diff --git a/.travis.yml b/.travis.yml
index e526ffa..c2ffb26 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,5 @@
 language: node_js
 node_js:
-  - '6'
-  - '4'
-  - '0.12'
-  - '0.10'
+  - '12'
+  - '14'
+  - '16'
diff --git a/appveyor.yml b/appveyor.yml
index d4b9843..fae1753 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -3,10 +3,9 @@
 # Test against these versions of Node.js.
 environment:
   matrix:
-    - nodejs_version: '6'
-    - nodejs_version: '4'
-    - nodejs_version: '0.12'
-    - nodejs_version: '0.10'
+    - nodejs_version: '12'
+    - nodejs_version: '14'
+    - nodejs_version: '16'
 
 # Install scripts. (runs after repo cloning)
 install:
diff --git a/index.js b/index.js
index 95a0aef..249995e 100644
--- a/index.js
+++ b/index.js
@@ -15,7 +15,7 @@
  * responsible for uncompressing in that case if necessary).
  */
 
-exports.Reader = require('./lib/reader');
+exports.Reader = require('./lib/reader.js');
 
 /**
  * The `Writer` class outputs a valid WAVE file from the audio data written to
@@ -26,7 +26,7 @@ exports.Reader = require('./lib/reader');
  * written.
  */
 
-exports.Writer = require('./lib/writer');
+exports.Writer = require('./lib/writer.js');
 
 /**
  * The `FileWriter` is a subclass of `Writer` that automatically takes care of
@@ -34,4 +34,4 @@ exports.Writer = require('./lib/writer');
  * output file.
  */
 
-exports.FileWriter = require('./lib/file-writer');
+exports.FileWriter = require('./lib/file-writer.js');
diff --git a/lib/file-writer.js b/lib/file-writer.js
index aa0c916..c21e81b 100644
--- a/lib/file-writer.js
+++ b/lib/file-writer.js
@@ -4,14 +4,7 @@
  */
 
 var fs = require('fs');
-var Writer = require('./writer');
-var inherits = require('util').inherits;
-
-/**
- * Module exports.
- */
-
-module.exports = FileWriter;
+var Writer = require('./writer.js');
 
 /**
  * The `FileWriter` class.
@@ -21,45 +14,54 @@ module.exports = FileWriter;
  * @api public
  */
 
-function FileWriter (path, opts) {
-  if (!(this instanceof FileWriter)) return new FileWriter(path, opts);
-  Writer.call(this, opts);
-  this.path = path;
-  this.file = fs.createWriteStream(path, opts);
-  this.pipe(this.file);
-  this.on('header', this._onHeader);
-}
-inherits(FileWriter, Writer);
+class FileWriter extends Writer {
+  constructor (path, opts) {
+    super(opts);
+    this.path = path;
+    this.file = fs.createWriteStream(path, opts);
+    this.pipe(this.file);
+    this.on('header', this._onHeader);
+  }
 
-/**
- * Writes the updated WAVE header to the beginning of the file.
- * Emits a "done" event when everything is all good.
- *
- * @api private
- */
+  /**
+   * Writes the updated WAVE header to the beginning of the file.
+   * Emits a "done" event when everything is all good.
+   *
+   * @api private
+   */
+  _onHeader(header) {
+    var self = this;
+    var fd;
 
-FileWriter.prototype._onHeader = function (header) {
-  var self = this;
-  var fd;
+    function onOpen(err, f) {
+      if (err)
+        return self.emit('error', err);
+      fd = f;
+      fs.write(fd, header, 0, header.length, 0, onWrite);
+    }
 
-  function onOpen (err, f) {
-    if (err) return self.emit('error', err);
-    fd = f;
-    fs.write(fd, header, 0, header.length, 0, onWrite);
-  }
+    function onWrite(err, bytesWritten) {
+      if (err)
+        return self.emit('error', err);
+      if (bytesWritten !== header.length) {
+        return self.emit('error', new Error('problem writing "header" data'));
+      }
+      fs.close(fd, onClose);
+    }
 
-  function onWrite (err, bytesWritten) {
-    if (err) return self.emit('error', err);
-    if (bytesWritten !== header.length) {
-      return self.emit('error', new Error('problem writing "header" data'));
+    function onClose(err) {
+      if (err)
+        return self.emit('error', err);
+      self.emit('done');
     }
-    fs.close(fd, onClose);
-  }
 
-  function onClose (err) {
-    if (err) return self.emit('error', err);
-    self.emit('done');
+    fs.open(self.path, 'r+', onOpen);
   }
+}
+
+
+/**
+ * Module exports.
+ */
 
-  fs.open(self.path, 'r+', onOpen);
-};
+module.exports = FileWriter;
\ No newline at end of file
diff --git a/lib/reader.js b/lib/reader.js
index 9a90f1f..cb1ba38 100644
--- a/lib/reader.js
+++ b/lib/reader.js
@@ -3,12 +3,10 @@
  * Module dependencies.
  */
 
-var util = require('util');
+var { format: f } = require('util');
+var { Transform } = require('stream');
 var Parser = require('stream-parser');
-var Transform = require('readable-stream/transform');
 var debug = require('debug')('wave:reader');
-var inherits = util.inherits;
-var f = util.format;
 
 /**
  * Values for the `audioFormat` byte.
@@ -26,12 +24,6 @@ var formats = {
   WAVE_FORMAT_EXTENSIBLE: 0xFFFE // Determined by SubFormat
 };
 
-/**
- * Module exports.
- */
-
-module.exports = Reader;
-
 /**
  * The `Reader` class accepts a WAV audio file written to it and outputs the raw
  * audio data with the WAV header stripped (most of the time, PCM audio data will
@@ -43,197 +35,202 @@ module.exports = Reader;
  * @api public
  */
 
-function Reader (opts) {
-  if (!(this instanceof Reader)) {
-    return new Reader(opts);
+class Reader extends Transform {
+  constructor (opts) {
+    super(opts);
+
+    this._bytes(4, this._onRiffID);
   }
-  Transform.call(this, opts);
 
-  this._bytes(4, this._onRiffID);
-}
-inherits(Reader, Transform);
+  // the beginning of the WAV file
+  _onRiffID(chunk) {
+    debug('onRiffID: %o', chunk);
+    var id = this.riffId = chunk.toString('ascii');
+    if (id === 'RIFF') {
+      debug('detected little-endian WAVE file');
+      this.endianness = 'LE';
+      this._bytes(4, this._onChunkSize);
+    } else if (id === 'RIFX') {
+      debug('detected big-endian WAVE file');
+      this.endianness = 'BE';
+      this._bytes(4, this._onChunkSize);
+    } else {
+      this.emit('error', new Error(f('bad "chunk id": expected "RIFF" or "RIFX", got %j', id)));
+    }
+  }
 
-/**
- * Mixin `Parser`.
- */
+  // size of the WAV
+  _onChunkSize(chunk) {
+    debug('onChunkSize: %o', chunk);
+    this.chunkSize = chunk['readUInt32' + this.endianness](0);
+    this._bytes(4, this._onFormat);
+  }
 
-Parser(Reader.prototype);
+  // the RIFF "format", should always be "WAVE"
+  _onFormat(chunk) {
+    debug('onFormat: %o', chunk);
+    this.waveId = chunk.toString('ascii');
+    if (this.waveId === 'WAVE') {
+      this._bytes(4, this._onSubchunk1ID);
+    } else {
+      this.emit('error', new Error(f('bad "format": expected "WAVE", got %j', this.waveId)));
+    }
+  }
 
-// the beginning of the WAV file
-Reader.prototype._onRiffID = function (chunk) {
-  debug('onRiffID: %o', chunk);
-  var id = this.riffId = chunk.toString('ascii');
-  if (id === 'RIFF') {
-    debug('detected little-endian WAVE file');
-    this.endianness = 'LE';
-    this._bytes(4, this._onChunkSize);
-  } else if (id === 'RIFX') {
-    debug('detected big-endian WAVE file');
-    this.endianness = 'BE';
-    this._bytes(4, this._onChunkSize);
-  } else {
-    this.emit('error', new Error(f('bad "chunk id": expected "RIFF" or "RIFX", got %j', id)));
+  // size of the "subchunk1" (the header)
+  _onSubchunk1ID(chunk) {
+    debug('onSubchunk1ID: %o', chunk);
+    var subchunk1ID = chunk.toString('ascii');
+    this.chunkId = subchunk1ID;
+    if (subchunk1ID === 'fmt ') {
+      this._bytes(4, this._onSubchunk1Size);
+    } else {
+      this.emit('error', new Error(f('bad "fmt id": expected "fmt ", got %j', subchunk1ID)));
+    }
   }
-};
 
-// size of the WAV
-Reader.prototype._onChunkSize = function (chunk) {
-  debug('onChunkSize: %o', chunk);
-  this.chunkSize = chunk['readUInt32' + this.endianness](0);
-  this._bytes(4, this._onFormat);
-};
+  _onSubchunk1Size(chunk) {
+    debug('onSubchunk1Size: %o', chunk);
+    this.subchunk1Size = chunk['readUInt32' + this.endianness](0);
+    // TODO: assert should be 16 for PCM
+    this._bytes(this.subchunk1Size, this._onSubchunk1);
+  }
 
-// the RIFF "format", should always be "WAVE"
-Reader.prototype._onFormat = function (chunk) {
-  debug('onFormat: %o', chunk);
-  this.waveId = chunk.toString('ascii');
-  if (this.waveId === 'WAVE') {
-    this._bytes(4, this._onSubchunk1ID);
-  } else {
-    this.emit('error', new Error(f('bad "format": expected "WAVE", got %j', this.waveId)));
+  _onSubchunk1(chunk) {
+    debug('onSubchunk1: %o', chunk);
+    this.audioFormat = chunk['readUInt16' + this.endianness](0);
+    this.channels = chunk['readUInt16' + this.endianness](2);
+    this.sampleRate = chunk['readUInt32' + this.endianness](4);
+    this.byteRate = chunk['readUInt32' + this.endianness](8); // useless...
+    this.blockAlign = chunk['readUInt16' + this.endianness](12); // useless...
+    this.bitDepth = chunk['readUInt16' + this.endianness](14);
+    this.signed = this.bitDepth !== 8;
+
+    var format = {
+      audioFormat: this.audioFormat,
+      endianness: this.endianness,
+      channels: this.channels,
+      sampleRate: this.sampleRate,
+      byteRate: this.byteRate,
+      blockAlign: this.blockAlign,
+      bitDepth: this.bitDepth,
+      signed: this.signed
+    };
+
+    switch (format.audioFormat) {
+      case formats.WAVE_FORMAT_PCM:
+        // default, common case. don't need to do anything.
+        break;
+      case formats.WAVE_FORMAT_IEEE_FLOAT:
+        format.float = true;
+        break;
+      case formats.WAVE_FORMAT_ALAW:
+        format.alaw = true;
+        break;
+      case formats.WAVE_FORMAT_MULAW:
+        format.ulaw = true;
+        break;
+    }
+
+    this.emit('format', format);
+
+    this._bytes(4, this._onSubchunk2ID);
   }
-};
 
-// size of the "subchunk1" (the header)
-Reader.prototype._onSubchunk1ID = function (chunk) {
-  debug('onSubchunk1ID: %o', chunk);
-  var subchunk1ID = chunk.toString('ascii');
-  this.chunkId = subchunk1ID;
-  if (subchunk1ID === 'fmt ') {
-    this._bytes(4, this._onSubchunk1Size);
-  } else {
-    this.emit('error', new Error(f('bad "fmt id": expected "fmt ", got %j', subchunk1ID)));
+  _onSubchunk2ID(chunk) {
+    debug('onSubchunk2ID: %o', chunk);
+    var subchunk2ID = chunk.toString('ascii');
+
+    if (subchunk2ID === 'data') {
+      // Data Chunk - "data"
+      this._bytes(4, this._onDataChunkSize);
+    } else if (subchunk2ID === 'fact') {
+      // Fact Chunk - "fact"
+      this._bytes(4, this._onFactChunkSize);
+    } else {
+      // Unknown Chunk - parse it an emit a "chunk" event
+      debug('parsing unknown %o chunk', subchunk2ID);
+      this.unknownID = subchunk2ID;
+      this._bytes(4, this._onUnknownChunkSize);
+    }
   }
-};
 
-Reader.prototype._onSubchunk1Size = function (chunk) {
-  debug('onSubchunk1Size: %o', chunk);
-  this.subchunk1Size = chunk['readUInt32' + this.endianness](0);
-  // TODO: assert should be 16 for PCM
-  this._bytes(this.subchunk1Size, this._onSubchunk1);
-};
+  // size of the remaining data in this WAV file
+  _onDataChunkSize(chunk) {
+    debug('onDataChunkSize: %o', chunk);
+    var chunkSize = chunk['readUInt32' + this.endianness](0);
 
-Reader.prototype._onSubchunk1 = function (chunk) {
-  debug('onSubchunk1: %o', chunk);
-  this.audioFormat = chunk['readUInt16' + this.endianness](0);
-  this.channels = chunk['readUInt16' + this.endianness](2);
-  this.sampleRate = chunk['readUInt32' + this.endianness](4);
-  this.byteRate = chunk['readUInt32' + this.endianness](8); // useless...
-  this.blockAlign = chunk['readUInt16' + this.endianness](12); // useless...
-  this.bitDepth = chunk['readUInt16' + this.endianness](14);
-  this.signed = this.bitDepth !== 8;
-
-  var format = {
-    audioFormat: this.audioFormat,
-    endianness: this.endianness,
-    channels: this.channels,
-    sampleRate: this.sampleRate,
-    byteRate: this.byteRate,
-    blockAlign: this.blockAlign,
-    bitDepth: this.bitDepth,
-    signed: this.signed
-  };
-
-  switch (format.audioFormat) {
-    case formats.WAVE_FORMAT_PCM:
-      // default, common case. don't need to do anything.
-      break;
-    case formats.WAVE_FORMAT_IEEE_FLOAT:
-      format.float = true;
-      break;
-    case formats.WAVE_FORMAT_ALAW:
-      format.alaw = true;
-      break;
-    case formats.WAVE_FORMAT_MULAW:
-      format.ulaw = true;
-      break;
-  }
+    if (chunkSize === 0) {
+      // Some encoders write `0` for the byte length here in the case of a WAV file
+      // being generated on-the-fly. In that case, we're just gonna passthrough the
+      // remaining bytes assuming they're going to be audio data.
+      chunkSize = Infinity;
+    }
 
-  this.emit('format', format);
+    this._passthrough(chunkSize, this._onDataChunkDone);
+  }
 
-  this._bytes(4, this._onSubchunk2ID);
-};
+  _onDataChunkDone() {
+    debug('onFactChunkDone');
+    // now we're done with the "data" chunk so read a new "chunk ID" to figure out
+    // what's next
+    this._bytes(4, this._onSubchunk2ID);
+  }
 
-Reader.prototype._onSubchunk2ID = function (chunk) {
-  debug('onSubchunk2ID: %o', chunk);
-  var subchunk2ID = chunk.toString('ascii');
-
-  if (subchunk2ID === 'data') {
-    // Data Chunk - "data"
-    this._bytes(4, this._onDataChunkSize);
-  } else if (subchunk2ID === 'fact') {
-    // Fact Chunk - "fact"
-    this._bytes(4, this._onFactChunkSize);
-  } else {
-    // Unknown Chunk - parse it an emit a "chunk" event
-    debug('parsing unknown %o chunk', subchunk2ID);
-    this.unknownID = subchunk2ID;
-    this._bytes(4, this._onUnknownChunkSize);
+  _onFactChunkSize(chunk) {
+    debug('onFactChunkSize: %o', chunk);
+    var chunkDataSize = chunk['readUInt32' + this.endianness](0);
+    this._bytes(chunkDataSize, this._onFactChunkData);
   }
-};
 
-// size of the remaining data in this WAV file
-Reader.prototype._onDataChunkSize = function (chunk) {
-  debug('onDataChunkSize: %o', chunk);
-  var chunkSize = chunk['readUInt32' + this.endianness](0);
+  _onFactChunkData(chunk) {
+    debug('onFactChunkData: %o', chunk);
+    // There is currently only one field defined for the format dependant data.
+    // It is a single 4-byte value that specifies the number of samples in the
+    // waveform data chunk.
+    //
+    // The number of samples field is redundant for sampled data, since the Data
+    // chunk indicates the length of the data. The number of samples can be
+    // determined from the length of the data and the container size as determined
+    // from the Format chunk.
+    var numSamples = chunk['readUInt32' + this.endianness](0);
+    debug('number of samples: %o', numSamples);
+    this.numSamples = numSamples;
+
+    // now we're done with the "fact" chunk so read a new "chunk ID" to figure out
+    // what's next
+    this._bytes(4, this._onSubchunk2ID);
+  }
 
-  if (chunkSize === 0) {
-    // Some encoders write `0` for the byte length here in the case of a WAV file
-    // being generated on-the-fly. In that case, we're just gonna passthrough the
-    // remaining bytes assuming they're going to be audio data.
-    chunkSize = Infinity;
+  _onUnknownChunkSize(chunk) {
+    debug('onUnknownChunkSize: %o', chunk);
+    var chunkSize = chunk['readUInt32' + this.endianness](0);
+    this._bytes(chunkSize, this._onUnknownChunkData);
   }
 
-  this._passthrough(chunkSize, this._onDataChunkDone);
-};
+  _onUnknownChunkData(chunk) {
+    debug('onUnknownChunkData: %o', chunk);
 
-Reader.prototype._onDataChunkDone = function () {
-  debug('onFactChunkDone');
-  // now we're done with the "data" chunk so read a new "chunk ID" to figure out
-  // what's next
-  this._bytes(4, this._onSubchunk2ID);
-};
+    this.emit('chunk', {
+      id: this.unknownID,
+      data: chunk
+    });
 
-Reader.prototype._onFactChunkSize = function (chunk) {
-  debug('onFactChunkSize: %o', chunk);
-  var chunkDataSize = chunk['readUInt32' + this.endianness](0);
-  this._bytes(chunkDataSize, this._onFactChunkData);
-};
+    // now we're done with the "unknown" chunk so read a new "chunk ID" to figure
+    // out what's next
+    this._bytes(4, this._onSubchunk2ID);
+  }
+}
 
-Reader.prototype._onFactChunkData = function (chunk) {
-  debug('onFactChunkData: %o', chunk);
-  // There is currently only one field defined for the format dependant data.
-  // It is a single 4-byte value that specifies the number of samples in the
-  // waveform data chunk.
-  //
-  // The number of samples field is redundant for sampled data, since the Data
-  // chunk indicates the length of the data. The number of samples can be
-  // determined from the length of the data and the container size as determined
-  // from the Format chunk.
-  var numSamples = chunk['readUInt32' + this.endianness](0);
-  debug('number of samples: %o', numSamples);
-  this.numSamples = numSamples;
-
-  // now we're done with the "fact" chunk so read a new "chunk ID" to figure out
-  // what's next
-  this._bytes(4, this._onSubchunk2ID);
-};
+/**
+ * Mixin `Parser`.
+ */
 
-Reader.prototype._onUnknownChunkSize = function (chunk) {
-  debug('onUnknownChunkSize: %o', chunk);
-  var chunkSize = chunk['readUInt32' + this.endianness](0);
-  this._bytes(chunkSize, this._onUnknownChunkData);
-};
+Parser(Reader.prototype);
 
-Reader.prototype._onUnknownChunkData = function (chunk) {
-  debug('onUnknownChunkData: %o', chunk);
 
-  this.emit('chunk', {
-    id: this.unknownID,
-    data: chunk
-  });
+/**
+ * Module exports.
+ */
 
-  // now we're done with the "unknown" chunk so read a new "chunk ID" to figure
-  // out what's next
-  this._bytes(4, this._onSubchunk2ID);
-};
+module.exports = Reader;
\ No newline at end of file
diff --git a/lib/writer.js b/lib/writer.js
index 49a9e1d..026fc72 100644
--- a/lib/writer.js
+++ b/lib/writer.js
@@ -2,18 +2,9 @@
 /**
  * Module dependencies.
  */
-
-var inherits = require('util').inherits;
-var Transform = require('readable-stream/transform');
+var { Transform } = require('stream');
+var { Buffer } = require('buffer');
 var debug = require('debug')('wave:writer');
-var bufferAlloc = require('buffer-alloc');
-var bufferFrom = require('buffer-from');
-
-/**
- * Module exports.
- */
-
-module.exports = Writer;
 
 /**
  * RIFF Chunk IDs in Buffers.
@@ -21,10 +12,10 @@ module.exports = Writer;
  * @api private
  */
 
-var RIFF = bufferFrom('RIFF');
-var WAVE = bufferFrom('WAVE');
-var fmt = bufferFrom('fmt ');
-var data = bufferFrom('data');
+var RIFF = Buffer.from('RIFF');
+var WAVE = Buffer.from('WAVE');
+var fmt = Buffer.from('fmt ');
+var data = Buffer.from('data');
 
 /**
  * The max size of the "data" chunk of a WAVE file. This is the max unsigned
@@ -58,182 +49,185 @@ var MAX_WAV = 4294967295 - 100;
  * @api public
  */
 
-function Writer (opts) {
-  if (!(this instanceof Writer)) {
-    return new Writer(opts);
+class Writer extends Transform {
+  constructor (opts) {
+    super(opts);
+
+    // TODO: allow/properly handle other WAVE audio formats
+    this.endianness = 'LE';
+    this.format = 1; // raw PCM
+    this.channels = 2;
+    this.sampleRate = 44100;
+    this.bitDepth = 16;
+    this.bytesProcessed = 0;
+
+    if (opts) {
+      if (opts.format != null)
+        this.format = opts.format;
+      if (opts.channels != null)
+        this.channels = opts.channels;
+      if (opts.sampleRate != null)
+        this.sampleRate = opts.sampleRate;
+      if (opts.bitDepth != null)
+        this.bitDepth = opts.bitDepth;
+    }
+
+    this._writeHeader();
   }
-  Transform.call(this, opts);
-
-  // TODO: allow/properly handle other WAVE audio formats
-  this.endianness = 'LE';
-  this.format = 1; // raw PCM
-  this.channels = 2;
-  this.sampleRate = 44100;
-  this.bitDepth = 16;
-  this.bytesProcessed = 0;
-
-  if (opts) {
-    if (opts.format != null) this.format = opts.format;
-    if (opts.channels != null) this.channels = opts.channels;
-    if (opts.sampleRate != null) this.sampleRate = opts.sampleRate;
-    if (opts.bitDepth != null) this.bitDepth = opts.bitDepth;
-  }
-
-  this._writeHeader();
-}
-inherits(Writer, Transform);
-
-/**
- * Writes the WAVE header.
- *
- * @api private
- */
-
-Writer.prototype._writeHeader = function () {
-  debug('_writeHeader()');
 
-  // TODO: 44 is only for format 1 (PCM), any other
-  // format will have a variable size...
-  var headerLength = 44;
-
-  var dataLength = this.dataLength;
-  if (dataLength == null) {
-    debug('using default "dataLength" of %d', MAX_WAV);
-    dataLength = MAX_WAV;
-  }
-  var fileSize = dataLength + headerLength;
-  var header = bufferAlloc(headerLength);
-  var offset = 0;
-
-  // write the "RIFF" identifier
-  RIFF.copy(header, offset);
-  offset += RIFF.length;
-
-  // write the file size minus the identifier and this 32-bit int
-  header['writeUInt32' + this.endianness](fileSize - 8, offset);
-  offset += 4;
-
-  // write the "WAVE" identifier
-  WAVE.copy(header, offset);
-  offset += WAVE.length;
-
-  // write the "fmt " sub-chunk identifier
-  fmt.copy(header, offset);
-  offset += fmt.length;
-
-  // write the size of the "fmt " chunk
-  // XXX: value of 16 is hard-coded for raw PCM format. other formats have
-  // different size.
-  header['writeUInt32' + this.endianness](16, offset);
-  offset += 4;
-
-  // write the audio format code
-  header['writeUInt16' + this.endianness](this.format, offset);
-  offset += 2;
-
-  // write the number of channels
-  header['writeUInt16' + this.endianness](this.channels, offset);
-  offset += 2;
-
-  // write the sample rate
-  header['writeUInt32' + this.endianness](this.sampleRate, offset);
-  offset += 4;
-
-  // write the byte rate
-  var byteRate = this.byteRate;
-  if (byteRate == null) {
-    byteRate = this.sampleRate * this.channels * this.bitDepth / 8;
+  /**
+   * Writes the WAVE header.
+   *
+   * @api private
+   */
+  _writeHeader() {
+    debug('_writeHeader()');
+
+    // TODO: 44 is only for format 1 (PCM), any other
+    // format will have a variable size...
+    var headerLength = 44;
+
+    var dataLength = this.dataLength;
+    if (dataLength == null) {
+      debug('using default "dataLength" of %d', MAX_WAV);
+      dataLength = MAX_WAV;
+    }
+    var fileSize = dataLength + headerLength;
+    var header = Buffer.alloc(headerLength);
+    var offset = 0;
+
+    // write the "RIFF" identifier
+    RIFF.copy(header, offset);
+    offset += RIFF.length;
+
+    // write the file size minus the identifier and this 32-bit int
+    header['writeUInt32' + this.endianness](fileSize - 8, offset);
+    offset += 4;
+
+    // write the "WAVE" identifier
+    WAVE.copy(header, offset);
+    offset += WAVE.length;
+
+    // write the "fmt " sub-chunk identifier
+    fmt.copy(header, offset);
+    offset += fmt.length;
+
+    // write the size of the "fmt " chunk
+    // XXX: value of 16 is hard-coded for raw PCM format. other formats have
+    // different size.
+    header['writeUInt32' + this.endianness](16, offset);
+    offset += 4;
+
+    // write the audio format code
+    header['writeUInt16' + this.endianness](this.format, offset);
+    offset += 2;
+
+    // write the number of channels
+    header['writeUInt16' + this.endianness](this.channels, offset);
+    offset += 2;
+
+    // write the sample rate
+    header['writeUInt32' + this.endianness](this.sampleRate, offset);
+    offset += 4;
+
+    // write the byte rate
+    var byteRate = this.byteRate;
+    if (byteRate == null) {
+      byteRate = this.sampleRate * this.channels * this.bitDepth / 8;
+    }
+    header['writeUInt32' + this.endianness](byteRate, offset);
+    offset += 4;
+
+    // write the block align
+    var blockAlign = this.blockAlign;
+    if (blockAlign == null) {
+      blockAlign = this.channels * this.bitDepth / 8;
+    }
+    header['writeUInt16' + this.endianness](blockAlign, offset);
+    offset += 2;
+
+    // write the bits per sample
+    header['writeUInt16' + this.endianness](this.bitDepth, offset);
+    offset += 2;
+
+    // write the "data" sub-chunk ID
+    data.copy(header, offset);
+    offset += data.length;
+
+    // write the remaining length of the rest of the data
+    header['writeUInt32' + this.endianness](dataLength, offset);
+    offset += 4;
+
+    // save the "header" Buffer for the end, we emit the "header" event at the end
+    // with the "size" values properly filled out. if this stream is being piped to
+    // a file (or anything else seekable), then this correct header should be placed
+    // at the very beginning of the file.
+    this._header = header;
+    this.headerLength = headerLength;
+
+    this.push(header);
   }
-  header['writeUInt32' + this.endianness](byteRate, offset);
-  offset += 4;
 
-  // write the block align
-  var blockAlign = this.blockAlign;
-  if (blockAlign == null) {
-    blockAlign = this.channels * this.bitDepth / 8;
+  /**
+   * Called for the "end" event of this Writer instance.
+   *
+   * @api private
+   */
+  _onEnd(write) {
+    debug('_onEnd()');
   }
-  header['writeUInt16' + this.endianness](blockAlign, offset);
-  offset += 2;
-
-  // write the bits per sample
-  header['writeUInt16' + this.endianness](this.bitDepth, offset);
-  offset += 2;
 
-  // write the "data" sub-chunk ID
-  data.copy(header, offset);
-  offset += data.length;
-
-  // write the remaining length of the rest of the data
-  header['writeUInt32' + this.endianness](dataLength, offset);
-  offset += 4;
-
-  // save the "header" Buffer for the end, we emit the "header" event at the end
-  // with the "size" values properly filled out. if this stream is being piped to
-  // a file (or anything else seekable), then this correct header should be placed
-  // at the very beginning of the file.
-  this._header = header;
-  this.headerLength = headerLength;
-
-  this.push(header);
-};
-
-/**
- * Called for the "end" event of this Writer instance.
- *
- * @api private
- */
-
-Writer.prototype._onEnd = function (write) {
-  debug('_onEnd()');
-};
-
-/**
- * Transform incoming data. We don't do anything special, just pass it through.
- *
- * @api private
- */
-
-Writer.prototype._transform = function (chunk, enc, done) {
-  this.push(chunk);
-  this.bytesProcessed += chunk.length;
-  done();
-};
+  /**
+   * Transform incoming data. We don't do anything special, just pass it through.
+   *
+   * @api private
+   */
+  _transform(chunk, enc, done) {
+    this.push(chunk);
+    this.bytesProcessed += chunk.length;
+    done();
+  }
 
-/**
- * Emits a "header" event after the readable side of the stream has finished.
- *
- * @api private
- */
+  /**
+   * Emits a "header" event after the readable side of the stream has finished.
+   *
+   * @api private
+   */
+  _flush(done) {
+    debug('_flush()');
+    done();
+    this.dataLength = this.bytesProcessed;
+    process.nextTick(this._emitHeader.bind(this));
+  }
 
-Writer.prototype._flush = function (done) {
-  debug('_flush()');
-  done();
-  this.dataLength = this.bytesProcessed;
-  process.nextTick(this._emitHeader.bind(this));
-};
+  /**
+   * Emits the "header" event. This can safely be ignored, or if you are writing
+   * this WAVE file to somewhere that is seekable (i.e. the filesystem), then you
+   * should write this "header" buffer at the beginning of the file to get the
+   * correct file size values in the file. This isn't too important since most audio
+   * players look at the file size rather than those byte values in the header, but
+   * it's good to when when possible.
+   *
+   * @api private
+   */
+  _emitHeader() {
+    debug('_emitHeader()');
+    var dataLength = this.dataLength;
+    var headerLength = this.headerLength;
+    var header = this._header;
+
+    // write the file length at the beginning of the header
+    header['writeUInt32' + this.endianness](dataLength + headerLength - 8, 4);
+
+    // write the data length at the end of the header
+    header['writeUInt32' + this.endianness](dataLength, headerLength - 4);
+
+    this.emit('header', header);
+  }
+}
 
 /**
- * Emits the "header" event. This can safely be ignored, or if you are writing
- * this WAVE file to somewhere that is seekable (i.e. the filesystem), then you
- * should write this "header" buffer at the beginning of the file to get the
- * correct file size values in the file. This isn't too important since most audio
- * players look at the file size rather than those byte values in the header, but
- * it's good to when when possible.
- *
- * @api private
+ * Module exports.
  */
 
-Writer.prototype._emitHeader = function () {
-  debug('_emitHeader()');
-  var dataLength = this.dataLength;
-  var headerLength = this.headerLength;
-  var header = this._header;
-
-  // write the file length at the beginning of the header
-  header['writeUInt32' + this.endianness](dataLength + headerLength - 8, 4);
-
-  // write the data length at the end of the header
-  header['writeUInt32' + this.endianness](dataLength, headerLength - 4);
-
-  this.emit('header', header);
-};
+module.exports = Writer;
\ No newline at end of file
diff --git a/package.json b/package.json
index 9f24691..40ddfaf 100644
--- a/package.json
+++ b/package.json
@@ -6,12 +6,12 @@
   "author": "Nathan Rajlich <nathan@tootallnate.net>",
   "repository": "TooTallNate/node-wav",
   "dependencies": {
-    "buffer-alloc": "^1.1.0",
-    "buffer-from": "^1.0.0",
     "debug": "^2.2.0",
-    "readable-stream": "^1.1.14",
     "stream-parser": "^0.3.1"
   },
+  "engines": {
+    "node": ">=12"
+  },
   "devDependencies": {
     "mocha": "^2.5.3",
     "semistandard": "^12.0.1"
diff --git a/test/reader.js b/test/reader.js
index cc7ff12..7aaee3f 100644
--- a/test/reader.js
+++ b/test/reader.js
@@ -7,7 +7,7 @@
 var fs = require('fs');
 var path = require('path');
 var assert = require('assert');
-var Reader = require('../').Reader;
+var Reader = require('../lib/reader.js');
 
 describe('Reader', function () {
   describe('RIFF - Little-endian', function () {