diff --git a/README.md b/README.md
index 9fb4feaaa1..177e850eb9 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # readable-stream
 
-***Node-core v6.3.1 streams for userland*** [![Build Status](https://travis-ci.org/nodejs/readable-stream.svg?branch=master)](https://travis-ci.org/nodejs/readable-stream)
+***Node-core v6.4.0 streams for userland*** [![Build Status](https://travis-ci.org/nodejs/readable-stream.svg?branch=master)](https://travis-ci.org/nodejs/readable-stream)
 
 
 [![NPM](https://nodei.co/npm/readable-stream.png?downloads=true&downloadRank=true)](https://nodei.co/npm/readable-stream/)
diff --git a/build/build.js b/build/build.js
index 5d25fbb6bc..2bdbedc57e 100644
--- a/build/build.js
+++ b/build/build.js
@@ -50,6 +50,7 @@ function processFile (inputLoc, out, replacements) {
     if (inputLoc.slice(-3) === '.js') {
       const transformed = babel.transform(data, {
         plugins: [
+          'transform-es2015-parameters',
           'transform-es2015-arrow-functions',
           'transform-es2015-block-scoping',
           'transform-es2015-template-literals',
@@ -103,7 +104,7 @@ hyperquest(testlisturl).pipe(bl(function (err, data) {
 
   $('table.files .js-navigation-open').each(function () {
     var file = $(this).text()
-    if (/^test-stream/.test(file) && !/-wrap(?:-encoding)?\.js$/.test(file) && file !== 'test-stream2-httpclient-response-end.js' && file !== 'test-stream-base-no-abort.js')
+    if (/^test-stream/.test(file) && !/-wrap(?:-encoding)?\.js$/.test(file) && file !== 'test-stream2-httpclient-response-end.js' && file !== 'test-stream-base-no-abort.js' && file !== 'test-stream-preprocess.js')
       processTestFile(file)
   })
 }))
diff --git a/build/package.json b/build/package.json
index bba632559e..9f6ade5fa1 100644
--- a/build/package.json
+++ b/build/package.json
@@ -8,6 +8,7 @@
     "babel-plugin-transform-es2015-arrow-functions": "^6.5.2",
     "babel-plugin-transform-es2015-block-scoping": "^6.5.0",
     "babel-plugin-transform-es2015-for-of": "^6.8.0",
+    "babel-plugin-transform-es2015-parameters": "^6.11.4",
     "babel-plugin-transform-es2015-shorthand-properties": "^6.8.0",
     "babel-plugin-transform-es2015-template-literals": "^6.8.0",
     "bl": "~0.6.0",
diff --git a/build/test-replacements.js b/build/test-replacements.js
index 33246f3a92..d6ec87c430 100644
--- a/build/test-replacements.js
+++ b/build/test-replacements.js
@@ -60,6 +60,10 @@ module.exports['test-stream2-transform.js'] = [
 module.exports['test-stream2-writable.js'] = [
     altForEachImplReplacement
   , altForEachUseReplacement
+  , [
+    /'latin1',/g,
+    '\'binary\','
+  ]
 ]
 
 module.exports['test-stream-big-packet.js'] = [
@@ -274,3 +278,9 @@ module.exports['test-stream2-readable-from-list.js'] = [
     'require(\'../../lib/internal/streams/BufferList\')'
   ]
 ]
+module.exports['test-stream-writev.js'] = [
+  [
+    /'latin1'/g,
+    `'binary'`
+  ]
+]
diff --git a/doc/stream.md b/doc/stream.md
index fc269c8e38..4a88ac8fe4 100644
--- a/doc/stream.md
+++ b/doc/stream.md
@@ -1,6 +1,6 @@
 # Stream
 
-    Stability: 2 - Stable
+> Stability: 2 - Stable
 
 A stream is an abstract interface for working with streaming data in Node.js.
 The `stream` module provides a base API that makes it easy to build objects
@@ -20,7 +20,7 @@ const stream = require('stream');
 ```
 
 While it is important for all Node.js users to understand how streams works,
-the `stream` module itself is most useful for developer's that are creating new
+the `stream` module itself is most useful for developers that are creating new
 types of stream instances. Developer's who are primarily *consuming* stream
 objects will rarely (if ever) have need to use the `stream` module directly.
 
@@ -343,7 +343,7 @@ The buffered data will be flushed when either the [`stream.uncork()`][] or
 [`stream.end()`][stream-end] methods are called.
 
 The primary intent of `writable.cork()` is to avoid a situation where writing
-many small chunks of data to a stream do not cause an backup in the internal
+many small chunks of data to a stream do not cause a backup in the internal
 buffer that would have an adverse impact on performance. In such situations,
 implementations that implement the `writable._writev()` method can perform
 buffered writes in a more optimized manner.
@@ -411,7 +411,7 @@ If the `writable.cork()` method is called multiple times on a stream, the same
 number of calls to `writable.uncork()` must be called to flush the buffered
 data.
 
-```
+```js
 stream.cork();
 stream.write('some ');
 stream.cork();
@@ -444,7 +444,7 @@ first argument. To reliably detect write errors, add a listener for the
 The return value indicates whether the written `chunk` was buffered internally
 and the buffer has exceeded the `highWaterMark` configured when the stream was
 created. If `false` is returned, further attempts to write data to the stream
-should be paused until the `'drain'` event is emitted.
+should be paused until the [`'drain'`][] event is emitted.
 
 A Writable stream in object mode will always ignore the `encoding` argument.
 
@@ -676,7 +676,7 @@ rr.on('end', () => {
 
 The output of running this script is:
 
-```
+```txt
 $ node test.js
 readable: null
 end
@@ -1262,7 +1262,7 @@ write succeeded.
 It is important to note that all calls to `writable.write()` that occur between
 the time `writable._write()` is called and the `callback` is called will cause
 the written data to be buffered. Once the `callback` is invoked, the stream will
-emit a `'drain'` event. If a stream implementation is capable of processing
+emit a [`'drain'`][] event. If a stream implementation is capable of processing
 multiple chunks of data at once, the `writable._writev()` method should be
 implemented.
 
@@ -1554,7 +1554,7 @@ class Counter extends Readable {
 A [Duplex][] stream is one that implements both [Readable][] and [Writable][],
 such as a TCP socket connection.
 
-Because Javascript does not have support for multiple inheritance, the
+Because JavaScript does not have support for multiple inheritance, the
 `stream.Duplex` class is extended to implement a [Duplex][] stream (as opposed
 to extending the `stream.Readable` *and* `stream.Writable` classes).
 
@@ -1968,36 +1968,32 @@ readable buffer so there is nothing for a user to consume.
 [`'end'`]: #stream_event_end
 [`'finish'`]: #stream_event_finish
 [`'readable'`]: #stream_event_readable
-[`buf.toString(encoding)`]: https://nodejs.org/docs/v6.3.1/api/buffer.html#buffer_buf_tostring_encoding_start_end
-[`EventEmitter`]: https://nodejs.org/docs/v6.3.1/api/events.html#events_class_eventemitter
-[`process.stderr`]: https://nodejs.org/docs/v6.3.1/api/process.html#process_process_stderr
-[`process.stdin`]: https://nodejs.org/docs/v6.3.1/api/process.html#process_process_stdin
-[`process.stdout`]: https://nodejs.org/docs/v6.3.1/api/process.html#process_process_stdout
+[`EventEmitter`]: https://nodejs.org/docs/v6.4.0/api/events.html#events_class_eventemitter
+[`process.stderr`]: https://nodejs.org/docs/v6.4.0/api/process.html#process_process_stderr
+[`process.stdin`]: https://nodejs.org/docs/v6.4.0/api/process.html#process_process_stdin
+[`process.stdout`]: https://nodejs.org/docs/v6.4.0/api/process.html#process_process_stdout
 [`stream.cork()`]: #stream_writable_cork
 [`stream.pipe()`]: #stream_readable_pipe_destination_options
 [`stream.uncork()`]: #stream_writable_uncork
 [`stream.unpipe()`]: #stream_readable_unpipe_destination
 [`stream.wrap()`]: #stream_readable_wrap_stream
-[`tls.CryptoStream`]: https://nodejs.org/docs/v6.3.1/api/tls.html#tls_class_cryptostream
 [API for Stream Consumers]: #stream_api_for_stream_consumers
 [API for Stream Implementers]: #stream_api_for_stream_implementers
-[child process stdin]: https://nodejs.org/docs/v6.3.1/api/child_process.html#child_process_child_stdin
-[child process stdout and stderr]: https://nodejs.org/docs/v6.3.1/api/child_process.html#child_process_child_stdout
+[child process stdin]: https://nodejs.org/docs/v6.4.0/api/child_process.html#child_process_child_stdin
+[child process stdout and stderr]: https://nodejs.org/docs/v6.4.0/api/child_process.html#child_process_child_stdout
 [Compatibility]: #stream_compatibility_with_older_node_js_versions
 [crypto]: crypto.html
 [Duplex]: #stream_class_stream_duplex
-[fs read streams]: https://nodejs.org/docs/v6.3.1/api/fs.html#fs_class_fs_readstream
-[fs write streams]: https://nodejs.org/docs/v6.3.1/api/fs.html#fs_class_fs_writestream
-[`fs.createReadStream()`]: https://nodejs.org/docs/v6.3.1/api/fs.html#fs_fs_createreadstream_path_options
-[`fs.createWriteStream()`]: https://nodejs.org/docs/v6.3.1/api/fs.html#fs_fs_createwritestream_path_options
-[`net.Socket`]: https://nodejs.org/docs/v6.3.1/api/net.html#net_class_net_socket
-[`zlib.createDeflate()`]: https://nodejs.org/docs/v6.3.1/api/zlib.html#zlib_zlib_createdeflate_options
-[HTTP requests, on the client]: https://nodejs.org/docs/v6.3.1/api/http.html#http_class_http_clientrequest
-[HTTP responses, on the server]: https://nodejs.org/docs/v6.3.1/api/http.html#http_class_http_serverresponse
-[http-incoming-message]: https://nodejs.org/docs/v6.3.1/api/http.html#http_class_http_incomingmessage
-[Object mode]: #stream_object_mode
+[fs read streams]: https://nodejs.org/docs/v6.4.0/api/fs.html#fs_class_fs_readstream
+[fs write streams]: https://nodejs.org/docs/v6.4.0/api/fs.html#fs_class_fs_writestream
+[`fs.createReadStream()`]: https://nodejs.org/docs/v6.4.0/api/fs.html#fs_fs_createreadstream_path_options
+[`fs.createWriteStream()`]: https://nodejs.org/docs/v6.4.0/api/fs.html#fs_fs_createwritestream_path_options
+[`net.Socket`]: https://nodejs.org/docs/v6.4.0/api/net.html#net_class_net_socket
+[`zlib.createDeflate()`]: https://nodejs.org/docs/v6.4.0/api/zlib.html#zlib_zlib_createdeflate_options
+[HTTP requests, on the client]: https://nodejs.org/docs/v6.4.0/api/http.html#http_class_http_clientrequest
+[HTTP responses, on the server]: https://nodejs.org/docs/v6.4.0/api/http.html#http_class_http_serverresponse
+[http-incoming-message]: https://nodejs.org/docs/v6.4.0/api/http.html#http_class_http_incomingmessage
 [Readable]: #stream_class_stream_readable
-[SimpleProtocol v2]: #stream_example_simpleprotocol_parser_v2
 [stream-_flush]: #stream_transform_flush_callback
 [stream-_read]: #stream_readable_read_size_1
 [stream-_transform]: #stream_transform_transform_chunk_encoding_callback
@@ -2009,7 +2005,7 @@ readable buffer so there is nothing for a user to consume.
 [stream-read]: #stream_readable_read_size
 [stream-resume]: #stream_readable_resume
 [stream-write]: #stream_writable_write_chunk_encoding_callback
-[TCP sockets]: https://nodejs.org/docs/v6.3.1/api/net.html#net_class_net_socket
+[TCP sockets]: https://nodejs.org/docs/v6.4.0/api/net.html#net_class_net_socket
 [Transform]: #stream_class_stream_transform
 [Writable]: #stream_class_stream_writable
 [zlib]: zlib.html
diff --git a/package.json b/package.json
index 42930904e9..a5d2a0bdd7 100644
--- a/package.json
+++ b/package.json
@@ -15,6 +15,7 @@
   "devDependencies": {
     "assert": "~1.4.0",
     "babel-polyfill": "^6.9.1",
+    "buffer": "^4.9.0",
     "nyc": "^6.4.0",
     "tap": "~0.7.1",
     "tape": "~4.5.1",
diff --git a/test/common.js b/test/common.js
index 4e933019c8..3307409b0f 100644
--- a/test/common.js
+++ b/test/common.js
@@ -41,19 +41,21 @@ util.inherits = require('inherits');
 
 var Timer = { now: function () {} };
 
-var testRoot = path.resolve(process.env.NODE_TEST_DIR || path.dirname(__filename));
+var testRoot = process.env.NODE_TEST_DIR ? path.resolve(process.env.NODE_TEST_DIR) : __dirname;
 
-exports.testDir = path.dirname(__filename);
+exports.testDir = __dirname;
 exports.fixturesDir = path.join(exports.testDir, 'fixtures');
 exports.libDir = path.join(exports.testDir, '../lib');
 exports.tmpDirName = 'tmp';
 exports.PORT = +process.env.NODE_COMMON_PORT || 12346;
 exports.isWindows = process.platform === 'win32';
-exports.isWOW64 = exports.isWindows && process.env['PROCESSOR_ARCHITEW6432'] !== undefined;
+exports.isWOW64 = exports.isWindows && process.env.PROCESSOR_ARCHITEW6432 !== undefined;
 exports.isAix = process.platform === 'aix';
 exports.isLinuxPPCBE = process.platform === 'linux' && process.arch === 'ppc64' && os.endianness() === 'BE';
 exports.isSunOS = process.platform === 'sunos';
 exports.isFreeBSD = process.platform === 'freebsd';
+exports.isLinux = process.platform === 'linux';
+exports.isOSX = process.platform === 'darwin';
 
 exports.enoughTestMem = os.totalmem() > 0x40000000; /* 1 Gb */
 exports.rootDir = exports.isWindows ? 'c:\\' : '/';
@@ -81,7 +83,7 @@ function rmdirSync(p, originalEr) {
   } catch (e) {
     if (e.code === 'ENOTDIR') throw originalEr;
     if (e.code === 'ENOTEMPTY' || e.code === 'EEXIST' || e.code === 'EPERM') {
-      var enc = process.platform === 'linux' ? 'buffer' : 'utf8';
+      var enc = exports.isLinux ? 'buffer' : 'utf8';
       fs.readdirSync(p, forEach(enc), function (f) {
         if (f instanceof Buffer) {
           var buf = Buffer.concat([Buffer.from(p), Buffer.from(path.sep), f]);
@@ -111,7 +113,7 @@ var inFreeBSDJail = null;
 var localhostIPv4 = null;
 
 exports.localIPv6Hosts = ['localhost'];
-if (process.platform === 'linux') {
+if (exports.isLinux) {
   exports.localIPv6Hosts = [
   // Debian/Ubuntu
   'ip6-localhost', 'ip6-loopback',
@@ -128,7 +130,7 @@ if (process.platform === 'linux') {
     get: function () {
       if (inFreeBSDJail !== null) return inFreeBSDJail;
 
-      if (process.platform === 'freebsd' && child_process.execSync('sysctl -n security.jail.jailed').toString() === '1\n') {
+      if (exports.isFreeBSD && child_process.execSync('sysctl -n security.jail.jailed').toString() === '1\n') {
         inFreeBSDJail = true;
       } else {
         inFreeBSDJail = false;
@@ -348,6 +350,15 @@ if (global.Symbol) {
   knownGlobals.push(Symbol);
 }
 
+function allowGlobals() {
+  for (var _len = arguments.length, whitelist = Array(_len), _key = 0; _key < _len; _key++) {
+    whitelist[_key] = arguments[_key];
+  }
+
+  knownGlobals = knownGlobals.concat(whitelist);
+}
+exports.allowGlobals = allowGlobals;
+
 /*<replacement>*/
 if (typeof constructor == 'function') knownGlobals.push(constructor);
 if (typeof DTRACE_NET_SOCKET_READ == 'function') knownGlobals.push(DTRACE_NET_SOCKET_READ);
@@ -479,7 +490,7 @@ exports.nodeProcessAborted = function nodeProcessAborted(exitCode, signal) {
 
   // On Windows, v8's base::OS::Abort triggers an access violation,
   // which corresponds to exit code 3221225477 (0xC0000005)
-  if (process.platform === 'win32') expectedExitCodes = [3221225477];
+  if (exports.isWindows) expectedExitCodes = [3221225477];
 
   // When using --abort-on-uncaught-exception, V8 will use
   // base::OS::Abort to terminate the process.
diff --git a/test/parallel/test-stream-push-order.js b/test/parallel/test-stream-push-order.js
index 39f44ede55..9f4fa15758 100644
--- a/test/parallel/test-stream-push-order.js
+++ b/test/parallel/test-stream-push-order.js
@@ -30,4 +30,4 @@ s.read(0);
 process.on('exit', function () {
   assert.deepStrictEqual(s._readableState.buffer.join(','), '1,2,3,4,5,6');
   console.log('ok');
-});
+});
\ No newline at end of file
diff --git a/test/parallel/test-stream2-writable.js b/test/parallel/test-stream2-writable.js
index 83ecaf6ec2..d695254646 100644
--- a/test/parallel/test-stream2-writable.js
+++ b/test/parallel/test-stream2-writable.js
@@ -133,7 +133,7 @@ test('write bufferize', function (t) {
     highWaterMark: 100
   });
 
-  var encodings = ['hex', 'utf8', 'utf-8', 'ascii', 'binary', 'base64', 'ucs2', 'ucs-2', 'utf16le', 'utf-16le', undefined];
+  var encodings = ['hex', 'utf8', 'utf-8', 'ascii', 'binary', 'binary', 'base64', 'ucs2', 'ucs-2', 'utf16le', 'utf-16le', undefined];
 
   tw.on('finish', function () {
     t.same(tw.buffer, chunks, 'got the expected chunks');
@@ -159,7 +159,7 @@ test('write no bufferize', function (t) {
     return TestWriter.prototype._write.call(this, chunk, encoding, cb);
   };
 
-  var encodings = ['hex', 'utf8', 'utf-8', 'ascii', 'binary', 'base64', 'ucs2', 'ucs-2', 'utf16le', 'utf-16le', undefined];
+  var encodings = ['hex', 'utf8', 'utf-8', 'ascii', 'binary', 'binary', 'base64', 'ucs2', 'ucs-2', 'utf16le', 'utf-16le', undefined];
 
   tw.on('finish', function () {
     t.same(tw.buffer, chunks, 'got the expected chunks');
@@ -251,7 +251,7 @@ test('encoding should be ignored for buffers', function (t) {
     t.end();
   };
   var buf = bufferShim.from(hex, 'hex');
-  tw.write(buf, 'binary');
+  tw.write(buf, 'latin1');
 });
 
 test('writables are not pipable', function (t) {