diff --git a/lib/protocol/errors.js b/lib/protocol/errors.js
index 765e4356..2cdef39d 100644
--- a/lib/protocol/errors.js
+++ b/lib/protocol/errors.js
@@ -14,11 +14,11 @@
 const assert = require('assert');
 
 /**
+ * Verify Error
  * An error thrown during verification. Can be either
  * a mempool transaction validation error or a blockchain
  * block verification error. Ultimately used to send
  * `reject` packets to peers.
- * @constructor
  * @extends Error
  * @param {Block|TX} msg
  * @param {String} code - Reject packet code.
@@ -26,38 +26,43 @@ const assert = require('assert');
  * @param {Number} score - Ban score increase
  * (can be -1 for no reject packet).
  * @param {Boolean} malleated
- * @property {String} code
- * @property {Buffer} hash
- * @property {Number} height (will be the coinbase height if not present).
- * @property {Number} score
- * @property {String} message
- * @property {Boolean} malleated
  */
 
-function VerifyError(msg, code, reason, score, malleated) {
-  Error.call(this);
+class VerifyError extends Error {
+  /**
+   * Create a verify error.
+   * @constructor
+   * @param {Block|TX} msg
+   * @param {String} code - Reject packet code.
+   * @param {String} reason - Reject packet reason.
+   * @param {Number} score - Ban score increase
+   * (can be -1 for no reject packet).
+   * @param {Boolean} malleated
+   */
 
-  assert(typeof code === 'string');
-  assert(typeof reason === 'string');
-  assert(score >= 0);
+  constructor(msg, code, reason, score, malleated) {
+    super();
 
-  this.type = 'VerifyError';
-  this.message = '';
-  this.code = code;
-  this.reason = reason;
-  this.score = score;
-  this.hash = msg.hash('hex');
-  this.malleated = malleated || false;
+    assert(typeof code === 'string');
+    assert(typeof reason === 'string');
+    assert(score >= 0);
 
-  this.message = `Verification failure: ${reason}`
-    + ` (code=${code} score=${score} hash=${msg.rhash()})`;
+    this.type = 'VerifyError';
+    this.message = '';
+    this.code = code;
+    this.reason = reason;
+    this.score = score;
+    this.hash = msg.hash('hex');
+    this.malleated = malleated || false;
 
-  if (Error.captureStackTrace)
-    Error.captureStackTrace(this, VerifyError);
+    this.message = `Verification failure: ${reason}`
+      + ` (code=${code} score=${score} hash=${msg.rhash()})`;
+
+    if (Error.captureStackTrace)
+      Error.captureStackTrace(this, VerifyError);
+  }
 }
 
-Object.setPrototypeOf(VerifyError.prototype, Error.prototype);
-
 /*
  * Expose
  */
diff --git a/lib/protocol/network.js b/lib/protocol/network.js
index 412bc303..057e2fe8 100644
--- a/lib/protocol/network.js
+++ b/lib/protocol/network.js
@@ -14,49 +14,341 @@ const consensus = require('./consensus');
 const TimeData = require('./timedata');
 
 /**
+ * Network
  * Represents a network.
  * @alias module:protocol.Network
- * @constructor
- * @param {Object|NetworkType} options - See {@link module:network}.
  */
 
-function Network(options) {
-  if (!(this instanceof Network))
-    return new Network(options);
+class Network {
+  /**
+   * Create a network.
+   * @constructor
+   * @param {Object} options
+   */
 
-  assert(!Network[options.type], 'Cannot create two networks.');
+  constructor(options) {
+    assert(!Network[options.type], 'Cannot create two networks.');
 
-  this.type = options.type;
-  this.seeds = options.seeds;
-  this.magic = options.magic;
-  this.port = options.port;
-  this.checkpointMap = options.checkpointMap;
-  this.lastCheckpoint = options.lastCheckpoint;
-  this.checkpoints = [];
-  this.halvingInterval = options.halvingInterval;
-  this.genesis = options.genesis;
-  this.genesisBlock = options.genesisBlock;
-  this.pow = options.pow;
-  this.block = options.block;
-  this.bip30 = options.bip30;
-  this.activationThreshold = options.activationThreshold;
-  this.minerWindow = options.minerWindow;
-  this.deployments = options.deployments;
-  this.deploys = options.deploys;
-  this.unknownBits = ~consensus.VERSION_TOP_MASK;
-  this.keyPrefix = options.keyPrefix;
-  this.addressPrefix = options.addressPrefix;
-  this.requireStandard = options.requireStandard;
-  this.rpcPort = options.rpcPort;
-  this.walletPort = options.walletPort;
-  this.minRelay = options.minRelay;
-  this.feeRate = options.feeRate;
-  this.maxFeeRate = options.maxFeeRate;
-  this.selfConnect = options.selfConnect;
-  this.requestMempool = options.requestMempool;
-  this.time = new TimeData();
+    this.type = options.type;
+    this.seeds = options.seeds;
+    this.magic = options.magic;
+    this.port = options.port;
+    this.checkpointMap = options.checkpointMap;
+    this.lastCheckpoint = options.lastCheckpoint;
+    this.checkpoints = [];
+    this.halvingInterval = options.halvingInterval;
+    this.genesis = options.genesis;
+    this.genesisBlock = options.genesisBlock;
+    this.pow = options.pow;
+    this.block = options.block;
+    this.bip30 = options.bip30;
+    this.activationThreshold = options.activationThreshold;
+    this.minerWindow = options.minerWindow;
+    this.deployments = options.deployments;
+    this.deploys = options.deploys;
+    this.unknownBits = ~consensus.VERSION_TOP_MASK;
+    this.keyPrefix = options.keyPrefix;
+    this.addressPrefix = options.addressPrefix;
+    this.requireStandard = options.requireStandard;
+    this.rpcPort = options.rpcPort;
+    this.walletPort = options.walletPort;
+    this.minRelay = options.minRelay;
+    this.feeRate = options.feeRate;
+    this.maxFeeRate = options.maxFeeRate;
+    this.selfConnect = options.selfConnect;
+    this.requestMempool = options.requestMempool;
+    this.time = new TimeData();
 
-  this.init();
+    this.init();
+  }
+
+  /**
+   * Get a deployment by bit index.
+   * @param {Number} bit
+   * @returns {Object}
+   */
+
+  init() {
+    let bits = 0;
+
+    for (const deployment of this.deploys)
+      bits |= 1 << deployment.bit;
+
+    bits |= consensus.VERSION_TOP_MASK;
+
+    this.unknownBits = ~bits >>> 0;
+
+    for (const key of Object.keys(this.checkpointMap)) {
+      const hash = this.checkpointMap[key];
+      const height = Number(key);
+
+      this.checkpoints.push({ hash, height });
+    }
+
+    this.checkpoints.sort(cmpNode);
+  }
+
+  /**
+   * Get a deployment by bit index.
+   * @param {Number} bit
+   * @returns {Object}
+   */
+
+  byBit(bit) {
+    const index = binary.search(this.deploys, bit, cmpBit);
+
+    if (index === -1)
+      return null;
+
+    return this.deploys[index];
+  }
+
+  /**
+   * Get network adjusted time.
+   * @returns {Number}
+   */
+
+  now() {
+    return this.time.now();
+  }
+
+  /**
+   * Get network adjusted time in milliseconds.
+   * @returns {Number}
+   */
+
+  ms() {
+    return this.time.ms();
+  }
+
+  /**
+   * Create a network. Get existing network if possible.
+   * @param {NetworkType|Object} options
+   * @returns {Network}
+   */
+
+  static create(options) {
+    if (typeof options === 'string')
+      options = networks[options];
+
+    assert(options, 'Unknown network.');
+
+    if (Network[options.type])
+      return Network[options.type];
+
+    const network = new Network(options);
+
+    Network[network.type] = network;
+
+    if (!Network.primary)
+      Network.primary = network;
+
+    return network;
+  }
+
+  /**
+   * Set the default network. This network will be used
+   * if nothing is passed as the `network` option for
+   * certain objects.
+   * @param {NetworkType} type - Network type.
+   * @returns {Network}
+   */
+
+  static set(type) {
+    assert(typeof type === 'string', 'Bad network.');
+    Network.primary = Network.get(type);
+    Network.type = type;
+    return Network.primary;
+  }
+
+  /**
+   * Get a network with a string or a Network object.
+   * @param {NetworkType|Network} type - Network type.
+   * @returns {Network}
+   */
+
+  static get(type) {
+    if (!type) {
+      assert(Network.primary, 'No default network.');
+      return Network.primary;
+    }
+
+    if (type instanceof Network)
+      return type;
+
+    if (typeof type === 'string')
+      return Network.create(type);
+
+    throw new Error('Unknown network.');
+  }
+
+  /**
+   * Get a network with a string or a Network object.
+   * @param {NetworkType|Network} type - Network type.
+   * @returns {Network}
+   */
+
+  static ensure(type) {
+    if (!type) {
+      assert(Network.primary, 'No default network.');
+      return Network.primary;
+    }
+
+    if (type instanceof Network)
+      return type;
+
+    if (typeof type === 'string') {
+      if (networks[type])
+        return Network.create(type);
+    }
+
+    assert(Network.primary, 'No default network.');
+
+    return Network.primary;
+  }
+
+  /**
+   * Get a network by an associated comparator.
+   * @private
+   * @param {Object} value
+   * @param {Function} compare
+   * @param {Network|null} network
+   * @param {String} name
+   * @returns {Network}
+   */
+
+  static by(value, compare, network, name) {
+    if (network) {
+      network = Network.get(network);
+      if (compare(network, value))
+        return network;
+      throw new Error(`Network mismatch for ${name}.`);
+    }
+
+    for (const type of networks.types) {
+      network = networks[type];
+      if (compare(network, value))
+        return Network.get(type);
+    }
+
+    throw new Error(`Network not found for ${name}.`);
+  }
+
+  /**
+   * Get a network by its magic number.
+   * @param {Number} value
+   * @param {Network?} network
+   * @returns {Network}
+   */
+
+  static fromMagic(value, network) {
+    return Network.by(value, cmpMagic, network, 'magic number');
+  }
+
+  /**
+   * Get a network by its WIF prefix.
+   * @param {Number} value
+   * @param {Network?} network
+   * @returns {Network}
+   */
+
+  static fromWIF(prefix, network) {
+    return Network.by(prefix, cmpWIF, network, 'WIF');
+  }
+
+  /**
+   * Get a network by its xpubkey prefix.
+   * @param {Number} value
+   * @param {Network?} network
+   * @returns {Network}
+   */
+
+  static fromPublic(prefix, network) {
+    return Network.by(prefix, cmpPub, network, 'xpubkey');
+  }
+
+  /**
+   * Get a network by its xprivkey prefix.
+   * @param {Number} value
+   * @param {Network?} network
+   * @returns {Network}
+   */
+
+  static fromPrivate(prefix, network) {
+    return Network.by(prefix, cmpPriv, network, 'xprivkey');
+  }
+
+  /**
+   * Get a network by its xpubkey base58 prefix.
+   * @param {String} prefix
+   * @param {Network?} network
+   * @returns {Network}
+   */
+
+  static fromPublic58(prefix, network) {
+    return Network.by(prefix, cmpPub58, network, 'xpubkey');
+  }
+
+  /**
+   * Get a network by its xprivkey base58 prefix.
+   * @param {String} prefix
+   * @param {Network?} network
+   * @returns {Network}
+   */
+
+  static fromPrivate58(prefix, network) {
+    return Network.by(prefix, cmpPriv58, network, 'xprivkey');
+  }
+
+  /**
+   * Get a network by its base58 address prefix.
+   * @param {Number} value
+   * @param {Network?} network
+   * @returns {Network}
+   */
+
+  static fromAddress(prefix, network) {
+    return Network.by(prefix, cmpAddress, network, 'base58 address');
+  }
+
+  /**
+   * Get a network by its bech32 address prefix.
+   * @param {String} hrp
+   * @param {Network?} network
+   * @returns {Network}
+   */
+
+  static fromBech32(hrp, network) {
+    return Network.by(hrp, cmpBech32, network, 'bech32 address');
+  }
+
+  /**
+   * Convert the network to a string.
+   * @returns {String}
+   */
+
+  toString() {
+    return this.type;
+  }
+
+  /**
+   * Inspect the network.
+   * @returns {String}
+   */
+
+  inspect() {
+    return `<Network: ${this.type}>`;
+  }
+
+  /**
+   * Test an object to see if it is a Network.
+   * @param {Object} obj
+   * @returns {Boolean}
+   */
+
+  static isNetwork(obj) {
+    return obj instanceof Network;
+  }
 }
 
 /**
@@ -83,294 +375,6 @@ Network.regtest = null;
 Network.segnet4 = null;
 Network.simnet = null;
 
-/**
- * Get a deployment by bit index.
- * @param {Number} bit
- * @returns {Object}
- */
-
-Network.prototype.init = function init() {
-  let bits = 0;
-
-  for (const deployment of this.deploys)
-    bits |= 1 << deployment.bit;
-
-  bits |= consensus.VERSION_TOP_MASK;
-
-  this.unknownBits = ~bits >>> 0;
-
-  for (const key of Object.keys(this.checkpointMap)) {
-    const hash = this.checkpointMap[key];
-    const height = Number(key);
-
-    this.checkpoints.push({ hash, height });
-  }
-
-  this.checkpoints.sort(cmpNode);
-};
-
-/**
- * Get a deployment by bit index.
- * @param {Number} bit
- * @returns {Object}
- */
-
-Network.prototype.byBit = function byBit(bit) {
-  const index = binary.search(this.deploys, bit, cmpBit);
-
-  if (index === -1)
-    return null;
-
-  return this.deploys[index];
-};
-
-/**
- * Get network adjusted time.
- * @returns {Number}
- */
-
-Network.prototype.now = function now() {
-  return this.time.now();
-};
-
-/**
- * Get network adjusted time in milliseconds.
- * @returns {Number}
- */
-
-Network.prototype.ms = function ms() {
-  return this.time.ms();
-};
-
-/**
- * Create a network. Get existing network if possible.
- * @param {NetworkType|Object} options
- * @returns {Network}
- */
-
-Network.create = function create(options) {
-  if (typeof options === 'string')
-    options = networks[options];
-
-  assert(options, 'Unknown network.');
-
-  if (Network[options.type])
-    return Network[options.type];
-
-  const network = new Network(options);
-
-  Network[network.type] = network;
-
-  if (!Network.primary)
-    Network.primary = network;
-
-  return network;
-};
-
-/**
- * Set the default network. This network will be used
- * if nothing is passed as the `network` option for
- * certain objects.
- * @param {NetworkType} type - Network type.
- * @returns {Network}
- */
-
-Network.set = function set(type) {
-  assert(typeof type === 'string', 'Bad network.');
-  Network.primary = Network.get(type);
-  Network.type = type;
-  return Network.primary;
-};
-
-/**
- * Get a network with a string or a Network object.
- * @param {NetworkType|Network} type - Network type.
- * @returns {Network}
- */
-
-Network.get = function get(type) {
-  if (!type) {
-    assert(Network.primary, 'No default network.');
-    return Network.primary;
-  }
-
-  if (type instanceof Network)
-    return type;
-
-  if (typeof type === 'string')
-    return Network.create(type);
-
-  throw new Error('Unknown network.');
-};
-
-/**
- * Get a network with a string or a Network object.
- * @param {NetworkType|Network} type - Network type.
- * @returns {Network}
- */
-
-Network.ensure = function ensure(type) {
-  if (!type) {
-    assert(Network.primary, 'No default network.');
-    return Network.primary;
-  }
-
-  if (type instanceof Network)
-    return type;
-
-  if (typeof type === 'string') {
-    if (networks[type])
-      return Network.create(type);
-  }
-
-  assert(Network.primary, 'No default network.');
-
-  return Network.primary;
-};
-
-/**
- * Get a network by an associated comparator.
- * @private
- * @param {Object} value
- * @param {Function} compare
- * @param {Network|null} network
- * @param {String} name
- * @returns {Network}
- */
-
-Network.by = function by(value, compare, network, name) {
-  if (network) {
-    network = Network.get(network);
-    if (compare(network, value))
-      return network;
-    throw new Error(`Network mismatch for ${name}.`);
-  }
-
-  for (const type of networks.types) {
-    network = networks[type];
-    if (compare(network, value))
-      return Network.get(type);
-  }
-
-  throw new Error(`Network not found for ${name}.`);
-};
-
-/**
- * Get a network by its magic number.
- * @param {Number} value
- * @param {Network?} network
- * @returns {Network}
- */
-
-Network.fromMagic = function fromMagic(value, network) {
-  return Network.by(value, cmpMagic, network, 'magic number');
-};
-
-/**
- * Get a network by its WIF prefix.
- * @param {Number} value
- * @param {Network?} network
- * @returns {Network}
- */
-
-Network.fromWIF = function fromWIF(prefix, network) {
-  return Network.by(prefix, cmpWIF, network, 'WIF');
-};
-
-/**
- * Get a network by its xpubkey prefix.
- * @param {Number} value
- * @param {Network?} network
- * @returns {Network}
- */
-
-Network.fromPublic = function fromPublic(prefix, network) {
-  return Network.by(prefix, cmpPub, network, 'xpubkey');
-};
-
-/**
- * Get a network by its xprivkey prefix.
- * @param {Number} value
- * @param {Network?} network
- * @returns {Network}
- */
-
-Network.fromPrivate = function fromPrivate(prefix, network) {
-  return Network.by(prefix, cmpPriv, network, 'xprivkey');
-};
-
-/**
- * Get a network by its xpubkey base58 prefix.
- * @param {String} prefix
- * @param {Network?} network
- * @returns {Network}
- */
-
-Network.fromPublic58 = function fromPublic58(prefix, network) {
-  return Network.by(prefix, cmpPub58, network, 'xpubkey');
-};
-
-/**
- * Get a network by its xprivkey base58 prefix.
- * @param {String} prefix
- * @param {Network?} network
- * @returns {Network}
- */
-
-Network.fromPrivate58 = function fromPrivate58(prefix, network) {
-  return Network.by(prefix, cmpPriv58, network, 'xprivkey');
-};
-
-/**
- * Get a network by its base58 address prefix.
- * @param {Number} value
- * @param {Network?} network
- * @returns {Network}
- */
-
-Network.fromAddress = function fromAddress(prefix, network) {
-  return Network.by(prefix, cmpAddress, network, 'base58 address');
-};
-
-/**
- * Get a network by its bech32 address prefix.
- * @param {String} hrp
- * @param {Network?} network
- * @returns {Network}
- */
-
-Network.fromBech32 = function fromBech32(hrp, network) {
-  return Network.by(hrp, cmpBech32, network, 'bech32 address');
-};
-
-/**
- * Convert the network to a string.
- * @returns {String}
- */
-
-Network.prototype.toString = function toString() {
-  return this.type;
-};
-
-/**
- * Inspect the network.
- * @returns {String}
- */
-
-Network.prototype.inspect = function inspect() {
-  return `<Network: ${this.type}>`;
-};
-
-/**
- * Test an object to see if it is a Network.
- * @param {Object} obj
- * @returns {Boolean}
- */
-
-Network.isNetwork = function isNetwork(obj) {
-  return obj instanceof Network;
-};
-
 /*
  * Set initial network.
  */
diff --git a/lib/protocol/timedata.js b/lib/protocol/timedata.js
index e3572408..cfff6fcb 100644
--- a/lib/protocol/timedata.js
+++ b/lib/protocol/timedata.js
@@ -12,123 +12,126 @@ const util = require('../utils/util');
 const binary = require('../utils/binary');
 
 /**
+ * Time Data
  * An object which handles "adjusted time". This may not
  * look it, but this is actually a semi-consensus-critical
  * piece of code. It handles version packets from peers
  * and calculates what to offset our system clock's time by.
  * @alias module:protocol.TimeData
- * @constructor
- * @param {Number} [limit=200]
+ * @extends EventEmitter
  * @property {Array} samples
  * @property {Object} known
  * @property {Number} limit
  * @property {Number} offset
  */
 
-function TimeData(limit) {
-  if (!(this instanceof TimeData))
-    return new TimeData(limit);
+class TimeData extends EventEmitter {
+  /**
+   * Create time data.
+   * @constructor
+   * @param {Number} [limit=200]
+   */
 
-  EventEmitter.call(this);
+  constructor(limit) {
+    super();
 
-  if (limit == null)
-    limit = 200;
+    if (limit == null)
+      limit = 200;
 
-  this.samples = [];
-  this.known = new Map();
-  this.limit = limit;
-  this.offset = 0;
-  this.checked = false;
-}
+    this.samples = [];
+    this.known = new Map();
+    this.limit = limit;
+    this.offset = 0;
+    this.checked = false;
+  }
 
-Object.setPrototypeOf(TimeData.prototype, EventEmitter.prototype);
+  /**
+   * Add time data.
+   * @param {String} id
+   * @param {Number} time
+   */
 
-/**
- * Add time data.
- * @param {String} id
- * @param {Number} time
- */
+  add(id, time) {
+    if (this.samples.length >= this.limit)
+      return;
 
-TimeData.prototype.add = function add(id, time) {
-  if (this.samples.length >= this.limit)
-    return;
+    if (this.known.has(id))
+      return;
 
-  if (this.known.has(id))
-    return;
+    const sample = time - util.now();
 
-  const sample = time - util.now();
+    this.known.set(id, sample);
 
-  this.known.set(id, sample);
+    binary.insert(this.samples, sample, compare);
 
-  binary.insert(this.samples, sample, compare);
+    this.emit('sample', sample, this.samples.length);
 
-  this.emit('sample', sample, this.samples.length);
+    if (this.samples.length >= 5 && this.samples.length % 2 === 1) {
+      let median = this.samples[this.samples.length >>> 1];
 
-  if (this.samples.length >= 5 && this.samples.length % 2 === 1) {
-    let median = this.samples[this.samples.length >>> 1];
+      if (Math.abs(median) >= 70 * 60) {
+        if (!this.checked) {
+          let match = false;
 
-    if (Math.abs(median) >= 70 * 60) {
-      if (!this.checked) {
-        let match = false;
+          for (const offset of this.samples) {
+            if (offset !== 0 && Math.abs(offset) < 5 * 60) {
+              match = true;
+              break;
+            }
+          }
 
-        for (const offset of this.samples) {
-          if (offset !== 0 && Math.abs(offset) < 5 * 60) {
-            match = true;
-            break;
+          if (!match) {
+            this.checked = true;
+            this.emit('mismatch');
           }
         }
 
-        if (!match) {
-          this.checked = true;
-          this.emit('mismatch');
-        }
+        median = 0;
       }
 
-      median = 0;
+      this.offset = median;
+      this.emit('offset', this.offset);
     }
-
-    this.offset = median;
-    this.emit('offset', this.offset);
   }
-};
 
-/**
- * Get the current adjusted time.
- * @returns {Number} Adjusted Time.
- */
+  /**
+   * Get the current adjusted time.
+   * @returns {Number} Adjusted Time.
+   */
 
-TimeData.prototype.now = function now() {
-  return util.now() + this.offset;
-};
+  now() {
+    return util.now() + this.offset;
+  }
 
-/**
- * Adjust a timestamp.
- * @param {Number} time
- * @returns {Number} Adjusted Time.
- */
+  /**
+   * Adjust a timestamp.
+   * @param {Number} time
+   * @returns {Number} Adjusted Time.
+   */
 
-TimeData.prototype.adjust = function adjust(time) {
-  return time + this.offset;
-};
+  adjust(time) {
+    return time + this.offset;
+  }
 
-/**
- * Unadjust a timestamp.
- * @param {Number} time
- * @returns {Number} Local Time.
- */
+  /**
+   * Unadjust a timestamp.
+   * @param {Number} time
+   * @returns {Number} Local Time.
+   */
 
-TimeData.prototype.local = function local(time) {
-  return time - this.offset;
-};
+  local(time) {
+    return time - this.offset;
+  }
 
-/**
- * Get the current adjusted time in milliseconds.
- * @returns {Number} Adjusted Time.
- */
+  /**
+   * Get the current adjusted time in milliseconds.
+   * @returns {Number} Adjusted Time.
+   */
 
-TimeData.prototype.ms = function ms() {
-  return Date.now() + this.offset * 1000;
-};
+  ms() {
+    return Date.now() + this.offset * 1000;
+  }
+}
 
 /*
  * Helpers