diff --git a/test/simple/test-stream2-basic.js b/test/simple/test-stream2-basic.js
new file mode 100644
index 00000000000..c28cdc917a6
--- /dev/null
+++ b/test/simple/test-stream2-basic.js
@@ -0,0 +1,312 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+
+var common = require('../common.js');
+var R = require('_stream_readable');
+var assert = require('assert');
+
+var util = require('util');
+var EE = require('events').EventEmitter;
+
+function TestReader(n) {
+  R.apply(this);
+  this._buffer = new Buffer(n || 100);
+  this._buffer.fill('x');
+  this._pos = 0;
+  this._bufs = 10;
+}
+
+util.inherits(TestReader, R);
+
+TestReader.prototype.read = function(n) {
+  var max = this._buffer.length - this._pos;
+  n = n || max;
+  n = Math.max(n, 0);
+  var toRead = Math.min(n, max);
+  if (toRead === 0) {
+    // simulate the read buffer filling up with some more bytes some time
+    // in the future.
+    setTimeout(function() {
+      this._pos = 0;
+      this._bufs -= 1;
+      if (this._bufs <= 0) {
+        // read them all!
+        if (!this.ended) {
+          this.emit('end');
+          this.ended = true;
+        }
+      } else {
+        this.emit('readable');
+      }
+    }.bind(this), 10);
+    return null;
+  }
+
+  var ret = this._buffer.slice(this._pos, this._pos + toRead);
+  this._pos += toRead;
+  return ret;
+};
+
+/////
+
+function TestWriter() {
+  EE.apply(this);
+  this.received = [];
+  this.flush = false;
+}
+
+util.inherits(TestWriter, EE);
+
+TestWriter.prototype.write = function(c) {
+  this.received.push(c.toString());
+  this.emit('write', c);
+  return true;
+
+  // flip back and forth between immediate acceptance and not.
+  this.flush = !this.flush;
+  if (!this.flush) setTimeout(this.emit.bind(this, 'drain'), 10);
+  return this.flush;
+};
+
+TestWriter.prototype.end = function(c) {
+  if (c) this.write(c);
+  this.emit('end', this.received);
+};
+
+////////
+
+// tiny node-tap lookalike.
+var tests = [];
+function test(name, fn) {
+  tests.push([name, fn]);
+}
+
+function run() {
+  var next = tests.shift();
+  if (!next)
+    return console.error('ok');
+
+  var name = next[0];
+  var fn = next[1];
+  console.log('# %s', name);
+  fn({
+    same: assert.deepEqual,
+    equal: assert.equal,
+    end: run
+  });
+}
+
+process.nextTick(run);
+
+
+test('a most basic test', function(t) {
+  var r = new TestReader(20);
+
+  var reads = [];
+  var expect = [ 'x',
+                 'xx',
+                 'xxx',
+                 'xxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxxxxx',
+                 'xxxxxxxxx',
+                 'xxx',
+                 'xxxxxxxxxxxx',
+                 'xxxxxxxx',
+                 'xxxxxxxxxxxxxxx',
+                 'xxxxx',
+                 'xxxxxxxxxxxxxxxxxx',
+                 'xx',
+                 'xxxxxxxxxxxxxxxxxxxx',
+                 'xxxxxxxxxxxxxxxxxxxx',
+                 'xxxxxxxxxxxxxxxxxxxx',
+                 'xxxxxxxxxxxxxxxxxxxx',
+                 'xxxxxxxxxxxxxxxxxxxx' ];
+
+  r.on('end', function() {
+    t.same(reads, expect);
+    t.end();
+  });
+
+  var readSize = 1;
+  function flow() {
+    var res;
+    while (null !== (res = r.read(readSize++))) {
+      reads.push(res.toString());
+    }
+    r.once('readable', flow);
+  }
+
+  flow();
+});
+
+test('pipe', function(t) {
+  var r = new TestReader(5);
+
+  var expect = [ 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx' ]
+
+  var w = new TestWriter;
+  var flush = true;
+  w.on('end', function(received) {
+    t.same(received, expect);
+    t.end();
+  });
+
+  r.pipe(w);
+});
+
+
+
+[1,2,3,4,5,6,7,8,9].forEach(function(SPLIT) {
+  test('unpipe', function(t) {
+    var r = new TestReader(5);
+
+    // unpipe after 3 writes, then write to another stream instead.
+    var expect = [ 'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx' ];
+    expect = [ expect.slice(0, SPLIT), expect.slice(SPLIT) ];
+
+    var w = [ new TestWriter(), new TestWriter() ];
+
+    var writes = SPLIT;
+    w[0].on('write', function() {
+      if (--writes === 0) {
+        r.unpipe();
+        w[0].end();
+        r.pipe(w[1]);
+      }
+    });
+
+    var ended = 0;
+
+    w[0].on('end', function(results) {
+      ended++;
+      t.same(results, expect[0]);
+    });
+
+    w[1].on('end', function(results) {
+      ended++;
+      t.equal(ended, 2);
+      t.same(results, expect[1]);
+      t.end();
+    });
+
+    r.pipe(w[0]);
+  });
+});
+
+
+// both writers should get the same exact data.
+test('multipipe', function(t) {
+  var r = new TestReader(5);
+  var w = [ new TestWriter, new TestWriter ];
+
+  var expect = [ 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx',
+                 'xxxxx' ];
+
+  var c = 2;
+  w[0].on('end', function(received) {
+    t.same(received, expect, 'first');
+    if (--c === 0) t.end();
+  });
+  w[1].on('end', function(received) {
+    t.same(received, expect, 'second');
+    if (--c === 0) t.end();
+  });
+
+  r.pipe(w[0]);
+  r.pipe(w[1]);
+});
+
+
+[1,2,3,4,5,6,7,8,9].forEach(function(SPLIT) {
+  test('multi-unpipe', function(t) {
+    var r = new TestReader(5);
+
+    // unpipe after 3 writes, then write to another stream instead.
+    var expect = [ 'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx',
+                   'xxxxx' ];
+    expect = [ expect.slice(0, SPLIT), expect.slice(SPLIT) ];
+
+    var w = [ new TestWriter(), new TestWriter(), new TestWriter() ];
+
+    var writes = SPLIT;
+    w[0].on('write', function() {
+      if (--writes === 0) {
+        r.unpipe();
+        w[0].end();
+        r.pipe(w[1]);
+      }
+    });
+
+    var ended = 0;
+
+    w[0].on('end', function(results) {
+      ended++;
+      t.same(results, expect[0]);
+    });
+
+    w[1].on('end', function(results) {
+      ended++;
+      t.equal(ended, 2);
+      t.same(results, expect[1]);
+      t.end();
+    });
+
+    r.pipe(w[0]);
+    r.pipe(w[2]);
+  });
+});
diff --git a/test/simple/test-stream2-fs.js b/test/simple/test-stream2-fs.js
new file mode 100644
index 00000000000..70cd8ba4de3
--- /dev/null
+++ b/test/simple/test-stream2-fs.js
@@ -0,0 +1,76 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+
+var common = require('../common.js');
+var R = require('_stream_readable');
+var assert = require('assert');
+
+var fs = require('fs');
+var FSReadable = fs.ReadStream;
+
+var path = require('path');
+var file = path.resolve(common.fixturesDir, 'x1024.txt');
+
+var size = fs.statSync(file).size;
+
+// expect to see chunks no more than 10 bytes each.
+var expectLengths = [];
+for (var i = size; i > 0; i -= 10) {
+  expectLengths.push(Math.min(i, 10));
+}
+
+var util = require('util');
+var Stream = require('stream');
+
+util.inherits(TestWriter, Stream);
+
+function TestWriter() {
+  Stream.apply(this);
+  this.buffer = [];
+  this.length = 0;
+}
+
+TestWriter.prototype.write = function(c) {
+  this.buffer.push(c.toString());
+  this.length += c.length;
+  return true;
+};
+
+TestWriter.prototype.end = function(c) {
+  if (c) this.buffer.push(c.toString());
+  this.emit('results', this.buffer);
+}
+
+var r = new FSReadable(file, { bufferSize: 10 });
+var w = new TestWriter();
+
+w.on('results', function(res) {
+  console.error(res, w.length);
+  assert.equal(w.length, size);
+  var l = 0;
+  assert.deepEqual(res.map(function (c) {
+    return c.length;
+  }), expectLengths);
+  console.log('ok');
+});
+
+r.pipe(w, { chunkSize: 10 });
diff --git a/test/simple/test-stream2-readable-from-list.js b/test/simple/test-stream2-readable-from-list.js
new file mode 100644
index 00000000000..a28fe343eec
--- /dev/null
+++ b/test/simple/test-stream2-readable-from-list.js
@@ -0,0 +1,109 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+var assert = require('assert');
+var common = require('../common.js');
+var fromList = require('_stream_readable')._fromList;
+
+// tiny node-tap lookalike.
+var tests = [];
+function test(name, fn) {
+  tests.push([name, fn]);
+}
+
+function run() {
+  var next = tests.shift();
+  if (!next)
+    return console.error('ok');
+
+  var name = next[0];
+  var fn = next[1];
+  console.log('# %s', name);
+  fn({
+    same: assert.deepEqual,
+    equal: assert.equal,
+    end: run
+  });
+}
+
+process.nextTick(run);
+
+
+
+test('buffers', function(t) {
+  // have a length
+  var len = 16;
+  var list = [ new Buffer('foog'),
+               new Buffer('bark'),
+               new Buffer('bazy'),
+               new Buffer('kuel') ];
+
+  // read more than the first element.
+  var ret = fromList(6, list, 16);
+  t.equal(ret.toString(), 'foogba');
+
+  // read exactly the first element.
+  ret = fromList(2, list, 10);
+  t.equal(ret.toString(), 'rk');
+
+  // read less than the first element.
+  ret = fromList(2, list, 8);
+  t.equal(ret.toString(), 'ba');
+
+  // read more than we have.
+  ret = fromList(100, list, 6);
+  t.equal(ret.toString(), 'zykuel');
+
+  // all consumed.
+  t.same(list, []);
+
+  t.end();
+});
+
+test('strings', function(t) {
+  // have a length
+  var len = 16;
+  var list = [ 'foog',
+               'bark',
+               'bazy',
+               'kuel' ];
+
+  // read more than the first element.
+  var ret = fromList(6, list, 16, true);
+  t.equal(ret, 'foogba');
+
+  // read exactly the first element.
+  ret = fromList(2, list, 10, true);
+  t.equal(ret, 'rk');
+
+  // read less than the first element.
+  ret = fromList(2, list, 8, true);
+  t.equal(ret, 'ba');
+
+  // read more than we have.
+  ret = fromList(100, list, 6, true);
+  t.equal(ret, 'zykuel');
+
+  // all consumed.
+  t.same(list, []);
+
+  t.end();
+});
diff --git a/test/simple/test-stream2-set-encoding.js b/test/simple/test-stream2-set-encoding.js
new file mode 100644
index 00000000000..a1883fbbb84
--- /dev/null
+++ b/test/simple/test-stream2-set-encoding.js
@@ -0,0 +1,299 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+
+var common = require('../common.js');
+var assert = require('assert');
+var R = require('_stream_readable');
+var util = require('util');
+
+// tiny node-tap lookalike.
+var tests = [];
+function test(name, fn) {
+  tests.push([name, fn]);
+}
+
+function run() {
+  var next = tests.shift();
+  if (!next)
+    return console.error('ok');
+
+  var name = next[0];
+  var fn = next[1];
+  console.log('# %s', name);
+  fn({
+    same: assert.deepEqual,
+    equal: assert.equal,
+    end: run
+  });
+}
+
+process.nextTick(run);
+
+/////
+
+util.inherits(TestReader, R);
+
+function TestReader(n, opts) {
+  R.call(this, util._extend({
+    bufferSize: 5
+  }, opts));
+
+  this.pos = 0;
+  this.len = n || 100;
+}
+
+TestReader.prototype._read = function(n, cb) {
+  setTimeout(function() {
+
+    if (this.pos >= this.len) {
+      return cb();
+    }
+
+    n = Math.min(n, this.len - this.pos);
+    if (n <= 0) {
+      return cb();
+    }
+
+    this.pos += n;
+    var ret = new Buffer(n);
+    ret.fill('a');
+
+    return cb(null, ret);
+  }.bind(this), 1);
+};
+
+test('setEncoding utf8', function(t) {
+  var tr = new TestReader(100);
+  tr.setEncoding('utf8');
+  var out = [];
+  var expect =
+    [ 'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa' ];
+
+  tr.on('readable', function flow() {
+    var chunk;
+    while (null !== (chunk = tr.read(10)))
+      out.push(chunk);
+  });
+
+  tr.on('end', function() {
+    t.same(out, expect);
+    t.end();
+  });
+
+  // just kick it off.
+  tr.emit('readable');
+});
+
+
+test('setEncoding hex', function(t) {
+  var tr = new TestReader(100);
+  tr.setEncoding('hex');
+  var out = [];
+  var expect =
+    [ '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161' ];
+
+  tr.on('readable', function flow() {
+    var chunk;
+    while (null !== (chunk = tr.read(10)))
+      out.push(chunk);
+  });
+
+  tr.on('end', function() {
+    t.same(out, expect);
+    t.end();
+  });
+
+  // just kick it off.
+  tr.emit('readable');
+});
+
+test('setEncoding hex with read(13)', function(t) {
+  var tr = new TestReader(100);
+  tr.setEncoding('hex');
+  var out = [];
+  var expect =
+    [ "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "16161" ];
+
+  tr.on('readable', function flow() {
+    var chunk;
+    while (null !== (chunk = tr.read(13)))
+      out.push(chunk);
+  });
+
+  tr.on('end', function() {
+    t.same(out, expect);
+    t.end();
+  });
+
+  // just kick it off.
+  tr.emit('readable');
+});
+
+test('encoding: utf8', function(t) {
+  var tr = new TestReader(100, { encoding: 'utf8' });
+  var out = [];
+  var expect =
+    [ 'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa',
+      'aaaaaaaaaa' ];
+
+  tr.on('readable', function flow() {
+    var chunk;
+    while (null !== (chunk = tr.read(10)))
+      out.push(chunk);
+  });
+
+  tr.on('end', function() {
+    t.same(out, expect);
+    t.end();
+  });
+
+  // just kick it off.
+  tr.emit('readable');
+});
+
+
+test('encoding: hex', function(t) {
+  var tr = new TestReader(100, { encoding: 'hex' });
+  var out = [];
+  var expect =
+    [ '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161',
+      '6161616161' ];
+
+  tr.on('readable', function flow() {
+    var chunk;
+    while (null !== (chunk = tr.read(10)))
+      out.push(chunk);
+  });
+
+  tr.on('end', function() {
+    t.same(out, expect);
+    t.end();
+  });
+
+  // just kick it off.
+  tr.emit('readable');
+});
+
+test('encoding: hex with read(13)', function(t) {
+  var tr = new TestReader(100, { encoding: 'hex' });
+  var out = [];
+  var expect =
+    [ "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "1616161616161",
+      "6161616161616",
+      "16161" ];
+
+  tr.on('readable', function flow() {
+    var chunk;
+    while (null !== (chunk = tr.read(13)))
+      out.push(chunk);
+  });
+
+  tr.on('end', function() {
+    t.same(out, expect);
+    t.end();
+  });
+
+  // just kick it off.
+  tr.emit('readable');
+});
diff --git a/test/simple/test-stream2-transform.js b/test/simple/test-stream2-transform.js
new file mode 100644
index 00000000000..9b6365b5ca9
--- /dev/null
+++ b/test/simple/test-stream2-transform.js
@@ -0,0 +1,309 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+var assert = require('assert');
+var common = require('../common.js');
+var PassThrough = require('_stream_passthrough');
+var Transform = require('_stream_transform');
+
+// tiny node-tap lookalike.
+var tests = [];
+function test(name, fn) {
+  tests.push([name, fn]);
+}
+
+function run() {
+  var next = tests.shift();
+  if (!next)
+    return console.error('ok');
+
+  var name = next[0];
+  var fn = next[1];
+  console.log('# %s', name);
+  fn({
+    same: assert.deepEqual,
+    equal: assert.equal,
+    end: run
+  });
+}
+
+process.nextTick(run);
+
+/////
+
+test('passthrough', function(t) {
+  var pt = new PassThrough();
+
+  pt.write(new Buffer('foog'));
+  pt.write(new Buffer('bark'));
+  pt.write(new Buffer('bazy'));
+  pt.write(new Buffer('kuel'));
+  pt.end();
+
+  t.equal(pt.read(5).toString(), 'foogb');
+  t.equal(pt.read(5).toString(), 'arkba');
+  t.equal(pt.read(5).toString(), 'zykue');
+  t.equal(pt.read(5).toString(), 'l');
+  t.end();
+});
+
+test('simple transform', function(t) {
+  var pt = new Transform;
+  pt._transform = function(c, output, cb) {
+    var ret = new Buffer(c.length);
+    ret.fill('x');
+    output(ret);
+    cb();
+  };
+
+  pt.write(new Buffer('foog'));
+  pt.write(new Buffer('bark'));
+  pt.write(new Buffer('bazy'));
+  pt.write(new Buffer('kuel'));
+  pt.end();
+
+  t.equal(pt.read(5).toString(), 'xxxxx');
+  t.equal(pt.read(5).toString(), 'xxxxx');
+  t.equal(pt.read(5).toString(), 'xxxxx');
+  t.equal(pt.read(5).toString(), 'x');
+  t.end();
+});
+
+test('async passthrough', function(t) {
+  var pt = new Transform;
+  pt._transform = function(chunk, output, cb) {
+    setTimeout(function() {
+      output(chunk);
+      cb();
+    }, 10);
+  };
+
+  pt.write(new Buffer('foog'));
+  pt.write(new Buffer('bark'));
+  pt.write(new Buffer('bazy'));
+  pt.write(new Buffer('kuel'));
+  pt.end();
+
+  setTimeout(function() {
+    t.equal(pt.read(5).toString(), 'foogb');
+    t.equal(pt.read(5).toString(), 'arkba');
+    t.equal(pt.read(5).toString(), 'zykue');
+    t.equal(pt.read(5).toString(), 'l');
+    t.end();
+  }, 100);
+});
+
+test('assymetric transform (expand)', function(t) {
+  var pt = new Transform;
+
+  // emit each chunk 2 times.
+  pt._transform = function(chunk, output, cb) {
+    setTimeout(function() {
+      output(chunk);
+      setTimeout(function() {
+        output(chunk);
+        cb();
+      }, 10)
+    }, 10);
+  };
+
+  pt.write(new Buffer('foog'));
+  pt.write(new Buffer('bark'));
+  pt.write(new Buffer('bazy'));
+  pt.write(new Buffer('kuel'));
+  pt.end();
+
+  setTimeout(function() {
+    t.equal(pt.read(5).toString(), 'foogf');
+    t.equal(pt.read(5).toString(), 'oogba');
+    t.equal(pt.read(5).toString(), 'rkbar');
+    t.equal(pt.read(5).toString(), 'kbazy');
+    t.equal(pt.read(5).toString(), 'bazyk');
+    t.equal(pt.read(5).toString(), 'uelku');
+    t.equal(pt.read(5).toString(), 'el');
+    t.end();
+  }, 100);
+});
+
+test('assymetric transform (compress)', function(t) {
+  var pt = new Transform;
+
+  // each output is the first char of 3 consecutive chunks,
+  // or whatever's left.
+  pt.state = '';
+
+  pt._transform = function(chunk, output, cb) {
+    if (!chunk)
+      chunk = '';
+    var s = chunk.toString();
+    setTimeout(function() {
+      this.state += s.charAt(0);
+      if (this.state.length === 3) {
+        output(new Buffer(this.state));
+        this.state = '';
+      }
+      cb();
+    }.bind(this), 10);
+  };
+
+  pt._flush = function(output, cb) {
+    // just output whatever we have.
+    setTimeout(function() {
+      output(new Buffer(this.state));
+      this.state = '';
+      cb();
+    }.bind(this), 10);
+  };
+
+  pt._writableState.lowWaterMark = 3;
+
+  pt.write(new Buffer('aaaa'));
+  pt.write(new Buffer('bbbb'));
+  pt.write(new Buffer('cccc'));
+  pt.write(new Buffer('dddd'));
+  pt.write(new Buffer('eeee'));
+  pt.write(new Buffer('aaaa'));
+  pt.write(new Buffer('bbbb'));
+  pt.write(new Buffer('cccc'));
+  pt.write(new Buffer('dddd'));
+  pt.write(new Buffer('eeee'));
+  pt.write(new Buffer('aaaa'));
+  pt.write(new Buffer('bbbb'));
+  pt.write(new Buffer('cccc'));
+  pt.write(new Buffer('dddd'));
+  pt.end();
+
+  // 'abcdeabcdeabcd'
+  setTimeout(function() {
+    t.equal(pt.read(5).toString(), 'abcde');
+    t.equal(pt.read(5).toString(), 'abcde');
+    t.equal(pt.read(5).toString(), 'abcd');
+    t.end();
+  }, 200);
+});
+
+
+test('passthrough event emission', function(t) {
+  var pt = new PassThrough({
+    lowWaterMark: 0
+  });
+  var emits = 0;
+  pt.on('readable', function() {
+    var state = pt._readableState;
+    console.error('>>> emit readable %d', emits);
+    emits++;
+  });
+
+  var i = 0;
+
+  pt.write(new Buffer('foog'));
+  pt.write(new Buffer('bark'));
+
+  t.equal(pt.read(5).toString(), 'foogb');
+  t.equal(pt.read(5) + '', 'null');
+
+  console.error('need emit 0');
+
+  pt.write(new Buffer('bazy'));
+  pt.write(new Buffer('kuel'));
+
+  console.error('should have emitted readable now');
+  t.equal(emits, 1);
+
+  t.equal(pt.read(5).toString(), 'arkba');
+  t.equal(pt.read(5).toString(), 'zykue');
+  t.equal(pt.read(5), null);
+
+  console.error('need emit 1');
+
+  pt.end();
+
+  t.equal(emits, 2);
+
+  t.equal(pt.read(5).toString(), 'l');
+  t.equal(pt.read(5), null);
+
+  console.error('should not have emitted again');
+  t.equal(emits, 2);
+  t.end();
+});
+
+test('passthrough event emission reordered', function(t) {
+  var pt = new PassThrough;
+  var emits = 0;
+  pt.on('readable', function() {
+    console.error('emit readable', emits)
+    emits++;
+  });
+
+  pt.write(new Buffer('foog'));
+  pt.write(new Buffer('bark'));
+
+  t.equal(pt.read(5).toString(), 'foogb');
+  t.equal(pt.read(5), null);
+
+  console.error('need emit 0');
+  pt.once('readable', function() {
+    t.equal(pt.read(5).toString(), 'arkba');
+    t.equal(pt.read(5).toString(), 'zykue');
+    t.equal(pt.read(5), null);
+
+    console.error('need emit 1');
+    pt.once('readable', function() {
+      t.equal(pt.read(5).toString(), 'l');
+      t.equal(pt.read(5), null);
+
+      t.equal(emits, 2);
+      t.end();
+    });
+    pt.end();
+  });
+  pt.write(new Buffer('bazy'));
+  pt.write(new Buffer('kuel'));
+});
+
+test('passthrough facaded', function(t) {
+  console.error('passthrough facaded');
+  var pt = new PassThrough;
+  var datas = [];
+  pt.on('data', function(chunk) {
+    datas.push(chunk.toString());
+  });
+
+  pt.on('end', function() {
+    t.same(datas, ['foog', 'bark', 'bazy', 'kuel']);
+    t.end();
+  });
+
+  pt.write(new Buffer('foog'));
+  setTimeout(function() {
+    pt.write(new Buffer('bark'));
+    setTimeout(function() {
+      pt.write(new Buffer('bazy'));
+      setTimeout(function() {
+        pt.write(new Buffer('kuel'));
+        setTimeout(function() {
+          pt.end();
+        }, 10);
+      }, 10);
+    }, 10);
+  }, 10);
+});
diff --git a/test/simple/test-stream2-writable.js b/test/simple/test-stream2-writable.js
new file mode 100644
index 00000000000..bc1859ce222
--- /dev/null
+++ b/test/simple/test-stream2-writable.js
@@ -0,0 +1,142 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+var common = require('../common.js');
+var W = require('_stream_writable');
+var assert = require('assert');
+
+var util = require('util');
+util.inherits(TestWriter, W);
+
+function TestWriter() {
+  W.apply(this, arguments);
+  this.buffer = [];
+  this.written = 0;
+}
+
+TestWriter.prototype._write = function(chunk, cb) {
+  // simulate a small unpredictable latency
+  setTimeout(function() {
+    this.buffer.push(chunk.toString());
+    this.written += chunk.length;
+    cb();
+  }.bind(this), Math.floor(Math.random() * 10));
+};
+
+var chunks = new Array(50);
+for (var i = 0; i < chunks.length; i++) {
+  chunks[i] = new Array(i + 1).join('x');
+}
+
+// tiny node-tap lookalike.
+var tests = [];
+function test(name, fn) {
+  tests.push([name, fn]);
+}
+
+function run() {
+  var next = tests.shift();
+  if (!next)
+    return console.log('ok');
+
+  var name = next[0];
+  var fn = next[1];
+  console.log('# %s', name);
+  fn({
+    same: assert.deepEqual,
+    equal: assert.equal,
+    end: run
+  });
+}
+
+process.nextTick(run);
+
+test('write fast', function(t) {
+  var tw = new TestWriter({
+    lowWaterMark: 5,
+    highWaterMark: 100
+  });
+
+  tw.on('finish', function() {
+    t.same(tw.buffer, chunks, 'got chunks in the right order');
+    t.end();
+  });
+
+  chunks.forEach(function(chunk) {
+    // screw backpressure.  Just buffer it all up.
+    tw.write(chunk);
+  });
+  tw.end();
+});
+
+test('write slow', function(t) {
+  var tw = new TestWriter({
+    lowWaterMark: 5,
+    highWaterMark: 100
+  });
+
+  tw.on('finish', function() {
+    t.same(tw.buffer, chunks, 'got chunks in the right order');
+    t.end();
+  });
+
+  var i = 0;
+  (function W() {
+    tw.write(chunks[i++]);
+    if (i < chunks.length)
+      setTimeout(W, 10);
+    else
+      tw.end();
+  })();
+});
+
+test('write backpressure', function(t) {
+  var tw = new TestWriter({
+    lowWaterMark: 5,
+    highWaterMark: 50
+  });
+
+  var drains = 0;
+
+  tw.on('finish', function() {
+    t.same(tw.buffer, chunks, 'got chunks in the right order');
+    t.equal(drains, 17);
+    t.end();
+  });
+
+  tw.on('drain', function() {
+    drains++;
+  });
+
+  var i = 0;
+  (function W() {
+    do {
+      var ret = tw.write(chunks[i++]);
+    } while (ret !== false && i < chunks.length);
+
+    if (i < chunks.length) {
+      assert(tw._writableState.length >= 50);
+      tw.once('drain', W);
+    } else {
+      tw.end();
+    }
+  })();
+});