src/core/client_config/subchannel.c
index 35f172683a..487f5afb35 100644
--- a/src/core/client_config/subchannel.c
+++ b/src/core/client_config/subchannel.c
@@ -300,7 +300,7 @@ static void continue_connect(grpc_subchannel *c) {
 }
 
 static void start_connect(grpc_subchannel *c) {
-  gpr_timespec now = gpr_now(GPR_CLOCK_REALTIME);
+  gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
   c->next_attempt = now;
   c->backoff_delta = gpr_time_from_seconds(1, GPR_TIMESPAN);
 
@@ -585,7 +585,7 @@ static void subchannel_connected(void *arg, int iomgr_success) {
     c->have_alarm = 1;
     c->next_attempt = gpr_time_add(c->next_attempt, c->backoff_delta);
     c->backoff_delta = gpr_time_add(c->backoff_delta, c->backoff_delta);
-    grpc_alarm_init(&c->alarm, c->next_attempt, on_alarm, c, gpr_now(GPR_CLOCK_REALTIME));
+    grpc_alarm_init(&c->alarm, c->next_attempt, on_alarm, c, gpr_now(GPR_CLOCK_MONOTONIC));
     gpr_mu_unlock(&c->mu);
   }
 }
diff --git a/src/core/iomgr/alarm.c b/src/core/iomgr/alarm.c
index 5b9a37e5dd..931f746f75 100644
--- a/src/core/iomgr/alarm.c
+++ b/src/core/iomgr/alarm.c
@@ -36,6 +36,7 @@
 #include "src/core/iomgr/alarm_heap.h"
 #include "src/core/iomgr/alarm_internal.h"
 #include "src/core/iomgr/time_averaged_stats.h"
+#include <grpc/support/log.h>
 #include <grpc/support/sync.h>
 #include <grpc/support/useful.h>
 
@@ -67,6 +68,7 @@ typedef struct {
 static gpr_mu g_mu;
 /* Allow only one run_some_expired_alarms at once */
 static gpr_mu g_checker_mu;
+static gpr_clock_type g_clock_type;
 static shard_type g_shards[NUM_SHARDS];
 /* Protected by g_mu */
 static shard_type *g_shard_queue[NUM_SHARDS];
@@ -85,6 +87,7 @@ void grpc_alarm_list_init(gpr_timespec now) {
 
   gpr_mu_init(&g_mu);
   gpr_mu_init(&g_checker_mu);
+  g_clock_type = now.clock_type;
 
   for (i = 0; i < NUM_SHARDS; i++) {
     shard_type *shard = &g_shards[i];
@@ -102,7 +105,7 @@ void grpc_alarm_list_init(gpr_timespec now) {
 
 void grpc_alarm_list_shutdown(void) {
   int i;
-  while (run_some_expired_alarms(NULL, gpr_inf_future(GPR_CLOCK_REALTIME), NULL,
+  while (run_some_expired_alarms(NULL, gpr_inf_future(g_clock_type), NULL,
                                  0))
     ;
   for (i = 0; i < NUM_SHARDS; i++) {
@@ -175,6 +178,8 @@ void grpc_alarm_init(grpc_alarm *alarm, gpr_timespec deadline,
                      gpr_timespec now) {
   int is_first_alarm = 0;
   shard_type *shard = &g_shards[shard_idx(alarm)];
+  GPR_ASSERT(deadline.clock_type == g_clock_type);
+  GPR_ASSERT(now.clock_type == g_clock_type);
   alarm->cb = alarm_cb;
   alarm->cb_arg = alarm_cb_arg;
   alarm->deadline = deadline;
@@ -355,6 +360,7 @@ static int run_some_expired_alarms(gpr_mu *drop_mu, gpr_timespec now,
 }
 
 int grpc_alarm_check(gpr_mu *drop_mu, gpr_timespec now, gpr_timespec *next) {
+  GPR_ASSERT(now.clock_type == g_clock_type);
   return run_some_expired_alarms(drop_mu, now, next, 1);
 }
 
diff --git a/src/core/iomgr/iomgr.c b/src/core/iomgr/iomgr.c
index 0244f689b1..a18c176b30 100644
--- a/src/core/iomgr/iomgr.c
+++ b/src/core/iomgr/iomgr.c
@@ -57,9 +57,9 @@ static grpc_iomgr_object g_root_object;
 static void background_callback_executor(void *ignored) {
   gpr_mu_lock(&g_mu);
   while (!g_shutdown) {
-    gpr_timespec deadline = gpr_inf_future(GPR_CLOCK_REALTIME);
+    gpr_timespec deadline = gpr_inf_future(GPR_CLOCK_MONOTONIC);
     gpr_timespec short_deadline = gpr_time_add(
-        gpr_now(GPR_CLOCK_REALTIME), gpr_time_from_millis(100, GPR_TIMESPAN));
+        gpr_now(GPR_CLOCK_MONOTONIC), gpr_time_from_millis(100, GPR_TIMESPAN));
     if (g_cbs_head) {
       grpc_iomgr_closure *closure = g_cbs_head;
       g_cbs_head = closure->next;
@@ -67,7 +67,7 @@ static void background_callback_executor(void *ignored) {
       gpr_mu_unlock(&g_mu);
       closure->cb(closure->cb_arg, closure->success);
       gpr_mu_lock(&g_mu);
-    } else if (grpc_alarm_check(&g_mu, gpr_now(GPR_CLOCK_REALTIME),
+    } else if (grpc_alarm_check(&g_mu, gpr_now(GPR_CLOCK_MONOTONIC),
                                 &deadline)) {
     } else {
       gpr_mu_unlock(&g_mu);
@@ -90,7 +90,7 @@ void grpc_iomgr_init(void) {
   gpr_thd_id id;
   gpr_mu_init(&g_mu);
   gpr_cv_init(&g_rcv);
-  grpc_alarm_list_init(gpr_now(GPR_CLOCK_REALTIME));
+  grpc_alarm_list_init(gpr_now(GPR_CLOCK_MONOTONIC));
   g_root_object.next = g_root_object.prev = &g_root_object;
   g_root_object.name = "root";
   grpc_iomgr_platform_init();
@@ -145,7 +145,7 @@ void grpc_iomgr_shutdown(void) {
       } while (g_cbs_head);
       continue;
     }
-    if (grpc_alarm_check(&g_mu, gpr_inf_future(GPR_CLOCK_REALTIME), NULL)) {
+    if (grpc_alarm_check(&g_mu, gpr_inf_future(GPR_CLOCK_MONOTONIC), NULL)) {
       gpr_log(GPR_DEBUG, "got late alarm");
       continue;
     }
diff --git a/src/core/iomgr/pollset_posix.c b/src/core/iomgr/pollset_posix.c
index efb301d81c..c8646af615 100644
--- a/src/core/iomgr/pollset_posix.c
+++ b/src/core/iomgr/pollset_posix.c
@@ -136,7 +136,7 @@ static void finish_shutdown(grpc_pollset *pollset) {
 
 int grpc_pollset_work(grpc_pollset *pollset, gpr_timespec deadline) {
   /* pollset->mu already held */
-  gpr_timespec now = gpr_now(GPR_CLOCK_REALTIME);
+  gpr_timespec now = gpr_now(GPR_CLOCK_MONOTONIC);
   if (gpr_time_cmp(now, deadline) > 0) {
     return 0;
   }
@@ -205,7 +205,7 @@ int grpc_poll_deadline_to_millis_timeout(gpr_timespec deadline,
                                          gpr_timespec now) {
   gpr_timespec timeout;
   static const int max_spin_polling_us = 10;
-  if (gpr_time_cmp(deadline, gpr_inf_future(GPR_CLOCK_REALTIME)) == 0) {
+  if (gpr_time_cmp(deadline, gpr_inf_future(deadline.clock_type)) == 0) {
     return -1;
   }
   if (gpr_time_cmp(deadline, gpr_time_add(now, gpr_time_from_micros(
diff --git a/src/core/iomgr/pollset_windows.c b/src/core/iomgr/pollset_windows.c
index 24226cc980..a9c4739c7c 100644
--- a/src/core/iomgr/pollset_windows.c
+++ b/src/core/iomgr/pollset_windows.c
@@ -70,7 +70,7 @@ void grpc_pollset_destroy(grpc_pollset *pollset) {
 
 int grpc_pollset_work(grpc_pollset *pollset, gpr_timespec deadline) {
   gpr_timespec now;
-  now = gpr_now(GPR_CLOCK_REALTIME);
+  now = gpr_now(GPR_CLOCK_MONOTONIC);
   if (gpr_time_cmp(now, deadline) > 0) {
     return 0 /* GPR_FALSE */;
   }
diff --git a/src/core/iomgr/tcp_client_posix.c b/src/core/iomgr/tcp_client_posix.c
index dc0489e64f..41d8b169e0 100644
--- a/src/core/iomgr/tcp_client_posix.c
+++ b/src/core/iomgr/tcp_client_posix.c
@@ -114,6 +114,8 @@ static void on_writable(void *acp, int success) {
   void (*cb)(void *arg, grpc_endpoint *tcp) = ac->cb;
   void *cb_arg = ac->cb_arg;
 
+  grpc_alarm_cancel(&ac->alarm);
+
   gpr_mu_lock(&ac->mu);
   if (success) {
     do {
@@ -178,8 +180,6 @@ finish:
   if (done) {
     gpr_mu_destroy(&ac->mu);
     gpr_free(ac);
-  } else {
-    grpc_alarm_cancel(&ac->alarm);
   }
   cb(cb_arg, ep);
 }
@@ -253,8 +253,8 @@ void grpc_tcp_client_connect(void (*cb)(void *arg, grpc_endpoint *ep),
   ac->write_closure.cb_arg = ac;
 
   gpr_mu_lock(&ac->mu);
-  grpc_alarm_init(&ac->alarm, deadline, on_alarm, ac,
-                  gpr_now(GPR_CLOCK_REALTIME));
+  grpc_alarm_init(&ac->alarm, gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC), 
+                  on_alarm, ac, gpr_now(GPR_CLOCK_MONOTONIC));
   grpc_fd_notify_on_write(ac->fd, &ac->write_closure);
   gpr_mu_unlock(&ac->mu);
 
diff --git a/src/core/iomgr/tcp_client_windows.c b/src/core/iomgr/tcp_client_windows.c
index 16741452b9..39fd43130b 100644
--- a/src/core/iomgr/tcp_client_windows.c
+++ b/src/core/iomgr/tcp_client_windows.c
@@ -216,7 +216,7 @@ void grpc_tcp_client_connect(void (*cb)(void *arg, grpc_endpoint *tcp),
   ac->aborted = 0;
 
   grpc_alarm_init(&ac->alarm, deadline, on_alarm, ac,
-                  gpr_now(GPR_CLOCK_REALTIME));
+                  gpr_now(GPR_CLOCK_MONOTONIC));
   socket->write_info.outstanding = 1;
   grpc_socket_notify_on_write(socket, on_connect, ac);
   return;
diff --git a/src/core/support/sync_posix.c b/src/core/support/sync_posix.c
index 41af8ceb0a..61572b9a8e 100644
--- a/src/core/support/sync_posix.c
+++ b/src/core/support/sync_posix.c
@@ -63,10 +63,11 @@ void gpr_cv_destroy(gpr_cv *cv) { GPR_ASSERT(pthread_cond_destroy(cv) == 0); }
 
 int gpr_cv_wait(gpr_cv *cv, gpr_mu *mu, gpr_timespec abs_deadline) {
   int err = 0;
-  if (gpr_time_cmp(abs_deadline, gpr_inf_future(GPR_CLOCK_REALTIME)) == 0) {
+  if (gpr_time_cmp(abs_deadline, gpr_inf_future(abs_deadline.clock_type)) == 0) {
     err = pthread_cond_wait(cv, mu);
   } else {
     struct timespec abs_deadline_ts;
+    abs_deadline = gpr_convert_clock_type(abs_deadline, GPR_CLOCK_REALTIME);
     abs_deadline_ts.tv_sec = abs_deadline.tv_sec;
     abs_deadline_ts.tv_nsec = abs_deadline.tv_nsec;
     err = pthread_cond_timedwait(cv, mu, &abs_deadline_ts);
diff --git a/src/core/support/sync_win32.c b/src/core/support/sync_win32.c
index 63196d10d3..54f84a46ac 100644
--- a/src/core/support/sync_win32.c
+++ b/src/core/support/sync_win32.c
@@ -83,10 +83,10 @@ int gpr_cv_wait(gpr_cv *cv, gpr_mu *mu, gpr_timespec abs_deadline) {
   int timeout = 0;
   DWORD timeout_max_ms;
   mu->locked = 0;
-  if (gpr_time_cmp(abs_deadline, gpr_inf_future(GPR_CLOCK_REALTIME)) == 0) {
+  if (gpr_time_cmp(abs_deadline, gpr_inf_future(abs_deadline.clock_type)) == 0) {
     SleepConditionVariableCS(cv, &mu->cs, INFINITE);
   } else {
-    gpr_timespec now = gpr_now(GPR_CLOCK_REALTIME);
+    gpr_timespec now = gpr_now(abs_deadline.clock_type);
     gpr_int64 now_ms = now.tv_sec * 1000 + now.tv_nsec / 1000000;
     gpr_int64 deadline_ms =
         abs_deadline.tv_sec * 1000 + abs_deadline.tv_nsec / 1000000;
diff --git a/src/core/support/time.c b/src/core/support/time.c
index 570f195bd1..b523ae01cc 100644
--- a/src/core/support/time.c
+++ b/src/core/support/time.c
@@ -290,3 +290,30 @@ gpr_int32 gpr_time_to_millis(gpr_timespec t) {
 double gpr_timespec_to_micros(gpr_timespec t) {
   return (double)t.tv_sec * GPR_US_PER_SEC + t.tv_nsec * 1e-3;
 }
+
+gpr_timespec gpr_convert_clock_type(gpr_timespec t, gpr_clock_type clock_type) {
+  if (t.clock_type == clock_type) {
+    return t;
+  }
+
+  if (t.tv_nsec == 0) {
+    if (t.tv_sec == TYPE_MAX(time_t)) {
+      t.clock_type = clock_type;
+      return t;
+    }
+    if (t.tv_sec == TYPE_MIN(time_t)) {
+      t.clock_type = clock_type;
+      return t;
+    }
+  }
+
+  if (clock_type == GPR_TIMESPAN) {
+    return gpr_time_sub(t, gpr_now(t.clock_type));
+  }
+
+  if (t.clock_type == GPR_TIMESPAN) {
+    return gpr_time_add(gpr_now(clock_type), t);
+  }
+
+  return gpr_time_add(gpr_now(clock_type), gpr_time_sub(t, gpr_now(t.clock_type)));
+}
diff --git a/src/core/support/time_posix.c b/src/core/support/time_posix.c
index 258b2e640e..841485c4b4 100644
--- a/src/core/support/time_posix.c
+++ b/src/core/support/time_posix.c
@@ -120,7 +120,7 @@ void gpr_sleep_until(gpr_timespec until) {
   for (;;) {
     /* We could simplify by using clock_nanosleep instead, but it might be
      * slightly less portable. */
-    now = gpr_now(GPR_CLOCK_REALTIME);
+    now = gpr_now(until.clock_type);
     if (gpr_time_cmp(until, now) <= 0) {
       return;
     }
diff --git a/src/core/support/time_win32.c b/src/core/support/time_win32.c
index 238cd07ebc..7f64c80e27 100644
--- a/src/core/support/time_win32.c
+++ b/src/core/support/time_win32.c
@@ -80,7 +80,7 @@ void gpr_sleep_until(gpr_timespec until) {
   for (;;) {
     /* We could simplify by using clock_nanosleep instead, but it might be
      * slightly less portable. */
-    now = gpr_now(GPR_CLOCK_REALTIME);
+    now = gpr_now(until.clock_type);
     if (gpr_time_cmp(until, now) <= 0) {
       return;
     }
diff --git a/src/core/surface/call.c b/src/core/surface/call.c
index 54f10261e3..0cdb9e22a5 100644
--- a/src/core/surface/call.c
+++ b/src/core/surface/call.c
@@ -352,7 +352,7 @@ grpc_call *grpc_call_create(grpc_channel *channel, grpc_completion_queue *cq,
   }
   grpc_call_stack_init(channel_stack, server_transport_data, initial_op_ptr,
                        CALL_STACK_FROM_CALL(call));
-  if (gpr_time_cmp(send_deadline, gpr_inf_future(GPR_CLOCK_REALTIME)) != 0) {
+  if (gpr_time_cmp(send_deadline, gpr_inf_future(send_deadline.clock_type)) != 0) {
     set_deadline_alarm(call, send_deadline);
   }
   return call;
@@ -1309,8 +1309,8 @@ static void set_deadline_alarm(grpc_call *call, gpr_timespec deadline) {
   }
   GRPC_CALL_INTERNAL_REF(call, "alarm");
   call->have_alarm = 1;
-  grpc_alarm_init(&call->alarm, deadline, call_alarm, call,
-                  gpr_now(GPR_CLOCK_REALTIME));
+  grpc_alarm_init(&call->alarm, gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC), call_alarm, call,
+                  gpr_now(GPR_CLOCK_MONOTONIC));
 }
 
 /* we offset status by a small amount when storing it into transport metadata
diff --git a/src/core/surface/call.h b/src/core/surface/call.h
index 5736e97b59..49fb4de47a 100644
--- a/src/core/surface/call.h
+++ b/src/core/surface/call.h
@@ -134,6 +134,10 @@ void grpc_server_log_request_call(char *file, int line,
                                   grpc_completion_queue *cq_for_notification,
                                   void *tag);
 
+void grpc_server_log_shutdown(char *file, int line, gpr_log_severity severity,
+                              grpc_server *server, grpc_completion_queue *cq,
+                              void *tag);
+
 /* Set a context pointer.
    No thread safety guarantees are made wrt this value. */
 void grpc_call_context_set(grpc_call *call, grpc_context_index elem,
@@ -151,6 +155,9 @@ void *grpc_call_context_get(grpc_call *call, grpc_context_index elem);
   grpc_server_log_request_call(sev, server, call, details, initial_metadata, \
                                cq_bound_to_call, cq_for_notifications, tag)
 
+#define GRPC_SERVER_LOG_SHUTDOWN(sev, server, cq, tag) \
+  if (grpc_trace_batch) grpc_server_log_shutdown(sev, server, cq, tag)
+
 gpr_uint8 grpc_call_is_client(grpc_call *call);
 
 /** Returns a bitset for the encodings (compression algorithms) supported by \a
diff --git a/src/core/surface/call_log_batch.c b/src/core/surface/call_log_batch.c
index 997046d954..7bf8cafc24 100644
--- a/src/core/surface/call_log_batch.c
+++ b/src/core/surface/call_log_batch.c
@@ -136,3 +136,11 @@ void grpc_server_log_request_call(char *file, int line,
           "tag=%p)", server, call, details, initial_metadata,
           cq_bound_to_call, cq_for_notification, tag);
 }
+
+void grpc_server_log_shutdown(char *file, int line, gpr_log_severity severity,
+                              grpc_server *server, grpc_completion_queue *cq,
+                              void *tag) {
+  gpr_log(file, line, severity,
+          "grpc_server_shutdown_and_notify(server=%p, cq=%p, tag=%p)", server,
+          cq, tag);
+}
diff --git a/src/core/surface/completion_queue.c b/src/core/surface/completion_queue.c
index 8484418247..3f60b0b0ba 100644
--- a/src/core/surface/completion_queue.c
+++ b/src/core/surface/completion_queue.c
@@ -148,6 +148,8 @@ grpc_event grpc_completion_queue_next(grpc_completion_queue *cc,
                                       gpr_timespec deadline) {
   grpc_event ret;
 
+  deadline = gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC);
+
   GRPC_CQ_INTERNAL_REF(cc, "next");
   gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset));
   for (;;) {
@@ -188,6 +190,8 @@ grpc_event grpc_completion_queue_pluck(grpc_completion_queue *cc, void *tag,
   grpc_cq_completion *c;
   grpc_cq_completion *prev;
 
+  deadline = gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC);
+
   GRPC_CQ_INTERNAL_REF(cc, "pluck");
   gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset));
   for (;;) {
diff --git a/src/core/surface/server.c b/src/core/surface/server.c
index f2d6b11bc7..439452aea2 100644
--- a/src/core/surface/server.c
+++ b/src/core/surface/server.c
@@ -980,6 +980,8 @@ void grpc_server_shutdown_and_notify(grpc_server *server,
   channel_broadcaster broadcaster;
   request_killer reqkill;
 
+  GRPC_SERVER_LOG_SHUTDOWN(GPR_INFO, server, cq, tag);
+
   /* lock, and gather up some stuff to do */
   gpr_mu_lock(&server->mu_global);
   grpc_cq_begin_op(cq);
diff --git a/src/core/transport/chttp2/parsing.c b/src/core/transport/chttp2/parsing.c
index aa32f2e44a..904b9afce7 100644
--- a/src/core/transport/chttp2/parsing.c
+++ b/src/core/transport/chttp2/parsing.c
@@ -588,7 +588,7 @@ static void on_header(void *tp, grpc_mdelem *md) {
   GPR_ASSERT(stream_parsing);
 
   GRPC_CHTTP2_IF_TRACING(gpr_log(
-      GPR_INFO, "HTTP:%d:HDR: %s: %s", stream_parsing->id,
+      GPR_INFO, "HTTP:%d:HDR:%s: %s: %s", stream_parsing->id,
       transport_parsing->is_client ? "CLI" : "SVR",
       grpc_mdstr_as_c_string(md->key), grpc_mdstr_as_c_string(md->value)));
 
diff --git a/src/core/transport/chttp2/stream_encoder.c b/src/core/transport/chttp2/stream_encoder.c
index d30059abf8..65b31a5afd 100644
--- a/src/core/transport/chttp2/stream_encoder.c
+++ b/src/core/transport/chttp2/stream_encoder.c
@@ -438,7 +438,7 @@ static void deadline_enc(grpc_chttp2_hpack_compressor *c, gpr_timespec deadline,
   char timeout_str[GRPC_CHTTP2_TIMEOUT_ENCODE_MIN_BUFSIZE];
   grpc_mdelem *mdelem;
   grpc_chttp2_encode_timeout(
-      gpr_time_sub(deadline, gpr_now(GPR_CLOCK_REALTIME)), timeout_str);
+      gpr_time_sub(deadline, gpr_now(deadline.clock_type)), timeout_str);
   mdelem = grpc_mdelem_from_metadata_strings(
       c->mdctx, GRPC_MDSTR_REF(c->timeout_key_str),
       grpc_mdstr_from_string(c->mdctx, timeout_str));
@@ -560,6 +560,7 @@ void grpc_chttp2_encode(grpc_stream_op *ops, size_t ops_count, int eof,
   grpc_mdctx *mdctx = compressor->mdctx;
   grpc_linked_mdelem *l;
   int need_unref = 0;
+  gpr_timespec deadline;
 
   GPR_ASSERT(stream_id != 0);
 
@@ -589,9 +590,9 @@ void grpc_chttp2_encode(grpc_stream_op *ops, size_t ops_count, int eof,
           l->md = hpack_enc(compressor, l->md, &st);
           need_unref |= l->md != NULL;
         }
-        if (gpr_time_cmp(op->data.metadata.deadline,
-                         gpr_inf_future(GPR_CLOCK_REALTIME)) != 0) {
-          deadline_enc(compressor, op->data.metadata.deadline, &st);
+        deadline = op->data.metadata.deadline;
+        if (gpr_time_cmp(deadline, gpr_inf_future(deadline.clock_type)) != 0) {
+          deadline_enc(compressor, deadline, &st);
         }
         curop++;
         break;
diff --git a/src/core/transport/transport_op_string.c b/src/core/transport/transport_op_string.c
index 9d127c5472..10d796fc15 100644
--- a/src/core/transport/transport_op_string.c
+++ b/src/core/transport/transport_op_string.c
@@ -61,7 +61,7 @@ static void put_metadata_list(gpr_strvec *b, grpc_metadata_batch md) {
     if (m != md.list.head) gpr_strvec_add(b, gpr_strdup(", "));
     put_metadata(b, m->md);
   }
-  if (gpr_time_cmp(md.deadline, gpr_inf_future(GPR_CLOCK_REALTIME)) != 0) {
+  if (gpr_time_cmp(md.deadline, gpr_inf_future(md.deadline.clock_type)) != 0) {
     char *tmp;
     gpr_asprintf(&tmp, " deadline=%d.%09d", md.deadline.tv_sec,
                  md.deadline.tv_nsec);
diff --git a/src/cpp/client/channel_arguments.cc b/src/cpp/client/channel_arguments.cc
index 92ac5ea6fd..da6602e7af 100644
--- a/src/cpp/client/channel_arguments.cc
+++ b/src/cpp/client/channel_arguments.cc
@@ -33,11 +33,49 @@
 
 #include <grpc++/channel_arguments.h>
 
+#include <grpc/support/log.h>
+
 #include "src/core/channel/channel_args.h"
 
 namespace grpc {
 
-void ChannelArguments::_Experimental_SetCompressionAlgorithm(
+ChannelArguments::ChannelArguments(const ChannelArguments& other)
+    : strings_(other.strings_) {
+  args_.reserve(other.args_.size());
+  auto list_it_dst = strings_.begin();
+  auto list_it_src = other.strings_.begin();
+  for (auto a = other.args_.begin(); a != other.args_.end(); ++a) {
+    grpc_arg ap;
+    ap.type = a->type;
+    GPR_ASSERT(list_it_src->c_str() == a->key);
+    ap.key = const_cast<char*>(list_it_dst->c_str());
+    ++list_it_src;
+    ++list_it_dst;
+    switch (a->type) {
+      case GRPC_ARG_INTEGER:
+        ap.value.integer = a->value.integer;
+        break;
+      case GRPC_ARG_STRING:
+        GPR_ASSERT(list_it_src->c_str() == a->value.string);
+        ap.value.string = const_cast<char*>(list_it_dst->c_str());
+        ++list_it_src;
+        ++list_it_dst;
+        break;
+      case GRPC_ARG_POINTER:
+        ap.value.pointer = a->value.pointer;
+        ap.value.pointer.p = a->value.pointer.copy(ap.value.pointer.p);
+        break;
+    }
+    args_.push_back(ap);
+  }
+}
+
+void ChannelArguments::Swap(ChannelArguments& other) {
+  args_.swap(other.args_);
+  strings_.swap(other.strings_);
+}
+
+void ChannelArguments::SetCompressionAlgorithm(
     grpc_compression_algorithm algorithm) {
   SetInt(GRPC_COMPRESSION_ALGORITHM_ARG, algorithm);
 }
diff --git a/src/cpp/client/client_context.cc b/src/cpp/client/client_context.cc
index 69216d2030..14ab772e50 100644
--- a/src/cpp/client/client_context.cc
+++ b/src/cpp/client/client_context.cc
@@ -79,7 +79,7 @@ void ClientContext::set_call(grpc_call* call,
   }
 }
 
-void ClientContext::_experimental_set_compression_algorithm(
+void ClientContext::set_compression_algorithm(
     grpc_compression_algorithm algorithm) {
   char* algorithm_name = NULL;
   if (!grpc_compression_algorithm_name(algorithm, &algorithm_name)) {
diff --git a/src/cpp/client/create_channel.cc b/src/cpp/client/create_channel.cc
index 510af2bb00..38eeda0dc0 100644
--- a/src/cpp/client/create_channel.cc
+++ b/src/cpp/client/create_channel.cc
@@ -32,9 +32,11 @@
  */
 
 #include <memory>
+#include <sstream>
 
 #include "src/cpp/client/channel.h"
 #include <grpc++/channel_interface.h>
+#include <grpc++/channel_arguments.h>
 #include <grpc++/create_channel.h>
 
 namespace grpc {
@@ -43,7 +45,12 @@ class ChannelArguments;
 std::shared_ptr<ChannelInterface> CreateChannel(
     const grpc::string& target, const std::shared_ptr<Credentials>& creds,
     const ChannelArguments& args) {
-  return creds ? creds->CreateChannel(target, args)
+  ChannelArguments cp_args = args;
+  std::ostringstream user_agent_prefix;
+  user_agent_prefix << "grpc-c++/" << grpc_version_string();
+  cp_args.SetString(GRPC_ARG_PRIMARY_USER_AGENT_STRING,
+                    user_agent_prefix.str());
+  return creds ? creds->CreateChannel(target, cp_args)
                : std::shared_ptr<ChannelInterface>(
                      new Channel(target, grpc_lame_client_channel_create()));
 }
diff --git a/src/csharp/Grpc.Auth/GoogleCredential.cs b/src/csharp/Grpc.Auth/GoogleCredential.cs
index 8d5e543a21..7edf19ed67 100644
--- a/src/csharp/Grpc.Auth/GoogleCredential.cs
+++ b/src/csharp/Grpc.Auth/GoogleCredential.cs
@@ -35,8 +35,11 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Security.Cryptography;
+using System.Threading;
+using System.Threading.Tasks;
 
 using Google.Apis.Auth.OAuth2;
+using Google.Apis.Auth.OAuth2.Responses;
 using Newtonsoft.Json.Linq;
 using Org.BouncyCastle.Crypto.Parameters;
 using Org.BouncyCastle.Security;
@@ -100,6 +103,19 @@ namespace Grpc.Auth
             return new GoogleCredential(serviceCredential);
         }
 
+        public Task<bool> RequestAccessTokenAsync(CancellationToken taskCancellationToken)
+        {
+            return credential.RequestAccessTokenAsync(taskCancellationToken);
+        }
+
+        public TokenResponse Token
+        {
+            get
+            {
+                return credential.Token;
+            }
+        }
+
         internal ServiceCredential InternalCredential
         {
             get
diff --git a/src/csharp/Grpc.Core.Tests/ClientServerTest.cs b/src/csharp/Grpc.Core.Tests/ClientServerTest.cs
index e797dd82f2..8ba2c8a9a2 100644
--- a/src/csharp/Grpc.Core.Tests/ClientServerTest.cs
+++ b/src/csharp/Grpc.Core.Tests/ClientServerTest.cs
@@ -33,6 +33,7 @@
 
 using System;
 using System.Diagnostics;
+using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using Grpc.Core;
@@ -99,17 +100,17 @@ namespace Grpc.Core.Tests
         [Test]
         public void UnaryCall()
         {
-            var call = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
-            Assert.AreEqual("ABC", Calls.BlockingUnaryCall(call, "ABC", CancellationToken.None));
+            var internalCall = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
+            Assert.AreEqual("ABC", Calls.BlockingUnaryCall(internalCall, "ABC", CancellationToken.None));
         }
 
         [Test]
         public void UnaryCall_ServerHandlerThrows()
         {
-            var call = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
+            var internalCall = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
             try
             {
-                Calls.BlockingUnaryCall(call, "THROW", CancellationToken.None);
+                Calls.BlockingUnaryCall(internalCall, "THROW", CancellationToken.None);
                 Assert.Fail();
             }
             catch (RpcException e)
@@ -119,10 +120,40 @@ namespace Grpc.Core.Tests
         }
 
         [Test]
+        public void UnaryCall_ServerHandlerThrowsRpcException()
+        {
+            var internalCall = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
+            try
+            {
+                Calls.BlockingUnaryCall(internalCall, "THROW_UNAUTHENTICATED", CancellationToken.None);
+                Assert.Fail();
+            }
+            catch (RpcException e)
+            {
+                Assert.AreEqual(StatusCode.Unauthenticated, e.Status.StatusCode);
+            }
+        }
+
+        [Test]
+        public void UnaryCall_ServerHandlerSetsStatus()
+        {
+            var internalCall = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
+            try
+            {
+                Calls.BlockingUnaryCall(internalCall, "SET_UNAUTHENTICATED", CancellationToken.None);
+                Assert.Fail();
+            }
+            catch (RpcException e)
+            {
+                Assert.AreEqual(StatusCode.Unauthenticated, e.Status.StatusCode); 
+            }
+        }
+
+        [Test]
         public void AsyncUnaryCall()
         {
-            var call = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
-            var result = Calls.AsyncUnaryCall(call, "ABC", CancellationToken.None).Result;
+            var internalCall = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
+            var result = Calls.AsyncUnaryCall(internalCall, "ABC", CancellationToken.None).ResponseAsync.Result;
             Assert.AreEqual("ABC", result);
         }
 
@@ -131,10 +162,10 @@ namespace Grpc.Core.Tests
         {
             Task.Run(async () =>
             {
-                var call = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
+                var internalCall = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
                 try
                 {
-                    await Calls.AsyncUnaryCall(call, "THROW", CancellationToken.None);
+                    await Calls.AsyncUnaryCall(internalCall, "THROW", CancellationToken.None);
                     Assert.Fail();
                 }
                 catch (RpcException e)
@@ -149,11 +180,11 @@ namespace Grpc.Core.Tests
         {
             Task.Run(async () => 
             {
-                var call = new Call<string, string>(ServiceName, ConcatAndEchoMethod, channel, Metadata.Empty);
-                var callResult = Calls.AsyncClientStreamingCall(call, CancellationToken.None);
+                var internalCall = new Call<string, string>(ServiceName, ConcatAndEchoMethod, channel, Metadata.Empty);
+                var call = Calls.AsyncClientStreamingCall(internalCall, CancellationToken.None);
 
-                await callResult.RequestStream.WriteAll(new string[] { "A", "B", "C" });
-                Assert.AreEqual("ABC", await callResult.Result);
+                await call.RequestStream.WriteAll(new string[] { "A", "B", "C" });
+                Assert.AreEqual("ABC", await call.ResponseAsync);
             }).Wait();
         }
 
@@ -162,10 +193,10 @@ namespace Grpc.Core.Tests
         {
             Task.Run(async () => 
             {
-                var call = new Call<string, string>(ServiceName, ConcatAndEchoMethod, channel, Metadata.Empty);
+                var internalCall = new Call<string, string>(ServiceName, ConcatAndEchoMethod, channel, Metadata.Empty);
 
                 var cts = new CancellationTokenSource();
-                var callResult = Calls.AsyncClientStreamingCall(call, cts.Token);
+                var call = Calls.AsyncClientStreamingCall(internalCall, cts.Token);
 
                 // TODO(jtattermusch): we need this to ensure call has been initiated once we cancel it.
                 await Task.Delay(1000);
@@ -173,7 +204,7 @@ namespace Grpc.Core.Tests
 
                 try
                 {
-                    await callResult.Result;
+                    await call.ResponseAsync;
                 }
                 catch (RpcException e)
                 {
@@ -183,29 +214,53 @@ namespace Grpc.Core.Tests
         }
 
         [Test]
+        public void AsyncUnaryCall_EchoMetadata()
+        {
+            var headers = new Metadata
+            {
+                new Metadata.Entry("asciiHeader", "abcdefg"),
+                new Metadata.Entry("binaryHeader-bin", new byte[] { 1, 2, 3, 0, 0xff }),
+            };
+            var internalCall = new Call<string, string>(ServiceName, EchoMethod, channel, headers);
+            var call = Calls.AsyncUnaryCall(internalCall, "ABC", CancellationToken.None);
+
+            Assert.AreEqual("ABC", call.ResponseAsync.Result);
+
+            Assert.AreEqual(StatusCode.OK, call.GetStatus().StatusCode);
+
+            var trailers = call.GetTrailers();
+            Assert.AreEqual(2, trailers.Count);
+            Assert.AreEqual(headers[0].Key, trailers[0].Key);
+            Assert.AreEqual(headers[0].Value, trailers[0].Value);
+
+            Assert.AreEqual(headers[1].Key, trailers[1].Key);
+            CollectionAssert.AreEqual(headers[1].ValueBytes, trailers[1].ValueBytes);
+        }
+
+        [Test]
         public void UnaryCall_DisposedChannel()
         {
             channel.Dispose();
 
-            var call = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
-            Assert.Throws(typeof(ObjectDisposedException), () => Calls.BlockingUnaryCall(call, "ABC", CancellationToken.None));
+            var internalCall = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
+            Assert.Throws(typeof(ObjectDisposedException), () => Calls.BlockingUnaryCall(internalCall, "ABC", CancellationToken.None));
         }
 
         [Test]
         public void UnaryCallPerformance()
         {
-            var call = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
+            var internalCall = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
             BenchmarkUtil.RunBenchmark(100, 100,
-                                       () => { Calls.BlockingUnaryCall(call, "ABC", default(CancellationToken)); });
+                                       () => { Calls.BlockingUnaryCall(internalCall, "ABC", default(CancellationToken)); });
         }
             
         [Test]
         public void UnknownMethodHandler()
         {
-            var call = new Call<string, string>(ServiceName, NonexistentMethod, channel, Metadata.Empty);
+            var internalCall = new Call<string, string>(ServiceName, NonexistentMethod, channel, Metadata.Empty);
             try
             {
-                Calls.BlockingUnaryCall(call, "ABC", default(CancellationToken));
+                Calls.BlockingUnaryCall(internalCall, "ABC", default(CancellationToken));
                 Assert.Fail();
             }
             catch (RpcException e)
@@ -214,16 +269,48 @@ namespace Grpc.Core.Tests
             }
         }
 
-        private static async Task<string> EchoHandler(ServerCallContext context, string request)
+        [Test]
+        public void UserAgentStringPresent()
         {
+            var internalCall = new Call<string, string>(ServiceName, EchoMethod, channel, Metadata.Empty);
+            string userAgent = Calls.BlockingUnaryCall(internalCall, "RETURN-USER-AGENT", CancellationToken.None);
+            Assert.IsTrue(userAgent.StartsWith("grpc-csharp/"));
+        }
+
+        private static async Task<string> EchoHandler(string request, ServerCallContext context)
+        {
+            foreach (Metadata.Entry metadataEntry in context.RequestHeaders)
+            {
+                if (metadataEntry.Key != "user-agent")
+                {
+                    context.ResponseTrailers.Add(metadataEntry);
+                }
+            }
+
+            if (request == "RETURN-USER-AGENT")
+            {
+                return context.RequestHeaders.Where(entry => entry.Key == "user-agent").Single().Value;
+            }
+
             if (request == "THROW")
             {
                 throw new Exception("This was thrown on purpose by a test");
             }
+
+            if (request == "THROW_UNAUTHENTICATED")
+            {
+                throw new RpcException(new Status(StatusCode.Unauthenticated, ""));
+            }
+
+            if (request == "SET_UNAUTHENTICATED")
+            {
+                context.Status = new Status(StatusCode.Unauthenticated, "");
+            }
+
             return request;
         }
 
-        private static async Task<string> ConcatAndEchoHandler(ServerCallContext context, IAsyncStreamReader<string> requestStream)
+        private static async Task<string> ConcatAndEchoHandler(IAsyncStreamReader<string> requestStream, ServerCallContext context)
         {
             string result = "";
             await requestStream.ForEach(async (request) =>
diff --git a/src/csharp/Grpc.Core.Tests/Internal/MetadataArraySafeHandleTest.cs b/src/csharp/Grpc.Core.Tests/Internal/MetadataArraySafeHandleTest.cs
index 320423b245..46469113c5 100644
--- a/src/csharp/Grpc.Core.Tests/Internal/MetadataArraySafeHandleTest.cs
+++ b/src/csharp/Grpc.Core.Tests/Internal/MetadataArraySafeHandleTest.cs
@@ -51,12 +51,34 @@ namespace Grpc.Core.Internal.Tests
         [Test]
         public void CreateAndDestroy()
         {
-            var metadata = new Metadata {
+            var metadata = new Metadata
+            {
                 new Metadata.Entry("host", "somehost"),
                 new Metadata.Entry("header2", "header value"),
             };
             var nativeMetadata = MetadataArraySafeHandle.Create(metadata);
             nativeMetadata.Dispose();
         }
+
+        [Test]
+        public void ReadMetadataFromPtrUnsafe()
+        {
+            var metadata = new Metadata
+            {
+                new Metadata.Entry("host", "somehost"),
+                new Metadata.Entry("header2", "header value"),
+            };
+            var nativeMetadata = MetadataArraySafeHandle.Create(metadata);
+
+            var copy = MetadataArraySafeHandle.ReadMetadataFromPtrUnsafe(nativeMetadata.Handle);
+            Assert.AreEqual(2, copy.Count);
+
+            Assert.AreEqual("host", copy[0].Key);
+            Assert.AreEqual("somehost", copy[0].Value);
+            Assert.AreEqual("header2", copy[1].Key);
+            Assert.AreEqual("header value", copy[1].Value);
+
+            nativeMetadata.Dispose();
+        }
     }
 }
diff --git a/src/csharp/Grpc.Core.Tests/TimespecTest.cs b/src/csharp/Grpc.Core.Tests/TimespecTest.cs
index 5831121add..a34b407a01 100644
--- a/src/csharp/Grpc.Core.Tests/TimespecTest.cs
+++ b/src/csharp/Grpc.Core.Tests/TimespecTest.cs
@@ -59,6 +59,19 @@ namespace Grpc.Core.Internal.Tests
         }
 
         [Test]
+        public void ToDateTime()
+        {
+            Assert.AreEqual(new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc),
+                new Timespec(IntPtr.Zero, 0).ToDateTime());
+
+            Assert.AreEqual(new DateTime(1970, 1, 1, 0, 0, 10, DateTimeKind.Utc).AddTicks(50),
+                new Timespec(new IntPtr(10), 5000).ToDateTime());
+
+            Assert.AreEqual(new DateTime(2015, 7, 21, 4, 21, 48, DateTimeKind.Utc),
+                new Timespec(new IntPtr(1437452508), 0).ToDateTime());
+        }
+
+        [Test]
         public void Add()
         {
             var t = new Timespec { tv_sec = new IntPtr(12345), tv_nsec = 123456789 };
diff --git a/src/csharp/Grpc.Core/AsyncClientStreamingCall.cs b/src/csharp/Grpc.Core/AsyncClientStreamingCall.cs
index d66b0d4974..bf020cd627 100644
--- a/src/csharp/Grpc.Core/AsyncClientStreamingCall.cs
+++ b/src/csharp/Grpc.Core/AsyncClientStreamingCall.cs
@@ -43,24 +43,28 @@ namespace Grpc.Core
     public sealed class AsyncClientStreamingCall<TRequest, TResponse> : IDisposable
     {
         readonly IClientStreamWriter<TRequest> requestStream;
-        readonly Task<TResponse> result;
+        readonly Task<TResponse> responseAsync;
+        readonly Func<Status> getStatusFunc;
+        readonly Func<Metadata> getTrailersFunc;
         readonly Action disposeAction;
 
-        public AsyncClientStreamingCall(IClientStreamWriter<TRequest> requestStream, Task<TResponse> result, Action disposeAction)
+        public AsyncClientStreamingCall(IClientStreamWriter<TRequest> requestStream, Task<TResponse> responseAsync, Func<Status> getStatusFunc, Func<Metadata> getTrailersFunc, Action disposeAction)
         {
             this.requestStream = requestStream;
-            this.result = result;
+            this.responseAsync = responseAsync;
+            this.getStatusFunc = getStatusFunc;
+            this.getTrailersFunc = getTrailersFunc;
             this.disposeAction = disposeAction;
         }
 
         /// <summary>
         /// Asynchronous call result.
         /// </summary>
-        public Task<TResponse> Result
+        public Task<TResponse> ResponseAsync
         {
             get
             {
-                return this.result;
+                return this.responseAsync;
             }
         }
 
@@ -81,11 +85,11 @@ namespace Grpc.Core
         /// <returns></returns>
         public TaskAwaiter<TResponse> GetAwaiter()
         {
-            return result.GetAwaiter();
+            return responseAsync.GetAwaiter();
         }
 
         /// <summary>
-        /// Provides means to provide after the call.
+        /// Provides means to cleanup after the call.
         /// If the call has already finished normally (request stream has been completed and call result has been received), doesn't do anything.
         /// Otherwise, requests cancellation of the call which should terminate all pending async operations associated with the call.
         /// As a result, all resources being used by the call should be released eventually.
diff --git a/src/csharp/Grpc.Core/AsyncDuplexStreamingCall.cs b/src/csharp/Grpc.Core/AsyncDuplexStreamingCall.cs
index 4c0d5936ac..0979de606f 100644
--- a/src/csharp/Grpc.Core/AsyncDuplexStreamingCall.cs
+++ b/src/csharp/Grpc.Core/AsyncDuplexStreamingCall.cs
@@ -44,12 +44,16 @@ namespace Grpc.Core
     {
         readonly IClientStreamWriter<TRequest> requestStream;
         readonly IAsyncStreamReader<TResponse> responseStream;
+        readonly Func<Status> getStatusFunc;
+        readonly Func<Metadata> getTrailersFunc;
         readonly Action disposeAction;
 
-        public AsyncDuplexStreamingCall(IClientStreamWriter<TRequest> requestStream, IAsyncStreamReader<TResponse> responseStream, Action disposeAction)
+        public AsyncDuplexStreamingCall(IClientStreamWriter<TRequest> requestStream, IAsyncStreamReader<TResponse> responseStream, Func<Status> getStatusFunc, Func<Metadata> getTrailersFunc, Action disposeAction)
         {
             this.requestStream = requestStream;
             this.responseStream = responseStream;
+            this.getStatusFunc = getStatusFunc;
+            this.getTrailersFunc = getTrailersFunc;
             this.disposeAction = disposeAction;
         }
 
@@ -76,6 +80,24 @@ namespace Grpc.Core
         }
 
         /// <summary>
+        /// Gets the call status if the call has already finished.
+        /// Throws InvalidOperationException otherwise.
+        /// </summary>
+        public Status GetStatus()
+        {
+            return getStatusFunc();
+        }
+
+        /// <summary>
+        /// Gets the call trailing metadata if the call has already finished.
+        /// Throws InvalidOperationException otherwise.
+        /// </summary>
+        public Metadata GetTrailers()
+        {
+            return getTrailersFunc();
+        }
+
+        /// <summary>
         /// Provides means to cleanup after the call.
         /// If the call has already finished normally (request stream has been completed and response stream has been fully read), doesn't do anything.
         /// Otherwise, requests cancellation of the call which should terminate all pending async operations associated with the call.
diff --git a/src/csharp/Grpc.Core/AsyncServerStreamingCall.cs b/src/csharp/Grpc.Core/AsyncServerStreamingCall.cs
index 7a479b9a23..380efcdb0e 100644
--- a/src/csharp/Grpc.Core/AsyncServerStreamingCall.cs
+++ b/src/csharp/Grpc.Core/AsyncServerStreamingCall.cs
@@ -43,11 +43,15 @@ namespace Grpc.Core
     public sealed class AsyncServerStreamingCall<TResponse> : IDisposable
     {
         readonly IAsyncStreamReader<TResponse> responseStream;
+        readonly Func<Status> getStatusFunc;
+        readonly Func<Metadata> getTrailersFunc;
         readonly Action disposeAction;
 
-        public AsyncServerStreamingCall(IAsyncStreamReader<TResponse> responseStream, Action disposeAction)
+        public AsyncServerStreamingCall(IAsyncStreamReader<TResponse> responseStream, Func<Status> getStatusFunc, Func<Metadata> getTrailersFunc, Action disposeAction)
         {
             this.responseStream = responseStream;
+            this.getStatusFunc = getStatusFunc;
+            this.getTrailersFunc = getTrailersFunc;
             this.disposeAction = disposeAction;
         }
 
@@ -63,6 +67,24 @@ namespace Grpc.Core
         }
 
         /// <summary>
+        /// Gets the call status if the call has already finished.
+        /// Throws InvalidOperationException otherwise.
+        /// </summary>
+        public Status GetStatus()
+        {
+            return getStatusFunc();
+        }
+
+        /// <summary>
+        /// Gets the call trailing metadata if the call has already finished.
+        /// Throws InvalidOperationException otherwise.
+        /// </summary>
+        public Metadata GetTrailers()
+        {
+            return getTrailersFunc();
+        }
+
+        /// <summary>
         /// Provides means to cleanup after the call.
         /// If the call has already finished normally (response stream has been fully read), doesn't do anything.
         /// Otherwise, requests cancellation of the call which should terminate all pending async operations associated with the call.
diff --git a/src/csharp/Grpc.Core/AsyncUnaryCall.cs b/src/csharp/Grpc.Core/AsyncUnaryCall.cs
new file mode 100644
index 0000000000..224e343916
--- /dev/null
+++ b/src/csharp/Grpc.Core/AsyncUnaryCall.cs
@@ -0,0 +1,106 @@
+#region Copyright notice and license
+
+// 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.
+
+#endregion
+
+using System;
+using System.Runtime.CompilerServices;
+using System.Threading.Tasks;
+
+namespace Grpc.Core
+{
+    /// <summary>
+    /// Return type for single request - single response call.
+    /// </summary>
+    public sealed class AsyncUnaryCall<TResponse> : IDisposable
+    {
+        readonly Task<TResponse> responseAsync;
+        readonly Func<Status> getStatusFunc;
+        readonly Func<Metadata> getTrailersFunc;
+        readonly Action disposeAction;
+
+        public AsyncUnaryCall(Task<TResponse> responseAsync, Func<Status> getStatusFunc, Func<Metadata> getTrailersFunc, Action disposeAction)
+        {
+            this.responseAsync = responseAsync;
+            this.getStatusFunc = getStatusFunc;
+            this.getTrailersFunc = getTrailersFunc;
+            this.disposeAction = disposeAction;
+        }
+
+        /// <summary>
+        /// Asynchronous call result.
+        /// </summary>
+        public Task<TResponse> ResponseAsync
+        {
+            get
+            {
+                return this.responseAsync;
+            }
+        }
+
+        /// <summary>
+        /// Allows awaiting this object directly.
+        /// </summary>
+        public TaskAwaiter<TResponse> GetAwaiter()
+        {
+            return responseAsync.GetAwaiter();
+        }
+
+        /// <summary>
+        /// Gets the call status if the call has already finished.
+        /// Throws InvalidOperationException otherwise.
+        /// </summary>
+        public Status GetStatus()
+        {
+            return getStatusFunc();
+        }
+
+        /// <summary>
+        /// Gets the call trailing metadata if the call has already finished.
+        /// Throws InvalidOperationException otherwise.
+        /// </summary>
+        public Metadata GetTrailers()
+        {
+            return getTrailersFunc();
+        }
+
+        /// <summary>
+        /// Provides means to cleanup after the call.
+        /// If the call has already finished normally (request stream has been completed and call result has been received), doesn't do anything.
+        /// Otherwise, requests cancellation of the call which should terminate all pending async operations associated with the call.
+        /// As a result, all resources being used by the call should be released eventually.
+        /// </summary>
+        public void Dispose()
+        {
+            disposeAction.Invoke();
+        }
+    }
+}
diff --git a/src/csharp/Grpc.Core/Calls.cs b/src/csharp/Grpc.Core/Calls.cs
index 9e95182c72..359fe53741 100644
--- a/src/csharp/Grpc.Core/Calls.cs
+++ b/src/csharp/Grpc.Core/Calls.cs
@@ -53,7 +53,7 @@ namespace Grpc.Core
             return asyncCall.UnaryCall(call.Channel, call.Name, req, call.Headers);
         }
 
-        public static async Task<TResponse> AsyncUnaryCall<TRequest, TResponse>(Call<TRequest, TResponse> call, TRequest req, CancellationToken token)
+        public static AsyncUnaryCall<TResponse> AsyncUnaryCall<TRequest, TResponse>(Call<TRequest, TResponse> call, TRequest req, CancellationToken token)
             where TRequest : class
             where TResponse : class
         {
@@ -61,7 +61,7 @@ namespace Grpc.Core
             asyncCall.Initialize(call.Channel, call.Channel.CompletionQueue, call.Name);
             var asyncResult = asyncCall.UnaryCallAsync(req, call.Headers);
             RegisterCancellationCallback(asyncCall, token);
-            return await asyncResult;
+            return new AsyncUnaryCall<TResponse>(asyncResult, asyncCall.GetStatus, asyncCall.GetTrailers, asyncCall.Cancel);
         }
 
         public static AsyncServerStreamingCall<TResponse> AsyncServerStreamingCall<TRequest, TResponse>(Call<TRequest, TResponse> call, TRequest req, CancellationToken token)
@@ -73,7 +73,7 @@ namespace Grpc.Core
             asyncCall.StartServerStreamingCall(req, call.Headers);
             RegisterCancellationCallback(asyncCall, token);
             var responseStream = new ClientResponseStream<TRequest, TResponse>(asyncCall);
-            return new AsyncServerStreamingCall<TResponse>(responseStream, asyncCall.Cancel);
+            return new AsyncServerStreamingCall<TResponse>(responseStream, asyncCall.GetStatus, asyncCall.GetTrailers, asyncCall.Cancel);
         }
 
         public static AsyncClientStreamingCall<TRequest, TResponse> AsyncClientStreamingCall<TRequest, TResponse>(Call<TRequest, TResponse> call, CancellationToken token)
@@ -85,7 +85,7 @@ namespace Grpc.Core
             var resultTask = asyncCall.ClientStreamingCallAsync(call.Headers);
             RegisterCancellationCallback(asyncCall, token);
             var requestStream = new ClientRequestStream<TRequest, TResponse>(asyncCall);
-            return new AsyncClientStreamingCall<TRequest, TResponse>(requestStream, resultTask, asyncCall.Cancel);
+            return new AsyncClientStreamingCall<TRequest, TResponse>(requestStream, resultTask, asyncCall.GetStatus, asyncCall.GetTrailers, asyncCall.Cancel);
         }
 
         public static AsyncDuplexStreamingCall<TRequest, TResponse> AsyncDuplexStreamingCall<TRequest, TResponse>(Call<TRequest, TResponse> call, CancellationToken token)
@@ -98,7 +98,7 @@ namespace Grpc.Core
             RegisterCancellationCallback(asyncCall, token);
             var requestStream = new ClientRequestStream<TRequest, TResponse>(asyncCall);
             var responseStream = new ClientResponseStream<TRequest, TResponse>(asyncCall);
-            return new AsyncDuplexStreamingCall<TRequest, TResponse>(requestStream, responseStream, asyncCall.Cancel);
+            return new AsyncDuplexStreamingCall<TRequest, TResponse>(requestStream, responseStream, asyncCall.GetStatus, asyncCall.GetTrailers, asyncCall.Cancel);
         }
 
         private static void RegisterCancellationCallback<TRequest, TResponse>(AsyncCall<TRequest, TResponse> asyncCall, CancellationToken token)
diff --git a/src/csharp/Grpc.Core/Channel.cs b/src/csharp/Grpc.Core/Channel.cs
index 5baf260003..e5c6abd2cb 100644
--- a/src/csharp/Grpc.Core/Channel.cs
+++ b/src/csharp/Grpc.Core/Channel.cs
@@ -28,11 +28,14 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #endregion
+
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using System.Runtime.InteropServices;
 using System.Threading;
 using System.Threading.Tasks;
+
 using Grpc.Core.Internal;
 
 namespace Grpc.Core
@@ -44,6 +47,7 @@ namespace Grpc.Core
     {
         readonly GrpcEnvironment environment;
         readonly ChannelSafeHandle handle;
+        readonly List<ChannelOption> options;
         readonly string target;
         bool disposed;
 
@@ -57,7 +61,10 @@ namespace Grpc.Core
         public Channel(string host, Credentials credentials = null, IEnumerable<ChannelOption> options = null)
         {
             this.environment = GrpcEnvironment.GetInstance();
-            using (ChannelArgsSafeHandle nativeChannelArgs = ChannelOptions.CreateChannelArgs(options))
+            this.options = options != null ? new List<ChannelOption>(options) : new List<ChannelOption>();
+
+            EnsureUserAgentChannelOption(this.options);
+            using (ChannelArgsSafeHandle nativeChannelArgs = ChannelOptions.CreateChannelArgs(this.options))
             {
                 if (credentials != null)
                 {
@@ -71,7 +78,7 @@ namespace Grpc.Core
                     this.handle = ChannelSafeHandle.Create(host, nativeChannelArgs);
                 }
             }
-            this.target = GetOverridenTarget(host, options);
+            this.target = GetOverridenTarget(host, this.options);
         }
 
         /// <summary>
@@ -141,6 +148,20 @@ namespace Grpc.Core
             }
         }
 
+        private static void EnsureUserAgentChannelOption(List<ChannelOption> options)
+        {
+            if (!options.Any((option) => option.Name == ChannelOptions.PrimaryUserAgentString))
+            {
+                options.Add(new ChannelOption(ChannelOptions.PrimaryUserAgentString, GetUserAgentString()));
+            }
+        }
+
+        private static string GetUserAgentString()
+        {
+            // TODO(jtattermusch): it would be useful to also provide .NET/mono version.
+            return string.Format("grpc-csharp/{0}", VersionInfo.CurrentVersion);
+        }
+
         /// <summary>
         /// Look for SslTargetNameOverride option and return its value instead of originalTarget
         /// if found.
diff --git a/src/csharp/Grpc.Core/ChannelOptions.cs b/src/csharp/Grpc.Core/ChannelOptions.cs
index bc23bb59b1..9fe03d2805 100644
--- a/src/csharp/Grpc.Core/ChannelOptions.cs
+++ b/src/csharp/Grpc.Core/ChannelOptions.cs
@@ -115,41 +115,49 @@ namespace Grpc.Core
         }
     }
 
+    /// <summary>
+    /// Defines names of supported channel options.
+    /// </summary>
     public static class ChannelOptions
     {
-        // Override SSL target check. Only to be used for testing.
+        /// <summary>Override SSL target check. Only to be used for testing.</summary>
         public const string SslTargetNameOverride = "grpc.ssl_target_name_override";
 
-        // Enable census for tracing and stats collection
+        /// <summary>Enable census for tracing and stats collection</summary>
         public const string Census = "grpc.census";
 
-        // Maximum number of concurrent incoming streams to allow on a http2 connection
+        /// <summary>Maximum number of concurrent incoming streams to allow on a http2 connection</summary>
         public const string MaxConcurrentStreams = "grpc.max_concurrent_streams";
 
-        // Maximum message length that the channel can receive
+        /// <summary>Maximum message length that the channel can receive</summary>
         public const string MaxMessageLength = "grpc.max_message_length";
 
-        // Initial sequence number for http2 transports
+        /// <summary>Initial sequence number for http2 transports</summary>
         public const string Http2InitialSequenceNumber = "grpc.http2.initial_sequence_number";
 
+        /// <summary>Primary user agent: goes at the start of the user-agent metadata</summary>
+        public const string PrimaryUserAgentString = "grpc.primary_user_agent";
+
+        /// <summary> Secondary user agent: goes at the end of the user-agent metadata</summary>
+        public const string SecondaryUserAgentString = "grpc.secondary_user_agent";
+
         /// <summary>
         /// Creates native object for a collection of channel options.
         /// </summary>
         /// <returns>The native channel arguments.</returns>
-        internal static ChannelArgsSafeHandle CreateChannelArgs(IEnumerable<ChannelOption> options)
+        internal static ChannelArgsSafeHandle CreateChannelArgs(List<ChannelOption> options)
         {
-            if (options == null)
+            if (options == null || options.Count == 0)
             {
                 return ChannelArgsSafeHandle.CreateNull();
             }
-            var optionList = new List<ChannelOption>(options);  // It's better to do defensive copy
             ChannelArgsSafeHandle nativeArgs = null;
             try
             {
-                nativeArgs = ChannelArgsSafeHandle.Create(optionList.Count);
-                for (int i = 0; i < optionList.Count; i++)
+                nativeArgs = ChannelArgsSafeHandle.Create(options.Count);
+                for (int i = 0; i < options.Count; i++)
                 {
-                    var option = optionList[i];
+                    var option = options[i];
                     if (option.Type == ChannelOption.OptionType.Integer)
                     {
                         nativeArgs.SetInteger(i, option.Name, option.IntValue);
diff --git a/src/csharp/Grpc.Core/Grpc.Core.csproj b/src/csharp/Grpc.Core/Grpc.Core.csproj
index a227fe5477..fd68b91851 100644
--- a/src/csharp/Grpc.Core/Grpc.Core.csproj
+++ b/src/csharp/Grpc.Core/Grpc.Core.csproj
@@ -33,13 +33,12 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="System" />
-    <Reference Include="System.Collections.Immutable, Version=1.1.36.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
-      <HintPath>..\packages\System.Collections.Immutable.1.1.36\lib\portable-net45+win8+wp8+wpa81\System.Collections.Immutable.dll</HintPath>
-    </Reference>
     <Reference Include="System.Interactive.Async">
       <HintPath>..\packages\Ix-Async.1.2.3\lib\net45\System.Interactive.Async.dll</HintPath>
     </Reference>
+    <Reference Include="System.Collections.Immutable">
+      <HintPath>..\packages\System.Collections.Immutable.1.1.36\lib\portable-net45+win8+wp8+wpa81\System.Collections.Immutable.dll</HintPath>
+    </Reference>
   </ItemGroup>
   <ItemGroup>
     <Compile Include="AsyncDuplexStreamingCall.cs" />
@@ -102,6 +101,8 @@
     <Compile Include="Internal\CompletionRegistry.cs" />
     <Compile Include="Internal\BatchContextSafeHandle.cs" />
     <Compile Include="ChannelOptions.cs" />
+    <Compile Include="AsyncUnaryCall.cs" />
+    <Compile Include="VersionInfo.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="Grpc.Core.nuspec" />
diff --git a/src/csharp/Grpc.Core/Internal/AsyncCall.cs b/src/csharp/Grpc.Core/Internal/AsyncCall.cs
index 24b75d1668..f983dbb759 100644
--- a/src/csharp/Grpc.Core/Internal/AsyncCall.cs
+++ b/src/csharp/Grpc.Core/Internal/AsyncCall.cs
@@ -52,8 +52,8 @@ namespace Grpc.Core.Internal
         // Completion of a pending unary response if not null.
         TaskCompletionSource<TResponse> unaryResponseTcs;
 
-        // Set after status is received. Only used for streaming response calls.
-        Status? finishedStatus;
+        // Set after status is received. Used for both unary and streaming response calls.
+        ClientSideStatus? finishedStatus;
 
         bool readObserverCompleted;  // True if readObserver has already been completed.
 
@@ -249,6 +249,32 @@ namespace Grpc.Core.Internal
         }
 
         /// <summary>
+        /// Gets the resulting status if the call has already finished.
+        /// Throws InvalidOperationException otherwise.
+        /// </summary>
+        public Status GetStatus()
+        {
+            lock (myLock)
+            {
+                Preconditions.CheckState(finishedStatus.HasValue, "Status can only be accessed once the call has finished.");
+                return finishedStatus.Value.Status;
+            }
+        }
+
+        /// <summary>
+        /// Gets the trailing metadata if the call has already finished.
+        /// Throws InvalidOperationException otherwise.
+        /// </summary>
+        public Metadata GetTrailers()
+        {
+            lock (myLock)
+            {
+                Preconditions.CheckState(finishedStatus.HasValue, "Trailers can only be accessed once the call has finished.");
+                return finishedStatus.Value.Trailers;
+            }
+        }
+
+        /// <summary>
         /// On client-side, we only fire readCompletionDelegate once all messages have been read 
         /// and status has been received.
         /// </summary>
@@ -265,7 +291,7 @@ namespace Grpc.Core.Internal
 
                 if (shouldComplete)
                 {
-                    var status = finishedStatus.Value;
+                    var status = finishedStatus.Value.Status;
                     if (status.StatusCode != StatusCode.OK)
                     {
                         FireCompletion(completionDelegate, default(TResponse), new RpcException(status));
@@ -288,9 +314,13 @@ namespace Grpc.Core.Internal
         /// </summary>
         private void HandleUnaryResponse(bool success, BatchContextSafeHandle ctx)
         {
+            var fullStatus = ctx.GetReceivedStatusOnClient();
+
             lock (myLock)
             {
                 finished = true;
+                finishedStatus = fullStatus;
+
                 halfclosed = true;
 
                 ReleaseResourcesIfPossible();
@@ -302,7 +332,8 @@ namespace Grpc.Core.Internal
                 return;
             }
 
-            var status = ctx.GetReceivedStatus();
+            var status = fullStatus.Status;
+
             if (status.StatusCode != StatusCode.OK)
             {
                 unaryResponseTcs.SetException(new RpcException(status));
@@ -321,13 +352,13 @@ namespace Grpc.Core.Internal
         /// </summary>
         private void HandleFinished(bool success, BatchContextSafeHandle ctx)
         {
-            var status = ctx.GetReceivedStatus();
+            var fullStatus = ctx.GetReceivedStatusOnClient();
 
             AsyncCompletionDelegate<TResponse> origReadCompletionDelegate = null;
             lock (myLock)
             {
                 finished = true;
-                finishedStatus = status;
+                finishedStatus = fullStatus;
 
                 origReadCompletionDelegate = readCompletionDelegate;
 
diff --git a/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs b/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
index 309067ea9d..f809f4a84c 100644
--- a/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
+++ b/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
@@ -101,14 +101,17 @@ namespace Grpc.Core.Internal
         /// Only one pending send action is allowed at any given time.
         /// completionDelegate is called when the operation finishes.
         /// </summary>
-        public void StartSendStatusFromServer(Status status, AsyncCompletionDelegate<object> completionDelegate)
+        public void StartSendStatusFromServer(Status status, Metadata trailers, AsyncCompletionDelegate<object> completionDelegate)
         {
             lock (myLock)
             {
                 Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
                 CheckSendingAllowed();
 
-                call.StartSendStatusFromServer(status, HandleHalfclosed);
+                using (var metadataArray = MetadataArraySafeHandle.Create(trailers))
+                {
+                    call.StartSendStatusFromServer(status, HandleHalfclosed, metadataArray);
+                }
                 halfcloseRequested = true;
                 readingDone = true;
                 sendCompletionDelegate = completionDelegate;
diff --git a/src/csharp/Grpc.Core/Internal/BatchContextSafeHandle.cs b/src/csharp/Grpc.Core/Internal/BatchContextSafeHandle.cs
index 861cbbe4c6..6a2add54db 100644
--- a/src/csharp/Grpc.Core/Internal/BatchContextSafeHandle.cs
+++ b/src/csharp/Grpc.Core/Internal/BatchContextSafeHandle.cs
@@ -38,7 +38,6 @@ using Grpc.Core;
 namespace Grpc.Core.Internal
 {
     /// <summary>
-    /// Not owned version of 
     /// grpcsharp_batch_context
     /// </summary>
     internal class BatchContextSafeHandle : SafeHandleZeroIsInvalid
@@ -47,6 +46,9 @@ namespace Grpc.Core.Internal
         static extern BatchContextSafeHandle grpcsharp_batch_context_create();
 
         [DllImport("grpc_csharp_ext.dll")]
+        static extern IntPtr grpcsharp_batch_context_recv_initial_metadata(BatchContextSafeHandle ctx);
+
+        [DllImport("grpc_csharp_ext.dll")]
         static extern IntPtr grpcsharp_batch_context_recv_message_length(BatchContextSafeHandle ctx);
 
         [DllImport("grpc_csharp_ext.dll")]
@@ -59,12 +61,24 @@ namespace Grpc.Core.Internal
         static extern IntPtr grpcsharp_batch_context_recv_status_on_client_details(BatchContextSafeHandle ctx);  // returns const char*
 
         [DllImport("grpc_csharp_ext.dll")]
+        static extern IntPtr grpcsharp_batch_context_recv_status_on_client_trailing_metadata(BatchContextSafeHandle ctx);
+
+        [DllImport("grpc_csharp_ext.dll")]
         static extern CallSafeHandle grpcsharp_batch_context_server_rpc_new_call(BatchContextSafeHandle ctx);
 
         [DllImport("grpc_csharp_ext.dll")]
         static extern IntPtr grpcsharp_batch_context_server_rpc_new_method(BatchContextSafeHandle ctx);  // returns const char*
 
         [DllImport("grpc_csharp_ext.dll")]
+        static extern IntPtr grpcsharp_batch_context_server_rpc_new_host(BatchContextSafeHandle ctx);  // returns const char*
+
+        [DllImport("grpc_csharp_ext.dll")]
+        static extern Timespec grpcsharp_batch_context_server_rpc_new_deadline(BatchContextSafeHandle ctx);
+
+        [DllImport("grpc_csharp_ext.dll")]
+        static extern IntPtr grpcsharp_batch_context_server_rpc_new_request_metadata(BatchContextSafeHandle ctx);
+
+        [DllImport("grpc_csharp_ext.dll")]
         static extern int grpcsharp_batch_context_recv_close_on_server_cancelled(BatchContextSafeHandle ctx);
 
         [DllImport("grpc_csharp_ext.dll")]
@@ -87,13 +101,26 @@ namespace Grpc.Core.Internal
             }
         }
 
-        public Status GetReceivedStatus()
+        // Gets data of recv_initial_metadata completion.
+        public Metadata GetReceivedInitialMetadata()
+        {
+            IntPtr metadataArrayPtr = grpcsharp_batch_context_recv_initial_metadata(this);
+            return MetadataArraySafeHandle.ReadMetadataFromPtrUnsafe(metadataArrayPtr);
+        }
+            
+        // Gets data of recv_status_on_client completion.
+        public ClientSideStatus GetReceivedStatusOnClient()
         {
-            // TODO: can the native method return string directly?
             string details = Marshal.PtrToStringAnsi(grpcsharp_batch_context_recv_status_on_client_details(this));
-            return new Status(grpcsharp_batch_context_recv_status_on_client_status(this), details);
+            var status = new Status(grpcsharp_batch_context_recv_status_on_client_status(this), details);
+
+            IntPtr metadataArrayPtr = grpcsharp_batch_context_recv_status_on_client_trailing_metadata(this);
+            var metadata = MetadataArraySafeHandle.ReadMetadataFromPtrUnsafe(metadataArrayPtr);
+
+            return new ClientSideStatus(status, metadata);
         }
 
+        // Gets data of recv_message completion.
         public byte[] GetReceivedMessage()
         {
             IntPtr len = grpcsharp_batch_context_recv_message_length(this);
@@ -106,16 +133,22 @@ namespace Grpc.Core.Internal
             return data;
         }
 
-        public CallSafeHandle GetServerRpcNewCall()
+        // Gets data of server_rpc_new completion.
+        public ServerRpcNew GetServerRpcNew()
         {
-            return grpcsharp_batch_context_server_rpc_new_call(this);
-        }
+            var call = grpcsharp_batch_context_server_rpc_new_call(this);
 
-        public string GetServerRpcNewMethod()
-        {
-            return Marshal.PtrToStringAnsi(grpcsharp_batch_context_server_rpc_new_method(this));
+            var method = Marshal.PtrToStringAnsi(grpcsharp_batch_context_server_rpc_new_method(this));
+            var host = Marshal.PtrToStringAnsi(grpcsharp_batch_context_server_rpc_new_host(this));
+            var deadline = grpcsharp_batch_context_server_rpc_new_deadline(this);
+
+            IntPtr metadataArrayPtr = grpcsharp_batch_context_server_rpc_new_request_metadata(this);
+            var metadata = MetadataArraySafeHandle.ReadMetadataFromPtrUnsafe(metadataArrayPtr);
+
+            return new ServerRpcNew(call, method, host, deadline, metadata);
         }
 
+        // Gets data of receive_close_on_server completion.
         public bool GetReceivedCloseOnServerCancelled()
         {
             return grpcsharp_batch_context_recv_close_on_server_cancelled(this) != 0;
@@ -127,4 +160,97 @@ namespace Grpc.Core.Internal
             return true;
         }
     }
+
+    /// <summary>
+    /// Status + metadata received on client side when call finishes.
+    /// (when receive_status_on_client operation finishes).
+    /// </summary>
+    internal struct ClientSideStatus
+    {
+        readonly Status status;
+        readonly Metadata trailers;
+
+        public ClientSideStatus(Status status, Metadata trailers)
+        {
+            this.status = status;
+            this.trailers = trailers;
+        }
+
+        public Status Status
+        {
+            get
+            {
+                return this.status;
+            }    
+        }
+
+        public Metadata Trailers
+        {
+            get
+            {
+                return this.trailers;
+            }
+        }
+    }
+
+    /// <summary>
+    /// Details of a newly received RPC.
+    /// </summary>
+    internal struct ServerRpcNew
+    {
+        readonly CallSafeHandle call;
+        readonly string method;
+        readonly string host;
+        readonly Timespec deadline;
+        readonly Metadata requestMetadata;
+
+        public ServerRpcNew(CallSafeHandle call, string method, string host, Timespec deadline, Metadata requestMetadata)
+        {
+            this.call = call;
+            this.method = method;
+            this.host = host;
+            this.deadline = deadline;
+            this.requestMetadata = requestMetadata;
+        }
+
+        public CallSafeHandle Call
+        {
+            get
+            {
+                return this.call;
+            }
+        }
+
+        public string Method
+        {
+            get
+            {
+                return this.method;
+            }
+        }
+
+        public string Host
+        {
+            get
+            {
+                return this.host;
+            }
+        }
+
+        public Timespec Deadline
+        {
+            get
+            {
+                return this.deadline;
+            }
+        }
+
+        public Metadata RequestMetadata
+        {
+            get
+            {
+                return this.requestMetadata;
+            }
+        }
+    }
 }
\ No newline at end of file
diff --git a/src/csharp/Grpc.Core/Internal/CallSafeHandle.cs b/src/csharp/Grpc.Core/Internal/CallSafeHandle.cs
index 3b246ac01b..19dbb83f24 100644
--- a/src/csharp/Grpc.Core/Internal/CallSafeHandle.cs
+++ b/src/csharp/Grpc.Core/Internal/CallSafeHandle.cs
@@ -81,7 +81,7 @@ namespace Grpc.Core.Internal
 
         [DllImport("grpc_csharp_ext.dll")]
         static extern GRPCCallError grpcsharp_call_send_status_from_server(CallSafeHandle call, 
-            BatchContextSafeHandle ctx, StatusCode statusCode, string statusMessage);
+            BatchContextSafeHandle ctx, StatusCode statusCode, string statusMessage, MetadataArraySafeHandle metadataArray);
 
         [DllImport("grpc_csharp_ext.dll")]
         static extern GRPCCallError grpcsharp_call_recv_message(CallSafeHandle call,
@@ -159,11 +159,11 @@ namespace Grpc.Core.Internal
             grpcsharp_call_send_close_from_client(this, ctx).CheckOk();
         }
 
-        public void StartSendStatusFromServer(Status status, BatchCompletionDelegate callback)
+        public void StartSendStatusFromServer(Status status, BatchCompletionDelegate callback, MetadataArraySafeHandle metadataArray)
         {
             var ctx = BatchContextSafeHandle.Create();
             completionRegistry.RegisterBatchCompletion(ctx, callback);
-            grpcsharp_call_send_status_from_server(this, ctx, status.StatusCode, status.Detail).CheckOk();
+            grpcsharp_call_send_status_from_server(this, ctx, status.StatusCode, status.Detail, metadataArray).CheckOk();
         }
 
         public void StartReceiveMessage(BatchCompletionDelegate callback)
diff --git a/src/csharp/Grpc.Core/Internal/MetadataArraySafeHandle.cs b/src/csharp/Grpc.Core/Internal/MetadataArraySafeHandle.cs
index 80aa7f5603..427c16fac6 100644
--- a/src/csharp/Grpc.Core/Internal/MetadataArraySafeHandle.cs
+++ b/src/csharp/Grpc.Core/Internal/MetadataArraySafeHandle.cs
@@ -46,12 +46,24 @@ namespace Grpc.Core.Internal
         static extern void grpcsharp_metadata_array_add(MetadataArraySafeHandle array, string key, byte[] value, UIntPtr valueLength);
 
         [DllImport("grpc_csharp_ext.dll")]
+        static extern UIntPtr grpcsharp_metadata_array_count(IntPtr metadataArray);
+
+        [DllImport("grpc_csharp_ext.dll")]
+        static extern IntPtr grpcsharp_metadata_array_get_key(IntPtr metadataArray, UIntPtr index);
+
+        [DllImport("grpc_csharp_ext.dll")]
+        static extern IntPtr grpcsharp_metadata_array_get_value(IntPtr metadataArray, UIntPtr index);
+
+        [DllImport("grpc_csharp_ext.dll")]
+        static extern UIntPtr grpcsharp_metadata_array_get_value_length(IntPtr metadataArray, UIntPtr index);
+
+        [DllImport("grpc_csharp_ext.dll")]
         static extern void grpcsharp_metadata_array_destroy_full(IntPtr array);
 
         private MetadataArraySafeHandle()
         {
         }
-
+            
         public static MetadataArraySafeHandle Create(Metadata metadata)
         {
             // TODO(jtattermusch): we might wanna check that the metadata is readonly 
@@ -63,6 +75,38 @@ namespace Grpc.Core.Internal
             return metadataArray;
         }
 
+        /// <summary>
+        /// Reads metadata from pointer to grpc_metadata_array
+        /// </summary>
+        public static Metadata ReadMetadataFromPtrUnsafe(IntPtr metadataArray)
+        {
+            if (metadataArray == IntPtr.Zero)
+            {
+                return null;
+            }
+
+            ulong count = grpcsharp_metadata_array_count(metadataArray).ToUInt64();
+
+            var metadata = new Metadata();
+            for (ulong i = 0; i < count; i++)
+            {
+                var index = new UIntPtr(i);
+                string key = Marshal.PtrToStringAnsi(grpcsharp_metadata_array_get_key(metadataArray, index));
+                var bytes = new byte[grpcsharp_metadata_array_get_value_length(metadataArray, index).ToUInt64()];
+                Marshal.Copy(grpcsharp_metadata_array_get_value(metadataArray, index), bytes, 0, bytes.Length);
+                metadata.Add(new Metadata.Entry(key, bytes));
+            }
+            return metadata;
+        }
+
+        internal IntPtr Handle
+        {
+            get
+            {
+                return handle;
+            }
+        }
+
         protected override bool ReleaseHandle()
         {
             grpcsharp_metadata_array_destroy_full(handle);
diff --git a/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs b/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
index 594e46b159..3680b1e791 100644
--- a/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
+++ b/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
@@ -34,6 +34,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Threading;
 using System.Threading.Tasks;
 using Grpc.Core.Internal;
 using Grpc.Core.Utils;
@@ -42,7 +43,7 @@ namespace Grpc.Core.Internal
 {
     internal interface IServerCallHandler
     {
-        Task HandleCall(string methodName, CallSafeHandle call, GrpcEnvironment environment);
+        Task HandleCall(ServerRpcNew newRpc, GrpcEnvironment environment);
     }
 
     internal class UnaryServerCallHandler<TRequest, TResponse> : IServerCallHandler
@@ -58,27 +59,28 @@ namespace Grpc.Core.Internal
             this.handler = handler;
         }
 
-        public async Task HandleCall(string methodName, CallSafeHandle call, GrpcEnvironment environment)
+        public async Task HandleCall(ServerRpcNew newRpc, GrpcEnvironment environment)
         {
             var asyncCall = new AsyncCallServer<TRequest, TResponse>(
                 method.ResponseMarshaller.Serializer,
                 method.RequestMarshaller.Deserializer,
                 environment);
 
-            asyncCall.Initialize(call);
+            asyncCall.Initialize(newRpc.Call);
             var finishedTask = asyncCall.ServerSideCallAsync();
             var requestStream = new ServerRequestStream<TRequest, TResponse>(asyncCall);
             var responseStream = new ServerResponseStream<TRequest, TResponse>(asyncCall);
 
-            Status status = Status.DefaultSuccess;
+            Status status;
+            var context = HandlerUtils.NewContext(newRpc);
             try
             {
                 Preconditions.CheckArgument(await requestStream.MoveNext());
                 var request = requestStream.Current;
                 // TODO(jtattermusch): we need to read the full stream so that native callhandle gets deallocated.
                 Preconditions.CheckArgument(!await requestStream.MoveNext());
-                var context = new ServerCallContext();  // TODO(jtattermusch): initialize the context
-                var result = await handler(context, request);
+                var result = await handler(request, context);
+                status = context.Status;
                 await responseStream.WriteAsync(result);
             } 
             catch (Exception e)
@@ -88,7 +90,7 @@ namespace Grpc.Core.Internal
             }
             try
             {
-                await responseStream.WriteStatusAsync(status);
+                await responseStream.WriteStatusAsync(status, context.ResponseTrailers);
             }
             catch (OperationCanceledException)
             {
@@ -111,28 +113,28 @@ namespace Grpc.Core.Internal
             this.handler = handler;
         }
 
-        public async Task HandleCall(string methodName, CallSafeHandle call, GrpcEnvironment environment)
+        public async Task HandleCall(ServerRpcNew newRpc, GrpcEnvironment environment)
         {
             var asyncCall = new AsyncCallServer<TRequest, TResponse>(
                 method.ResponseMarshaller.Serializer,
                 method.RequestMarshaller.Deserializer,
                 environment);
 
-            asyncCall.Initialize(call);
+            asyncCall.Initialize(newRpc.Call);
             var finishedTask = asyncCall.ServerSideCallAsync();
             var requestStream = new ServerRequestStream<TRequest, TResponse>(asyncCall);
             var responseStream = new ServerResponseStream<TRequest, TResponse>(asyncCall);
 
-            Status status = Status.DefaultSuccess;
+            Status status;
+            var context = HandlerUtils.NewContext(newRpc);
             try
             {
                 Preconditions.CheckArgument(await requestStream.MoveNext());
                 var request = requestStream.Current;
                 // TODO(jtattermusch): we need to read the full stream so that native callhandle gets deallocated.
                 Preconditions.CheckArgument(!await requestStream.MoveNext());
-
-                var context = new ServerCallContext();  // TODO(jtattermusch): initialize the context
-                await handler(context, request, responseStream);
+                await handler(request, responseStream, context);
+                status = context.Status;
             }
             catch (Exception e)
             {
@@ -142,7 +144,7 @@ namespace Grpc.Core.Internal
 
             try
             {
-                await responseStream.WriteStatusAsync(status);
+                await responseStream.WriteStatusAsync(status, context.ResponseTrailers);
             }
             catch (OperationCanceledException)
             {
@@ -165,23 +167,24 @@ namespace Grpc.Core.Internal
             this.handler = handler;
         }
 
-        public async Task HandleCall(string methodName, CallSafeHandle call, GrpcEnvironment environment)
+        public async Task HandleCall(ServerRpcNew newRpc, GrpcEnvironment environment)
         {
             var asyncCall = new AsyncCallServer<TRequest, TResponse>(
                 method.ResponseMarshaller.Serializer,
                 method.RequestMarshaller.Deserializer,
                 environment);
 
-            asyncCall.Initialize(call);
+            asyncCall.Initialize(newRpc.Call);
             var finishedTask = asyncCall.ServerSideCallAsync();
             var requestStream = new ServerRequestStream<TRequest, TResponse>(asyncCall);
             var responseStream = new ServerResponseStream<TRequest, TResponse>(asyncCall);
-            var context = new ServerCallContext();  // TODO(jtattermusch): initialize the context
 
-            Status status = Status.DefaultSuccess;
+            Status status;
+            var context = HandlerUtils.NewContext(newRpc);
             try
             {
-                var result = await handler(context, requestStream);
+                var result = await handler(requestStream, context);
+                status = context.Status;
                 try
                 {
                     await responseStream.WriteAsync(result);
@@ -199,7 +202,7 @@ namespace Grpc.Core.Internal
 
             try
             {
-                await responseStream.WriteStatusAsync(status);
+                await responseStream.WriteStatusAsync(status, context.ResponseTrailers);
             }
             catch (OperationCanceledException)
             {
@@ -222,23 +225,24 @@ namespace Grpc.Core.Internal
             this.handler = handler;
         }
 
-        public async Task HandleCall(string methodName, CallSafeHandle call, GrpcEnvironment environment)
+        public async Task HandleCall(ServerRpcNew newRpc, GrpcEnvironment environment)
         {
             var asyncCall = new AsyncCallServer<TRequest, TResponse>(
                 method.ResponseMarshaller.Serializer,
                 method.RequestMarshaller.Deserializer,
                 environment);
 
-            asyncCall.Initialize(call);
+            asyncCall.Initialize(newRpc.Call);
             var finishedTask = asyncCall.ServerSideCallAsync();
             var requestStream = new ServerRequestStream<TRequest, TResponse>(asyncCall);
             var responseStream = new ServerResponseStream<TRequest, TResponse>(asyncCall);
-            var context = new ServerCallContext();  // TODO(jtattermusch): initialize the context
 
-            Status status = Status.DefaultSuccess;
+            Status status;
+            var context = HandlerUtils.NewContext(newRpc);
             try
             {
-                await handler(context, requestStream, responseStream);
+                await handler(requestStream, responseStream, context);
+                status = context.Status;
             }
             catch (Exception e)
             {
@@ -247,7 +251,7 @@ namespace Grpc.Core.Internal
             }
             try
             {
-                await responseStream.WriteStatusAsync(status);
+                await responseStream.WriteStatusAsync(status, context.ResponseTrailers);
             }
             catch (OperationCanceledException)
             {
@@ -259,18 +263,19 @@ namespace Grpc.Core.Internal
 
     internal class NoSuchMethodCallHandler : IServerCallHandler
     {
-        public async Task HandleCall(string methodName, CallSafeHandle call, GrpcEnvironment environment)
+        public static readonly NoSuchMethodCallHandler Instance = new NoSuchMethodCallHandler();
+
+        public async Task HandleCall(ServerRpcNew newRpc, GrpcEnvironment environment)
         {
             // We don't care about the payload type here.
             var asyncCall = new AsyncCallServer<byte[], byte[]>(
                 (payload) => payload, (payload) => payload, environment);
             
-            asyncCall.Initialize(call);
+            asyncCall.Initialize(newRpc.Call);
             var finishedTask = asyncCall.ServerSideCallAsync();
-            var requestStream = new ServerRequestStream<byte[], byte[]>(asyncCall);
             var responseStream = new ServerResponseStream<byte[], byte[]>(asyncCall);
 
-            await responseStream.WriteStatusAsync(new Status(StatusCode.Unimplemented, "No such method."));
+            await responseStream.WriteStatusAsync(new Status(StatusCode.Unimplemented, "No such method."), Metadata.Empty);
             await finishedTask;
         }
     }
@@ -279,8 +284,22 @@ namespace Grpc.Core.Internal
     {
         public static Status StatusFromException(Exception e)
         {
+            var rpcException = e as RpcException;
+            if (rpcException != null)
+            {
+                // use the status thrown by handler.
+                return rpcException.Status;
+            }
+
             // TODO(jtattermusch): what is the right status code here?
             return new Status(StatusCode.Unknown, "Exception was thrown by handler.");
         }
+
+        public static ServerCallContext NewContext(ServerRpcNew newRpc)
+        {
+            return new ServerCallContext(
+                newRpc.Method, newRpc.Host, newRpc.Deadline.ToDateTime(),
+                newRpc.RequestMetadata, CancellationToken.None);
+        }
     }
 }
diff --git a/src/csharp/Grpc.Core/Internal/ServerResponseStream.cs b/src/csharp/Grpc.Core/Internal/ServerResponseStream.cs
index a2d77dd5b7..756dcee87f 100644
--- a/src/csharp/Grpc.Core/Internal/ServerResponseStream.cs
+++ b/src/csharp/Grpc.Core/Internal/ServerResponseStream.cs
@@ -56,10 +56,10 @@ namespace Grpc.Core.Internal
             return taskSource.Task;
         }
 
-        public Task WriteStatusAsync(Status status)
+        public Task WriteStatusAsync(Status status, Metadata trailers)
         {
             var taskSource = new AsyncCompletionTaskSource<object>();
-            call.StartSendStatusFromServer(status, taskSource.CompletionDelegate);
+            call.StartSendStatusFromServer(status, trailers, taskSource.CompletionDelegate);
             return taskSource.Task;
         }
     }
diff --git a/src/csharp/Grpc.Core/Internal/Timespec.cs b/src/csharp/Grpc.Core/Internal/Timespec.cs
index de783f5a4b..da2819f14d 100644
--- a/src/csharp/Grpc.Core/Internal/Timespec.cs
+++ b/src/csharp/Grpc.Core/Internal/Timespec.cs
@@ -43,6 +43,8 @@ namespace Grpc.Core.Internal
         const int NanosPerSecond = 1000 * 1000 * 1000;
         const int NanosPerTick = 100;
 
+        static readonly DateTime UnixEpoch = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
+
         [DllImport("grpc_csharp_ext.dll")]
         static extern Timespec gprsharp_now();
 
@@ -52,6 +54,13 @@ namespace Grpc.Core.Internal
         [DllImport("grpc_csharp_ext.dll")]
         static extern int gprsharp_sizeof_timespec();
 
+        public Timespec(IntPtr tv_sec, int tv_nsec)
+        {
+            this.tv_sec = tv_sec;
+            this.tv_nsec = tv_nsec;
+            this.clock_type = GPRClockType.Realtime;
+        }
+
         // NOTE: on linux 64bit  sizeof(gpr_timespec) = 16, on windows 32bit sizeof(gpr_timespec) = 8
         // so IntPtr seems to have the right size to work on both.
         public System.IntPtr tv_sec;
@@ -76,6 +85,11 @@ namespace Grpc.Core.Internal
                 return gprsharp_now();
             }
         }
+            
+        public DateTime ToDateTime()
+        {
+            return UnixEpoch.AddTicks(tv_sec.ToInt64() * (NanosPerSecond / NanosPerTick) + tv_nsec / NanosPerTick);
+        }
 
         internal static int NativeSize
         {
diff --git a/src/csharp/Grpc.Core/Metadata.cs b/src/csharp/Grpc.Core/Metadata.cs
index 4552d39d88..2f308cbb11 100644
--- a/src/csharp/Grpc.Core/Metadata.cs
+++ b/src/csharp/Grpc.Core/Metadata.cs
@@ -220,6 +220,11 @@ namespace Grpc.Core
                     return value;
                 }
             }
+                
+            public override string ToString()
+            {
+                return string.Format("[Entry: key={0}, value={1}]", Key, Value);
+            }
         }
     }
 }
diff --git a/src/csharp/Grpc.Core/Server.cs b/src/csharp/Grpc.Core/Server.cs
index cbf77196cf..fd30735359 100644
--- a/src/csharp/Grpc.Core/Server.cs
+++ b/src/csharp/Grpc.Core/Server.cs
@@ -53,6 +53,7 @@ namespace Grpc.Core
         public const int PickUnusedPort = 0;
 
         readonly GrpcEnvironment environment;
+        readonly List<ChannelOption> options;
         readonly ServerSafeHandle handle;
         readonly object myLock = new object();
 
@@ -69,7 +70,8 @@ namespace Grpc.Core
         public Server(IEnumerable<ChannelOption> options = null)
         {
             this.environment = GrpcEnvironment.GetInstance();
-            using (var channelArgs = ChannelOptions.CreateChannelArgs(options))
+            this.options = options != null ? new List<ChannelOption>(options) : new List<ChannelOption>();
+            using (var channelArgs = ChannelOptions.CreateChannelArgs(this.options))
             {
                 this.handle = ServerSafeHandle.NewServer(environment.CompletionQueue, channelArgs);
             }
@@ -218,16 +220,16 @@ namespace Grpc.Core
         /// <summary>
         /// Selects corresponding handler for given call and handles the call.
         /// </summary>
-        private async Task InvokeCallHandler(CallSafeHandle call, string method)
+        private async Task HandleCallAsync(ServerRpcNew newRpc)
         {
             try
             {
                 IServerCallHandler callHandler;
-                if (!callHandlers.TryGetValue(method, out callHandler))
+                if (!callHandlers.TryGetValue(newRpc.Method, out callHandler))
                 {
-                    callHandler = new NoSuchMethodCallHandler();
+                    callHandler = NoSuchMethodCallHandler.Instance;
                 }
-                await callHandler.HandleCall(method, call, environment);
+                await callHandler.HandleCall(newRpc, environment);
             }
             catch (Exception e)
             {
@@ -240,15 +242,15 @@ namespace Grpc.Core
         /// </summary>
         private void HandleNewServerRpc(bool success, BatchContextSafeHandle ctx)
         {
-            // TODO: handle error
-
-            CallSafeHandle call = ctx.GetServerRpcNewCall();
-            string method = ctx.GetServerRpcNewMethod();
-
-            // after server shutdown, the callback returns with null call
-            if (!call.IsInvalid)
+            if (success)
             {
-                Task.Run(async () => await InvokeCallHandler(call, method));
+                ServerRpcNew newRpc = ctx.GetServerRpcNew();
+
+                // after server shutdown, the callback returns with null call
+                if (!newRpc.Call.IsInvalid)
+                {
+                    Task.Run(async () => await HandleCallAsync(newRpc));
+                }
             }
 
             AllowOneRpc();
diff --git a/src/csharp/Grpc.Core/ServerCallContext.cs b/src/csharp/Grpc.Core/ServerCallContext.cs
index bc9a499c51..17a2eefd07 100644
--- a/src/csharp/Grpc.Core/ServerCallContext.cs
+++ b/src/csharp/Grpc.Core/ServerCallContext.cs
@@ -33,6 +33,7 @@
 
 using System;
 using System.Runtime.CompilerServices;
+using System.Threading;
 using System.Threading.Tasks;
 
 namespace Grpc.Core
@@ -42,14 +43,93 @@ namespace Grpc.Core
     /// </summary>
     public sealed class ServerCallContext
     {
-        // TODO(jtattermusch): add cancellationToken
+        // TODO(jtattermusch): expose method to send initial metadata back to client
 
-        // TODO(jtattermusch): add deadline info
+        private readonly string method;
+        private readonly string host;
+        private readonly DateTime deadline;
+        private readonly Metadata requestHeaders;
+        private readonly CancellationToken cancellationToken;
+        private readonly Metadata responseTrailers = new Metadata();
 
-        // TODO(jtattermusch): expose initial metadata sent by client for reading
+        private Status status = Status.DefaultSuccess;
 
-        // TODO(jtattermusch): expose method to send initial metadata back to client
+        public ServerCallContext(string method, string host, DateTime deadline, Metadata requestHeaders, CancellationToken cancellationToken)
+        {
+            this.method = method;
+            this.host = host;
+            this.deadline = deadline;
+            this.requestHeaders = requestHeaders;
+            this.cancellationToken = cancellationToken;
+        }
+            
+        /// <summary> Name of method called in this RPC. </summary>
+        public string Method
+        {
+            get
+            {
+                return this.method;
+            }
+        }
+
+        /// <summary> Name of host called in this RPC. </summary>
+        public string Host
+        {
+            get
+            {
+                return this.host;
+            }
+        }
+
+        /// <summary> Deadline for this RPC. </summary>
+        public DateTime Deadline
+        {
+            get
+            {
+                return this.deadline;
+            }
+        }
+
+        /// <summary> Initial metadata sent by client. </summary>
+        public Metadata RequestHeaders
+        {
+            get
+            {
+                return this.requestHeaders;
+            }
+        }
+
+        // TODO(jtattermusch): support signalling cancellation.
+        /// <summary> Cancellation token signals when call is cancelled. </summary>
+        public CancellationToken CancellationToken
+        {
+            get
+            {
+                return this.cancellationToken;
+            }
+        }
+
+        /// <summary> Trailers to send back to client after RPC finishes.</summary>
+        public Metadata ResponseTrailers
+        {
+            get
+            {
+                return this.responseTrailers;
+            }
+        }
+
+        /// <summary> Status to send back to client after RPC finishes.</summary>
+        public Status Status
+        {
+            get
+            {
+                return this.status;
+            }
 
-        // TODO(jtattermusch): allow setting status and trailing metadata to send after handler completes.
+            set
+            {
+                status = value;
+            }
+        }
     }
 }
diff --git a/src/csharp/Grpc.Core/ServerMethods.cs b/src/csharp/Grpc.Core/ServerMethods.cs
index 377b78eb30..d457770203 100644
--- a/src/csharp/Grpc.Core/ServerMethods.cs
+++ b/src/csharp/Grpc.Core/ServerMethods.cs
@@ -42,28 +42,28 @@ namespace Grpc.Core
     /// <summary>
     /// Server-side handler for unary call.
     /// </summary>
-    public delegate Task<TResponse> UnaryServerMethod<TRequest, TResponse>(ServerCallContext context, TRequest request)
+    public delegate Task<TResponse> UnaryServerMethod<TRequest, TResponse>(TRequest request, ServerCallContext context)
         where TRequest : class
         where TResponse : class;
 
     /// <summary>
     /// Server-side handler for client streaming call.
     /// </summary>
-    public delegate Task<TResponse> ClientStreamingServerMethod<TRequest, TResponse>(ServerCallContext context, IAsyncStreamReader<TRequest> requestStream)
+    public delegate Task<TResponse> ClientStreamingServerMethod<TRequest, TResponse>(IAsyncStreamReader<TRequest> requestStream, ServerCallContext context)
         where TRequest : class
         where TResponse : class;
 
     /// <summary>
     /// Server-side handler for server streaming call.
     /// </summary>
-    public delegate Task ServerStreamingServerMethod<TRequest, TResponse>(ServerCallContext context, TRequest request, IServerStreamWriter<TResponse> responseStream)
+    public delegate Task ServerStreamingServerMethod<TRequest, TResponse>(TRequest request, IServerStreamWriter<TResponse> responseStream, ServerCallContext context)
         where TRequest : class
         where TResponse : class;
 
     /// <summary>
     /// Server-side handler for bidi streaming call.
     /// </summary>
-    public delegate Task DuplexStreamingServerMethod<TRequest, TResponse>(ServerCallContext context, IAsyncStreamReader<TRequest> requestStream, IServerStreamWriter<TResponse> responseStream)
+    public delegate Task DuplexStreamingServerMethod<TRequest, TResponse>(IAsyncStreamReader<TRequest> requestStream, IServerStreamWriter<TResponse> responseStream, ServerCallContext context)
         where TRequest : class
         where TResponse : class;
 }
diff --git a/src/csharp/Grpc.Core/Version.cs b/src/csharp/Grpc.Core/Version.cs
index f1db1f6157..b5cb652945 100644
--- a/src/csharp/Grpc.Core/Version.cs
+++ b/src/csharp/Grpc.Core/Version.cs
@@ -2,4 +2,4 @@ using System.Reflection;
 using System.Runtime.CompilerServices;
 
 // The current version of gRPC C#.
-[assembly: AssemblyVersion("0.6.0.*")]
+[assembly: AssemblyVersion(Grpc.Core.VersionInfo.CurrentVersion + ".*")]
diff --git a/src/csharp/Grpc.Core/VersionInfo.cs b/src/csharp/Grpc.Core/VersionInfo.cs
new file mode 100644
index 0000000000..656a3d47bb
--- /dev/null
+++ b/src/csharp/Grpc.Core/VersionInfo.cs
@@ -0,0 +1,13 @@
+using System.Reflection;
+using System.Runtime.CompilerServices;
+
+namespace Grpc.Core
+{
+    public static class VersionInfo
+    {
+        /// <summary>
+        /// Current version of gRPC
+        /// </summary>
+        public const string CurrentVersion = "0.6.0";
+    }
+}
diff --git a/src/csharp/Grpc.Examples.Tests/MathClientServerTests.cs b/src/csharp/Grpc.Examples.Tests/MathClientServerTests.cs
index e7c4b33120..7a957c5b6f 100644
--- a/src/csharp/Grpc.Examples.Tests/MathClientServerTests.cs
+++ b/src/csharp/Grpc.Examples.Tests/MathClientServerTests.cs
@@ -144,7 +144,7 @@ namespace math.Tests
                              n => Num.CreateBuilder().SetNum_(n).Build());
 
                     await call.RequestStream.WriteAll(numbers);
-                    var result = await call.Result;
+                    var result = await call.ResponseAsync;
                     Assert.AreEqual(60, result.Num_);
                 }
             }).Wait();
diff --git a/src/csharp/Grpc.Examples/MathExamples.cs b/src/csharp/Grpc.Examples/MathExamples.cs
index 7deb651689..06d81a4d83 100644
--- a/src/csharp/Grpc.Examples/MathExamples.cs
+++ b/src/csharp/Grpc.Examples/MathExamples.cs
@@ -46,8 +46,7 @@ namespace math
 
         public static async Task DivAsyncExample(Math.IMathClient client)
         {
-            Task<DivReply> resultTask = client.DivAsync(new DivArgs.Builder { Dividend = 4, Divisor = 5 }.Build());
-            DivReply result = await resultTask;
+            DivReply result = await client.DivAsync(new DivArgs.Builder { Dividend = 4, Divisor = 5 }.Build());
             Console.WriteLine("DivAsync Result: " + result);
         }
 
@@ -72,7 +71,7 @@ namespace math
             using (var call = client.Sum())
             {
                 await call.RequestStream.WriteAll(numbers);
-                Console.WriteLine("Sum Result: " + await call.Result);
+                Console.WriteLine("Sum Result: " + await call.ResponseAsync);
             }
         }
 
@@ -104,7 +103,7 @@ namespace math
             using (var sumCall = client.Sum())
             {
                 await sumCall.RequestStream.WriteAll(numbers);
-                sum = await sumCall.Result;
+                sum = await sumCall.ResponseAsync;
             }
 
             DivReply result = await client.DivAsync(new DivArgs.Builder { Dividend = sum.Num_, Divisor = numbers.Count }.Build());
diff --git a/src/csharp/Grpc.Examples/MathGrpc.cs b/src/csharp/Grpc.Examples/MathGrpc.cs
index 1805972ce3..ef787cf1d8 100644
--- a/src/csharp/Grpc.Examples/MathGrpc.cs
+++ b/src/csharp/Grpc.Examples/MathGrpc.cs
@@ -45,7 +45,7 @@ namespace math {
     public interface IMathClient
     {
       global::math.DivReply Div(global::math.DivArgs request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
-      Task<global::math.DivReply> DivAsync(global::math.DivArgs request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
+      AsyncUnaryCall<global::math.DivReply> DivAsync(global::math.DivArgs request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
       AsyncDuplexStreamingCall<global::math.DivArgs, global::math.DivReply> DivMany(Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
       AsyncServerStreamingCall<global::math.Num> Fib(global::math.FibArgs request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
       AsyncClientStreamingCall<global::math.Num, global::math.Num> Sum(Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
@@ -54,10 +54,10 @@ namespace math {
     // server-side interface
     public interface IMath
     {
-      Task<global::math.DivReply> Div(ServerCallContext context, global::math.DivArgs request);
-      Task DivMany(ServerCallContext context, IAsyncStreamReader<global::math.DivArgs> requestStream, IServerStreamWriter<global::math.DivReply> responseStream);
-      Task Fib(ServerCallContext context, global::math.FibArgs request, IServerStreamWriter<global::math.Num> responseStream);
-      Task<global::math.Num> Sum(ServerCallContext context, IAsyncStreamReader<global::math.Num> requestStream);
+      Task<global::math.DivReply> Div(global::math.DivArgs request, ServerCallContext context);
+      Task DivMany(IAsyncStreamReader<global::math.DivArgs> requestStream, IServerStreamWriter<global::math.DivReply> responseStream, ServerCallContext context);
+      Task Fib(global::math.FibArgs request, IServerStreamWriter<global::math.Num> responseStream, ServerCallContext context);
+      Task<global::math.Num> Sum(IAsyncStreamReader<global::math.Num> requestStream, ServerCallContext context);
     }
 
     // client stub
@@ -71,7 +71,7 @@ namespace math {
         var call = CreateCall(__ServiceName, __Method_Div, headers);
         return Calls.BlockingUnaryCall(call, request, cancellationToken);
       }
-      public Task<global::math.DivReply> DivAsync(global::math.DivArgs request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken))
+      public AsyncUnaryCall<global::math.DivReply> DivAsync(global::math.DivArgs request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken))
       {
         var call = CreateCall(__ServiceName, __Method_Div, headers);
         return Calls.AsyncUnaryCall(call, request, cancellationToken);
diff --git a/src/csharp/Grpc.Examples/MathServiceImpl.cs b/src/csharp/Grpc.Examples/MathServiceImpl.cs
index e247ac9d73..3dd0f53a0d 100644
--- a/src/csharp/Grpc.Examples/MathServiceImpl.cs
+++ b/src/csharp/Grpc.Examples/MathServiceImpl.cs
@@ -45,12 +45,12 @@ namespace math
     /// </summary>
     public class MathServiceImpl : Math.IMath
     {
-        public Task<DivReply> Div(ServerCallContext context, DivArgs request)
+        public Task<DivReply> Div(DivArgs request, ServerCallContext context)
         {
             return Task.FromResult(DivInternal(request));
         }
 
-        public async Task Fib(ServerCallContext context, FibArgs request, IServerStreamWriter<Num> responseStream)
+        public async Task Fib(FibArgs request, IServerStreamWriter<Num> responseStream, ServerCallContext context)
         {
             if (request.Limit <= 0)
             {
@@ -67,7 +67,7 @@ namespace math
             }
         }
 
-        public async Task<Num> Sum(ServerCallContext context, IAsyncStreamReader<Num> requestStream)
+        public async Task<Num> Sum(IAsyncStreamReader<Num> requestStream, ServerCallContext context)
         {
             long sum = 0;
             await requestStream.ForEach(async num =>
@@ -77,7 +77,7 @@ namespace math
             return Num.CreateBuilder().SetNum_(sum).Build();
         }
 
-        public async Task DivMany(ServerCallContext context, IAsyncStreamReader<DivArgs> requestStream, IServerStreamWriter<DivReply> responseStream)
+        public async Task DivMany(IAsyncStreamReader<DivArgs> requestStream, IServerStreamWriter<DivReply> responseStream, ServerCallContext context)
         {
             await requestStream.ForEach(async divArgs =>
             {
diff --git a/src/csharp/Grpc.HealthCheck.Tests/HealthClientServerTest.cs b/src/csharp/Grpc.HealthCheck.Tests/HealthClientServerTest.cs
index 73ff0e74b5..bc14a0a62f 100644
--- a/src/csharp/Grpc.HealthCheck.Tests/HealthClientServerTest.cs
+++ b/src/csharp/Grpc.HealthCheck.Tests/HealthClientServerTest.cs
@@ -87,9 +87,7 @@ namespace Grpc.HealthCheck.Tests
         [Test]
         public void ServiceDoesntExist()
         {
-            // TODO(jtattermusch): currently, this returns wrong status code, because we don't enable sending arbitrary status code from
-            // server handlers yet.
-            Assert.Throws(typeof(RpcException), () => client.Check(HealthCheckRequest.CreateBuilder().SetHost("").SetService("nonexistent.service").Build()));
+            Assert.Throws(Is.TypeOf(typeof(RpcException)).And.Property("Status").Property("StatusCode").EqualTo(StatusCode.NotFound), () => client.Check(HealthCheckRequest.CreateBuilder().SetHost("").SetService("nonexistent.service").Build()));
         }
 
         // TODO(jtattermusch): add test with timeout once timeouts are supported
diff --git a/src/csharp/Grpc.HealthCheck.Tests/HealthServiceImplTest.cs b/src/csharp/Grpc.HealthCheck.Tests/HealthServiceImplTest.cs
index 9b7c4f2140..7184415655 100644
--- a/src/csharp/Grpc.HealthCheck.Tests/HealthServiceImplTest.cs
+++ b/src/csharp/Grpc.HealthCheck.Tests/HealthServiceImplTest.cs
@@ -101,7 +101,7 @@ namespace Grpc.HealthCheck.Tests
 
         private static HealthCheckResponse.Types.ServingStatus GetStatusHelper(HealthServiceImpl impl, string host, string service)
         {
-            return impl.Check(null, HealthCheckRequest.CreateBuilder().SetHost(host).SetService(service).Build()).Result.Status;
+            return impl.Check(HealthCheckRequest.CreateBuilder().SetHost(host).SetService(service).Build(), null).Result.Status;
         }
     }
 }
diff --git a/src/csharp/Grpc.HealthCheck/HealthGrpc.cs b/src/csharp/Grpc.HealthCheck/HealthGrpc.cs
index 3aebdcb557..217127eca7 100644
--- a/src/csharp/Grpc.HealthCheck/HealthGrpc.cs
+++ b/src/csharp/Grpc.HealthCheck/HealthGrpc.cs
@@ -25,13 +25,13 @@ namespace Grpc.Health.V1Alpha {
     public interface IHealthClient
     {
       global::Grpc.Health.V1Alpha.HealthCheckResponse Check(global::Grpc.Health.V1Alpha.HealthCheckRequest request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
-      Task<global::Grpc.Health.V1Alpha.HealthCheckResponse> CheckAsync(global::Grpc.Health.V1Alpha.HealthCheckRequest request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
+      AsyncUnaryCall<global::Grpc.Health.V1Alpha.HealthCheckResponse> CheckAsync(global::Grpc.Health.V1Alpha.HealthCheckRequest request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
     }
 
     // server-side interface
     public interface IHealth
     {
-      Task<global::Grpc.Health.V1Alpha.HealthCheckResponse> Check(ServerCallContext context, global::Grpc.Health.V1Alpha.HealthCheckRequest request);
+      Task<global::Grpc.Health.V1Alpha.HealthCheckResponse> Check(global::Grpc.Health.V1Alpha.HealthCheckRequest request, ServerCallContext context);
     }
 
     // client stub
@@ -45,7 +45,7 @@ namespace Grpc.Health.V1Alpha {
         var call = CreateCall(__ServiceName, __Method_Check, headers);
         return Calls.BlockingUnaryCall(call, request, cancellationToken);
       }
-      public Task<global::Grpc.Health.V1Alpha.HealthCheckResponse> CheckAsync(global::Grpc.Health.V1Alpha.HealthCheckRequest request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken))
+      public AsyncUnaryCall<global::Grpc.Health.V1Alpha.HealthCheckResponse> CheckAsync(global::Grpc.Health.V1Alpha.HealthCheckRequest request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken))
       {
         var call = CreateCall(__ServiceName, __Method_Check, headers);
         return Calls.AsyncUnaryCall(call, request, cancellationToken);
diff --git a/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs b/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs
index db3a2a0942..3c3b9c35f1 100644
--- a/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs
+++ b/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs
@@ -95,7 +95,7 @@ namespace Grpc.HealthCheck
             }
         }
 
-        public Task<HealthCheckResponse> Check(ServerCallContext context, HealthCheckRequest request)
+        public Task<HealthCheckResponse> Check(HealthCheckRequest request, ServerCallContext context)
         {
             lock (myLock)
             {
diff --git a/src/csharp/Grpc.HealthCheck/Settings.StyleCop b/src/csharp/Grpc.HealthCheck/Settings.StyleCop
new file mode 100644
index 0000000000..2942add962
--- /dev/null
+++ b/src/csharp/Grpc.HealthCheck/Settings.StyleCop
@@ -0,0 +1,10 @@
+<StyleCopSettings Version="105">
+  <SourceFileList>
+    <SourceFile>Health.cs</SourceFile>
+    <Settings>
+    <GlobalSettings>
+      <BooleanProperty Name="RulesEnabledByDefault">False</BooleanProperty>
+    </GlobalSettings>
+    </Settings>
+  </SourceFileList>
+</StyleCopSettings>
diff --git a/src/csharp/Grpc.IntegrationTesting.Client/Grpc.IntegrationTesting.Client.csproj b/src/csharp/Grpc.IntegrationTesting.Client/Grpc.IntegrationTesting.Client.csproj
index 328acb5b47..dc1d0a44c0 100644
--- a/src/csharp/Grpc.IntegrationTesting.Client/Grpc.IntegrationTesting.Client.csproj
+++ b/src/csharp/Grpc.IntegrationTesting.Client/Grpc.IntegrationTesting.Client.csproj
@@ -3,8 +3,6 @@
   <PropertyGroup>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
     <Platform Condition=" '$(Platform)' == '' ">x86</Platform>
-    <ProductVersion>10.0.0</ProductVersion>
-    <SchemaVersion>2.0</SchemaVersion>
     <ProjectGuid>{3D166931-BA2D-416E-95A3-D36E8F6E90B9}</ProjectGuid>
     <OutputType>Exe</OutputType>
     <RootNamespace>Grpc.IntegrationTesting.Client</RootNamespace>
@@ -48,6 +46,10 @@
       <Project>{C61154BA-DD4A-4838-8420-0162A28925E0}</Project>
       <Name>Grpc.IntegrationTesting</Name>
     </ProjectReference>
+    <ProjectReference Include="..\Grpc.Core\Grpc.Core.csproj">
+      <Project>{CCC4440E-49F7-4790-B0AF-FEABB0837AE7}</Project>
+      <Name>Grpc.Core</Name>
+    </ProjectReference>
   </ItemGroup>
   <ItemGroup>
     <None Include="app.config" />
diff --git a/src/csharp/Grpc.IntegrationTesting.Server/Grpc.IntegrationTesting.Server.csproj b/src/csharp/Grpc.IntegrationTesting.Server/Grpc.IntegrationTesting.Server.csproj
index ae184c1dc7..f03c8f3ce3 100644
--- a/src/csharp/Grpc.IntegrationTesting.Server/Grpc.IntegrationTesting.Server.csproj
+++ b/src/csharp/Grpc.IntegrationTesting.Server/Grpc.IntegrationTesting.Server.csproj
@@ -3,8 +3,6 @@
   <PropertyGroup>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
     <Platform Condition=" '$(Platform)' == '' ">x86</Platform>
-    <ProductVersion>10.0.0</ProductVersion>
-    <SchemaVersion>2.0</SchemaVersion>
     <ProjectGuid>{A654F3B8-E859-4E6A-B30D-227527DBEF0D}</ProjectGuid>
     <OutputType>Exe</OutputType>
     <RootNamespace>Grpc.IntegrationTesting.Server</RootNamespace>
@@ -48,6 +46,10 @@
       <Project>{C61154BA-DD4A-4838-8420-0162A28925E0}</Project>
       <Name>Grpc.IntegrationTesting</Name>
     </ProjectReference>
+    <ProjectReference Include="..\Grpc.Core\Grpc.Core.csproj">
+      <Project>{CCC4440E-49F7-4790-B0AF-FEABB0837AE7}</Project>
+      <Name>Grpc.Core</Name>
+    </ProjectReference>
   </ItemGroup>
   <ItemGroup>
     <None Include="app.config" />
diff --git a/src/csharp/Grpc.IntegrationTesting/Grpc.IntegrationTesting.csproj b/src/csharp/Grpc.IntegrationTesting/Grpc.IntegrationTesting.csproj
index af4a75a034..d3c69ab9eb 100644
--- a/src/csharp/Grpc.IntegrationTesting/Grpc.IntegrationTesting.csproj
+++ b/src/csharp/Grpc.IntegrationTesting/Grpc.IntegrationTesting.csproj
@@ -32,21 +32,34 @@
     <PlatformTarget>x86</PlatformTarget>
   </PropertyGroup>
   <ItemGroup>
-    <Reference Include="Google.Apis.Auth.PlatformServices">
+    <Reference Include="Google.Apis.Auth, Version=1.9.1.12395, Culture=neutral, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\packages\Google.Apis.Auth.1.9.1\lib\net40\Google.Apis.Auth.dll</HintPath>
+    </Reference>
+    <Reference Include="Google.Apis.Auth.PlatformServices, Version=1.9.1.12399, Culture=neutral, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
       <HintPath>..\packages\Google.Apis.Auth.1.9.1\lib\net40\Google.Apis.Auth.PlatformServices.dll</HintPath>
     </Reference>
-    <Reference Include="Google.Apis.Core">
+    <Reference Include="Google.Apis.Core, Version=1.9.1.12394, Culture=neutral, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
       <HintPath>..\packages\Google.Apis.Core.1.9.1\lib\portable-net40+sl50+win+wpa81+wp80\Google.Apis.Core.dll</HintPath>
     </Reference>
-    <Reference Include="Microsoft.Threading.Tasks">
+    <Reference Include="Microsoft.Threading.Tasks, Version=1.0.12.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
       <HintPath>..\packages\Microsoft.Bcl.Async.1.0.168\lib\net40\Microsoft.Threading.Tasks.dll</HintPath>
     </Reference>
-    <Reference Include="Microsoft.Threading.Tasks.Extensions">
+    <Reference Include="Microsoft.Threading.Tasks.Extensions, Version=1.0.12.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
       <HintPath>..\packages\Microsoft.Bcl.Async.1.0.168\lib\net40\Microsoft.Threading.Tasks.Extensions.dll</HintPath>
     </Reference>
-    <Reference Include="Microsoft.Threading.Tasks.Extensions.Desktop">
+    <Reference Include="Microsoft.Threading.Tasks.Extensions.Desktop, Version=1.0.168.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
       <HintPath>..\packages\Microsoft.Bcl.Async.1.0.168\lib\net40\Microsoft.Threading.Tasks.Extensions.Desktop.dll</HintPath>
     </Reference>
+    <Reference Include="Newtonsoft.Json, Version=6.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
+      <HintPath>..\packages\Newtonsoft.Json.6.0.6\lib\net45\Newtonsoft.Json.dll</HintPath>
+    </Reference>
     <Reference Include="nunit.framework">
       <HintPath>..\packages\NUnit.2.6.4\lib\nunit.framework.dll</HintPath>
     </Reference>
@@ -63,16 +76,15 @@
     </Reference>
     <Reference Include="System.Net" />
     <Reference Include="System.Net.Http" />
-    <Reference Include="System.Net.Http.Extensions">
+    <Reference Include="System.Net.Http.Extensions, Version=2.2.28.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
       <HintPath>..\packages\Microsoft.Net.Http.2.2.28\lib\net45\System.Net.Http.Extensions.dll</HintPath>
     </Reference>
-    <Reference Include="System.Net.Http.Primitives">
+    <Reference Include="System.Net.Http.Primitives, Version=4.2.28.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
+      <SpecificVersion>False</SpecificVersion>
       <HintPath>..\packages\Microsoft.Net.Http.2.2.28\lib\net45\System.Net.Http.Primitives.dll</HintPath>
     </Reference>
     <Reference Include="System.Net.Http.WebRequest" />
-    <Reference Include="Newtonsoft.Json">
-      <HintPath>..\packages\Newtonsoft.Json.6.0.6\lib\net45\Newtonsoft.Json.dll</HintPath>
-    </Reference>
   </ItemGroup>
   <ItemGroup>
     <Compile Include="..\Grpc.Core\Version.cs">
diff --git a/src/csharp/Grpc.IntegrationTesting/InteropClient.cs b/src/csharp/Grpc.IntegrationTesting/InteropClient.cs
index 05e732dbd4..ce255f9423 100644
--- a/src/csharp/Grpc.IntegrationTesting/InteropClient.cs
+++ b/src/csharp/Grpc.IntegrationTesting/InteropClient.cs
@@ -135,7 +135,7 @@ namespace Grpc.IntegrationTesting
             GrpcEnvironment.Shutdown();
         }
 
-        private void RunTestCase(string testCase, TestService.ITestServiceClient client)
+        private void RunTestCase(string testCase, TestService.TestServiceClient client)
         {
             switch (testCase)
             {
@@ -163,6 +163,12 @@ namespace Grpc.IntegrationTesting
                 case "compute_engine_creds":
                     RunComputeEngineCreds(client);
                     break;
+                case "oauth2_auth_token":
+                    RunOAuth2AuthToken(client);
+                    break;
+                case "per_rpc_creds":
+                    RunPerRpcCreds(client);
+                    break;
                 case "cancel_after_begin":
                     RunCancelAfterBegin(client);
                     break;
@@ -213,7 +219,7 @@ namespace Grpc.IntegrationTesting
                 {
                     await call.RequestStream.WriteAll(bodySizes);
 
-                    var response = await call.Result;
+                    var response = await call.ResponseAsync;
                     Assert.AreEqual(74922, response.AggregatedPayloadSize);
                 }
                 Console.WriteLine("Passed!");
@@ -355,6 +361,51 @@ namespace Grpc.IntegrationTesting
             Console.WriteLine("Passed!");
         }
 
+        public static void RunOAuth2AuthToken(TestService.TestServiceClient client)
+        {
+            Console.WriteLine("running oauth2_auth_token");
+            var credential = GoogleCredential.GetApplicationDefault().CreateScoped(new[] { AuthScope });
+            Assert.IsTrue(credential.RequestAccessTokenAsync(CancellationToken.None).Result);
+            string oauth2Token = credential.Token.AccessToken;
+
+            // Intercept calls with an OAuth2 token obtained out-of-band.
+            client.HeaderInterceptor = new MetadataInterceptorDelegate((metadata) =>
+            {
+                metadata.Add(new Metadata.Entry("Authorization", "Bearer " + oauth2Token));
+            });
+
+            var request = SimpleRequest.CreateBuilder()
+                .SetFillUsername(true)
+                .SetFillOauthScope(true)
+                .Build();
+
+            var response = client.UnaryCall(request);
+
+            Assert.AreEqual(AuthScopeResponse, response.OauthScope);
+            Assert.AreEqual(ServiceAccountUser, response.Username);
+            Console.WriteLine("Passed!");
+        }
+
+        public static void RunPerRpcCreds(TestService.TestServiceClient client)
+        {
+            Console.WriteLine("running per_rpc_creds");
+
+            var credential = GoogleCredential.GetApplicationDefault().CreateScoped(new[] { AuthScope });
+            Assert.IsTrue(credential.RequestAccessTokenAsync(CancellationToken.None).Result);
+            string oauth2Token = credential.Token.AccessToken;
+
+            var request = SimpleRequest.CreateBuilder()
+                .SetFillUsername(true)
+                .SetFillOauthScope(true)
+                .Build();
+
+            var response = client.UnaryCall(request, headers: new Metadata { new Metadata.Entry("Authorization", "Bearer " + oauth2Token) });
+
+            Assert.AreEqual(AuthScopeResponse, response.OauthScope);
+            Assert.AreEqual(ServiceAccountUser, response.Username);
+            Console.WriteLine("Passed!");
+        }
+
         public static void RunCancelAfterBegin(TestService.ITestServiceClient client)
         {
             Task.Run(async () =>
@@ -370,7 +421,7 @@ namespace Grpc.IntegrationTesting
 
                     try
                     {
-                        var response = await call.Result;
+                        var response = await call.ResponseAsync;
                         Assert.Fail();
                     }
                     catch (RpcException e)
diff --git a/src/csharp/Grpc.IntegrationTesting/TestGrpc.cs b/src/csharp/Grpc.IntegrationTesting/TestGrpc.cs
index 96d9b23717..de2fa07441 100644
--- a/src/csharp/Grpc.IntegrationTesting/TestGrpc.cs
+++ b/src/csharp/Grpc.IntegrationTesting/TestGrpc.cs
@@ -60,9 +60,9 @@ namespace grpc.testing {
     public interface ITestServiceClient
     {
       global::grpc.testing.Empty EmptyCall(global::grpc.testing.Empty request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
-      Task<global::grpc.testing.Empty> EmptyCallAsync(global::grpc.testing.Empty request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
+      AsyncUnaryCall<global::grpc.testing.Empty> EmptyCallAsync(global::grpc.testing.Empty request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
       global::grpc.testing.SimpleResponse UnaryCall(global::grpc.testing.SimpleRequest request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
-      Task<global::grpc.testing.SimpleResponse> UnaryCallAsync(global::grpc.testing.SimpleRequest request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
+      AsyncUnaryCall<global::grpc.testing.SimpleResponse> UnaryCallAsync(global::grpc.testing.SimpleRequest request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
       AsyncServerStreamingCall<global::grpc.testing.StreamingOutputCallResponse> StreamingOutputCall(global::grpc.testing.StreamingOutputCallRequest request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
       AsyncClientStreamingCall<global::grpc.testing.StreamingInputCallRequest, global::grpc.testing.StreamingInputCallResponse> StreamingInputCall(Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
       AsyncDuplexStreamingCall<global::grpc.testing.StreamingOutputCallRequest, global::grpc.testing.StreamingOutputCallResponse> FullDuplexCall(Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken));
@@ -72,12 +72,12 @@ namespace grpc.testing {
     // server-side interface
     public interface ITestService
     {
-      Task<global::grpc.testing.Empty> EmptyCall(ServerCallContext context, global::grpc.testing.Empty request);
-      Task<global::grpc.testing.SimpleResponse> UnaryCall(ServerCallContext context, global::grpc.testing.SimpleRequest request);
-      Task StreamingOutputCall(ServerCallContext context, global::grpc.testing.StreamingOutputCallRequest request, IServerStreamWriter<global::grpc.testing.StreamingOutputCallResponse> responseStream);
-      Task<global::grpc.testing.StreamingInputCallResponse> StreamingInputCall(ServerCallContext context, IAsyncStreamReader<global::grpc.testing.StreamingInputCallRequest> requestStream);
-      Task FullDuplexCall(ServerCallContext context, IAsyncStreamReader<global::grpc.testing.StreamingOutputCallRequest> requestStream, IServerStreamWriter<global::grpc.testing.StreamingOutputCallResponse> responseStream);
-      Task HalfDuplexCall(ServerCallContext context, IAsyncStreamReader<global::grpc.testing.StreamingOutputCallRequest> requestStream, IServerStreamWriter<global::grpc.testing.StreamingOutputCallResponse> responseStream);
+      Task<global::grpc.testing.Empty> EmptyCall(global::grpc.testing.Empty request, ServerCallContext context);
+      Task<global::grpc.testing.SimpleResponse> UnaryCall(global::grpc.testing.SimpleRequest request, ServerCallContext context);
+      Task StreamingOutputCall(global::grpc.testing.StreamingOutputCallRequest request, IServerStreamWriter<global::grpc.testing.StreamingOutputCallResponse> responseStream, ServerCallContext context);
+      Task<global::grpc.testing.StreamingInputCallResponse> StreamingInputCall(IAsyncStreamReader<global::grpc.testing.StreamingInputCallRequest> requestStream, ServerCallContext context);
+      Task FullDuplexCall(IAsyncStreamReader<global::grpc.testing.StreamingOutputCallRequest> requestStream, IServerStreamWriter<global::grpc.testing.StreamingOutputCallResponse> responseStream, ServerCallContext context);
+      Task HalfDuplexCall(IAsyncStreamReader<global::grpc.testing.StreamingOutputCallRequest> requestStream, IServerStreamWriter<global::grpc.testing.StreamingOutputCallResponse> responseStream, ServerCallContext context);
     }
 
     // client stub
@@ -91,7 +91,7 @@ namespace grpc.testing {
         var call = CreateCall(__ServiceName, __Method_EmptyCall, headers);
         return Calls.BlockingUnaryCall(call, request, cancellationToken);
       }
-      public Task<global::grpc.testing.Empty> EmptyCallAsync(global::grpc.testing.Empty request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken))
+      public AsyncUnaryCall<global::grpc.testing.Empty> EmptyCallAsync(global::grpc.testing.Empty request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken))
       {
         var call = CreateCall(__ServiceName, __Method_EmptyCall, headers);
         return Calls.AsyncUnaryCall(call, request, cancellationToken);
@@ -101,7 +101,7 @@ namespace grpc.testing {
         var call = CreateCall(__ServiceName, __Method_UnaryCall, headers);
         return Calls.BlockingUnaryCall(call, request, cancellationToken);
       }
-      public Task<global::grpc.testing.SimpleResponse> UnaryCallAsync(global::grpc.testing.SimpleRequest request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken))
+      public AsyncUnaryCall<global::grpc.testing.SimpleResponse> UnaryCallAsync(global::grpc.testing.SimpleRequest request, Metadata headers = null, CancellationToken cancellationToken = default(CancellationToken))
       {
         var call = CreateCall(__ServiceName, __Method_UnaryCall, headers);
         return Calls.AsyncUnaryCall(call, request, cancellationToken);
diff --git a/src/csharp/Grpc.IntegrationTesting/TestServiceImpl.cs b/src/csharp/Grpc.IntegrationTesting/TestServiceImpl.cs
index 6bd997d1f4..ccf9fe6ced 100644
--- a/src/csharp/Grpc.IntegrationTesting/TestServiceImpl.cs
+++ b/src/csharp/Grpc.IntegrationTesting/TestServiceImpl.cs
@@ -46,19 +46,19 @@ namespace grpc.testing
     /// </summary>
     public class TestServiceImpl : TestService.ITestService
     {
-        public Task<Empty> EmptyCall(ServerCallContext context, Empty request)
+        public Task<Empty> EmptyCall(Empty request, ServerCallContext context)
         {
             return Task.FromResult(Empty.DefaultInstance);
         }
 
-        public Task<SimpleResponse> UnaryCall(ServerCallContext context, SimpleRequest request)
+        public Task<SimpleResponse> UnaryCall(SimpleRequest request, ServerCallContext context)
         {
             var response = SimpleResponse.CreateBuilder()
                 .SetPayload(CreateZerosPayload(request.ResponseSize)).Build();
             return Task.FromResult(response);
         }
 
-        public async Task StreamingOutputCall(ServerCallContext context, StreamingOutputCallRequest request, IServerStreamWriter<StreamingOutputCallResponse> responseStream)
+        public async Task StreamingOutputCall(StreamingOutputCallRequest request, IServerStreamWriter<StreamingOutputCallResponse> responseStream, ServerCallContext context)
         {
             foreach (var responseParam in request.ResponseParametersList)
             {
@@ -68,7 +68,7 @@ namespace grpc.testing
             }
         }
 
-        public async Task<StreamingInputCallResponse> StreamingInputCall(ServerCallContext context, IAsyncStreamReader<StreamingInputCallRequest> requestStream)
+        public async Task<StreamingInputCallResponse> StreamingInputCall(IAsyncStreamReader<StreamingInputCallRequest> requestStream, ServerCallContext context)
         {
             int sum = 0;
             await requestStream.ForEach(async request =>
@@ -78,7 +78,7 @@ namespace grpc.testing
             return StreamingInputCallResponse.CreateBuilder().SetAggregatedPayloadSize(sum).Build();
         }
 
-        public async Task FullDuplexCall(ServerCallContext context, IAsyncStreamReader<StreamingOutputCallRequest> requestStream, IServerStreamWriter<StreamingOutputCallResponse> responseStream)
+        public async Task FullDuplexCall(IAsyncStreamReader<StreamingOutputCallRequest> requestStream, IServerStreamWriter<StreamingOutputCallResponse> responseStream, ServerCallContext context)
         {
             await requestStream.ForEach(async request =>
             {
@@ -91,7 +91,7 @@ namespace grpc.testing
             });
         }
 
-        public async Task HalfDuplexCall(ServerCallContext context, IAsyncStreamReader<StreamingOutputCallRequest> requestStream, IServerStreamWriter<StreamingOutputCallResponse> responseStream)
+        public async Task HalfDuplexCall(IAsyncStreamReader<StreamingOutputCallRequest> requestStream, IServerStreamWriter<StreamingOutputCallResponse> responseStream, ServerCallContext context)
         {
             throw new NotImplementedException();
         }
diff --git a/src/csharp/ext/grpc_csharp_ext.c b/src/csharp/ext/grpc_csharp_ext.c
index 7dd1959a5f..682521446f 100644
--- a/src/csharp/ext/grpc_csharp_ext.c
+++ b/src/csharp/ext/grpc_csharp_ext.c
@@ -167,6 +167,29 @@ grpcsharp_metadata_array_add(grpc_metadata_array *array, const char *key,
   array->count++;
 }
 
+GPR_EXPORT gpr_intptr GPR_CALLTYPE
+grpcsharp_metadata_array_count(grpc_metadata_array *array) {
+  return (gpr_intptr) array->count;
+}
+
+GPR_EXPORT const char *GPR_CALLTYPE
+grpcsharp_metadata_array_get_key(grpc_metadata_array *array, size_t index) {
+  GPR_ASSERT(index < array->count);
+  return array->metadata[index].key;
+}
+
+GPR_EXPORT const char *GPR_CALLTYPE
+grpcsharp_metadata_array_get_value(grpc_metadata_array *array, size_t index) {
+  GPR_ASSERT(index < array->count);
+  return array->metadata[index].value;
+}
+
+GPR_EXPORT gpr_intptr GPR_CALLTYPE
+grpcsharp_metadata_array_get_value_length(grpc_metadata_array *array, size_t index) {
+  GPR_ASSERT(index < array->count);
+  return (gpr_intptr) array->metadata[index].value_length;
+}
+
 /* Move contents of metadata array */
 void grpcsharp_metadata_array_move(grpc_metadata_array *dest,
                                    grpc_metadata_array *src) {
@@ -218,6 +241,12 @@ GPR_EXPORT void GPR_CALLTYPE grpcsharp_batch_context_destroy(grpcsharp_batch_con
   gpr_free(ctx);
 }
 
+GPR_EXPORT const grpc_metadata_array *GPR_CALLTYPE
+grpcsharp_batch_context_recv_initial_metadata(
+    const grpcsharp_batch_context *ctx) {
+  return &(ctx->recv_initial_metadata);
+}
+
 GPR_EXPORT gpr_intptr GPR_CALLTYPE grpcsharp_batch_context_recv_message_length(
     const grpcsharp_batch_context *ctx) {
   if (!ctx->recv_message) {
@@ -260,6 +289,12 @@ grpcsharp_batch_context_recv_status_on_client_details(
   return ctx->recv_status_on_client.status_details;
 }
 
+GPR_EXPORT const grpc_metadata_array *GPR_CALLTYPE
+grpcsharp_batch_context_recv_status_on_client_trailing_metadata(
+    const grpcsharp_batch_context *ctx) {
+  return &(ctx->recv_status_on_client.trailing_metadata);
+}
+
 GPR_EXPORT grpc_call *GPR_CALLTYPE grpcsharp_batch_context_server_rpc_new_call(
     const grpcsharp_batch_context *ctx) {
   return ctx->server_rpc_new.call;
@@ -271,6 +306,24 @@ grpcsharp_batch_context_server_rpc_new_method(
   return ctx->server_rpc_new.call_details.method;
 }
 
+GPR_EXPORT const char *GPR_CALLTYPE
+grpcsharp_batch_context_server_rpc_new_host(
+    const grpcsharp_batch_context *ctx) {
+  return ctx->server_rpc_new.call_details.host;
+}
+
+GPR_EXPORT gpr_timespec GPR_CALLTYPE
+grpcsharp_batch_context_server_rpc_new_deadline(
+    const grpcsharp_batch_context *ctx) {
+  return ctx->server_rpc_new.call_details.deadline;
+}
+
+GPR_EXPORT const grpc_metadata_array *GPR_CALLTYPE
+grpcsharp_batch_context_server_rpc_new_request_metadata(
+    const grpcsharp_batch_context *ctx) {
+  return &(ctx->server_rpc_new.request_metadata);
+}
+
 GPR_EXPORT gpr_int32 GPR_CALLTYPE
 grpcsharp_batch_context_recv_close_on_server_cancelled(
     const grpcsharp_batch_context *ctx) {
@@ -589,15 +642,20 @@ GPR_EXPORT grpc_call_error GPR_CALLTYPE
 grpcsharp_call_send_status_from_server(grpc_call *call,
                                        grpcsharp_batch_context *ctx,
                                        grpc_status_code status_code,
-                                       const char *status_details) {
+                                       const char *status_details,
+                                       grpc_metadata_array *trailing_metadata) {
   /* TODO: don't use magic number */
   grpc_op ops[1];
   ops[0].op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   ops[0].data.send_status_from_server.status = status_code;
   ops[0].data.send_status_from_server.status_details =
       gpr_strdup(status_details);
-  ops[0].data.send_status_from_server.trailing_metadata = NULL;
-  ops[0].data.send_status_from_server.trailing_metadata_count = 0;
+  grpcsharp_metadata_array_move(&(ctx->send_status_from_server.trailing_metadata),
+                                  trailing_metadata);
+  ops[0].data.send_status_from_server.trailing_metadata_count =
+      ctx->send_status_from_server.trailing_metadata.count;
+  ops[0].data.send_status_from_server.trailing_metadata =
+      ctx->send_status_from_server.trailing_metadata.metadata;
   ops[0].flags = 0;
 
   return grpc_call_start_batch(call, ops, sizeof(ops) / sizeof(ops[0]), ctx);
diff --git a/src/node/README.md b/src/node/README.md
index 2f4c49096d..78781dab14 100644
--- a/src/node/README.md
+++ b/src/node/README.md
@@ -54,10 +54,10 @@ function loadObject(reflectionObject)
 Returns the same structure that `load` returns, but takes a reflection object from `ProtoBuf.js` instead of a file name.
 
 ```javascript
-function buildServer(serviceArray)
+function Server([serverOpions])
 ```
 
-Takes an array of service objects and returns a constructor for a server that handles requests to all of those services.
+Constructs a server to which service/implementation pairs can be added.
 
 
 ```javascript
diff --git a/src/node/examples/math_server.js b/src/node/examples/math_server.js
index 0a86e7eaff..b1f8a6323f 100644
--- a/src/node/examples/math_server.js
+++ b/src/node/examples/math_server.js
@@ -36,8 +36,6 @@
 var grpc = require('..');
 var math = grpc.load(__dirname + '/math.proto').math;
 
-var Server = grpc.buildServer([math.Math.service]);
-
 /**
  * Server function for division. Provides the /Math/DivMany and /Math/Div
  * functions (Div is just DivMany with only one stream element). For each
@@ -108,19 +106,17 @@ function mathDivMany(stream) {
     stream.end();
   });
 }
-
-var server = new Server({
-  'math.Math' : {
-    div: mathDiv,
-    fib: mathFib,
-    sum: mathSum,
-    divMany: mathDivMany
-  }
+var server = new grpc.Server();
+server.addProtoService(math.Math.service, {
+  div: mathDiv,
+  fib: mathFib,
+  sum: mathSum,
+  divMany: mathDivMany
 });
 
 if (require.main === module) {
   server.bind('0.0.0.0:50051');
-  server.listen();
+  server.start();
 }
 
 /**
diff --git a/src/node/examples/route_guide_server.js b/src/node/examples/route_guide_server.js
index c777eab7bc..70044a322c 100644
--- a/src/node/examples/route_guide_server.js
+++ b/src/node/examples/route_guide_server.js
@@ -40,8 +40,6 @@ var _ = require('lodash');
 var grpc = require('..');
 var examples = grpc.load(__dirname + '/route_guide.proto').examples;
 
-var Server = grpc.buildServer([examples.RouteGuide.service]);
-
 var COORD_FACTOR = 1e7;
 
 /**
@@ -228,14 +226,14 @@ function routeChat(call) {
  * @return {Server} The new server object
  */
 function getServer() {
-  return new Server({
-    'examples.RouteGuide' : {
-      getFeature: getFeature,
-      listFeatures: listFeatures,
-      recordRoute: recordRoute,
-      routeChat: routeChat
-    }
+  var server = new grpc.Server();
+  server.addProtoService(examples.RouteGuide.service, {
+    getFeature: getFeature,
+    listFeatures: listFeatures,
+    recordRoute: recordRoute,
+    routeChat: routeChat
   });
+  return server;
 }
 
 if (require.main === module) {
diff --git a/src/node/examples/stock_server.js b/src/node/examples/stock_server.js
index caaf9f99ba..f2eb6ad4ab 100644
--- a/src/node/examples/stock_server.js
+++ b/src/node/examples/stock_server.js
@@ -37,8 +37,6 @@ var _ = require('lodash');
 var grpc = require('..');
 var examples = grpc.load(__dirname + '/stock.proto').examples;
 
-var StockServer = grpc.buildServer([examples.Stock.service]);
-
 function getLastTradePrice(call, callback) {
   callback(null, {symbol: call.request.symbol, price: 88});
 }
@@ -73,13 +71,12 @@ function getLastTradePriceMultiple(call) {
   });
 }
 
-var stockServer = new StockServer({
-  'examples.Stock' : {
-    getLastTradePrice: getLastTradePrice,
-    getLastTradePriceMultiple: getLastTradePriceMultiple,
-    watchFutureTrades: watchFutureTrades,
-    getHighestTradePrice: getHighestTradePrice
-  }
+var stockServer = new grpc.Server();
+stockServer.addProtoService(examples.Stock.service, {
+  getLastTradePrice: getLastTradePrice,
+  getLastTradePriceMultiple: getLastTradePriceMultiple,
+  watchFutureTrades: watchFutureTrades,
+  getHighestTradePrice: getHighestTradePrice
 });
 
 if (require.main === module) {
diff --git a/src/node/index.js b/src/node/index.js
index b6a4e2d0ee..d81e780443 100644
--- a/src/node/index.js
+++ b/src/node/index.js
@@ -133,9 +133,9 @@ exports.loadObject = loadObject;
 exports.load = load;
 
 /**
- * See docs for server.makeServerConstructor
+ * See docs for Server
  */
-exports.buildServer = server.makeProtobufServerConstructor;
+exports.Server = server.Server;
 
 /**
  * Status name to code number mapping
@@ -159,5 +159,3 @@ exports.ServerCredentials = grpc.ServerCredentials;
 exports.getGoogleAuthDelegate = getGoogleAuthDelegate;
 
 exports.makeGenericClientConstructor = client.makeClientConstructor;
-
-exports.makeGenericServerConstructor = server.makeServerConstructor;
diff --git a/src/node/interop/interop_client.js b/src/node/interop/interop_client.js
index b61b0b63c0..e810e68e45 100644
--- a/src/node/interop/interop_client.js
+++ b/src/node/interop/interop_client.js
@@ -318,6 +318,51 @@ function authTest(expected_user, scope, client, done) {
   });
 }
 
+function oauth2Test(expected_user, scope, per_rpc, client, done) {
+  (new GoogleAuth()).getApplicationDefault(function(err, credential) {
+    assert.ifError(err);
+    var arg = {
+      fill_username: true,
+      fill_oauth_scope: true
+    };
+    credential = credential.createScoped(scope);
+    credential.getAccessToken(function(err, token) {
+      assert.ifError(err);
+      var updateMetadata = function(authURI, metadata, callback) {
+        metadata = _.clone(metadata);
+        if (metadata.Authorization) {
+          metadata.Authorization = _.clone(metadata.Authorization);
+        } else {
+          metadata.Authorization = [];
+        }
+        metadata.Authorization.push('Bearer ' + token);
+        callback(null, metadata);
+      };
+      var makeTestCall = function(error, client_metadata) {
+        assert.ifError(error);
+        var call = client.unaryCall(arg, function(err, resp) {
+          assert.ifError(err);
+          assert.strictEqual(resp.username, expected_user);
+          assert.strictEqual(resp.oauth_scope, AUTH_SCOPE_RESPONSE);
+        });
+        call.on('status', function(status) {
+          assert.strictEqual(status.code, grpc.status.OK);
+          if (done) {
+            done();
+          }
+        });
+      };
+      if (per_rpc) {
+        updateMetadata('', {}, makeTestCall);
+      } else {
+        client.updateMetadata = updateMetadata;
+        makeTestCall(null, {});
+      }
+
+    });
+  });
+}
+
 /**
  * Map from test case names to test functions
  */
@@ -333,7 +378,9 @@ var test_cases = {
   timeout_on_sleeping_server: timeoutOnSleepingServer,
   compute_engine_creds: _.partial(authTest, COMPUTE_ENGINE_USER, null),
   service_account_creds: _.partial(authTest, AUTH_USER, AUTH_SCOPE),
-  jwt_token_creds: _.partial(authTest, AUTH_USER, null)
+  jwt_token_creds: _.partial(authTest, AUTH_USER, null),
+  oauth2_auth_token: _.partial(oauth2Test, AUTH_USER, AUTH_SCOPE, false),
+  per_rpc_creds: _.partial(oauth2Test, AUTH_USER, AUTH_SCOPE, true)
 };
 
 /**
diff --git a/src/node/interop/interop_server.js b/src/node/interop/interop_server.js
index 0baa78a094..505c6bb537 100644
--- a/src/node/interop/interop_server.js
+++ b/src/node/interop/interop_server.js
@@ -38,7 +38,6 @@ var path = require('path');
 var _ = require('lodash');
 var grpc = require('..');
 var testProto = grpc.load(__dirname + '/test.proto').grpc.testing;
-var Server = grpc.buildServer([testProto.TestService.service]);
 
 /**
  * Create a buffer filled with size zeroes
@@ -173,16 +172,15 @@ function getServer(port, tls) {
                                                     key_data,
                                                     pem_data);
   }
-  var server = new Server({
-    'grpc.testing.TestService' : {
-      emptyCall: handleEmpty,
-      unaryCall: handleUnary,
-      streamingOutputCall: handleStreamingOutput,
-      streamingInputCall: handleStreamingInput,
-      fullDuplexCall: handleFullDuplex,
-      halfDuplexCall: handleHalfDuplex
-    }
-  }, null, options);
+  var server = new grpc.Server(options);
+  server.addProtoService(testProto.TestService.service, {
+    emptyCall: handleEmpty,
+    unaryCall: handleUnary,
+    streamingOutputCall: handleStreamingOutput,
+    streamingInputCall: handleStreamingInput,
+    fullDuplexCall: handleFullDuplex,
+    halfDuplexCall: handleHalfDuplex
+  });
   var port_num = server.bind('0.0.0.0:' + port, server_creds);
   return {server: server, port: port_num};
 }
diff --git a/src/node/src/client.js b/src/node/src/client.js
index b7bad949d4..da6327b432 100644
--- a/src/node/src/client.js
+++ b/src/node/src/client.js
@@ -47,6 +47,7 @@ var Readable = stream.Readable;
 var Writable = stream.Writable;
 var Duplex = stream.Duplex;
 var util = require('util');
+var version = require('../package.json').version;
 
 util.inherits(ClientWritableStream, Writable);
 
@@ -517,9 +518,12 @@ function makeClientConstructor(methods, serviceName) {
         callback(null, metadata);
       };
     }
-
-    this.server_address = address.replace(/\/$/, '');
+    if (!options) {
+      options = {};
+    }
+    options['grpc.primary_user_agent'] = 'grpc-node/' + version;
     this.channel = new grpc.Channel(address, options);
+    this.server_address = address.replace(/\/$/, '');
     this.auth_uri = this.server_address + '/' + serviceName;
     this.updateMetadata = updateMetadata;
   }
diff --git a/src/node/src/server.js b/src/node/src/server.js
index 00be400e61..0a3a0031bd 100644
--- a/src/node/src/server.js
+++ b/src/node/src/server.js
@@ -72,6 +72,9 @@ function handleError(call, error) {
     status.metadata = error.metadata;
   }
   var error_batch = {};
+  if (!call.metadataSent) {
+    error_batch[grpc.opType.SEND_INITIAL_METADATA] = {};
+  }
   error_batch[grpc.opType.SEND_STATUS_FROM_SERVER] = status;
   call.startBatch(error_batch, function(){});
 }
@@ -115,6 +118,10 @@ function sendUnaryResponse(call, value, serialize, metadata) {
   if (metadata) {
     status.metadata = metadata;
   }
+  if (!call.metadataSent) {
+    end_batch[grpc.opType.SEND_INITIAL_METADATA] = {};
+    call.metadataSent = true;
+  }
   end_batch[grpc.opType.SEND_MESSAGE] = serialize(value);
   end_batch[grpc.opType.SEND_STATUS_FROM_SERVER] = status;
   call.startBatch(end_batch, function (){});
@@ -136,6 +143,10 @@ function setUpWritable(stream, serialize) {
   stream.serialize = common.wrapIgnoreNull(serialize);
   function sendStatus() {
     var batch = {};
+    if (!stream.call.metadataSent) {
+      stream.call.metadataSent = true;
+      batch[grpc.opType.SEND_INITIAL_METADATA] = {};
+    }
     batch[grpc.opType.SEND_STATUS_FROM_SERVER] = stream.status;
     stream.call.startBatch(batch, function(){});
   }
@@ -239,6 +250,10 @@ function ServerWritableStream(call, serialize) {
 function _write(chunk, encoding, callback) {
   /* jshint validthis: true */
   var batch = {};
+  if (!this.call.metadataSent) {
+    batch[grpc.opType.SEND_INITIAL_METADATA] = {};
+    this.call.metadataSent = true;
+  }
   batch[grpc.opType.SEND_MESSAGE] = this.serialize(chunk);
   this.call.startBatch(batch, function(err, value) {
     if (err) {
@@ -251,6 +266,23 @@ function _write(chunk, encoding, callback) {
 
 ServerWritableStream.prototype._write = _write;
 
+function sendMetadata(responseMetadata) {
+  /* jshint validthis: true */
+  if (!this.call.metadataSent) {
+    this.call.metadataSent = true;
+    var batch = [];
+    batch[grpc.opType.SEND_INITIAL_METADATA] = responseMetadata;
+    this.call.startBatch(batch, function(err) {
+      if (err) {
+        this.emit('error', err);
+        return;
+      }
+    });
+  }
+}
+
+ServerWritableStream.prototype.sendMetadata = sendMetadata;
+
 util.inherits(ServerReadableStream, Readable);
 
 /**
@@ -339,6 +371,7 @@ function ServerDuplexStream(call, serialize, deserialize) {
 
 ServerDuplexStream.prototype._read = _read;
 ServerDuplexStream.prototype._write = _write;
+ServerDuplexStream.prototype.sendMetadata = sendMetadata;
 
 /**
  * Fully handle a unary call
@@ -348,12 +381,20 @@ ServerDuplexStream.prototype._write = _write;
  */
 function handleUnary(call, handler, metadata) {
   var emitter = new EventEmitter();
+  emitter.sendMetadata = function(responseMetadata) {
+    if (!call.metadataSent) {
+      call.metadataSent = true;
+      var batch = {};
+      batch[grpc.opType.SEND_INITIAL_METADATA] = responseMetadata;
+      call.startBatch(batch, function() {});
+    }
+  };
   emitter.on('error', function(error) {
     handleError(call, error);
   });
+  emitter.metadata = metadata;
   waitForCancel(call, emitter);
   var batch = {};
-  batch[grpc.opType.SEND_INITIAL_METADATA] = metadata;
   batch[grpc.opType.RECV_MESSAGE] = true;
   call.startBatch(batch, function(err, result) {
     if (err) {
@@ -392,8 +433,8 @@ function handleUnary(call, handler, metadata) {
 function handleServerStreaming(call, handler, metadata) {
   var stream = new ServerWritableStream(call, handler.serialize);
   waitForCancel(call, stream);
+  stream.metadata = metadata;
   var batch = {};
-  batch[grpc.opType.SEND_INITIAL_METADATA] = metadata;
   batch[grpc.opType.RECV_MESSAGE] = true;
   call.startBatch(batch, function(err, result) {
     if (err) {
@@ -419,13 +460,19 @@ function handleServerStreaming(call, handler, metadata) {
  */
 function handleClientStreaming(call, handler, metadata) {
   var stream = new ServerReadableStream(call, handler.deserialize);
+  stream.sendMetadata = function(responseMetadata) {
+    if (!call.metadataSent) {
+      call.metadataSent = true;
+      var batch = {};
+      batch[grpc.opType.SEND_INITIAL_METADATA] = responseMetadata;
+      call.startBatch(batch, function() {});
+    }
+  };
   stream.on('error', function(error) {
     handleError(call, error);
   });
   waitForCancel(call, stream);
-  var metadata_batch = {};
-  metadata_batch[grpc.opType.SEND_INITIAL_METADATA] = metadata;
-  call.startBatch(metadata_batch, function() {});
+  stream.metadata = metadata;
   handler.func(stream, function(err, value, trailer) {
     stream.terminate();
     if (err) {
@@ -449,9 +496,7 @@ function handleBidiStreaming(call, handler, metadata) {
   var stream = new ServerDuplexStream(call, handler.serialize,
                                       handler.deserialize);
   waitForCancel(call, stream);
-  var metadata_batch = {};
-  metadata_batch[grpc.opType.SEND_INITIAL_METADATA] = metadata;
-  call.startBatch(metadata_batch, function() {});
+  stream.metadata = metadata;
   handler.func(stream);
 }
 
@@ -466,29 +511,28 @@ var streamHandlers = {
  * Constructs a server object that stores request handlers and delegates
  * incoming requests to those handlers
  * @constructor
- * @param {function(string, Object<string, Array<Buffer>>):
-           Object<string, Array<Buffer|string>>=} getMetadata Callback that gets
- *     metatada for a given method
  * @param {Object=} options Options that should be passed to the internal server
  *     implementation
  */
-function Server(getMetadata, options) {
+function Server(options) {
   this.handlers = {};
   var handlers = this.handlers;
   var server = new grpc.Server(options);
   this._server = server;
+  this.started = false;
   /**
    * Start the server and begin handling requests
    * @this Server
    */
-  this.listen = function() {
+  this.start = function() {
+    if (this.started) {
+      throw new Error('Server is already running');
+    }
+    this.started = true;
     console.log('Server starting');
     _.each(handlers, function(handler, handler_name) {
       console.log('Serving', handler_name);
     });
-    if (this.started) {
-      throw 'Server is already running';
-    }
     server.start();
     /**
      * Handles the SERVER_RPC_NEW event. If there is a handler associated with
@@ -523,11 +567,7 @@ function Server(getMetadata, options) {
         call.startBatch(batch, function() {});
         return;
       }
-      var response_metadata = {};
-      if (getMetadata) {
-        response_metadata = getMetadata(method, metadata);
-      }
-      streamHandlers[handler.type](call, handler, response_metadata);
+      streamHandlers[handler.type](call, handler, metadata);
     }
     server.requestCall(handleNewCall);
   };
@@ -565,6 +605,47 @@ Server.prototype.register = function(name, handler, serialize, deserialize,
   return true;
 };
 
+Server.prototype.addService = function(service, implementation) {
+  if (this.started) {
+    throw new Error('Can\'t add a service to a started server.');
+  }
+  var self = this;
+  _.each(service, function(attrs, name) {
+    var method_type;
+    if (attrs.requestStream) {
+      if (attrs.responseStream) {
+        method_type = 'bidi';
+      } else {
+        method_type = 'client_stream';
+      }
+    } else {
+      if (attrs.responseStream) {
+        method_type = 'server_stream';
+      } else {
+        method_type = 'unary';
+      }
+    }
+    if (implementation[name] === undefined) {
+      throw new Error('Method handler for ' + attrs.path +
+          ' not provided.');
+    }
+    var serialize = attrs.responseSerialize;
+    var deserialize = attrs.requestDeserialize;
+    var register_success = self.register(attrs.path,
+                                         _.bind(implementation[name],
+                                                implementation),
+                                         serialize, deserialize, method_type);
+    if (!register_success) {
+      throw new Error('Method handler for ' + attrs.path +
+          ' already provided.');
+    }
+  });
+};
+
+Server.prototype.addProtoService = function(service, implementation) {
+  this.addService(common.getProtobufServiceAttrs(service), implementation);
+};
+
 /**
  * Binds the server to the given port, with SSL enabled if creds is given
  * @param {string} port The port that the server should bind on, in the format
@@ -573,6 +654,9 @@ Server.prototype.register = function(name, handler, serialize, deserialize,
  *     nothing for an insecure port
  */
 Server.prototype.bind = function(port, creds) {
+  if (this.started) {
+    throw new Error('Can\'t bind an already running server to an address');
+  }
   if (creds) {
     return this._server.addSecureHttp2Port(port, creds);
   } else {
@@ -581,131 +665,6 @@ Server.prototype.bind = function(port, creds) {
 };
 
 /**
- * Create a constructor for servers with services defined by service_attr_map.
- * That is an object that maps (namespaced) service names to objects that in
- * turn map method names to objects with the following keys:
- * path: The path on the server for accessing the method. For example, for
- *     protocol buffers, we use "/service_name/method_name"
- * requestStream: bool indicating whether the client sends a stream
- * resonseStream: bool indicating whether the server sends a stream
- * requestDeserialize: function to deserialize request objects
- * responseSerialize: function to serialize response objects
- * @param {Object} service_attr_map An object mapping service names to method
- *     attribute map objects
- * @return {function(Object, function, Object=)} New server constructor
- */
-function makeServerConstructor(service_attr_map) {
-  /**
-   * Create a server with the given handlers for all of the methods.
-   * @constructor
-   * @param {Object} service_handlers Map from service names to map from method
-   *     names to handlers
-   * @param {function(string, Object<string, Array<Buffer>>):
-             Object<string, Array<Buffer|string>>=} getMetadata Callback that
-   *     gets metatada for a given method
-   * @param {Object=} options Options to pass to the underlying server
-   */
-  function SurfaceServer(service_handlers, getMetadata, options) {
-    var server = new Server(getMetadata, options);
-    this.inner_server = server;
-    _.each(service_attr_map, function(service_attrs, service_name) {
-      if (service_handlers[service_name] === undefined) {
-        throw new Error('Handlers for service ' +
-            service_name + ' not provided.');
-      }
-      _.each(service_attrs, function(attrs, name) {
-        var method_type;
-        if (attrs.requestStream) {
-          if (attrs.responseStream) {
-            method_type = 'bidi';
-          } else {
-            method_type = 'client_stream';
-          }
-        } else {
-          if (attrs.responseStream) {
-            method_type = 'server_stream';
-          } else {
-            method_type = 'unary';
-          }
-        }
-        if (service_handlers[service_name][name] === undefined) {
-          throw new Error('Method handler for ' + attrs.path +
-              ' not provided.');
-        }
-        var serialize = attrs.responseSerialize;
-        var deserialize = attrs.requestDeserialize;
-        server.register(attrs.path, _.bind(service_handlers[service_name][name],
-                                           service_handlers[service_name]),
-                        serialize, deserialize, method_type);
-      });
-    }, this);
-  }
-
-  /**
-   * Binds the server to the given port, with SSL enabled if creds is supplied
-   * @param {string} port The port that the server should bind on, in the format
-   *     "address:port"
-   * @param {boolean=} creds Credentials to use for SSL
-   * @return {SurfaceServer} this
-   */
-  SurfaceServer.prototype.bind = function(port, creds) {
-    return this.inner_server.bind(port, creds);
-  };
-
-  /**
-   * Starts the server listening on any bound ports
-   * @return {SurfaceServer} this
-   */
-  SurfaceServer.prototype.listen = function() {
-    this.inner_server.listen();
-    return this;
-  };
-
-  /**
-   * Shuts the server down; tells it to stop listening for new requests and to
-   * kill old requests.
-   */
-  SurfaceServer.prototype.shutdown = function() {
-    this.inner_server.shutdown();
-  };
-
-  return SurfaceServer;
-}
-
-/**
- * Create a constructor for servers that serve the given services.
- * @param {Array<ProtoBuf.Reflect.Service>} services The services that the
- *     servers will serve
- * @return {function(Object, function, Object=)} New server constructor
- */
-function makeProtobufServerConstructor(services) {
-  var qual_names = [];
-  var service_attr_map = {};
-  _.each(services, function(service) {
-    var service_name = common.fullyQualifiedName(service);
-    _.each(service.children, function(method) {
-      var name = common.fullyQualifiedName(method);
-      if (_.indexOf(qual_names, name) !== -1) {
-        throw new Error('Method ' + name + ' exposed by more than one service');
-      }
-      qual_names.push(name);
-    });
-    var method_attrs = common.getProtobufServiceAttrs(service);
-    if (!service_attr_map.hasOwnProperty(service_name)) {
-      service_attr_map[service_name] = {};
-    }
-    service_attr_map[service_name] = _.extend(service_attr_map[service_name],
-                                              method_attrs);
-  });
-  return makeServerConstructor(service_attr_map);
-}
-
-/**
- * See documentation for makeServerConstructor
- */
-exports.makeServerConstructor = makeServerConstructor;
-
-/**
- * See documentation for makeProtobufServerConstructor
+ * See documentation for Server
  */
-exports.makeProtobufServerConstructor = makeProtobufServerConstructor;
+exports.Server = Server;
diff --git a/src/node/test/health_test.js b/src/node/test/health_test.js
index 4d1a5082e0..bb700cc46c 100644
--- a/src/node/test/health_test.js
+++ b/src/node/test/health_test.js
@@ -49,14 +49,13 @@ describe('Health Checking', function() {
       'grpc.test.TestService': 'SERVING'
     }
   };
-  var HealthServer = grpc.buildServer([health.service]);
-  var healthServer = new HealthServer({
-    'grpc.health.v1alpha.Health': new health.Implementation(statusMap)
-  });
+  var healthServer = new grpc.Server();
+  healthServer.addProtoService(health.service,
+                               new health.Implementation(statusMap));
   var healthClient;
   before(function() {
     var port_num = healthServer.bind('0.0.0.0:0');
-    healthServer.listen();
+    healthServer.start();
     healthClient = new health.Client('localhost:' + port_num);
   });
   after(function() {
diff --git a/src/node/test/interop_sanity_test.js b/src/node/test/interop_sanity_test.js
index fcd8eb6403..0a5eb29c0c 100644
--- a/src/node/test/interop_sanity_test.js
+++ b/src/node/test/interop_sanity_test.js
@@ -46,7 +46,7 @@ describe('Interop tests', function() {
   before(function(done) {
     var server_obj = interop_server.getServer(0, true);
     server = server_obj.server;
-    server.listen();
+    server.start();
     port = 'localhost:' + server_obj.port;
     done();
   });
diff --git a/src/node/test/math_client_test.js b/src/node/test/math_client_test.js
index 3461922e66..f2751857ff 100644
--- a/src/node/test/math_client_test.js
+++ b/src/node/test/math_client_test.js
@@ -52,7 +52,7 @@ var server = require('../examples/math_server.js');
 describe('Math client', function() {
   before(function(done) {
     var port_num = server.bind('0.0.0.0:0');
-    server.listen();
+    server.start();
     math_client = new math.Math('localhost:' + port_num);
     done();
   });
diff --git a/src/node/test/surface_test.js b/src/node/test/surface_test.js
index 125957277f..3cb68f8cd8 100644
--- a/src/node/test/surface_test.js
+++ b/src/node/test/surface_test.js
@@ -69,34 +69,45 @@ describe('File loader', function() {
     });
   });
 });
-describe('Surface server constructor', function() {
-  it('Should fail with conflicting method names', function() {
-    assert.throws(function() {
-      grpc.buildServer([mathService, mathService]);
-    });
+describe('Server.prototype.addProtoService', function() {
+  var server;
+  var dummyImpls = {
+    'div': function() {},
+    'divMany': function() {},
+    'fib': function() {},
+    'sum': function() {}
+  };
+  beforeEach(function() {
+    server = new grpc.Server();
+  });
+  afterEach(function() {
+    server.shutdown();
   });
   it('Should succeed with a single service', function() {
     assert.doesNotThrow(function() {
-      grpc.buildServer([mathService]);
+      server.addProtoService(mathService, dummyImpls);
+    });
+  });
+  it('Should fail with conflicting method names', function() {
+    server.addProtoService(mathService, dummyImpls);
+    assert.throws(function() {
+      server.addProtoService(mathService, dummyImpls);
     });
   });
   it('Should fail with missing handlers', function() {
-    var Server = grpc.buildServer([mathService]);
     assert.throws(function() {
-      new Server({
-        'math.Math': {
-          'div': function() {},
-          'divMany': function() {},
-          'fib': function() {}
-        }
+      server.addProtoService(mathService, {
+        'div': function() {},
+        'divMany': function() {},
+        'fib': function() {}
       });
     }, /math.Math.Sum/);
   });
-  it('Should fail with no handlers for the service', function() {
-    var Server = grpc.buildServer([mathService]);
+  it('Should fail if the server has been started', function() {
+    server.start();
     assert.throws(function() {
-      new Server({});
-    }, /math.Math/);
+      server.addProtoService(mathService, dummyImpls);
+    });
   });
 });
 describe('Echo service', function() {
@@ -105,18 +116,16 @@ describe('Echo service', function() {
   before(function() {
     var test_proto = ProtoBuf.loadProtoFile(__dirname + '/echo_service.proto');
     var echo_service = test_proto.lookup('EchoService');
-    var Server = grpc.buildServer([echo_service]);
-    server = new Server({
-      'EchoService': {
-        echo: function(call, callback) {
-          callback(null, call.request);
-        }
+    server = new grpc.Server();
+    server.addProtoService(echo_service, {
+      echo: function(call, callback) {
+        callback(null, call.request);
       }
     });
     var port = server.bind('localhost:0');
     var Client = surface_client.makeProtobufClientConstructor(echo_service);
     client = new Client('localhost:' + port);
-    server.listen();
+    server.start();
   });
   after(function() {
     server.shutdown();
@@ -151,18 +160,14 @@ describe('Generic client and server', function() {
     var client;
     var server;
     before(function() {
-      var Server = grpc.makeGenericServerConstructor({
-        string: string_service_attrs
-      });
-      server = new Server({
-        string: {
-          capitalize: function(call, callback) {
-            callback(null, _.capitalize(call.request));
-          }
+      server = new grpc.Server();
+      server.addService(string_service_attrs, {
+        capitalize: function(call, callback) {
+          callback(null, _.capitalize(call.request));
         }
       });
       var port = server.bind('localhost:0');
-      server.listen();
+      server.start();
       var Client = grpc.makeGenericClientConstructor(string_service_attrs);
       client = new Client('localhost:' + port);
     });
@@ -178,6 +183,92 @@ describe('Generic client and server', function() {
     });
   });
 });
+describe('Echo metadata', function() {
+  var client;
+  var server;
+  before(function() {
+    var test_proto = ProtoBuf.loadProtoFile(__dirname + '/test_service.proto');
+    var test_service = test_proto.lookup('TestService');
+    server = new grpc.Server();
+    server.addProtoService(test_service, {
+      unary: function(call, cb) {
+        call.sendMetadata(call.metadata);
+        cb(null, {});
+      },
+      clientStream: function(stream, cb){
+        stream.on('data', function(data) {});
+        stream.on('end', function() {
+          stream.sendMetadata(stream.metadata);
+          cb(null, {});
+        });
+      },
+      serverStream: function(stream) {
+        stream.sendMetadata(stream.metadata);
+        stream.end();
+      },
+      bidiStream: function(stream) {
+        stream.on('data', function(data) {});
+        stream.on('end', function() {
+          stream.sendMetadata(stream.metadata);
+          stream.end();
+        });
+      }
+    });
+    var port = server.bind('localhost:0');
+    var Client = surface_client.makeProtobufClientConstructor(test_service);
+    client = new Client('localhost:' + port);
+    server.start();
+  });
+  after(function() {
+    server.shutdown();
+  });
+  it('with unary call', function(done) {
+    var call = client.unary({}, function(err, data) {
+      assert.ifError(err);
+    }, {key: ['value']});
+    call.on('metadata', function(metadata) {
+      assert.deepEqual(metadata.key, ['value']);
+      done();
+    });
+  });
+  it('with client stream call', function(done) {
+    var call = client.clientStream(function(err, data) {
+      assert.ifError(err);
+    }, {key: ['value']});
+    call.on('metadata', function(metadata) {
+      assert.deepEqual(metadata.key, ['value']);
+      done();
+    });
+    call.end();
+  });
+  it('with server stream call', function(done) {
+    var call = client.serverStream({}, {key: ['value']});
+    call.on('data', function() {});
+    call.on('metadata', function(metadata) {
+      assert.deepEqual(metadata.key, ['value']);
+      done();
+    });
+  });
+  it('with bidi stream call', function(done) {
+    var call = client.bidiStream({key: ['value']});
+    call.on('data', function() {});
+    call.on('metadata', function(metadata) {
+      assert.deepEqual(metadata.key, ['value']);
+      done();
+    });
+    call.end();
+  });
+  it('shows the correct user-agent string', function(done) {
+    var version = require('../package.json').version;
+    var call = client.unary({}, function(err, data) {
+      assert.ifError(err);
+    }, {key: ['value']});
+    call.on('metadata', function(metadata) {
+      assert(_.startsWith(metadata['user-agent'], 'grpc-node/' + version));
+      done();
+    });
+  });
+});
 describe('Other conditions', function() {
   var client;
   var server;
@@ -185,72 +276,70 @@ describe('Other conditions', function() {
   before(function() {
     var test_proto = ProtoBuf.loadProtoFile(__dirname + '/test_service.proto');
     var test_service = test_proto.lookup('TestService');
-    var Server = grpc.buildServer([test_service]);
-    server = new Server({
-      TestService: {
-        unary: function(call, cb) {
-          var req = call.request;
-          if (req.error) {
-            cb(new Error('Requested error'), null, {metadata: ['yes']});
+    server = new grpc.Server();
+    server.addProtoService(test_service, {
+      unary: function(call, cb) {
+        var req = call.request;
+        if (req.error) {
+          cb(new Error('Requested error'), null, {trailer_present: ['yes']});
+        } else {
+          cb(null, {count: 1}, {trailer_present: ['yes']});
+        }
+      },
+      clientStream: function(stream, cb){
+        var count = 0;
+        var errored;
+        stream.on('data', function(data) {
+          if (data.error) {
+            errored = true;
+            cb(new Error('Requested error'), null, {trailer_present: ['yes']});
           } else {
-            cb(null, {count: 1}, {metadata: ['yes']});
+            count += 1;
           }
-        },
-        clientStream: function(stream, cb){
-          var count = 0;
-          var errored;
-          stream.on('data', function(data) {
-            if (data.error) {
-              errored = true;
-              cb(new Error('Requested error'), null, {metadata: ['yes']});
-            } else {
-              count += 1;
-            }
-          });
-          stream.on('end', function() {
-            if (!errored) {
-              cb(null, {count: count}, {metadata: ['yes']});
-            }
-          });
-        },
-        serverStream: function(stream) {
-          var req = stream.request;
-          if (req.error) {
+        });
+        stream.on('end', function() {
+          if (!errored) {
+            cb(null, {count: count}, {trailer_present: ['yes']});
+          }
+        });
+      },
+      serverStream: function(stream) {
+        var req = stream.request;
+        if (req.error) {
+          var err = new Error('Requested error');
+          err.metadata = {trailer_present: ['yes']};
+          stream.emit('error', err);
+        } else {
+          for (var i = 0; i < 5; i++) {
+            stream.write({count: i});
+          }
+          stream.end({trailer_present: ['yes']});
+        }
+      },
+      bidiStream: function(stream) {
+        var count = 0;
+        stream.on('data', function(data) {
+          if (data.error) {
             var err = new Error('Requested error');
-            err.metadata = {metadata: ['yes']};
+            err.metadata = {
+              trailer_present: ['yes'],
+              count: ['' + count]
+            };
             stream.emit('error', err);
           } else {
-            for (var i = 0; i < 5; i++) {
-              stream.write({count: i});
-            }
-            stream.end({metadata: ['yes']});
+            stream.write({count: count});
+            count += 1;
           }
-        },
-        bidiStream: function(stream) {
-          var count = 0;
-          stream.on('data', function(data) {
-            if (data.error) {
-              var err = new Error('Requested error');
-              err.metadata = {
-                metadata: ['yes'],
-                count: ['' + count]
-              };
-              stream.emit('error', err);
-            } else {
-              stream.write({count: count});
-              count += 1;
-            }
-          });
-          stream.on('end', function() {
-            stream.end({metadata: ['yes']});
-          });
-        }
+        });
+        stream.on('end', function() {
+          stream.end({trailer_present: ['yes']});
+        });
       }
     });
     port = server.bind('localhost:0');
     var Client = surface_client.makeProtobufClientConstructor(test_service);
     client = new Client('localhost:' + port);
-    server.listen();
+    server.start();
   });
   after(function() {
     server.shutdown();
@@ -340,7 +429,7 @@ describe('Other conditions', function() {
         assert.ifError(err);
       });
       call.on('status', function(status) {
-        assert.deepEqual(status.metadata.metadata, ['yes']);
+        assert.deepEqual(status.metadata.trailer_present, ['yes']);
         done();
       });
     });
@@ -349,7 +438,7 @@ describe('Other conditions', function() {
         assert(err);
       });
       call.on('status', function(status) {
-        assert.deepEqual(status.metadata.metadata, ['yes']);
+        assert.deepEqual(status.metadata.trailer_present, ['yes']);
         done();
       });
     });
@@ -361,7 +450,7 @@ describe('Other conditions', function() {
       call.write({error: false});
       call.end();
       call.on('status', function(status) {
-        assert.deepEqual(status.metadata.metadata, ['yes']);
+        assert.deepEqual(status.metadata.trailer_present, ['yes']);
         done();
       });
     });
@@ -373,7 +462,7 @@ describe('Other conditions', function() {
       call.write({error: true});
       call.end();
       call.on('status', function(status) {
-        assert.deepEqual(status.metadata.metadata, ['yes']);
+        assert.deepEqual(status.metadata.trailer_present, ['yes']);
         done();
       });
     });
@@ -382,7 +471,7 @@ describe('Other conditions', function() {
       call.on('data', function(){});
       call.on('status', function(status) {
         assert.strictEqual(status.code, grpc.status.OK);
-        assert.deepEqual(status.metadata.metadata, ['yes']);
+        assert.deepEqual(status.metadata.trailer_present, ['yes']);
         done();
       });
     });
@@ -390,7 +479,7 @@ describe('Other conditions', function() {
       var call = client.serverStream({error: true});
       call.on('data', function(){});
       call.on('error', function(error) {
-        assert.deepEqual(error.metadata.metadata, ['yes']);
+        assert.deepEqual(error.metadata.trailer_present, ['yes']);
         done();
       });
     });
@@ -402,7 +491,7 @@ describe('Other conditions', function() {
       call.on('data', function(){});
       call.on('status', function(status) {
         assert.strictEqual(status.code, grpc.status.OK);
-        assert.deepEqual(status.metadata.metadata, ['yes']);
+        assert.deepEqual(status.metadata.trailer_present, ['yes']);
         done();
       });
     });
@@ -413,7 +502,7 @@ describe('Other conditions', function() {
       call.end();
       call.on('data', function(){});
       call.on('error', function(error) {
-        assert.deepEqual(error.metadata.metadata, ['yes']);
+        assert.deepEqual(error.metadata.trailer_present, ['yes']);
         done();
       });
     });
@@ -465,18 +554,17 @@ describe('Cancelling surface client', function() {
   var client;
   var server;
   before(function() {
-    var Server = grpc.buildServer([mathService]);
-    server = new Server({
-      'math.Math': {
-        'div': function(stream) {},
-        'divMany': function(stream) {},
-        'fib': function(stream) {},
-        'sum': function(stream) {}
-      }
+    server = new grpc.Server();
+    server.addProtoService(mathService, {
+      'div': function(stream) {},
+      'divMany': function(stream) {},
+      'fib': function(stream) {},
+      'sum': function(stream) {}
     });
     var port = server.bind('localhost:0');
     var Client = surface_client.makeProtobufClientConstructor(mathService);
     client = new Client('localhost:' + port);
+    server.start();
   });
   after(function() {
     server.shutdown();
diff --git a/src/objective-c/GRPCClient/GRPCCall.m b/src/objective-c/GRPCClient/GRPCCall.m
index 53e5abe177..9435bf2b35 100644
--- a/src/objective-c/GRPCClient/GRPCCall.m
+++ b/src/objective-c/GRPCClient/GRPCCall.m
@@ -35,10 +35,10 @@
 
 #include <grpc/grpc.h>
 #include <grpc/support/time.h>
+#import <RxLibrary/GRXConcurrentWriteable.h>
 
 #import "private/GRPCChannel.h"
 #import "private/GRPCCompletionQueue.h"
-#import "private/GRPCDelegateWrapper.h"
 #import "private/GRPCWrappedCall.h"
 #import "private/NSData+GRPC.h"
 #import "private/NSDictionary+GRPC.h"
@@ -78,9 +78,13 @@ NSString * const kGRPCStatusMetadataKey = @"io.grpc.StatusMetadataKey";
   // do. Particularly, in the face of errors, there's no ordering guarantee at
   // all. This wrapper over our actual writeable ensures thread-safety and
   // correct ordering.
-  GRPCDelegateWrapper *_responseWriteable;
+  GRXConcurrentWriteable *_responseWriteable;
   GRXWriter *_requestWriter;
 
+  // To create a retain cycle when a call is started, up until it finishes. See
+  // |startWithWriteable:| and |finishWithError:|.
+  GRPCCall *_self;
+
   NSMutableDictionary *_requestMetadata;
   NSMutableDictionary *_responseMetadata;
 }
@@ -143,8 +147,13 @@ NSString * const kGRPCStatusMetadataKey = @"io.grpc.StatusMetadataKey";
 #pragma mark Finish
 
 - (void)finishWithError:(NSError *)errorOrNil {
+  // If the call isn't retained anywhere else, it can be deallocated now.
+  _self = nil;
+
+  // If there were still request messages coming, stop them.
   _requestWriter.state = GRXWriterStateFinished;
   _requestWriter = nil;
+
   if (errorOrNil) {
     [_responseWriteable cancelWithError:errorOrNil];
   } else {
@@ -191,7 +200,7 @@ NSString * const kGRPCStatusMetadataKey = @"io.grpc.StatusMetadataKey";
     return;
   }
   __weak GRPCCall *weakSelf = self;
-  __weak GRPCDelegateWrapper *weakWriteable = _responseWriteable;
+  __weak GRXConcurrentWriteable *weakWriteable = _responseWriteable;
 
   dispatch_async(_callQueue, ^{
     [weakSelf startReadWithHandler:^(grpc_byte_buffer *message) {
@@ -216,7 +225,7 @@ NSString * const kGRPCStatusMetadataKey = @"io.grpc.StatusMetadataKey";
         [weakSelf cancelCall];
         return;
       }
-      [weakWriteable enqueueMessage:data completionHandler:^{
+      [weakWriteable enqueueValue:data completionHandler:^{
         [weakSelf startNextRead];
       }];
     }];
@@ -276,6 +285,7 @@ NSString * const kGRPCStatusMetadataKey = @"io.grpc.StatusMetadataKey";
 }
 
 - (void)writesFinishedWithError:(NSError *)errorOrNil {
+  _requestWriter = nil;
   if (errorOrNil) {
     [self cancel];
   } else {
@@ -335,12 +345,14 @@ NSString * const kGRPCStatusMetadataKey = @"io.grpc.StatusMetadataKey";
 #pragma mark GRXWriter implementation
 
 - (void)startWithWriteable:(id<GRXWriteable>)writeable {
-  // The following produces a retain cycle self:_responseWriteable:self, which is only
-  // broken when writesFinishedWithError: is sent to the wrapped writeable.
-  // Care is taken not to retain self strongly in any of the blocks used in
-  // the implementation of GRPCCall, so that the life of the instance is
-  // determined by this retain cycle.
-  _responseWriteable = [[GRPCDelegateWrapper alloc] initWithWriteable:writeable writer:self];
+  // Create a retain cycle so that this instance lives until the RPC finishes (or is cancelled).
+  // This makes RPCs in which the call isn't externally retained possible (as long as it is started
+  // before being autoreleased).
+  // Care is taken not to retain self strongly in any of the blocks used in this implementation, so
+  // that the life of the instance is determined by this retain cycle.
+  _self = self;
+
+  _responseWriteable = [[GRXConcurrentWriteable alloc] initWithWriteable:writeable];
   [self sendHeaders:_requestMetadata];
   [self invokeCall];
 }
diff --git a/src/objective-c/GRPCClient/private/GRPCCompletionQueue.m b/src/objective-c/GRPCClient/private/GRPCCompletionQueue.m
index 40aade4f9a..12535c9616 100644
--- a/src/objective-c/GRPCClient/private/GRPCCompletionQueue.m
+++ b/src/objective-c/GRPCClient/private/GRPCCompletionQueue.m
@@ -65,7 +65,8 @@
     dispatch_async(gDefaultConcurrentQueue, ^{
       while (YES) {
         // The following call blocks until an event is available.
-        grpc_event event = grpc_completion_queue_next(unmanagedQueue, gpr_inf_future);
+        grpc_event event = grpc_completion_queue_next(unmanagedQueue,
+                                                      gpr_inf_future(GPR_CLOCK_REALTIME));
         GRPCQueueCompletionHandler handler;
         switch (event.type) {
           case GRPC_OP_COMPLETE:
diff --git a/src/objective-c/GRPCClient/private/GRPCWrappedCall.m b/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
index 45f10f5d63..1db63df77f 100644
--- a/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
+++ b/src/objective-c/GRPCClient/private/GRPCWrappedCall.m
@@ -246,8 +246,11 @@
     if (!_queue) {
       return nil;
     }
-    _call = grpc_channel_create_call(channel.unmanagedChannel, _queue.unmanagedQueue,
-                                     path.UTF8String, host.UTF8String, gpr_inf_future);
+    _call = grpc_channel_create_call(channel.unmanagedChannel,
+                                     _queue.unmanagedQueue,
+                                     path.UTF8String,
+                                     host.UTF8String,
+                                     gpr_inf_future(GPR_CLOCK_REALTIME));
     if (_call == NULL) {
       return nil;
     }
diff --git a/src/objective-c/GRPCClient/private/GRPCDelegateWrapper.h b/src/objective-c/RxLibrary/GRXConcurrentWriteable.h
index 9a30a2f966..1080001905 100644
--- a/src/objective-c/GRPCClient/private/GRPCDelegateWrapper.h
+++ b/src/objective-c/RxLibrary/GRXConcurrentWriteable.h
@@ -33,49 +33,39 @@
 
 #import <Foundation/Foundation.h>
 
-#import <RxLibrary/GRXWriter.h>
+#import "GRXWriter.h"
+#import "GRXWriteable.h"
 
-@protocol GRXWriteable;
-
-// This is a thread-safe wrapper over a GRXWriteable instance. It lets one
-// enqueue calls to a GRXWriteable instance for the main thread, guaranteeing
-// that writesFinishedWithError: is the last message sent to it (no matter what
-// messages are sent to the wrapper, in what order, nor from which thread). It
-// also guarantees that, if cancelWithError: is called from the main thread
-// (e.g. by the app cancelling the writes), no further messages are sent to the
-// writeable except writesFinishedWithError:.
+// This is a thread-safe wrapper over a GRXWriteable instance. It lets one enqueue calls to a
+// GRXWriteable instance for the main thread, guaranteeing that writesFinishedWithError: is the last
+// message sent to it (no matter what messages are sent to the wrapper, in what order, nor from
+// which thread). It also guarantees that, if cancelWithError: is called from the main thread (e.g.
+// by the app cancelling the writes), no further messages are sent to the writeable except
+// writesFinishedWithError:.
 //
-// TODO(jcanizales): Let the user specify another queue for the writeable
-// callbacks.
-// TODO(jcanizales): Rename to GRXWriteableWrapper and move to the Rx library.
-@interface GRPCDelegateWrapper : NSObject
+// TODO(jcanizales): Let the user specify another queue for the writeable callbacks.
+@interface GRXConcurrentWriteable : NSObject
 
 // The GRXWriteable passed is the wrapped writeable.
-// Both the GRXWriter instance and the GRXWriteable instance are retained until
-// writesFinishedWithError: is sent to the writeable, and released after that.
-// This is used to create a retain cycle that keeps both objects alive until the
-// writing is explicitly finished.
-- (instancetype)initWithWriteable:(id<GRXWriteable>)writeable writer:(GRXWriter *)writer
-    NS_DESIGNATED_INITIALIZER;
+// The GRXWriteable instance is retained until writesFinishedWithError: is sent to it, and released
+// after that.
+- (instancetype)initWithWriteable:(id<GRXWriteable>)writeable NS_DESIGNATED_INITIALIZER;
 
 // Enqueues writeValue: to be sent to the writeable in the main thread.
 // The passed handler is invoked from the main thread after writeValue: returns.
-- (void)enqueueMessage:(NSData *)message completionHandler:(void (^)())handler;
+- (void)enqueueValue:(id)value completionHandler:(void (^)())handler;
 
-// Enqueues writesFinishedWithError:nil to be sent to the writeable in the main
-// thread. After that message is sent to the writeable, all other methods of
-// this object are effectively noops.
+// Enqueues writesFinishedWithError:nil to be sent to the writeable in the main thread. After that
+// message is sent to the writeable, all other methods of this object are effectively noops.
 - (void)enqueueSuccessfulCompletion;
 
-// If the writeable has not yet received a writesFinishedWithError: message, this
-// will enqueue one to be sent to it in the main thread, and cancel all other
-// pending messages to the writeable enqueued by this object (both past and
-// future).
+// If the writeable has not yet received a writesFinishedWithError: message, this will enqueue one
+// to be sent to it in the main thread, and cancel all other pending messages to the writeable
+// enqueued by this object (both past and future).
 // The error argument cannot be nil.
 - (void)cancelWithError:(NSError *)error;
 
-// Cancels all pending messages to the writeable enqueued by this object (both
-// past and future). Because the writeable won't receive writesFinishedWithError:,
-// this also releases the writeable and the writer.
+// Cancels all pending messages to the writeable enqueued by this object (both past and future).
+// Because the writeable won't receive writesFinishedWithError:, this also releases the writeable.
 - (void)cancelSilently;
 @end
diff --git a/src/objective-c/GRPCClient/private/GRPCDelegateWrapper.m b/src/objective-c/RxLibrary/GRXConcurrentWriteable.m
index 294cfb7e23..08bd079aea 100644
--- a/src/objective-c/GRPCClient/private/GRPCDelegateWrapper.m
+++ b/src/objective-c/RxLibrary/GRXConcurrentWriteable.m
@@ -31,45 +31,42 @@
  *
  */
 
-#import "GRPCDelegateWrapper.h"
+#import "GRXConcurrentWriteable.h"
 
 #import <RxLibrary/GRXWriteable.h>
 
-@interface GRPCDelegateWrapper ()
-// These are atomic so that cancellation can nillify them from any thread.
+@interface GRXConcurrentWriteable ()
+// This is atomic so that cancellation can nillify it from any thread.
 @property(atomic, strong) id<GRXWriteable> writeable;
-@property(atomic, strong) GRXWriter *writer;
 @end
 
-@implementation GRPCDelegateWrapper {
+@implementation GRXConcurrentWriteable {
   dispatch_queue_t _writeableQueue;
   // This ensures that writesFinishedWithError: is only sent once to the writeable.
   dispatch_once_t _alreadyFinished;
 }
 
 - (instancetype)init {
-  return [self initWithWriteable:nil writer:nil];
+  return [self initWithWriteable:nil];
 }
 
 // Designated initializer
-- (instancetype)initWithWriteable:(id<GRXWriteable>)writeable writer:(GRXWriter *)writer {
+- (instancetype)initWithWriteable:(id<GRXWriteable>)writeable {
   if (self = [super init]) {
     _writeableQueue = dispatch_get_main_queue();
     _writeable = writeable;
-    _writer = writer;
   }
   return self;
 }
 
-- (void)enqueueMessage:(NSData *)message completionHandler:(void (^)())handler {
+- (void)enqueueValue:(id)value completionHandler:(void (^)())handler {
   dispatch_async(_writeableQueue, ^{
-    // We're racing a possible cancellation performed by another thread. To turn
-    // all already-enqueued messages into noops, cancellation nillifies the
-    // writeable property. If we get it before it's nil, we won
-    // the race.
+    // We're racing a possible cancellation performed by another thread. To turn all already-
+    // enqueued messages into noops, cancellation nillifies the writeable property. If we get it
+    // before it's nil, we won the race.
     id<GRXWriteable> writeable = self.writeable;
     if (writeable) {
-      [writeable writeValue:message];
+      [writeable writeValue:value];
       handler();
     }
   });
@@ -78,13 +75,11 @@
 - (void)enqueueSuccessfulCompletion {
   dispatch_async(_writeableQueue, ^{
     dispatch_once(&_alreadyFinished, ^{
-      // Cancellation is now impossible. None of the other three blocks can run
-      // concurrently with this one.
+      // Cancellation is now impossible. None of the other three blocks can run concurrently with
+      // this one.
       [self.writeable writesFinishedWithError:nil];
-      // Break the retain cycle with writer, and skip any possible message to the
-      // wrapped writeable enqueued after this one.
+      // Skip any possible message to the wrapped writeable enqueued after this one.
       self.writeable = nil;
-      self.writer = nil;
     });
   });
 }
@@ -92,29 +87,24 @@
 - (void)cancelWithError:(NSError *)error {
   NSAssert(error, @"For a successful completion, use enqueueSuccessfulCompletion.");
   dispatch_once(&_alreadyFinished, ^{
-    // Skip any of the still-enqueued messages to the wrapped writeable. We use
-    // the atomic setter to nillify writer and writeable because we might be
-    // running concurrently with the blocks in _writeableQueue, and assignment
-    // with ARC isn't atomic.
+    // Skip any of the still-enqueued messages to the wrapped writeable. We use the atomic setter to
+    // nillify writeable because we might be running concurrently with the blocks in
+    // _writeableQueue, and assignment with ARC isn't atomic.
     id<GRXWriteable> writeable = self.writeable;
     self.writeable = nil;
 
     dispatch_async(_writeableQueue, ^{
       [writeable writesFinishedWithError:error];
-      // Break the retain cycle with writer.
-      self.writer = nil;
     });
   });
 }
 
 - (void)cancelSilently {
   dispatch_once(&_alreadyFinished, ^{
-    // Skip any of the still-enqueued messages to the wrapped writeable. We use
-    // the atomic setter to nillify writer and writeable because we might be
-    // running concurrently with the blocks in _writeableQueue, and assignment
-    // with ARC isn't atomic.
+    // Skip any of the still-enqueued messages to the wrapped writeable. We use the atomic setter to
+    // nillify writeable because we might be running concurrently with the blocks in
+    // _writeableQueue, and assignment with ARC isn't atomic.
     self.writeable = nil;
-    self.writer = nil;
   });
 }
 @end
diff --git a/src/objective-c/RxLibrary/GRXImmediateWriter.m b/src/objective-c/RxLibrary/GRXImmediateWriter.m
index b6d2b2cac0..3edae788ab 100644
--- a/src/objective-c/RxLibrary/GRXImmediateWriter.m
+++ b/src/objective-c/RxLibrary/GRXImmediateWriter.m
@@ -76,28 +76,15 @@
 }
 
 + (GRXWriter *)writerWithValue:(id)value {
-  if (value) {
-    return [self writerWithEnumerator:[NSEnumerator grx_enumeratorWithSingleValue:value]];
-  } else {
-    return [self emptyWriter];
-  }
+  return [self writerWithEnumerator:[NSEnumerator grx_enumeratorWithSingleValue:value]];
 }
 
 + (GRXWriter *)writerWithError:(NSError *)error {
-  if (error) {
-    return [self writerWithEnumerator:nil error:error];
-  } else {
-    return [self emptyWriter];
-  }
+  return [self writerWithEnumerator:nil error:error];
 }
 
 + (GRXWriter *)emptyWriter {
-  static GRXImmediateWriter *emptyWriter;
-  static dispatch_once_t onceToken;
-  dispatch_once(&onceToken, ^{
-    emptyWriter = [self writerWithEnumerator:nil error:nil];
-  });
-  return emptyWriter;
+  return [self writerWithEnumerator:nil error:nil];
 }
 
 #pragma mark Conformance with GRXWriter
diff --git a/src/objective-c/RxLibrary/private/GRXNSFastEnumerator.m b/src/objective-c/RxLibrary/private/GRXNSFastEnumerator.m
index 2050fa98ec..0387c9954e 100644
--- a/src/objective-c/RxLibrary/private/GRXNSFastEnumerator.m
+++ b/src/objective-c/RxLibrary/private/GRXNSFastEnumerator.m
@@ -59,7 +59,6 @@
 
 // Designated initializer.
 - (instancetype)initWithContainer:(id<NSFastEnumeration>)container {
-  NSAssert(container, @"container can't be nil");
   if ((self = [super init])) {
     _container = container;
   }
diff --git a/src/objective-c/generated_libraries/RemoteTestClient/RemoteTest.podspec b/src/objective-c/generated_libraries/RemoteTestClient/RemoteTest.podspec
index dd0dab352d..7cc9a040fe 100644
--- a/src/objective-c/generated_libraries/RemoteTestClient/RemoteTest.podspec
+++ b/src/objective-c/generated_libraries/RemoteTestClient/RemoteTest.podspec
@@ -7,7 +7,13 @@ Pod::Spec.new do |s|
   s.osx.deployment_target = "10.8"
 
   # Run protoc with the Objective-C and gRPC plugins to generate protocol messages and gRPC clients.
-  s.prepare_command = "protoc --objc_out=. --objcgrpc_out=. *.proto"
+  s.prepare_command = <<-CMD
+    cd ../../../..
+    # TODO(jcanizales): Make only Objective-C plugin.
+    make plugins
+    cd -
+    protoc --plugin=protoc-gen-grpc=../../../../bins/opt/grpc_objective_c_plugin --objc_out=. --grpc_out=. *.proto
+  CMD
 
   s.subspec "Messages" do |ms|
     ms.source_files = "*.pbobjc.{h,m}"
diff --git a/src/objective-c/generated_libraries/RouteGuideClient/RouteGuide.podspec b/src/objective-c/generated_libraries/RouteGuideClient/RouteGuide.podspec
index e26e62f5bb..0e8dacd1c4 100644
--- a/src/objective-c/generated_libraries/RouteGuideClient/RouteGuide.podspec
+++ b/src/objective-c/generated_libraries/RouteGuideClient/RouteGuide.podspec
@@ -7,7 +7,13 @@ Pod::Spec.new do |s|
   s.osx.deployment_target = "10.8"
 
   # Run protoc with the Objective-C and gRPC plugins to generate protocol messages and gRPC clients.
-  s.prepare_command = "protoc --objc_out=. --objcgrpc_out=. *.proto"
+  s.prepare_command = <<-CMD
+    cd ../../../..
+    # TODO(jcanizales): Make only Objective-C plugin.
+    make plugins
+    cd -
+    protoc --plugin=protoc-gen-grpc=../../../../bins/opt/grpc_objective_c_plugin --objc_out=. --grpc_out=. *.proto
+  CMD
 
   s.subspec "Messages" do |ms|
     ms.source_files = "*.pbobjc.{h,m}"
diff --git a/src/objective-c/tests/Tests.xcodeproj/project.pbxproj b/src/objective-c/tests/Tests.xcodeproj/project.pbxproj
index 34be705db2..f13fb8288b 100644
--- a/src/objective-c/tests/Tests.xcodeproj/project.pbxproj
+++ b/src/objective-c/tests/Tests.xcodeproj/project.pbxproj
@@ -391,7 +391,6 @@
 		635697DC1B14FC11007A7283 /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
-				OTHER_LDFLAGS = "-ObjC";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
 			};
@@ -400,7 +399,6 @@
 		635697DD1B14FC11007A7283 /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
-				OTHER_LDFLAGS = "-ObjC";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
 			};
diff --git a/src/objective-c/tests/Tests.xcodeproj/xcshareddata/xcschemes/AllTests.xcscheme b/src/objective-c/tests/Tests.xcodeproj/xcshareddata/xcschemes/AllTests.xcscheme
new file mode 100644
index 0000000000..3a6e2c3591
--- /dev/null
+++ b/src/objective-c/tests/Tests.xcodeproj/xcshareddata/xcschemes/AllTests.xcscheme
@@ -0,0 +1,104 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "0630"
+   version = "1.3">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "NO"
+            buildForArchiving = "NO"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "63423F431B150A5F006CF63C"
+               BuildableName = "AllTests.xctest"
+               BlueprintName = "AllTests"
+               ReferencedContainer = "container:Tests.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      buildConfiguration = "Debug">
+      <Testables>
+         <TestableReference
+            skipped = "NO">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "63423F431B150A5F006CF63C"
+               BuildableName = "AllTests.xctest"
+               BlueprintName = "AllTests"
+               ReferencedContainer = "container:Tests.xcodeproj">
+            </BuildableReference>
+            <SkippedTests>
+               <Test
+                  Identifier = "LocalClearTextTests">
+               </Test>
+               <Test
+                  Identifier = "LocalClearTextTests/testConnectionToLocalServer">
+               </Test>
+            </SkippedTests>
+         </TestableReference>
+      </Testables>
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "63423F431B150A5F006CF63C"
+            BuildableName = "AllTests.xctest"
+            BlueprintName = "AllTests"
+            ReferencedContainer = "container:Tests.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+   </TestAction>
+   <LaunchAction
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      buildConfiguration = "Debug"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      allowLocationSimulation = "YES">
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "63423F431B150A5F006CF63C"
+            BuildableName = "AllTests.xctest"
+            BlueprintName = "AllTests"
+            ReferencedContainer = "container:Tests.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+      <AdditionalOptions>
+      </AdditionalOptions>
+   </LaunchAction>
+   <ProfileAction
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      buildConfiguration = "Release"
+      debugDocumentVersioning = "YES">
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "63423F431B150A5F006CF63C"
+            BuildableName = "AllTests.xctest"
+            BlueprintName = "AllTests"
+            ReferencedContainer = "container:Tests.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>
diff --git a/src/objective-c/tests/run_tests.sh b/src/objective-c/tests/run_tests.sh
new file mode 100755
index 0000000000..37fced3a62
--- /dev/null
+++ b/src/objective-c/tests/run_tests.sh
@@ -0,0 +1,49 @@
+#!/bin/bash
+# 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.
+
+set -e
+
+cd $(dirname $0)
+
+# TODO(jcanizales): Remove when Cocoapods issue #3823 is resolved.
+export COCOAPODS_DISABLE_DETERMINISTIC_UUIDS=YES
+pod install
+
+# xcodebuild is very verbose. We filter its output and tell Bash to fail if any
+# element of the pipe fails.
+# TODO(jcanizales): Use xctool instead? Issue #2540.
+set -o pipefail
+XCODEBUILD_FILTER='(^===|^\*\*|\bfatal\b|\berror\b|\bwarning\b|\bfail)'
+xcodebuild \
+    -workspace Tests.xcworkspace \
+    -scheme AllTests \
+    -destination name="iPhone 6" \
+    test \
+    | egrep "$XCODEBUILD_FILTER" -
diff --git a/src/php/ext/grpc/server.c b/src/php/ext/grpc/server.c
index c319526e42..8b8d5b2f47 100644
--- a/src/php/ext/grpc/server.c
+++ b/src/php/ext/grpc/server.c
@@ -64,6 +64,7 @@ void free_wrapped_grpc_server(void *object TSRMLS_DC) {
   wrapped_grpc_server *server = (wrapped_grpc_server *)object;
   if (server->wrapped != NULL) {
     grpc_server_shutdown_and_notify(server->wrapped, completion_queue, NULL);
+    grpc_server_cancel_all_calls(server->wrapped);
     grpc_completion_queue_pluck(completion_queue, NULL,
                                 gpr_inf_future(GPR_CLOCK_REALTIME));
     grpc_server_destroy(server->wrapped);
diff --git a/src/php/tests/unit_tests/EndToEndTest.php b/src/php/tests/unit_tests/EndToEndTest.php
index 296873fa8f..2980dca4a7 100755
--- a/src/php/tests/unit_tests/EndToEndTest.php
+++ b/src/php/tests/unit_tests/EndToEndTest.php
@@ -61,7 +61,6 @@ class EndToEndTest extends PHPUnit_Framework_TestCase{
 
     $event = $this->server->requestCall();
     $this->assertSame('dummy_method', $event->method);
-    $this->assertSame([], $event->metadata);
     $server_call = $event->call;
 
     $event = $server_call->startBatch([
@@ -83,7 +82,6 @@ class EndToEndTest extends PHPUnit_Framework_TestCase{
         Grpc\OP_RECV_STATUS_ON_CLIENT => true
                                  ]);
 
-    $this->assertSame([], $event->metadata);
     $status = $event->status;
     $this->assertSame([], $status->metadata);
     $this->assertSame(Grpc\STATUS_OK, $status->code);
diff --git a/src/php/tests/unit_tests/SecureEndToEndTest.php b/src/php/tests/unit_tests/SecureEndToEndTest.php
index 0c18cd3e91..f91c006da5 100755
--- a/src/php/tests/unit_tests/SecureEndToEndTest.php
+++ b/src/php/tests/unit_tests/SecureEndToEndTest.php
@@ -73,7 +73,6 @@ class SecureEndToEndTest extends PHPUnit_Framework_TestCase{
 
     $event = $this->server->requestCall();
     $this->assertSame('dummy_method', $event->method);
-    $this->assertSame([], $event->metadata);
     $server_call = $event->call;
 
     $event = $server_call->startBatch([
diff --git a/src/python/src/grpc/_adapter/_c/utility.c b/src/python/src/grpc/_adapter/_c/utility.c
index 000c8d0c38..d9f911a41a 100644
--- a/src/python/src/grpc/_adapter/_c/utility.c
+++ b/src/python/src/grpc/_adapter/_c/utility.c
@@ -489,10 +489,10 @@ PyObject *pygrpc_cast_metadata_array_to_pyseq(grpc_metadata_array metadata) {
 void pygrpc_byte_buffer_to_bytes(
     grpc_byte_buffer *buffer, char **result, size_t *result_size) {
   grpc_byte_buffer_reader reader;
-  grpc_byte_buffer_reader_init(&reader, buffer);
   gpr_slice slice;
   char *read_result = NULL;
   size_t size = 0;
+  grpc_byte_buffer_reader_init(&reader, buffer);
   while (grpc_byte_buffer_reader_next(&reader, &slice)) {
     read_result = gpr_realloc(read_result, size + GPR_SLICE_LENGTH(slice));
     memcpy(read_result + size, GPR_SLICE_START_PTR(slice),
diff --git a/src/python/src/grpc/_adapter/_low_test.py b/src/python/src/grpc/_adapter/_low_test.py
index 268e5fe765..a49cd007bf 100644
--- a/src/python/src/grpc/_adapter/_low_test.py
+++ b/src/python/src/grpc/_adapter/_low_test.py
@@ -129,7 +129,10 @@ class InsecureServerInsecureClient(unittest.TestCase):
     self.assertIsInstance(request_event.call, _low.Call)
     self.assertIs(server_request_tag, request_event.tag)
     self.assertEquals(1, len(request_event.results))
-    self.assertEquals(dict(client_initial_metadata), dict(request_event.results[0].initial_metadata))
+    got_initial_metadata = dict(request_event.results[0].initial_metadata)
+    self.assertEquals(
+        dict(client_initial_metadata),
+        dict((x, got_initial_metadata[x]) for x in zip(*client_initial_metadata)[0]))
     self.assertEquals(METHOD, request_event.call_details.method)
     self.assertEquals(HOST, request_event.call_details.host)
     self.assertLess(abs(DEADLINE - request_event.call_details.deadline), DEADLINE_TOLERANCE)
diff --git a/src/python/src/grpc/_links/_transmission_test.py b/src/python/src/grpc/_links/_transmission_test.py
index c5ef1edb25..3eeec03f46 100644
--- a/src/python/src/grpc/_links/_transmission_test.py
+++ b/src/python/src/grpc/_links/_transmission_test.py
@@ -93,8 +93,13 @@ class TransmissionTest(test_cases.TransmissionTest, unittest.TestCase):
   def create_service_completion(self):
     return _intermediary_low.Code.OK, 'An exuberant test "details" message!'
 
-  def assertMetadataEqual(self, original_metadata, transmitted_metadata):
-    self.assertSequenceEqual(original_metadata, transmitted_metadata)
+  def assertMetadataTransmitted(self, original_metadata, transmitted_metadata):
+    # we need to filter out any additional metadata added in transmitted_metadata
+    # since implementations are allowed to add to what is sent (in any position)
+    keys, _ = zip(*original_metadata)
+    self.assertSequenceEqual(
+        original_metadata,
+        [x for x in transmitted_metadata if x[0] in keys])
 
 
 class RoundTripTest(unittest.TestCase):
diff --git a/src/python/src/grpc/framework/interfaces/links/test_cases.py b/src/python/src/grpc/framework/interfaces/links/test_cases.py
index 3ac212ebdf..bf1f09d99d 100644
--- a/src/python/src/grpc/framework/interfaces/links/test_cases.py
+++ b/src/python/src/grpc/framework/interfaces/links/test_cases.py
@@ -161,8 +161,8 @@ class TransmissionTest(object):
     raise NotImplementedError()
 
   @abc.abstractmethod
-  def assertMetadataEqual(self, original_metadata, transmitted_metadata):
-    """Asserts that two metadata objects are equal.
+  def assertMetadataTransmitted(self, original_metadata, transmitted_metadata):
+    """Asserts that transmitted_metadata contains original_metadata.
 
     Args:
       original_metadata: A metadata object used in this test.
@@ -170,7 +170,8 @@ class TransmissionTest(object):
         through the system under test.
 
     Raises:
-      AssertionError: if the two metadata objects are not equal.
+      AssertionError: if the transmitted_metadata object does not contain
+        original_metadata.
     """
     raise NotImplementedError()
 
@@ -239,7 +240,7 @@ class TransmissionTest(object):
         self.assertFalse(initial_metadata_seen)
         self.assertFalse(seen_payloads)
         self.assertFalse(terminal_metadata_seen)
-        self.assertMetadataEqual(initial_metadata, ticket.initial_metadata)
+        self.assertMetadataTransmitted(initial_metadata, ticket.initial_metadata)
         initial_metadata_seen = True
 
       if ticket.payload is not None:
@@ -248,7 +249,7 @@ class TransmissionTest(object):
 
       if ticket.terminal_metadata is not None:
         self.assertFalse(terminal_metadata_seen)
-        self.assertMetadataEqual(terminal_metadata, ticket.terminal_metadata)
+        self.assertMetadataTransmitted(terminal_metadata, ticket.terminal_metadata)
         terminal_metadata_seen = True
     self.assertSequenceEqual(payloads, seen_payloads)
 
diff --git a/src/ruby/spec/generic/rpc_server_spec.rb b/src/ruby/spec/generic/rpc_server_spec.rb
index f2403de77c..0326f6e894 100644
--- a/src/ruby/spec/generic/rpc_server_spec.rb
+++ b/src/ruby/spec/generic/rpc_server_spec.rb
@@ -35,6 +35,14 @@ def load_test_certs
   files.map { |f| File.open(File.join(test_root, f)).read }
 end
 
+def check_md(wanted_md, received_md)
+  wanted_md.zip(received_md).each do |w, r|
+    w.each do |key, value|
+      expect(r[key]).to eq(value)
+    end
+  end
+end
+
 # A test message
 class EchoMsg
   def self.marshal(_o)
@@ -376,7 +384,7 @@ describe GRPC::RpcServer do
         stub = EchoStub.new(@host, **client_opts)
         expect(stub.an_rpc(req, k1: 'v1', k2: 'v2')).to be_a(EchoMsg)
         wanted_md = [{ 'k1' => 'v1', 'k2' => 'v2' }]
-        expect(service.received_md).to eq(wanted_md)
+        check_md(wanted_md, service.received_md)
         @srv.stop
         t.join
       end
@@ -391,7 +399,7 @@ describe GRPC::RpcServer do
         deadline = service.delay + 1.0 # wait for long enough
         expect(stub.an_rpc(req, deadline, k1: 'v1', k2: 'v2')).to be_a(EchoMsg)
         wanted_md = [{ 'k1' => 'v1', 'k2' => 'v2' }]
-        expect(service.received_md).to eq(wanted_md)
+        check_md(wanted_md, service.received_md)
         @srv.stop
         t.join
       end
@@ -443,7 +451,7 @@ describe GRPC::RpcServer do
         expect(stub.an_rpc(req, k1: 'v1', k2: 'v2')).to be_a(EchoMsg)
         wanted_md = [{ 'k1' => 'updated-v1', 'k2' => 'v2',
                        'jwt_aud_uri' => "https://#{@host}/EchoService" }]
-        expect(service.received_md).to eq(wanted_md)
+        check_md(wanted_md, service.received_md)
         @srv.stop
         t.join
       end
@@ -535,7 +543,9 @@ describe GRPC::RpcServer do
           'method' => '/EchoService/an_rpc',
           'connect_k1' => 'connect_v1'
         }
-        expect(op.metadata).to eq(wanted_md)
+        wanted_md.each do |key, value|
+          expect(op.metadata[key]).to eq(value)
+        end
         @srv.stop
         t.join
       end
diff --git a/templates/Makefile.template b/templates/Makefile.template
index 044db4dbfe..1e46db11dc 100644
--- a/templates/Makefile.template
+++ b/templates/Makefile.template
@@ -159,7 +159,7 @@ CC_tsan = clang
 CXX_tsan = clang++
 LD_tsan = clang
 LDXX_tsan = clang++
-CPPFLAGS_tsan = -O0 -fsanitize=thread -fno-omit-frame-pointer
+CPPFLAGS_tsan = -O0 -fsanitize=thread -fno-omit-frame-pointer -Wno-error=unused-command-line-argument
 LDFLAGS_tsan = -fsanitize=thread
 DEFINES_tsan = NDEBUG GRPC_TEST_SLOWDOWN_BUILD_FACTOR=10
 
@@ -169,7 +169,7 @@ CC_asan = clang
 CXX_asan = clang++
 LD_asan = clang
 LDXX_asan = clang++
-CPPFLAGS_asan = -O0 -fsanitize=address -fno-omit-frame-pointer
+CPPFLAGS_asan = -O0 -fsanitize=address -fno-omit-frame-pointer -Wno-error=unused-command-line-argument
 LDFLAGS_asan = -fsanitize=address
 DEFINES_asan = GRPC_TEST_SLOWDOWN_BUILD_FACTOR=3
 
@@ -179,7 +179,7 @@ CC_msan = clang
 CXX_msan = clang++-libc++
 LD_msan = clang
 LDXX_msan = clang++-libc++
-CPPFLAGS_msan = -O0 -fsanitize=memory -fsanitize-memory-track-origins -fno-omit-frame-pointer -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1
+CPPFLAGS_msan = -O0 -fsanitize=memory -fsanitize-memory-track-origins -fno-omit-frame-pointer -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1 -Wno-error=unused-command-line-argument
 OPENSSL_CFLAGS_msan = -DPURIFY
 LDFLAGS_msan = -fsanitize=memory -DGTEST_HAS_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=1
 DEFINES_msan = NDEBUG GRPC_TEST_SLOWDOWN_BUILD_FACTOR=4
@@ -190,7 +190,7 @@ CC_ubsan = clang
 CXX_ubsan = clang++
 LD_ubsan = clang
 LDXX_ubsan = clang++
-CPPFLAGS_ubsan = -O1 -fsanitize=undefined -fno-omit-frame-pointer
+CPPFLAGS_ubsan = -O1 -fsanitize=undefined -fno-omit-frame-pointer -Wno-error=unused-command-line-argument
 OPENSSL_CFLAGS_ubsan = -DPURIFY
 LDFLAGS_ubsan = -fsanitize=undefined
 DEFINES_ubsan = NDEBUG GRPC_TEST_SLOWDOWN_BUILD_FACTOR=3
@@ -255,10 +255,6 @@ HOST_CXX = $(CXX)
 HOST_LD = $(LD)
 HOST_LDXX = $(LDXX)
 
-CPPFLAGS += $(CPPFLAGS_$(CONFIG))
-DEFINES += $(DEFINES_$(CONFIG)) INSTALL_PREFIX=\"$(prefix)\"
-LDFLAGS += $(LDFLAGS_$(CONFIG))
-
 ifdef EXTRA_DEFINES
 DEFINES += $(EXTRA_DEFINES)
 endif
@@ -272,6 +268,10 @@ endif
 CPPFLAGS += -g -Wall -Wextra -Werror -Wno-long-long -Wno-unused-parameter
 LDFLAGS += -g
 
+CPPFLAGS += $(CPPFLAGS_$(CONFIG))
+DEFINES += $(DEFINES_$(CONFIG)) INSTALL_PREFIX=\"$(prefix)\"
+LDFLAGS += $(LDFLAGS_$(CONFIG))
+
 ifneq ($(SYSTEM),MINGW32)
 PIC_CPPFLAGS = -fPIC
 CPPFLAGS += -fPIC
@@ -816,7 +816,7 @@ run_dep_checks:
 
 $(LIBDIR)/$(CONFIG)/zlib/libz.a:
 	$(E) "[MAKE]    Building zlib"
-	$(Q)(cd third_party/zlib ; CC="$(CC)" CFLAGS="$(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG))" ./configure --static)
+	$(Q)(cd third_party/zlib ; CC="$(CC)" CFLAGS="$(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG)) $(ZLIB_CFLAGS_EXTRA)" ./configure --static)
 	$(Q)$(MAKE) -C third_party/zlib clean
 	$(Q)$(MAKE) -C third_party/zlib
 	$(Q)mkdir -p $(LIBDIR)/$(CONFIG)/zlib
@@ -825,7 +825,7 @@ $(LIBDIR)/$(CONFIG)/zlib/libz.a:
 $(LIBDIR)/$(CONFIG)/openssl/libssl.a:
 	$(E) "[MAKE]    Building openssl for $(SYSTEM)"
 ifeq ($(SYSTEM),Darwin)
-	$(Q)(cd third_party/openssl ; CC="$(CC) $(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_$(CONFIG))" ./Configure darwin64-x86_64-cc)
+	$(Q)(cd third_party/openssl ; CC="$(CC) $(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_EXTRA)" ./Configure darwin64-x86_64-cc)
 else
 ifeq ($(SYSTEM),MINGW32)
 	@echo "We currently don't have a good way to compile OpenSSL in-place under msys."
@@ -846,7 +846,7 @@ ifeq ($(SYSTEM),MINGW32)
 	@echo "  CPPFLAGS=-I/c/OpenSSL-Win64/include LDFLAGS=-L/c/OpenSSL-Win64 make"
 	@false
 else
-	$(Q)(cd third_party/openssl ; CC="$(CC) $(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_$(CONFIG))" ./config no-asm $(OPENSSL_CONFIG_$(CONFIG)))
+	$(Q)(cd third_party/openssl ; CC="$(CC) $(PIC_CPPFLAGS) -fvisibility=hidden $(CPPFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_$(CONFIG)) $(OPENSSL_CFLAGS_EXTRA)" ./config no-asm $(OPENSSL_CONFIG_$(CONFIG)))
 endif
 endif
 	$(Q)$(MAKE) -C third_party/openssl clean
@@ -860,7 +860,7 @@ third_party/protobuf/configure:
 
 $(LIBDIR)/$(CONFIG)/protobuf/libprotobuf.a: third_party/protobuf/configure
 	$(E) "[MAKE]    Building protobuf"
-	$(Q)(cd third_party/protobuf ; CC="$(CC)" CXX="$(CXX)" LDFLAGS="$(LDFLAGS_$(CONFIG)) -g" CPPFLAGS="$(PIC_CPPFLAGS) $(CPPFLAGS_$(CONFIG)) -g" ./configure --disable-shared --enable-static)
+	$(Q)(cd third_party/protobuf ; CC="$(CC)" CXX="$(CXX)" LDFLAGS="$(LDFLAGS_$(CONFIG)) -g $(PROTOBUF_LDFLAGS_EXTRA)" CPPFLAGS="$(PIC_CPPFLAGS) $(CPPFLAGS_$(CONFIG)) -g $(PROTOBUF_CPPFLAGS_EXTRA)" ./configure --disable-shared --enable-static)
 	$(Q)$(MAKE) -C third_party/protobuf clean
 	$(Q)$(MAKE) -C third_party/protobuf
 	$(Q)mkdir -p $(LIBDIR)/$(CONFIG)/protobuf
diff --git a/templates/gRPC.podspec.template b/templates/gRPC.podspec.template
index 495ea49c9c..d675a1a7f0 100644
--- a/templates/gRPC.podspec.template
+++ b/templates/gRPC.podspec.template
@@ -61,14 +61,14 @@ def grpc_private_headers(libs):
 %>
 Pod::Spec.new do |s|
   s.name     = 'gRPC'
-  s.version  = '0.6.0'
+  s.version  = '0.7.0'
   s.summary  = 'gRPC client library for iOS/OSX'
   s.homepage = 'http://www.grpc.io'
   s.license  = 'New BSD'
   s.authors  = { 'The gRPC contributors' => 'grpc-packages@google.com' }
 
   # s.source = { :git => 'https://github.com/grpc/grpc.git',
-  #              :tag => 'release-0_9_1-objectivec-0.5.1' }
+  #              :tag => 'release-0_10_0-objectivec-0.6.0' }
 
   s.ios.deployment_target = '6.0'
   s.osx.deployment_target = '10.8'
@@ -95,6 +95,8 @@ Pod::Spec.new do |s|
     ss.requires_arc = false
     ss.libraries = 'z'
     ss.dependency 'OpenSSL', '~> 1.0.200'
+
+    # ss.compiler_flags = '-GCC_WARN_INHIBIT_ALL_WARNINGS', '-w'
   end
 
   # This is a workaround for Cocoapods Issue #1437.
diff --git a/test/core/end2end/dualstack_socket_test.c b/test/core/end2end/dualstack_socket_test.c
index 7d3568c22e..05ad42ca1f 100644
--- a/test/core/end2end/dualstack_socket_test.c
+++ b/test/core/end2end/dualstack_socket_test.c
@@ -211,6 +211,10 @@ void test_connect(const char *server_host, const char *client_host, int port,
   drain_cq(cq);
   grpc_completion_queue_destroy(cq);
 
+  grpc_metadata_array_destroy(&initial_metadata_recv);
+  grpc_metadata_array_destroy(&trailing_metadata_recv);
+  grpc_metadata_array_destroy(&request_metadata_recv);
+
   grpc_call_details_destroy(&call_details);
   gpr_free(details);
 }
diff --git a/test/core/iomgr/alarm_test.c b/test/core/iomgr/alarm_test.c
index 362eb5fe63..55aa517529 100644
--- a/test/core/iomgr/alarm_test.c
+++ b/test/core/iomgr/alarm_test.c
@@ -41,6 +41,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include <grpc/grpc.h>
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 #include <grpc/support/sync.h>
@@ -100,7 +101,7 @@ static void test_grpc_alarm(void) {
   alarm_arg arg2;
   void *fdone;
 
-  grpc_iomgr_init();
+  grpc_init();
 
   arg.counter = 0;
   arg.success = SUCCESS_NOT_SET;
@@ -113,7 +114,7 @@ static void test_grpc_alarm(void) {
   gpr_event_init(&arg.fcb_arg);
 
   grpc_alarm_init(&alarm, GRPC_TIMEOUT_MILLIS_TO_DEADLINE(100), alarm_cb, &arg,
-                  gpr_now(GPR_CLOCK_REALTIME));
+                  gpr_now(GPR_CLOCK_MONOTONIC));
 
   alarm_deadline = GRPC_TIMEOUT_SECONDS_TO_DEADLINE(1);
   gpr_mu_lock(&arg.mu);
@@ -165,7 +166,7 @@ static void test_grpc_alarm(void) {
   gpr_event_init(&arg2.fcb_arg);
 
   grpc_alarm_init(&alarm_to_cancel, GRPC_TIMEOUT_MILLIS_TO_DEADLINE(100),
-                  alarm_cb, &arg2, gpr_now(GPR_CLOCK_REALTIME));
+                  alarm_cb, &arg2, gpr_now(GPR_CLOCK_MONOTONIC));
   grpc_alarm_cancel(&alarm_to_cancel);
 
   alarm_deadline = GRPC_TIMEOUT_SECONDS_TO_DEADLINE(1);
@@ -214,7 +215,7 @@ static void test_grpc_alarm(void) {
   gpr_mu_destroy(&arg2.mu);
   gpr_free(arg2.followup_closure);
 
-  grpc_iomgr_shutdown();
+  grpc_shutdown();
 }
 
 int main(int argc, char **argv) {
diff --git a/test/core/iomgr/endpoint_tests.c b/test/core/iomgr/endpoint_tests.c
index 0cfba5fac8..cb6adc58cf 100644
--- a/test/core/iomgr/endpoint_tests.c
+++ b/test/core/iomgr/endpoint_tests.c
@@ -254,7 +254,7 @@ static void read_and_write_test(grpc_endpoint_test_config config,
 
   gpr_mu_lock(GRPC_POLLSET_MU(g_pollset));
   while (!state.read_done || !state.write_done) {
-    GPR_ASSERT(gpr_time_cmp(gpr_now(GPR_CLOCK_REALTIME), deadline) < 0);
+    GPR_ASSERT(gpr_time_cmp(gpr_now(GPR_CLOCK_MONOTONIC), deadline) < 0);
     grpc_pollset_work(g_pollset, deadline);
   }
   gpr_mu_unlock(GRPC_POLLSET_MU(g_pollset));
@@ -350,14 +350,14 @@ static void shutdown_during_write_test(grpc_endpoint_test_config config,
         deadline = GRPC_TIMEOUT_SECONDS_TO_DEADLINE(10);
         gpr_mu_lock(GRPC_POLLSET_MU(g_pollset));
         while (!write_st.done) {
-          GPR_ASSERT(gpr_time_cmp(gpr_now(GPR_CLOCK_REALTIME), deadline) < 0);
+          GPR_ASSERT(gpr_time_cmp(gpr_now(deadline.clock_type), deadline) < 0);
           grpc_pollset_work(g_pollset, deadline);
         }
         gpr_mu_unlock(GRPC_POLLSET_MU(g_pollset));
         grpc_endpoint_destroy(write_st.ep);
         gpr_mu_lock(GRPC_POLLSET_MU(g_pollset));
         while (!read_st.done) {
-          GPR_ASSERT(gpr_time_cmp(gpr_now(GPR_CLOCK_REALTIME), deadline) < 0);
+          GPR_ASSERT(gpr_time_cmp(gpr_now(deadline.clock_type), deadline) < 0);
           grpc_pollset_work(g_pollset, deadline);
         }
         gpr_mu_unlock(GRPC_POLLSET_MU(g_pollset));
diff --git a/test/core/iomgr/fd_posix_test.c b/test/core/iomgr/fd_posix_test.c
index cd268661db..7d00c098cc 100644
--- a/test/core/iomgr/fd_posix_test.c
+++ b/test/core/iomgr/fd_posix_test.c
@@ -249,7 +249,7 @@ static int server_start(server *sv) {
 static void server_wait_and_shutdown(server *sv) {
   gpr_mu_lock(GRPC_POLLSET_MU(&g_pollset));
   while (!sv->done) {
-    grpc_pollset_work(&g_pollset, gpr_inf_future(GPR_CLOCK_REALTIME));
+    grpc_pollset_work(&g_pollset, gpr_inf_future(GPR_CLOCK_MONOTONIC));
   }
   gpr_mu_unlock(GRPC_POLLSET_MU(&g_pollset));
 }
@@ -356,7 +356,7 @@ static void client_start(client *cl, int port) {
 static void client_wait_and_shutdown(client *cl) {
   gpr_mu_lock(GRPC_POLLSET_MU(&g_pollset));
   while (!cl->done) {
-    grpc_pollset_work(&g_pollset, gpr_inf_future(GPR_CLOCK_REALTIME));
+    grpc_pollset_work(&g_pollset, gpr_inf_future(GPR_CLOCK_MONOTONIC));
   }
   gpr_mu_unlock(GRPC_POLLSET_MU(&g_pollset));
 }
@@ -445,7 +445,7 @@ static void test_grpc_fd_change(void) {
   /* And now wait for it to run. */
   gpr_mu_lock(GRPC_POLLSET_MU(&g_pollset));
   while (a.cb_that_ran == NULL) {
-    grpc_pollset_work(&g_pollset, gpr_inf_future(GPR_CLOCK_REALTIME));
+    grpc_pollset_work(&g_pollset, gpr_inf_future(GPR_CLOCK_MONOTONIC));
   }
   GPR_ASSERT(a.cb_that_ran == first_read_callback);
   gpr_mu_unlock(GRPC_POLLSET_MU(&g_pollset));
@@ -463,7 +463,7 @@ static void test_grpc_fd_change(void) {
 
   gpr_mu_lock(GRPC_POLLSET_MU(&g_pollset));
   while (b.cb_that_ran == NULL) {
-    grpc_pollset_work(&g_pollset, gpr_inf_future(GPR_CLOCK_REALTIME));
+    grpc_pollset_work(&g_pollset, gpr_inf_future(GPR_CLOCK_MONOTONIC));
   }
   /* Except now we verify that second_read_callback ran instead */
   GPR_ASSERT(b.cb_that_ran == second_read_callback);
diff --git a/test/core/iomgr/tcp_client_posix_test.c b/test/core/iomgr/tcp_client_posix_test.c
index 637886a738..38b7b5909d 100644
--- a/test/core/iomgr/tcp_client_posix_test.c
+++ b/test/core/iomgr/tcp_client_posix_test.c
@@ -196,13 +196,13 @@ void test_times_out(void) {
   gpr_mu_lock(GRPC_POLLSET_MU(&g_pollset));
   while (gpr_time_cmp(gpr_time_add(connect_deadline,
                                    gpr_time_from_seconds(2, GPR_TIMESPAN)),
-                      gpr_now(GPR_CLOCK_REALTIME)) > 0) {
+                      gpr_now(connect_deadline.clock_type)) > 0) {
     int is_after_deadline =
-        gpr_time_cmp(connect_deadline, gpr_now(GPR_CLOCK_REALTIME)) <= 0;
+        gpr_time_cmp(connect_deadline, gpr_now(GPR_CLOCK_MONOTONIC)) <= 0;
     if (is_after_deadline &&
         gpr_time_cmp(gpr_time_add(connect_deadline,
                                   gpr_time_from_seconds(1, GPR_TIMESPAN)),
-                     gpr_now(GPR_CLOCK_REALTIME)) > 0) {
+                     gpr_now(GPR_CLOCK_MONOTONIC)) > 0) {
       /* allow some slack before insisting that things be done */
     } else {
       GPR_ASSERT(g_connections_complete ==
diff --git a/test/core/iomgr/tcp_server_posix_test.c b/test/core/iomgr/tcp_server_posix_test.c
index 83252a889b..f8d0fe8217 100644
--- a/test/core/iomgr/tcp_server_posix_test.c
+++ b/test/core/iomgr/tcp_server_posix_test.c
@@ -135,7 +135,7 @@ static void test_connect(int n) {
 
     gpr_log(GPR_DEBUG, "wait");
     while (g_nconnects == nconnects_before &&
-           gpr_time_cmp(deadline, gpr_now(GPR_CLOCK_REALTIME)) > 0) {
+           gpr_time_cmp(deadline, gpr_now(deadline.clock_type)) > 0) {
       grpc_pollset_work(&g_pollset, deadline);
     }
     gpr_log(GPR_DEBUG, "wait done");
diff --git a/test/core/util/test_config.h b/test/core/util/test_config.h
index 063c797ce9..7028ade7b2 100644
--- a/test/core/util/test_config.h
+++ b/test/core/util/test_config.h
@@ -52,12 +52,12 @@ extern "C" {
   (GRPC_TEST_SLOWDOWN_BUILD_FACTOR * GRPC_TEST_SLOWDOWN_MACHINE_FACTOR)
 
 #define GRPC_TIMEOUT_SECONDS_TO_DEADLINE(x)                                \
-  gpr_time_add(gpr_now(GPR_CLOCK_REALTIME),                                \
+  gpr_time_add(gpr_now(GPR_CLOCK_MONOTONIC),                               \
                gpr_time_from_micros(GRPC_TEST_SLOWDOWN_FACTOR * 1e6 * (x), \
                                     GPR_TIMESPAN))
 
 #define GRPC_TIMEOUT_MILLIS_TO_DEADLINE(x)                                 \
-  gpr_time_add(gpr_now(GPR_CLOCK_REALTIME),                                \
+  gpr_time_add(gpr_now(GPR_CLOCK_MONOTONIC),                               \
                gpr_time_from_micros(GRPC_TEST_SLOWDOWN_FACTOR * 1e3 * (x), \
                                     GPR_TIMESPAN))
 
diff --git a/test/cpp/client/credentials_test.cc b/test/cpp/client/credentials_test.cc
index ee94f455a4..bbf7705f0a 100644
--- a/test/cpp/client/credentials_test.cc
+++ b/test/cpp/client/credentials_test.cc
@@ -47,7 +47,7 @@ class CredentialsTest : public ::testing::Test {
 
 TEST_F(CredentialsTest, InvalidServiceAccountCreds) {
   std::shared_ptr<Credentials> bad1 = ServiceAccountCredentials("", "", 1);
-  EXPECT_EQ(nullptr, bad1.get());
+  EXPECT_EQ(static_cast<Credentials *>(nullptr), bad1.get());
 }
 
 }  // namespace testing
diff --git a/test/cpp/common/secure_auth_context_test.cc b/test/cpp/common/secure_auth_context_test.cc
index f18a04178e..d0243a5432 100644
--- a/test/cpp/common/secure_auth_context_test.cc
+++ b/test/cpp/common/secure_auth_context_test.cc
@@ -92,26 +92,6 @@ TEST_F(SecureAuthContextTest, Iterators) {
   EXPECT_EQ("bar", p2.second);
   ++iter;
   EXPECT_EQ(context.end(), iter);
-  // Range-based for loop test.
-  int i = 0;
-  for (auto p : context) {
-    switch (i++) {
-      case 0:
-        EXPECT_EQ("name", p.first);
-        EXPECT_EQ("chapi", p.second);
-        break;
-      case 1:
-        EXPECT_EQ("name", p.first);
-        EXPECT_EQ("chapo", p.second);
-        break;
-      case 2:
-        EXPECT_EQ("foo", p.first);
-        EXPECT_EQ("bar", p.second);
-        break;
-      default:
-        EXPECT_TRUE(0);
-    }
-  }
 }
 
 }  // namespace
diff --git a/test/cpp/end2end/async_end2end_test.cc b/test/cpp/end2end/async_end2end_test.cc
index 117d8bb9fa..b95bdf6b9b 100644
--- a/test/cpp/end2end/async_end2end_test.cc
+++ b/test/cpp/end2end/async_end2end_test.cc
@@ -415,7 +415,7 @@ TEST_F(AsyncEnd2endTest, ClientInitialMetadataRpc) {
   auto client_initial_metadata = srv_ctx.client_metadata();
   EXPECT_EQ(meta1.second, client_initial_metadata.find(meta1.first)->second);
   EXPECT_EQ(meta2.second, client_initial_metadata.find(meta2.first)->second);
-  EXPECT_EQ(static_cast<size_t>(2), client_initial_metadata.size());
+  EXPECT_GE(client_initial_metadata.size(), static_cast<size_t>(2));
 
   send_response.set_message(recv_request.message());
   response_writer.Finish(send_response, Status::OK, tag(3));
@@ -563,7 +563,7 @@ TEST_F(AsyncEnd2endTest, MetadataRpc) {
   auto client_initial_metadata = srv_ctx.client_metadata();
   EXPECT_EQ(meta1.second, client_initial_metadata.find(meta1.first)->second);
   EXPECT_EQ(meta2.second, client_initial_metadata.find(meta2.first)->second);
-  EXPECT_EQ(static_cast<size_t>(2), client_initial_metadata.size());
+  EXPECT_GE(client_initial_metadata.size(), static_cast<size_t>(2));
 
   srv_ctx.AddInitialMetadata(meta3.first, meta3.second);
   srv_ctx.AddInitialMetadata(meta4.first, meta4.second);
@@ -574,7 +574,7 @@ TEST_F(AsyncEnd2endTest, MetadataRpc) {
   auto server_initial_metadata = cli_ctx.GetServerInitialMetadata();
   EXPECT_EQ(meta3.second, server_initial_metadata.find(meta3.first)->second);
   EXPECT_EQ(meta4.second, server_initial_metadata.find(meta4.first)->second);
-  EXPECT_EQ(static_cast<size_t>(2), server_initial_metadata.size());
+  EXPECT_GE(server_initial_metadata.size(), static_cast<size_t>(2));
 
   send_response.set_message(recv_request.message());
   srv_ctx.AddTrailingMetadata(meta5.first, meta5.second);
@@ -590,7 +590,7 @@ TEST_F(AsyncEnd2endTest, MetadataRpc) {
   auto server_trailing_metadata = cli_ctx.GetServerTrailingMetadata();
   EXPECT_EQ(meta5.second, server_trailing_metadata.find(meta5.first)->second);
   EXPECT_EQ(meta6.second, server_trailing_metadata.find(meta6.first)->second);
-  EXPECT_EQ(static_cast<size_t>(2), server_trailing_metadata.size());
+  EXPECT_GE(server_trailing_metadata.size(), static_cast<size_t>(2));
 }
 }  // namespace
 }  // namespace testing
diff --git a/test/cpp/end2end/end2end_test.cc b/test/cpp/end2end/end2end_test.cc
index 6367bea092..20e4c4ed55 100644
--- a/test/cpp/end2end/end2end_test.cc
+++ b/test/cpp/end2end/end2end_test.cc
@@ -249,9 +249,10 @@ class End2endTest : public ::testing::Test {
   void TearDown() GRPC_OVERRIDE { server_->Shutdown(); }
 
   void ResetStub() {
-    std::shared_ptr<ChannelInterface> channel =
-        CreateChannel(server_address_.str(), FakeTransportSecurityCredentials(),
-                      ChannelArguments());
+    ChannelArguments args;
+    args.SetString(GRPC_ARG_SECONDARY_USER_AGENT_STRING, "end2end_test");
+    std::shared_ptr<ChannelInterface> channel = CreateChannel(
+        server_address_.str(), FakeTransportSecurityCredentials(), args);
     stub_ = std::move(grpc::cpp::test::util::TestService::NewStub(channel));
   }
 
@@ -273,7 +274,7 @@ static void SendRpc(grpc::cpp::test::util::TestService::Stub* stub,
 
   for (int i = 0; i < num_rpcs; ++i) {
     ClientContext context;
-    context._experimental_set_compression_algorithm(GRPC_COMPRESS_GZIP);
+    context.set_compression_algorithm(GRPC_COMPRESS_GZIP);
     Status s = stub->Echo(&context, request, &response);
     EXPECT_EQ(response.message(), request.message());
     EXPECT_TRUE(s.ok());
@@ -508,7 +509,7 @@ TEST_F(End2endTest, DiffPackageServices) {
 // rpc and stream should fail on bad credentials.
 TEST_F(End2endTest, BadCredentials) {
   std::shared_ptr<Credentials> bad_creds = ServiceAccountCredentials("", "", 1);
-  EXPECT_EQ(nullptr, bad_creds.get());
+  EXPECT_EQ(static_cast<Credentials *>(nullptr), bad_creds.get());
   std::shared_ptr<ChannelInterface> channel =
       CreateChannel(server_address_.str(), bad_creds, ChannelArguments());
   std::unique_ptr<grpc::cpp::test::util::TestService::Stub> stub(
diff --git a/test/cpp/end2end/generic_end2end_test.cc b/test/cpp/end2end/generic_end2end_test.cc
index 8fe0d6886a..4951c82b9a 100644
--- a/test/cpp/end2end/generic_end2end_test.cc
+++ b/test/cpp/end2end/generic_end2end_test.cc
@@ -227,7 +227,7 @@ TEST_F(GenericEnd2endTest, SimpleBidiStreaming) {
   GenericServerContext srv_ctx;
   GenericServerAsyncReaderWriter srv_stream(&srv_ctx);
 
-  cli_ctx._experimental_set_compression_algorithm(GRPC_COMPRESS_GZIP);
+  cli_ctx.set_compression_algorithm(GRPC_COMPRESS_GZIP);
   send_request.set_message("Hello");
   std::unique_ptr<GenericClientAsyncReaderWriter> cli_stream =
       generic_stub_->Call(&cli_ctx, kMethodName, &cli_cq_, tag(1));
diff --git a/test/cpp/interop/client.cc b/test/cpp/interop/client.cc
index 1f1e6c1306..d0393fafb2 100644
--- a/test/cpp/interop/client.cc
+++ b/test/cpp/interop/client.cc
@@ -69,6 +69,7 @@ DEFINE_string(test_case, "large_unary",
               "compute_engine_creds: large_unary with compute engine auth; "
               "jwt_token_creds: large_unary with JWT token auth; "
               "oauth2_auth_token: raw oauth2 access token auth; "
+              "per_rpc_creds: raw oauth2 access token on a single rpc; "
               "all : all of above.");
 DEFINE_string(default_service_account, "",
               "Email of GCE default service account");
@@ -117,6 +118,9 @@ int main(int argc, char** argv) {
   } else if (FLAGS_test_case == "oauth2_auth_token") {
     grpc::string json_key = GetServiceAccountJsonKey();
     client.DoOauth2AuthToken(json_key, FLAGS_oauth_scope);
+  } else if (FLAGS_test_case == "per_rpc_creds") {
+    grpc::string json_key = GetServiceAccountJsonKey();
+    client.DoPerRpcCreds(json_key, FLAGS_oauth_scope);
   } else if (FLAGS_test_case == "all") {
     client.DoEmpty();
     client.DoLargeUnary();
@@ -133,6 +137,7 @@ int main(int argc, char** argv) {
       client.DoServiceAccountCreds(json_key, FLAGS_oauth_scope);
       client.DoJwtTokenCreds(json_key);
       client.DoOauth2AuthToken(json_key, FLAGS_oauth_scope);
+      client.DoPerRpcCreds(json_key, FLAGS_oauth_scope);
     }
     // compute_engine_creds only runs in GCE.
   } else {
@@ -142,7 +147,7 @@ int main(int argc, char** argv) {
         "large_unary|client_streaming|server_streaming|half_duplex|ping_pong|"
         "cancel_after_begin|cancel_after_first_response|"
         "timeout_on_sleeping_server|service_account_creds|compute_engine_creds|"
-        "jwt_token_creds|oauth2_auth_token",
+        "jwt_token_creds|oauth2_auth_token|per_rpc_creds",
         FLAGS_test_case.c_str());
     ret = 1;
   }
diff --git a/test/cpp/interop/interop_client.cc b/test/cpp/interop/interop_client.cc
index 4dcd8ad061..e5c0e4631f 100644
--- a/test/cpp/interop/interop_client.cc
+++ b/test/cpp/interop/interop_client.cc
@@ -41,8 +41,10 @@
 #include <grpc/support/log.h>
 #include <grpc++/channel_interface.h>
 #include <grpc++/client_context.h>
+#include <grpc++/credentials.h>
 #include <grpc++/status.h>
 #include <grpc++/stream.h>
+#include "test/cpp/interop/client_helper.h"
 #include "test/proto/test.grpc.pb.h"
 #include "test/proto/empty.grpc.pb.h"
 #include "test/proto/messages.grpc.pb.h"
@@ -166,6 +168,32 @@ void InteropClient::DoOauth2AuthToken(const grpc::string& username,
   gpr_log(GPR_INFO, "Unary with oauth2 access token credentials done.");
 }
 
+void InteropClient::DoPerRpcCreds(const grpc::string& username,
+                                  const grpc::string& oauth_scope) {
+  gpr_log(GPR_INFO,
+          "Sending a unary rpc with per-rpc raw oauth2 access token ...");
+  SimpleRequest request;
+  SimpleResponse response;
+  request.set_fill_username(true);
+  request.set_fill_oauth_scope(true);
+  std::unique_ptr<TestService::Stub> stub(TestService::NewStub(channel_));
+
+  ClientContext context;
+  grpc::string access_token = GetOauth2AccessToken();
+  std::shared_ptr<Credentials> creds = AccessTokenCredentials(access_token);
+  context.set_credentials(creds);
+
+  Status s = stub->UnaryCall(&context, request, &response);
+
+  AssertOkOrPrintErrorStatus(s);
+  GPR_ASSERT(!response.username().empty());
+  GPR_ASSERT(!response.oauth_scope().empty());
+  GPR_ASSERT(username.find(response.username()) != grpc::string::npos);
+  const char* oauth_scope_str = response.oauth_scope().c_str();
+  GPR_ASSERT(oauth_scope.find(oauth_scope_str) != grpc::string::npos);
+  gpr_log(GPR_INFO, "Unary with per-rpc oauth2 access token done.");
+}
+
 void InteropClient::DoJwtTokenCreds(const grpc::string& username) {
   gpr_log(GPR_INFO, "Sending a large unary rpc with JWT token credentials ...");
   SimpleRequest request;
diff --git a/test/cpp/interop/interop_client.h b/test/cpp/interop/interop_client.h
index 67eecd9ccc..bf8188325e 100644
--- a/test/cpp/interop/interop_client.h
+++ b/test/cpp/interop/interop_client.h
@@ -71,6 +71,9 @@ class InteropClient {
   // username is a string containing the user email
   void DoOauth2AuthToken(const grpc::string& username,
                          const grpc::string& oauth_scope);
+  // username is a string containing the user email
+  void DoPerRpcCreds(const grpc::string& username,
+                     const grpc::string& oauth_scope);
 
  private:
   void PerformLargeUnary(SimpleRequest* request, SimpleResponse* response);
diff --git a/test/cpp/qps/qps_test.cc b/test/cpp/qps/qps_test.cc
index 07b4834cc0..7b93443f7c 100644
--- a/test/cpp/qps/qps_test.cc
+++ b/test/cpp/qps/qps_test.cc
@@ -44,8 +44,8 @@
 namespace grpc {
 namespace testing {
 
-static const int WARMUP = 5;
-static const int BENCHMARK = 10;
+static const int WARMUP = 20;
+static const int BENCHMARK = 40;
 
 static void RunQPS() {
   gpr_log(GPR_INFO, "Running QPS test");
@@ -53,8 +53,8 @@ static void RunQPS() {
   ClientConfig client_config;
   client_config.set_client_type(ASYNC_CLIENT);
   client_config.set_enable_ssl(false);
-  client_config.set_outstanding_rpcs_per_channel(1000);
-  client_config.set_client_channels(8);
+  client_config.set_outstanding_rpcs_per_channel(10);
+  client_config.set_client_channels(800);
   client_config.set_payload_size(1);
   client_config.set_async_client_threads(8);
   client_config.set_rpc_type(UNARY);
@@ -62,7 +62,7 @@ static void RunQPS() {
   ServerConfig server_config;
   server_config.set_server_type(ASYNC_SERVER);
   server_config.set_enable_ssl(false);
-  server_config.set_threads(4);
+  server_config.set_threads(8);
 
   const auto result =
       RunScenario(client_config, 1, server_config, 1, WARMUP, BENCHMARK, -2);
diff --git a/tools/jenkins/docker_run_jenkins.sh b/tools/jenkins/docker_run_jenkins.sh
index eb6c9144c6..0a5516c30d 100755
--- a/tools/jenkins/docker_run_jenkins.sh
+++ b/tools/jenkins/docker_run_jenkins.sh
@@ -41,5 +41,5 @@ git clone --recursive /var/local/jenkins/grpc /var/local/git/grpc
 cd /var/local/git/grpc
 nvm use 0.12
 rvm use ruby-2.1
-tools/run_tests/prepare_travis.sh
-$arch tools/run_tests/run_tests.py -t -c $config -l $language -x report.xml
+
+setarch $arch tools/run_tests/run_tests.py -t -c $config -l $language -x report.xml
diff --git a/tools/jenkins/grpc_jenkins_slave/Dockerfile b/tools/jenkins/grpc_jenkins_slave/Dockerfile
index f37c0b9103..9058b0498e 100644
--- a/tools/jenkins/grpc_jenkins_slave/Dockerfile
+++ b/tools/jenkins/grpc_jenkins_slave/Dockerfile
@@ -38,8 +38,10 @@ RUN apt-get update && apt-get install -y \
   autotools-dev \
   build-essential \
   bzip2 \
+  ccache \
   curl \
   gcc \
+  gcc-multilib \
   git \
   libc6 \
   libc6-dbg \
@@ -55,6 +57,14 @@ RUN apt-get update && apt-get install -y \
   wget \
   zip && apt-get clean
 
+# Prepare ccache
+RUN ln -s /usr/bin/ccache /usr/local/bin/gcc
+RUN ln -s /usr/bin/ccache /usr/local/bin/g++
+RUN ln -s /usr/bin/ccache /usr/local/bin/cc
+RUN ln -s /usr/bin/ccache /usr/local/bin/c++
+RUN ln -s /usr/bin/ccache /usr/local/bin/clang
+RUN ln -s /usr/bin/ccache /usr/local/bin/clang++
+
 ##################
 # C++ dependencies
 RUN apt-get update && apt-get -y install libgflags-dev libgtest-dev libc++-dev clang
diff --git a/tools/jenkins/grpc_jenkins_slave_32bits/Dockerfile b/tools/jenkins/grpc_jenkins_slave_32bits/Dockerfile
new file mode 100644
index 0000000000..2beaf9a820
--- /dev/null
+++ b/tools/jenkins/grpc_jenkins_slave_32bits/Dockerfile
@@ -0,0 +1,152 @@
+# 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.
+
+# A work-in-progress Dockerfile that allows running gRPC test suites
+# inside a docker container.
+
+FROM 32bit/debian:jessie
+
+# Install Git.
+RUN apt-get update && apt-get install -y \
+  autoconf \
+  autotools-dev \
+  build-essential \
+  bzip2 \
+  ccache \
+  curl \
+  gcc \
+  gcc-multilib \
+  git \
+  libc6 \
+  libc6-dbg \
+  libc6-dev \
+  libgtest-dev \
+  libtool \
+  make \
+  strace \
+  python-dev \
+  python-setuptools \
+  telnet \
+  unzip \
+  wget \
+  zip && apt-get clean
+
+# Prepare ccache
+RUN ln -s /usr/bin/ccache /usr/local/bin/gcc
+RUN ln -s /usr/bin/ccache /usr/local/bin/g++
+RUN ln -s /usr/bin/ccache /usr/local/bin/cc
+RUN ln -s /usr/bin/ccache /usr/local/bin/c++
+RUN ln -s /usr/bin/ccache /usr/local/bin/clang
+RUN ln -s /usr/bin/ccache /usr/local/bin/clang++
+
+##################
+# C++ dependencies
+RUN apt-get update && apt-get -y install libgflags-dev libgtest-dev libc++-dev clang
+
+#################
+# C# dependencies
+
+# Update to a newer version of mono
+RUN apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF
+RUN echo "deb http://download.mono-project.com/repo/debian wheezy main" | tee /etc/apt/sources.list.d/mono-xamarin.list
+RUN echo "deb http://download.mono-project.com/repo/debian wheezy-apache24-compat main" | tee -a /etc/apt/sources.list.d/mono-xamarin.list
+RUN echo "deb http://download.mono-project.com/repo/debian wheezy-libjpeg62-compat main" | tee -a /etc/apt/sources.list.d/mono-xamarin.list
+RUN echo "deb http://download.mono-project.com/repo/debian wheezy-libtiff-compat main" | tee -a /etc/apt/sources.list.d/mono-xamarin.list
+
+# Install dependencies
+RUN apt-get update && apt-get -y dist-upgrade && apt-get install -y \
+    mono-devel \
+    nunit \
+    nunit-console \
+    monodevelop
+
+# Download NuGet
+RUN cd /var/local && wget www.nuget.org/NuGet.exe
+ENV NUGET mono /var/local/NuGet.exe
+
+# TODO(jtattermusch): add dependencies for other languages
+
+##################
+# Node dependencies
+
+# Install nvm
+RUN touch .profile
+RUN curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.25.4/install.sh | bash
+RUN /bin/bash -l -c "nvm install 0.12"
+
+##################
+# Ruby dependencies
+
+# Install rvm
+RUN gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3
+RUN \curl -sSL https://get.rvm.io | bash -s stable
+
+# Install Ruby 2.1
+RUN /bin/bash -l -c "rvm install ruby-2.1"
+RUN /bin/bash -l -c "rvm use --default ruby-2.1"
+RUN /bin/bash -l -c "echo 'gem: --no-ri --no-rdoc' > ~/.gemrc"
+RUN /bin/bash -l -c "echo 'export PATH=/usr/local/rvm/bin:$PATH' >> ~/.bashrc"
+RUN /bin/bash -l -c "echo 'rvm --default use ruby-2.1' >> ~/.bashrc"
+RUN /bin/bash -l -c "gem install bundler --no-ri --no-rdoc"
+
+##################
+# Python dependencies
+
+# Install dependencies
+
+RUN apt-get update && apt-get install -y \
+    python-all-dev \
+    python3-all-dev \
+    python-pip \
+    python-virtualenv
+
+# Install Python packages from PyPI
+RUN pip install futures==2.2.0 enum34==1.0.4 protobuf==3.0.0a2
+
+# For sanity test
+RUN pip install simplejson mako
+
+##################
+# PHP dependencies
+
+# Install dependencies
+
+RUN /bin/bash -l -c "echo 'deb http://packages.dotdeb.org wheezy-php55 all' \
+    >> /etc/apt/sources.list.d/dotdeb.list"
+RUN /bin/bash -l -c "echo 'deb-src http://packages.dotdeb.org wheezy-php55 all' \
+    >> /etc/apt/sources.list.d/dotdeb.list"
+RUN wget http://www.dotdeb.org/dotdeb.gpg -O- | apt-key add -
+
+RUN apt-get update && apt-get install -y \
+    git php5 php5-dev phpunit unzip
+
+RUN mkdir /var/local/jenkins
+
+# Define the default command.
+CMD ["bash"]
diff --git a/tools/jenkins/grpc_linuxbrew/Dockerfile b/tools/jenkins/grpc_linuxbrew/Dockerfile
index 9b76e3cea0..848489e091 100644
--- a/tools/jenkins/grpc_linuxbrew/Dockerfile
+++ b/tools/jenkins/grpc_linuxbrew/Dockerfile
@@ -55,7 +55,7 @@ RUN /bin/bash -l -c "\curl -sSL https://get.rvm.io | bash -s stable"
 RUN /bin/bash -l -c "rvm install ruby-2.1"
 
 # PHP dependency
-RUN apt-get update && apt-get install -y php5 php5-dev phpunit unzip
+RUN apt-get update && apt-get install -y php5 php5-dev php-pear phpunit unzip
 
 RUN /bin/bash -l -c "echo 'export PATH=/home/linuxbrew/.linuxbrew/bin:\$PATH' >> ~/.bashrc"
 
diff --git a/tools/jenkins/run_distribution.sh b/tools/jenkins/run_distribution.sh
index 10c41b4099..7c306de590 100755
--- a/tools/jenkins/run_distribution.sh
+++ b/tools/jenkins/run_distribution.sh
@@ -32,24 +32,117 @@
 # linuxbrew installation of a selected language
 set -ex
 
-sha1=$(sha1sum tools/jenkins/grpc_linuxbrew/Dockerfile | cut -f1 -d\ )
-DOCKER_IMAGE_NAME=grpc_linuxbrew_$sha1
-
-docker build -t $DOCKER_IMAGE_NAME tools/jenkins/grpc_linuxbrew
-
-supported="python nodejs ruby php"
-
 if [ "$language" == "core" ]; then
   command="curl -fsSL https://goo.gl/getgrpc | bash -"
-elif [[ "$supported" =~ "$language" ]]; then
+elif [[ "python nodejs ruby php" =~ "$language" ]]; then
   command="curl -fsSL https://goo.gl/getgrpc | bash -s $language"
 else
   echo "unsupported language $language"
   exit 1
 fi
 
-docker run $DOCKER_IMAGE_NAME bash -l \
-  -c "nvm use 0.12; \
-      npm set unsafe-perm true; \
-      rvm use ruby-2.1; \
-      $command"
+if [ "$platform" == "linux" ]; then
+
+  if [ "$dist_channel" == "homebrew" ]; then
+
+    sha1=$(sha1sum tools/jenkins/grpc_linuxbrew/Dockerfile | cut -f1 -d\ )
+    DOCKER_IMAGE_NAME=grpc_linuxbrew_$sha1
+
+    # build docker image, contains all pre-requisites
+    docker build -t $DOCKER_IMAGE_NAME tools/jenkins/grpc_linuxbrew
+
+    # run per-language homebrew installation script
+    docker run $DOCKER_IMAGE_NAME bash -l \
+      -c "nvm use 0.12; \
+          npm set unsafe-perm true; \
+          rvm use ruby-2.1; \
+          $command"
+
+  else
+    echo "Unsupported $platform dist_channel $dist_channel"
+    exit 1
+  fi
+
+elif [ "$platform" == "macos" ]; then
+
+  if [ "$dist_channel" == "homebrew" ]; then
+    echo "Formulas installed by system-wide homebrew (before)"
+    brew list -l
+
+    # Save the original PATH so that we can run the system `brew` command
+    # again at the end of the script
+    export ORIGINAL_PATH=$PATH
+
+    # Set up temp directories for test installation of homebrew
+    brew_root=/tmp/homebrew-test-$language
+    rm -rf $brew_root
+    mkdir -p $brew_root
+    git clone https://github.com/Homebrew/homebrew.git $brew_root
+
+    # Make sure we are operating at the right copy of temp homebrew
+    # installation
+    export PATH=$brew_root/bin:$PATH
+
+    # Set up right environment for each language
+    case $language in
+      *python*)
+        rm -rf jenkins_python_venv
+        virtualenv jenkins_python_venv
+        source jenkins_python_venv/bin/activate
+        ;;
+      *nodejs*)
+        export PATH=$HOME/.nvm/versions/node/v0.12.7/bin:$PATH
+        ;;
+      *ruby*)
+        export PATH=/usr/local/rvm/rubies/ruby-2.2.1/bin:$PATH
+        ;;
+      *php*)
+        export CFLAGS="-Wno-parentheses-equality"
+        ;;
+      *)
+        ;;
+    esac
+
+    # Run our homebrew installation script
+    bash -c "$command"
+
+    # Uninstall / clean up per-language modules/extensions after the test
+    case $language in
+      *core*) ;;
+      *python*)
+        deactivate
+        rm -rf jenkins_python_venv
+        ;;
+      *nodejs*)
+        npm list -g | grep grpc
+        npm uninstall -g grpc
+        ;;
+      *ruby*)
+        gem list | grep grpc
+        gem uninstall grpc
+        ;;
+      *php*)
+        rm grpc.so
+        ;;
+      *)
+        echo "Unsupported language $language"
+        exit 1
+        ;;
+    esac
+
+    # Clean up
+    rm -rf $brew_root
+
+    echo "Formulas installed by system-wide homebrew (after, should be unaffected)"
+    export PATH=$ORIGINAL_PATH
+    brew list -l
+
+  else
+    echo "Unsupported $platform dist_channel $dist_channel"
+    exit 1
+  fi
+
+else
+  echo "unsupported platform $platform"
+  exit 1
+fi
diff --git a/tools/jenkins/run_jenkins.sh b/tools/jenkins/run_jenkins.sh
index 8cb85cb12b..56f9e82ca5 100755
--- a/tools/jenkins/run_jenkins.sh
+++ b/tools/jenkins/run_jenkins.sh
@@ -46,6 +46,7 @@ case $platform in
   i386)
     arch="i386"
     platform="linux"
+    docker_suffix=_32bits
     ;;
 esac
 
@@ -57,11 +58,13 @@ then
   git_root=`pwd`
   cd -
 
+  mkdir -p /tmp/ccache
+
   # Use image name based on Dockerfile checksum
-  DOCKER_IMAGE_NAME=grpc_jenkins_slave_`sha1sum tools/jenkins/grpc_jenkins_slave/Dockerfile | cut -f1 -d\ `
+  DOCKER_IMAGE_NAME=grpc_jenkins_slave$docker_suffix_`sha1sum tools/jenkins/grpc_jenkins_slave/Dockerfile | cut -f1 -d\ `
 
   # Make sure docker image has been built. Should be instantaneous if so.
-  docker build -t $DOCKER_IMAGE_NAME tools/jenkins/grpc_jenkins_slave
+  docker build -t $DOCKER_IMAGE_NAME tools/jenkins/grpc_jenkins_slave$docker_suffix
 
   # Create a local branch so the child Docker script won't complain
   git branch jenkins-docker
@@ -74,8 +77,10 @@ then
     -e "config=$config" \
     -e "language=$language" \
     -e "arch=$arch" \
+    -e CCACHE_DIR=/tmp/ccache \
     -i \
     -v "$git_root:/var/local/jenkins/grpc" \
+    -v /tmp/ccache:/tmp/ccache \
     --cidfile=docker.cid \
     $DOCKER_IMAGE_NAME \
     bash -l /var/local/jenkins/grpc/tools/jenkins/docker_run_jenkins.sh || DOCKER_FAILED="true"