diff --git a/doc/qbk/03_core/_core.qbk b/doc/qbk/03_core/_core.qbk
index 2a55c7d2..5fee997f 100644
--- a/doc/qbk/03_core/_core.qbk
+++ b/doc/qbk/03_core/_core.qbk
@@ -15,8 +15,8 @@ scheduled to become an official part of C++ no sooner than the year
 2023. Three implementations exist, with cosmetic differences but
 otherwise using the same function signatures and type declarations:
 Boost.Asio, stand-alone Asio, and networking-ts-impl. This table shows
-how a variable of the each library's `io_context` type is declared by
-including the appropriate header and using a suitable namespace alias:
+how a variable of type `io_context` is declared in each implementation
+by including the appropriate header and using a suitable namespace alias:
 
 [table Networking Implementations
 [[Name][Namespace and Header Example ]]
diff --git a/doc/qbk/main.qbk b/doc/qbk/main.qbk
index e52a909a..e0774a33 100644
--- a/doc/qbk/main.qbk
+++ b/doc/qbk/main.qbk
@@ -87,6 +87,7 @@
 [def __Body__                   [link beast.concepts.Body ['Body]]]
 [def __BodyReader__             [link beast.concepts.BodyReader ['BodyReader]]]
 [def __BodyWriter__             [link beast.concepts.BodyWriter ['BodyWriter]]]
+[def __BufferSequence__         [link beast.concepts.BufferSequence ['BufferSequence]]]
 [def __DynamicBuffer__          [link beast.concepts.DynamicBuffer ['DynamicBuffer]]]
 [def __Fields__                 [link beast.concepts.Fields ['Fields]]]
 [def __FieldsWriter__           [link beast.concepts.FieldsWriter ['FieldsWriter]]]
diff --git a/doc/source.dox b/doc/source.dox
index d5ecd7c4..d43103fc 100644
--- a/doc/source.dox
+++ b/doc/source.dox
@@ -1,3 +1,57 @@
+#---------------------------------------------------------------------------
+# Configuration options related to the input files
+#---------------------------------------------------------------------------
+INPUT = \
+        $(LIB_DIR)/include/boost/beast/ \
+        $(LIB_DIR)/include/boost/beast/_experimental/http \
+        $(LIB_DIR)/include/boost/beast/_experimental/test \
+        $(LIB_DIR)/include/boost/beast/core \
+        $(LIB_DIR)/include/boost/beast/http \
+        $(LIB_DIR)/include/boost/beast/ssl \
+        $(LIB_DIR)/include/boost/beast/websocket \
+        $(LIB_DIR)/include/boost/beast/zlib
+
+
+INPUT_ENCODING         = UTF-8
+FILE_PATTERNS          =
+RECURSIVE              = NO
+EXCLUDE                =
+EXCLUDE_SYMLINKS       = NO
+EXCLUDE_PATTERNS       =
+EXCLUDE_SYMBOLS        =
+EXAMPLE_PATH           =
+EXAMPLE_PATTERNS       =
+EXAMPLE_RECURSIVE      = NO
+IMAGE_PATH             =
+INPUT_FILTER           =
+FILTER_PATTERNS        =
+FILTER_SOURCE_FILES    = NO
+FILTER_SOURCE_PATTERNS =
+USE_MDFILE_AS_MAINPAGE =
+
+#---------------------------------------------------------------------------
+# Configuration options related to the preprocessor
+#---------------------------------------------------------------------------
+ENABLE_PREPROCESSING   = YES
+MACRO_EXPANSION        = YES
+EXPAND_ONLY_PREDEF     = YES
+SEARCH_INCLUDES        = YES
+INCLUDE_PATH           = ../
+INCLUDE_FILE_PATTERNS  =
+
+PREDEFINED             = \
+                        BOOST_BEAST_DOXYGEN \
+                        BOOST_BEAST_USE_POSIX_FILE=1 \
+                        BOOST_BEAST_USE_WIN32_FILE=1 \
+                        BOOST_BEAST_SPLIT_COMPILATION=1 \
+                        BOOST_BEAST_ASYNC_RESULT1(t)=__deduced__ \
+                        BOOST_BEAST_ASYNC_RESULT1(t)=__deduced__ \
+                        BOOST_ASIO_INITFN_RESULT_TYPE(t,a)=__deduced__ \
+                        GENERATING_DOCUMENTATION \
+                        BOOST_BEAST_DECL
+EXPAND_AS_DEFINED      =
+SKIP_FUNCTION_MACROS   = YES
+
 #---------------------------------------------------------------------------
 # Project related configuration options
 #---------------------------------------------------------------------------
@@ -99,37 +153,6 @@ WARN_NO_PARAMDOC       = NO
 WARN_FORMAT            = "$file:$line: $text"
 WARN_LOGFILE           =
 
-#---------------------------------------------------------------------------
-# Configuration options related to the input files
-#---------------------------------------------------------------------------
-INPUT = \
-        $(LIB_DIR)/include/boost/beast/ \
-        $(LIB_DIR)/include/boost/beast/_experimental/http \
-        $(LIB_DIR)/include/boost/beast/_experimental/test \
-        $(LIB_DIR)/include/boost/beast/core \
-        $(LIB_DIR)/include/boost/beast/http \
-        $(LIB_DIR)/include/boost/beast/ssl \
-        $(LIB_DIR)/include/boost/beast/websocket \
-        $(LIB_DIR)/include/boost/beast/zlib
-
-
-INPUT_ENCODING         = UTF-8
-FILE_PATTERNS          =
-RECURSIVE              = NO
-EXCLUDE                =
-EXCLUDE_SYMLINKS       = NO
-EXCLUDE_PATTERNS       =
-EXCLUDE_SYMBOLS        =
-EXAMPLE_PATH           =
-EXAMPLE_PATTERNS       =
-EXAMPLE_RECURSIVE      = NO
-IMAGE_PATH             =
-INPUT_FILTER           =
-FILTER_PATTERNS        =
-FILTER_SOURCE_FILES    = NO
-FILTER_SOURCE_PATTERNS =
-USE_MDFILE_AS_MAINPAGE =
-
 #---------------------------------------------------------------------------
 # Configuration options related to source browsing
 #---------------------------------------------------------------------------
@@ -227,27 +250,6 @@ GENERATE_XML           = YES
 XML_OUTPUT             = $(XML_OUTPUT)
 XML_PROGRAMLISTING     = YES
 
-#---------------------------------------------------------------------------
-# Configuration options related to the preprocessor
-#---------------------------------------------------------------------------
-ENABLE_PREPROCESSING   = YES
-MACRO_EXPANSION        = YES
-EXPAND_ONLY_PREDEF     = YES
-SEARCH_INCLUDES        = YES
-INCLUDE_PATH           = ../
-INCLUDE_FILE_PATTERNS  =
-
-PREDEFINED             = \
-                        BOOST_BEAST_DOXYGEN \
-                        BOOST_BEAST_USE_POSIX_FILE=1 \
-                        BOOST_BEAST_USE_WIN32_FILE=1 \
-                        BOOST_BEAST_SPLIT_COMPILATION=1 \
-                        BOOST_ASIO_INITFN_RESULT_TYPE(t,a)=__deduced__ \
-                        GENERATING_DOCUMENTATION \
-                        BOOST_BEAST_DECL
-EXPAND_AS_DEFINED      =
-SKIP_FUNCTION_MACROS   = YES
-
 #---------------------------------------------------------------------------
 # Configuration options related to external references
 #---------------------------------------------------------------------------
diff --git a/include/boost/beast.hpp b/include/boost/beast.hpp
index f2d74ed8..458f20a7 100644
--- a/include/boost/beast.hpp
+++ b/include/boost/beast.hpp
@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2013-2017 Vinnie Falco (vinnie dot falco at gmail dot com)
+// Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
 //
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
diff --git a/include/boost/beast/_experimental/http/icy_stream.hpp b/include/boost/beast/_experimental/http/icy_stream.hpp
index 2eb0c6e1..e546bdd0 100644
--- a/include/boost/beast/_experimental/http/icy_stream.hpp
+++ b/include/boost/beast/_experimental/http/icy_stream.hpp
@@ -227,8 +227,7 @@ public:
     template<
         class MutableBufferSequence,
         class ReadHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        ReadHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
     async_read_some(
         MutableBufferSequence const& buffers,
         ReadHandler&& handler);
@@ -309,8 +308,7 @@ public:
     template<
         class ConstBufferSequence,
         class WriteHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
     async_write_some(
         ConstBufferSequence const& buffers,
         WriteHandler&& handler);
diff --git a/include/boost/beast/_experimental/http/impl/icy_stream.hpp b/include/boost/beast/_experimental/http/impl/icy_stream.hpp
index 3879dd5c..8e9a46b8 100644
--- a/include/boost/beast/_experimental/http/impl/icy_stream.hpp
+++ b/include/boost/beast/_experimental/http/impl/icy_stream.hpp
@@ -473,8 +473,7 @@ template<class NextLayer>
 template<
     class MutableBufferSequence,
     class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 icy_stream<NextLayer>::
 async_read_some(
     MutableBufferSequence const& buffers,
@@ -526,8 +525,7 @@ template<class NextLayer>
 template<
     class MutableBufferSequence,
     class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 icy_stream<NextLayer>::
 async_write_some(
     MutableBufferSequence const& buffers,
diff --git a/include/boost/beast/_experimental/test/impl/stream.hpp b/include/boost/beast/_experimental/test/impl/stream.hpp
index 3cc5dfce..c117bbbd 100644
--- a/include/boost/beast/_experimental/test/impl/stream.hpp
+++ b/include/boost/beast/_experimental/test/impl/stream.hpp
@@ -304,8 +304,7 @@ read_some(MutableBufferSequence const& buffers,
 }
 
 template<class MutableBufferSequence, class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 stream::
 async_read_some(
     MutableBufferSequence const& buffers,
@@ -384,8 +383,7 @@ write_some(
 }
 
 template<class ConstBufferSequence, class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 stream::
 async_write_some(
     ConstBufferSequence const& buffers,
diff --git a/include/boost/beast/_experimental/test/stream.hpp b/include/boost/beast/_experimental/test/stream.hpp
index 7eb71ba7..37f7df0f 100644
--- a/include/boost/beast/_experimental/test/stream.hpp
+++ b/include/boost/beast/_experimental/test/stream.hpp
@@ -431,8 +431,7 @@ public:
         operation completes.
     */
     template<class MutableBufferSequence, class ReadHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        ReadHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
     async_read_some(MutableBufferSequence const& buffers,
         ReadHandler&& handler);
 
@@ -509,8 +508,7 @@ public:
         to ensure that all data is written before the asynchronous operation completes.
     */
     template<class ConstBufferSequence, class WriteHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
     async_write_some(ConstBufferSequence const& buffers,
         WriteHandler&& handler);
 
diff --git a/include/boost/beast/core/async_base.hpp b/include/boost/beast/core/async_base.hpp
index a301ccc2..10c2f3c5 100644
--- a/include/boost/beast/core/async_base.hpp
+++ b/include/boost/beast/core/async_base.hpp
@@ -78,7 +78,7 @@ namespace beast {
 
     // Asynchronously read into a buffer until the buffer is full, or an error occurs
     template<class AsyncReadStream, class ReadHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler, void (error_code, std::size_t))
+    typename net::async_result<ReadHandler, void(error_code, std::size_t)>::return_type
     async_read(AsyncReadStream& stream, net::mutable_buffer buffer, ReadHandler&& handler)
     {
         using handler_type = BOOST_ASIO_HANDLER_TYPE(ReadHandler, void(error_code, std::size_t));
diff --git a/include/boost/beast/core/basic_stream.hpp b/include/boost/beast/core/basic_stream.hpp
index 9f2dcfc1..a44fabd8 100644
--- a/include/boost/beast/core/basic_stream.hpp
+++ b/include/boost/beast/core/basic_stream.hpp
@@ -905,8 +905,7 @@ public:
         @see @ref async_connect
     */
     template<class ConnectHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(ConnectHandler,
-        void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(ConnectHandler)
     async_connect(
         endpoint_type const& ep,
         ConnectHandler&& handler);
@@ -963,8 +962,7 @@ public:
                 EndpointSequence>::value>::type
     #endif
     >
-    BOOST_ASIO_INITFN_RESULT_TYPE(RangeConnectHandler,
-        void (error_code, typename Protocol::endpoint))
+    BOOST_ASIO_INITFN_RESULT_TYPE(RangeConnectHandler,void (error_code, typename Protocol::endpoint))
     async_connect(
         EndpointSequence const& endpoints,
         RangeConnectHandler&& handler);
@@ -1053,8 +1051,7 @@ public:
                 EndpointSequence>::value>::type
     #endif
     >
-    BOOST_ASIO_INITFN_RESULT_TYPE(RangeConnectHandler,
-        void (error_code, typename Protocol::endpoint))
+    BOOST_ASIO_INITFN_RESULT_TYPE(RangeConnectHandler,void (error_code, typename Protocol::endpoint))
     async_connect(
         EndpointSequence const& endpoints,
         ConnectCondition connect_condition,
@@ -1107,8 +1104,7 @@ public:
     template<
         class Iterator,
         class IteratorConnectHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(IteratorConnectHandler,
-        void (error_code, Iterator))
+    BOOST_ASIO_INITFN_RESULT_TYPE(IteratorConnectHandler,void (error_code, Iterator))
     async_connect(
         Iterator begin, Iterator end,
         IteratorConnectHandler&& handler);
@@ -1165,8 +1161,7 @@ public:
         class Iterator,
         class ConnectCondition,
         class IteratorConnectHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(IteratorConnectHandler,
-        void (error_code, Iterator))
+    BOOST_ASIO_INITFN_RESULT_TYPE(IteratorConnectHandler,void (error_code, Iterator))
     async_connect(
         Iterator begin, Iterator end,
         ConnectCondition connect_condition,
@@ -1286,8 +1281,7 @@ public:
         operation completes.
     */
     template<class MutableBufferSequence, class ReadHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
-        void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
     async_read_some(
         MutableBufferSequence const& buffers,
         ReadHandler&& handler);
@@ -1406,8 +1400,7 @@ public:
         operation completes.
     */
     template<class ConstBufferSequence, class WriteHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
-        void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
     async_write_some(
         ConstBufferSequence const& buffers,
         WriteHandler&& handler);
diff --git a/include/boost/beast/core/buffered_read_stream.hpp b/include/boost/beast/core/buffered_read_stream.hpp
index 7dd23acd..f588f6e4 100644
--- a/include/boost/beast/core/buffered_read_stream.hpp
+++ b/include/boost/beast/core/buffered_read_stream.hpp
@@ -264,8 +264,7 @@ public:
         manner equivalent to using `net::post`.
     */
     template<class MutableBufferSequence, class ReadHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        ReadHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
     async_read_some(MutableBufferSequence const& buffers,
         ReadHandler&& handler);
 
@@ -341,8 +340,7 @@ public:
         manner equivalent to using `net::post`.
     */
     template<class ConstBufferSequence, class WriteHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
     async_write_some(ConstBufferSequence const& buffers,
         WriteHandler&& handler);
 };
diff --git a/include/boost/beast/core/detail/config.hpp b/include/boost/beast/core/detail/config.hpp
index a3ef7f78..67c614af 100644
--- a/include/boost/beast/core/detail/config.hpp
+++ b/include/boost/beast/core/detail/config.hpp
@@ -83,4 +83,14 @@ namespace net = boost::asio;
 # define BOOST_BEAST_DECL
 #endif
 
+#ifndef BOOST_BEAST_ASYNC_RESULT1
+#define BOOST_BEAST_ASYNC_RESULT1(type) \
+    BOOST_ASIO_INITFN_RESULT_TYPE(type, void(::boost::beast::error_code))
+#endif
+
+#ifndef BOOST_BEAST_ASYNC_RESULT2
+#define BOOST_BEAST_ASYNC_RESULT2(type) \
+    BOOST_ASIO_INITFN_RESULT_TYPE(type, void(::boost::beast::error_code, std::size_t))
+#endif
+
 #endif
diff --git a/include/boost/beast/core/detail/impl/read.hpp b/include/boost/beast/core/detail/impl/read.hpp
index 74458ed2..2acee883 100644
--- a/include/boost/beast/core/detail/impl/read.hpp
+++ b/include/boost/beast/core/detail/impl/read.hpp
@@ -227,8 +227,7 @@ template<
     class CompletionCondition,
     class ReadHandler,
     class>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 async_read(
     AsyncReadStream& stream,
     DynamicBuffer& buffer,
diff --git a/include/boost/beast/core/detail/read.hpp b/include/boost/beast/core/detail/read.hpp
index 6ff2198b..7d8d03cc 100644
--- a/include/boost/beast/core/detail/read.hpp
+++ b/include/boost/beast/core/detail/read.hpp
@@ -231,8 +231,7 @@ template<
     >::type
 #endif
 >
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 async_read(
     AsyncReadStream& stream,
     DynamicBuffer& buffer,
diff --git a/include/boost/beast/core/file.hpp b/include/boost/beast/core/file.hpp
index bb1ed7bc..f0b530ae 100644
--- a/include/boost/beast/core/file.hpp
+++ b/include/boost/beast/core/file.hpp
@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2015-2016 Vinnie Falco (vinnie dot falco at gmail dot com)
+// Copyright (c) 2015-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
 //
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
diff --git a/include/boost/beast/core/file_base.hpp b/include/boost/beast/core/file_base.hpp
index 9229aa7a..e49c5194 100644
--- a/include/boost/beast/core/file_base.hpp
+++ b/include/boost/beast/core/file_base.hpp
@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2015-2016 Vinnie Falco (vinnie dot falco at gmail dot com)
+// Copyright (c) 2015-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
 //
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
diff --git a/include/boost/beast/core/file_posix.hpp b/include/boost/beast/core/file_posix.hpp
index 86e53523..313e0978 100644
--- a/include/boost/beast/core/file_posix.hpp
+++ b/include/boost/beast/core/file_posix.hpp
@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2015-2016 Vinnie Falco (vinnie dot falco at gmail dot com)
+// Copyright (c) 2015-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
 //
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
diff --git a/include/boost/beast/core/file_stdio.hpp b/include/boost/beast/core/file_stdio.hpp
index 860c1e5e..d56632b8 100644
--- a/include/boost/beast/core/file_stdio.hpp
+++ b/include/boost/beast/core/file_stdio.hpp
@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2015-2016 Vinnie Falco (vinnie dot falco at gmail dot com)
+// Copyright (c) 2015-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
 //
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
diff --git a/include/boost/beast/core/file_win32.hpp b/include/boost/beast/core/file_win32.hpp
index 4cdc312e..61246c43 100644
--- a/include/boost/beast/core/file_win32.hpp
+++ b/include/boost/beast/core/file_win32.hpp
@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2015-2016 Vinnie Falco (vinnie dot falco at gmail dot com)
+// Copyright (c) 2015-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
 //
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
diff --git a/include/boost/beast/core/flat_stream.hpp b/include/boost/beast/core/flat_stream.hpp
index 958e9265..288eaf2c 100644
--- a/include/boost/beast/core/flat_stream.hpp
+++ b/include/boost/beast/core/flat_stream.hpp
@@ -256,8 +256,7 @@ public:
     template<
         class MutableBufferSequence,
         class ReadHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        ReadHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
     async_read_some(
         MutableBufferSequence const& buffers,
         ReadHandler&& handler);
@@ -338,8 +337,7 @@ public:
     template<
         class ConstBufferSequence,
         class WriteHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
     async_write_some(
         ConstBufferSequence const& buffers,
         WriteHandler&& handler);
diff --git a/include/boost/beast/core/impl/basic_stream.hpp b/include/boost/beast/core/impl/basic_stream.hpp
index 214907d5..0a1f3635 100644
--- a/include/boost/beast/core/impl/basic_stream.hpp
+++ b/include/boost/beast/core/impl/basic_stream.hpp
@@ -801,8 +801,7 @@ close()
 
 template<class Protocol, class Executor, class RatePolicy>
 template<class ConnectHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(ConnectHandler,
-    void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(ConnectHandler)
 basic_stream<Protocol, Executor, RatePolicy>::
 async_connect(
     endpoint_type const& ep,
@@ -822,8 +821,7 @@ template<
     class EndpointSequence,
     class RangeConnectHandler,
     class>
-BOOST_ASIO_INITFN_RESULT_TYPE(RangeConnectHandler,
-    void(error_code, typename Protocol::endpoint))
+BOOST_ASIO_INITFN_RESULT_TYPE(RangeConnectHandler,void(error_code, typename Protocol::endpoint))
 basic_stream<Protocol, Executor, RatePolicy>::
 async_connect(
     EndpointSequence const& endpoints,
@@ -845,8 +843,7 @@ template<
     class ConnectCondition,
     class RangeConnectHandler,
     class>
-BOOST_ASIO_INITFN_RESULT_TYPE(RangeConnectHandler,
-    void (error_code, typename Protocol::endpoint))
+BOOST_ASIO_INITFN_RESULT_TYPE(RangeConnectHandler,void (error_code, typename Protocol::endpoint))
 basic_stream<Protocol, Executor, RatePolicy>::
 async_connect(
     EndpointSequence const& endpoints,
@@ -867,8 +864,7 @@ template<class Protocol, class Executor, class RatePolicy>
 template<
     class Iterator,
     class IteratorConnectHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(IteratorConnectHandler,
-    void (error_code, Iterator))
+BOOST_ASIO_INITFN_RESULT_TYPE(IteratorConnectHandler,void (error_code, Iterator))
 basic_stream<Protocol, Executor, RatePolicy>::
 async_connect(
     Iterator begin, Iterator end,
@@ -889,8 +885,7 @@ template<
     class Iterator,
     class ConnectCondition,
     class IteratorConnectHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(IteratorConnectHandler,
-    void (error_code, Iterator))
+BOOST_ASIO_INITFN_RESULT_TYPE(IteratorConnectHandler,void (error_code, Iterator))
 basic_stream<Protocol, Executor, RatePolicy>::
 async_connect(
     Iterator begin, Iterator end,
@@ -911,8 +906,7 @@ async_connect(
 
 template<class Protocol, class Executor, class RatePolicy>
 template<class MutableBufferSequence, class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
-    void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 basic_stream<Protocol, Executor, RatePolicy>::
 async_read_some(
     MutableBufferSequence const& buffers,
@@ -932,8 +926,7 @@ async_read_some(
 
 template<class Protocol, class Executor, class RatePolicy>
 template<class ConstBufferSequence, class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
-    void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 basic_stream<Protocol, Executor, RatePolicy>::
 async_write_some(
     ConstBufferSequence const& buffers,
diff --git a/include/boost/beast/core/impl/buffered_read_stream.hpp b/include/boost/beast/core/impl/buffered_read_stream.hpp
index 39380688..7a85cb04 100644
--- a/include/boost/beast/core/impl/buffered_read_stream.hpp
+++ b/include/boost/beast/core/impl/buffered_read_stream.hpp
@@ -142,8 +142,7 @@ buffered_read_stream(Args&&... args)
 
 template<class Stream, class DynamicBuffer>
 template<class ConstBufferSequence, class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 buffered_read_stream<Stream, DynamicBuffer>::
 async_write_some(
     ConstBufferSequence const& buffers,
@@ -214,8 +213,7 @@ read_some(MutableBufferSequence const& buffers,
 
 template<class Stream, class DynamicBuffer>
 template<class MutableBufferSequence, class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 buffered_read_stream<Stream, DynamicBuffer>::
 async_read_some(
     MutableBufferSequence const& buffers,
diff --git a/include/boost/beast/core/impl/file_posix.ipp b/include/boost/beast/core/impl/file_posix.ipp
index 6d22503d..9b837d36 100644
--- a/include/boost/beast/core/impl/file_posix.ipp
+++ b/include/boost/beast/core/impl/file_posix.ipp
@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2015-2016 Vinnie Falco (vinnie dot falco at gmail dot com)
+// Copyright (c) 2015-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
 //
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
diff --git a/include/boost/beast/core/impl/file_stdio.ipp b/include/boost/beast/core/impl/file_stdio.ipp
index 46897f9c..6fa078b6 100644
--- a/include/boost/beast/core/impl/file_stdio.ipp
+++ b/include/boost/beast/core/impl/file_stdio.ipp
@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2015-2016 Vinnie Falco (vinnie dot falco at gmail dot com)
+// Copyright (c) 2015-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
 //
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
diff --git a/include/boost/beast/core/impl/file_win32.ipp b/include/boost/beast/core/impl/file_win32.ipp
index cd0939c1..8944a6bb 100644
--- a/include/boost/beast/core/impl/file_win32.ipp
+++ b/include/boost/beast/core/impl/file_win32.ipp
@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2015-2016 Vinnie Falco (vinnie dot falco at gmail dot com)
+// Copyright (c) 2015-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
 //
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
diff --git a/include/boost/beast/core/impl/flat_stream.hpp b/include/boost/beast/core/impl/flat_stream.hpp
index 10249053..575aa7ce 100644
--- a/include/boost/beast/core/impl/flat_stream.hpp
+++ b/include/boost/beast/core/impl/flat_stream.hpp
@@ -147,8 +147,7 @@ template<class NextLayer>
 template<
     class MutableBufferSequence,
     class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 flat_stream<NextLayer>::
 async_read_some(
     MutableBufferSequence const& buffers,
@@ -229,8 +228,7 @@ template<class NextLayer>
 template<
     class ConstBufferSequence,
     class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 flat_stream<NextLayer>::
 async_write_some(
     ConstBufferSequence const& buffers,
diff --git a/include/boost/beast/http/impl/file_body_win32.hpp b/include/boost/beast/http/impl/file_body_win32.hpp
index 1bf65d08..385a4879 100644
--- a/include/boost/beast/http/impl/file_body_win32.hpp
+++ b/include/boost/beast/http/impl/file_body_win32.hpp
@@ -544,8 +544,7 @@ template<
     class Protocol, class Executor,
     bool isRequest, class Fields,
     class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 async_write_some(
     net::basic_stream_socket<
         Protocol, Executor>& sock,
diff --git a/include/boost/beast/http/impl/read.hpp b/include/boost/beast/http/impl/read.hpp
index 1e49b292..51d2ea43 100644
--- a/include/boost/beast/http/impl/read.hpp
+++ b/include/boost/beast/http/impl/read.hpp
@@ -301,8 +301,7 @@ template<
     class DynamicBuffer,
     bool isRequest,
     class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 async_read_some(
     AsyncReadStream& stream,
     DynamicBuffer& buffer,
@@ -371,8 +370,7 @@ template<
     class DynamicBuffer,
     bool isRequest,
     class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 async_read_header(
     AsyncReadStream& stream,
     DynamicBuffer& buffer,
@@ -442,8 +440,7 @@ template<
     class DynamicBuffer,
     bool isRequest,
     class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 async_read(
     AsyncReadStream& stream,
     DynamicBuffer& buffer,
@@ -531,8 +528,7 @@ template<
     class DynamicBuffer,
     bool isRequest, class Body, class Allocator,
     class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 async_read(
     AsyncReadStream& stream,
     DynamicBuffer& buffer,
diff --git a/include/boost/beast/http/impl/write.hpp b/include/boost/beast/http/impl/write.hpp
index b770af89..910dcac4 100644
--- a/include/boost/beast/http/impl/write.hpp
+++ b/include/boost/beast/http/impl/write.hpp
@@ -463,8 +463,7 @@ template<
     class AsyncWriteStream,
     bool isRequest, class Body, class Fields,
     class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 async_write_some_impl(
     AsyncWriteStream& stream,
     serializer<isRequest, Body, Fields>& sr,
@@ -527,8 +526,7 @@ template<
     class AsyncWriteStream,
     bool isRequest, class Body, class Fields,
     class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 async_write_some(
     AsyncWriteStream& stream,
     serializer<isRequest, Body, Fields>& sr,
@@ -610,8 +608,7 @@ template<
     class AsyncWriteStream,
     bool isRequest, class Body, class Fields,
     class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 async_write_header(
     AsyncWriteStream& stream,
     serializer<isRequest, Body, Fields>& sr,
@@ -684,8 +681,7 @@ template<
     class AsyncWriteStream,
     bool isRequest, class Body, class Fields,
     class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 async_write(
     AsyncWriteStream& stream,
     serializer<isRequest, Body, Fields>& sr,
@@ -807,8 +803,7 @@ template<
     class WriteHandler>
 typename std::enable_if<
     is_mutable_body_writer<Body>::value,
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code, std::size_t))>::type
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)>::type
 async_write(
     AsyncWriteStream& stream,
     message<isRequest, Body, Fields>& msg,
@@ -837,8 +832,7 @@ template<
     class WriteHandler>
 typename std::enable_if<
     ! is_mutable_body_writer<Body>::value,
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code, std::size_t))>::type
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)>::type
 async_write(
     AsyncWriteStream& stream,
     message<isRequest, Body, Fields> const& msg,
diff --git a/include/boost/beast/http/read.hpp b/include/boost/beast/http/read.hpp
index d8eef0bf..aa8d1285 100644
--- a/include/boost/beast/http/read.hpp
+++ b/include/boost/beast/http/read.hpp
@@ -207,8 +207,7 @@ template<
     class DynamicBuffer,
     bool isRequest,
     class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 async_read_some(
     AsyncReadStream& stream,
     DynamicBuffer& buffer,
@@ -403,8 +402,7 @@ template<
     class DynamicBuffer,
     bool isRequest,
     class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 async_read_header(
     AsyncReadStream& stream,
     DynamicBuffer& buffer,
@@ -599,8 +597,7 @@ template<
     class DynamicBuffer,
     bool isRequest,
     class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 async_read(
     AsyncReadStream& stream,
     DynamicBuffer& buffer,
@@ -804,8 +801,7 @@ template<
     class DynamicBuffer,
     bool isRequest, class Body, class Allocator,
     class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 async_read(
     AsyncReadStream& stream,
     DynamicBuffer& buffer,
diff --git a/include/boost/beast/http/write.hpp b/include/boost/beast/http/write.hpp
index a5bebad7..05962161 100644
--- a/include/boost/beast/http/write.hpp
+++ b/include/boost/beast/http/write.hpp
@@ -172,8 +172,7 @@ template<
     class AsyncWriteStream,
     bool isRequest, class Body, class Fields,
     class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 async_write_some(
     AsyncWriteStream& stream,
     serializer<isRequest, Body, Fields>& sr,
@@ -301,8 +300,7 @@ template<
     class AsyncWriteStream,
     bool isRequest, class Body, class Fields,
     class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 async_write_header(
     AsyncWriteStream& stream,
     serializer<isRequest, Body, Fields>& sr,
@@ -421,8 +419,7 @@ template<
     class AsyncWriteStream,
     bool isRequest, class Body, class Fields,
     class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 async_write(
     AsyncWriteStream& stream,
     serializer<isRequest, Body, Fields>& sr,
@@ -646,13 +643,11 @@ template<
     bool isRequest, class Body, class Fields,
     class WriteHandler>
 #if BOOST_BEAST_DOXYGEN
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 #else
 typename std::enable_if<
     is_mutable_body_writer<Body>::value,
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code, std::size_t))>::type
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)>::type
 #endif
 async_write(
     AsyncWriteStream& stream,
@@ -709,13 +704,11 @@ template<
     bool isRequest, class Body, class Fields,
     class WriteHandler>
 #if BOOST_BEAST_DOXYGEN
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 #else
 typename std::enable_if<
     ! is_mutable_body_writer<Body>::value,
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code, std::size_t))>::type
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)>::type
 #endif
 async_write(
     AsyncWriteStream& stream,
diff --git a/include/boost/beast/version.hpp b/include/boost/beast/version.hpp
index d69a19c9..f6b1132b 100644
--- a/include/boost/beast/version.hpp
+++ b/include/boost/beast/version.hpp
@@ -13,7 +13,7 @@
 #include <boost/beast/core/detail/config.hpp>
 #include <boost/config.hpp>
 
-/** @def BOOST_BEAST_API_VERSION 
+/*  BOOST_BEAST_VERSION
 
     Identifies the API version of Beast.
 
diff --git a/include/boost/beast/websocket/impl/accept.hpp b/include/boost/beast/websocket/impl/accept.hpp
index ddf32a40..fb1c33f4 100644
--- a/include/boost/beast/websocket/impl/accept.hpp
+++ b/include/boost/beast/websocket/impl/accept.hpp
@@ -545,8 +545,7 @@ accept(
 template<class NextLayer, bool deflateSupported>
 template<
     class AcceptHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    AcceptHandler, void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)
 stream<NextLayer, deflateSupported>::
 async_accept(
     AcceptHandler&& handler)
@@ -568,8 +567,7 @@ template<class NextLayer, bool deflateSupported>
 template<
     class ResponseDecorator,
     class AcceptHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    AcceptHandler, void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)
 stream<NextLayer, deflateSupported>::
 async_accept_ex(
     ResponseDecorator const& decorator,
@@ -597,8 +595,7 @@ template<
     class AcceptHandler>
 typename std::enable_if<
     ! http::detail::is_header<ConstBufferSequence>::value,
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        AcceptHandler, void(error_code))>::type
+    BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)>::type
 stream<NextLayer, deflateSupported>::
 async_accept(
     ConstBufferSequence const& buffers,
@@ -627,8 +624,7 @@ template<
     class AcceptHandler>
 typename std::enable_if<
     ! http::detail::is_header<ConstBufferSequence>::value,
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        AcceptHandler, void(error_code))>::type
+    BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)>::type
 stream<NextLayer, deflateSupported>::
 async_accept_ex(
     ConstBufferSequence const& buffers,
@@ -658,8 +654,7 @@ template<class NextLayer, bool deflateSupported>
 template<
     class Body, class Allocator,
     class AcceptHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    AcceptHandler, void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)
 stream<NextLayer, deflateSupported>::
 async_accept(
     http::request<Body, http::basic_fields<Allocator>> const& req,
@@ -683,8 +678,7 @@ template<
     class Body, class Allocator,
     class ResponseDecorator,
     class AcceptHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    AcceptHandler, void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)
 stream<NextLayer, deflateSupported>::
 async_accept_ex(
     http::request<Body, http::basic_fields<Allocator>> const& req,
diff --git a/include/boost/beast/websocket/impl/close.hpp b/include/boost/beast/websocket/impl/close.hpp
index 42cf2f97..0df879f3 100644
--- a/include/boost/beast/websocket/impl/close.hpp
+++ b/include/boost/beast/websocket/impl/close.hpp
@@ -381,8 +381,7 @@ close(close_reason const& cr, error_code& ec)
 
 template<class NextLayer, bool deflateSupported>
 template<class CloseHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    CloseHandler, void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(CloseHandler)
 stream<NextLayer, deflateSupported>::
 async_close(close_reason const& cr, CloseHandler&& handler)
 {
diff --git a/include/boost/beast/websocket/impl/handshake.hpp b/include/boost/beast/websocket/impl/handshake.hpp
index 0cc33a9b..0ccb1102 100644
--- a/include/boost/beast/websocket/impl/handshake.hpp
+++ b/include/boost/beast/websocket/impl/handshake.hpp
@@ -267,8 +267,7 @@ do_handshake(
 
 template<class NextLayer, bool deflateSupported>
 template<class HandshakeHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    HandshakeHandler, void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(HandshakeHandler)
 stream<NextLayer, deflateSupported>::
 async_handshake(
     string_view host,
@@ -293,8 +292,7 @@ async_handshake(
 
 template<class NextLayer, bool deflateSupported>
 template<class HandshakeHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    HandshakeHandler, void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(HandshakeHandler)
 stream<NextLayer, deflateSupported>::
 async_handshake(
     response_type& res,
@@ -470,8 +468,7 @@ handshake_ex(response_type& res,
 
 template<class NextLayer, bool deflateSupported>
 template<class RequestDecorator, class HandshakeHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    HandshakeHandler, void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(HandshakeHandler)
 stream<NextLayer, deflateSupported>::
 async_handshake_ex(string_view host,
     string_view target,
@@ -503,8 +500,7 @@ async_handshake_ex(string_view host,
 
 template<class NextLayer, bool deflateSupported>
 template<class RequestDecorator, class HandshakeHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    HandshakeHandler, void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(HandshakeHandler)
 stream<NextLayer, deflateSupported>::
 async_handshake_ex(response_type& res,
     string_view host,
diff --git a/include/boost/beast/websocket/impl/ping.hpp b/include/boost/beast/websocket/impl/ping.hpp
index 822af88c..35a314c7 100644
--- a/include/boost/beast/websocket/impl/ping.hpp
+++ b/include/boost/beast/websocket/impl/ping.hpp
@@ -286,8 +286,7 @@ pong(ping_data const& payload, error_code& ec)
 
 template<class NextLayer, bool deflateSupported>
 template<class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(WriteHandler)
 stream<NextLayer, deflateSupported>::
 async_ping(ping_data const& payload, WriteHandler&& handler)
 {
@@ -305,8 +304,7 @@ async_ping(ping_data const& payload, WriteHandler&& handler)
 
 template<class NextLayer, bool deflateSupported>
 template<class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code))
+BOOST_BEAST_ASYNC_RESULT1(WriteHandler)
 stream<NextLayer, deflateSupported>::
 async_pong(ping_data const& payload, WriteHandler&& handler)
 {
diff --git a/include/boost/beast/websocket/impl/read.hpp b/include/boost/beast/websocket/impl/read.hpp
index 101983c8..dac24146 100644
--- a/include/boost/beast/websocket/impl/read.hpp
+++ b/include/boost/beast/websocket/impl/read.hpp
@@ -795,8 +795,7 @@ read(DynamicBuffer& buffer, error_code& ec)
 
 template<class NextLayer, bool deflateSupported>
 template<class DynamicBuffer, class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 stream<NextLayer, deflateSupported>::
 async_read(DynamicBuffer& buffer, ReadHandler&& handler)
 {
@@ -870,8 +869,7 @@ read_some(
 
 template<class NextLayer, bool deflateSupported>
 template<class DynamicBuffer, class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 stream<NextLayer, deflateSupported>::
 async_read_some(
     DynamicBuffer& buffer,
@@ -1254,8 +1252,7 @@ loop:
 
 template<class NextLayer, bool deflateSupported>
 template<class MutableBufferSequence, class ReadHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    ReadHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
 stream<NextLayer, deflateSupported>::
 async_read_some(
     MutableBufferSequence const& buffers,
diff --git a/include/boost/beast/websocket/impl/write.hpp b/include/boost/beast/websocket/impl/write.hpp
index 11aa4218..2da69efb 100644
--- a/include/boost/beast/websocket/impl/write.hpp
+++ b/include/boost/beast/websocket/impl/write.hpp
@@ -698,8 +698,7 @@ write_some(bool fin,
 
 template<class NextLayer, bool deflateSupported>
 template<class ConstBufferSequence, class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 stream<NextLayer, deflateSupported>::
 async_write_some(bool fin,
     ConstBufferSequence const& bs, WriteHandler&& handler)
@@ -755,8 +754,7 @@ write(ConstBufferSequence const& buffers, error_code& ec)
 
 template<class NextLayer, bool deflateSupported>
 template<class ConstBufferSequence, class WriteHandler>
-BOOST_ASIO_INITFN_RESULT_TYPE(
-    WriteHandler, void(error_code, std::size_t))
+BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
 stream<NextLayer, deflateSupported>::
 async_write(
     ConstBufferSequence const& bs, WriteHandler&& handler)
diff --git a/include/boost/beast/websocket/stream.hpp b/include/boost/beast/websocket/stream.hpp
index f386376b..b13fdbe0 100644
--- a/include/boost/beast/websocket/stream.hpp
+++ b/include/boost/beast/websocket/stream.hpp
@@ -877,8 +877,7 @@ public:
         @li <a href="https://tools.ietf.org/html/rfc7230#section-5.3.1">origin-form (RFC7230)</a>
     */
     template<class HandshakeHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        HandshakeHandler, void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(HandshakeHandler)
     async_handshake(
         string_view host,
         string_view target,
@@ -961,8 +960,7 @@ public:
         @li <a href="https://tools.ietf.org/html/rfc7230#section-5.3.1">origin-form (RFC7230)</a>
     */
     template<class HandshakeHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        HandshakeHandler, void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(HandshakeHandler)
     async_handshake(
         response_type& res,
         string_view host,
@@ -1283,8 +1281,7 @@ public:
         @li <a href="https://tools.ietf.org/html/rfc6455#section-4.2">Websocket Opening Handshake Server Requirements (RFC6455)</a>
     */
     template<class AcceptHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        AcceptHandler, void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)
     async_accept(AcceptHandler&& handler);
 
     /** Perform the WebSocket handshake asynchronously in the server role.
@@ -1354,8 +1351,7 @@ public:
 #else
     typename std::enable_if<
         ! http::detail::is_header<ConstBufferSequence>::value,
-        BOOST_ASIO_INITFN_RESULT_TYPE(
-            AcceptHandler, void(error_code))>::type
+        BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)>::type
 #endif
     async_accept(
         ConstBufferSequence const& buffers,
@@ -1413,8 +1409,7 @@ public:
     template<
         class Body, class Allocator,
         class AcceptHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        AcceptHandler, void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)
     async_accept(
         http::request<Body,
             http::basic_fields<Allocator>> const& req,
@@ -1546,8 +1541,7 @@ public:
         @li <a href="https://tools.ietf.org/html/rfc6455#section-7.1.2">Websocket Closing Handshake (RFC6455)</a>
     */
     template<class CloseHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        CloseHandler, void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(CloseHandler)
     async_close(close_reason const& cr, CloseHandler&& handler);
 
     //--------------------------------------------------------------------------
@@ -1644,8 +1638,7 @@ public:
         manner equivalent to using `net::post`.
     */
     template<class WriteHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(WriteHandler)
     async_ping(ping_data const& payload, WriteHandler&& handler);
 
     /** Send a websocket pong control frame.
@@ -1748,8 +1741,7 @@ public:
         manner equivalent to using `net::post`.
     */
     template<class WriteHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(WriteHandler)
     async_pong(ping_data const& payload, WriteHandler&& handler);
 
     //--------------------------------------------------------------------------
@@ -1905,8 +1897,7 @@ public:
         manner equivalent to using `net::post`.
     */
     template<class DynamicBuffer, class ReadHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        ReadHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
     async_read(
         DynamicBuffer& buffer,
         ReadHandler&& handler);
@@ -2081,8 +2072,7 @@ public:
         manner equivalent to using `net::post`.
     */
     template<class DynamicBuffer, class ReadHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        ReadHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
     async_read_some(
         DynamicBuffer& buffer,
         std::size_t limit,
@@ -2253,8 +2243,7 @@ public:
         manner equivalent to using `net::post`.
     */
     template<class MutableBufferSequence, class ReadHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        ReadHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
     async_read_some(
         MutableBufferSequence const& buffers,
         ReadHandler&& handler);
@@ -2375,8 +2364,7 @@ public:
     template<
         class ConstBufferSequence,
         class WriteHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
     async_write(
         ConstBufferSequence const& buffers,
         WriteHandler&& handler);
@@ -2495,8 +2483,7 @@ public:
         manner equivalent to using `net::post`.
     */
     template<class ConstBufferSequence, class WriteHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        WriteHandler, void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
     async_write_some(bool fin,
         ConstBufferSequence const& buffers, WriteHandler&& handler);
 
@@ -2538,8 +2525,7 @@ public:
         error_code& ec);
 
     template<class RequestDecorator, class HandshakeHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        HandshakeHandler, void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(HandshakeHandler)
     async_handshake_ex(
         string_view host,
         string_view target,
@@ -2547,8 +2533,7 @@ public:
         HandshakeHandler&& handler);
 
     template<class RequestDecorator, class HandshakeHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        HandshakeHandler, void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(HandshakeHandler)
     async_handshake_ex(
         response_type& res,
         string_view host,
@@ -2600,8 +2585,7 @@ public:
     template<
         class ResponseDecorator,
         class AcceptHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        AcceptHandler, void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)
     async_accept_ex(
         ResponseDecorator const& decorator,
         AcceptHandler&& handler);
@@ -2612,8 +2596,7 @@ public:
         class AcceptHandler>
     typename std::enable_if<
         ! http::detail::is_header<ConstBufferSequence>::value,
-        BOOST_ASIO_INITFN_RESULT_TYPE(
-            AcceptHandler, void(error_code))>::type
+        BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)>::type
     async_accept_ex(
         ConstBufferSequence const& buffers,
         ResponseDecorator const& decorator,
@@ -2623,8 +2606,7 @@ public:
         class Body, class Allocator,
         class ResponseDecorator,
         class AcceptHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(
-        AcceptHandler, void(error_code))
+    BOOST_BEAST_ASYNC_RESULT1(AcceptHandler)
     async_accept_ex(
         http::request<Body,
             http::basic_fields<Allocator>> const& req,
diff --git a/test/beast/core/async_base.cpp b/test/beast/core/async_base.cpp
index bfd7ba61..a8f5e976 100644
--- a/test/beast/core/async_base.cpp
+++ b/test/beast/core/async_base.cpp
@@ -581,7 +581,7 @@ public:
 
     // Asynchronously read into a buffer until the buffer is full, or an error occurs
     template<class AsyncReadStream, class ReadHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler, void (error_code, std::size_t))
+    typename net::async_result<ReadHandler, void(error_code, std::size_t)>::return_type
     async_read(AsyncReadStream& stream, net::mutable_buffer buffer, ReadHandler&& handler)
     {
         using handler_type = BOOST_ASIO_HANDLER_TYPE(ReadHandler, void(error_code, std::size_t));
diff --git a/test/doc/core_4_layers.cpp b/test/doc/core_4_layers.cpp
index dc7018d0..06cbfeea 100644
--- a/test/doc/core_4_layers.cpp
+++ b/test/doc/core_4_layers.cpp
@@ -244,8 +244,7 @@ public:
 
     /// Read some data from the stream asynchronously
     template <class MutableBufferSequence, class ReadHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler,
-        void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(ReadHandler)
     async_read_some(
         MutableBufferSequence const& buffers,
         ReadHandler&& handler)
@@ -261,8 +260,7 @@ public:
 
     /// Write some data to the stream asynchronously
     template <class ConstBufferSequence, class WriteHandler>
-    BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler,
-        void(error_code, std::size_t))
+    BOOST_BEAST_ASYNC_RESULT2(WriteHandler)
     async_write_some(
         ConstBufferSequence const& buffers,
         WriteHandler&& handler)