diff --git a/lib/bcoin.js b/lib/bcoin.js
index 7a3c0158..c5c58f86 100644
--- a/lib/bcoin.js
+++ b/lib/bcoin.js
@@ -6,10 +6,6 @@
 
 var bcoin = exports;
 var assert = require('assert');
-var inherits = require('inherits');
-var elliptic = require('elliptic');
-var bn = require('bn.js');
-var hash = require('hash.js');
 
 bcoin.isBrowser =
   (typeof process !== 'undefined' && process.browser)
@@ -21,7 +17,8 @@ if (process.env.BCOIN_DEBUG) {
     bcoin.debug = +bcoin.debug === 1;
 }
 
-bcoin.dir = process.env.HOME + '/.bcoin';
+bcoin.bn = require('bn.js');
+bcoin.elliptic = require('elliptic');
 
 if (!bcoin.isBrowser) {
   bcoin.fs = require('f' + 's');
@@ -34,8 +31,12 @@ if (!bcoin.isBrowser) {
     utils.debug('Warning secp256k1 not found.'
       + ' Full block validation will be slow.');
   }
+} else {
+  bcoin.hash = require('hash.js');
 }
 
+bcoin.dir = process.env.HOME + '/.bcoin';
+
 if (bcoin.fs) {
   try {
     bcoin.fs.statSync(bcoin.dir, 0o750);
@@ -44,17 +45,10 @@ if (bcoin.fs) {
   }
 }
 
-bcoin.inherits = inherits;
-bcoin.elliptic = elliptic;
-bcoin.bn = bn;
-bcoin.hash = hash;
-
-bcoin.ecdsa = elliptic.ec('secp256k1');
-
+bcoin.ecdsa = bcoin.elliptic.ec('secp256k1');
 assert(!bcoin.ecdsa.signature);
-assert(!bcoin.ecdsa.keypair);
-
 bcoin.ecdsa.signature = require('elliptic/lib/elliptic/ec/signature');
+assert(!bcoin.ecdsa.keypair);
 bcoin.ecdsa.keypair = require('elliptic/lib/elliptic/ec/key');
 
 bcoin.utils = require('./bcoin/utils');
diff --git a/lib/bcoin/address.js b/lib/bcoin/address.js
index 06652802..d56781ba 100644
--- a/lib/bcoin/address.js
+++ b/lib/bcoin/address.js
@@ -5,9 +5,7 @@
  */
 
 var bcoin = require('../bcoin');
-var hash = require('hash.js');
 var bn = require('bn.js');
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 var utils = bcoin.utils;
 var assert = utils.assert;
@@ -68,7 +66,7 @@ function Address(options) {
     this.setRedeem(options.redeem || options.script);
 }
 
-inherits(Address, EventEmitter);
+utils.inherits(Address, EventEmitter);
 
 Address.prototype.__defineGetter__('balance', function() {
   return this.getBalance();
diff --git a/lib/bcoin/blockdb.js b/lib/bcoin/blockdb.js
index ee22765d..aaf9cda2 100644
--- a/lib/bcoin/blockdb.js
+++ b/lib/bcoin/blockdb.js
@@ -7,8 +7,6 @@
 var bcoin = require('../bcoin');
 var utils = bcoin.utils;
 var assert = utils.assert;
-var levelup = require('levelup');
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 var network = bcoin.protocol.network;
 var fs = bcoin.fs;
@@ -19,10 +17,14 @@ var fs = bcoin.fs;
 
 function BlockDB(options) {
   var self = this;
+  var levelup;
 
   if (!(this instanceof BlockDB))
     return new BlockDB(options);
 
+  // Some lazy loading
+  levelup = require('levelup');
+
   EventEmitter.call(this);
 
   if (!options)
@@ -64,7 +66,7 @@ function BlockDB(options) {
   });
 }
 
-inherits(BlockDB, EventEmitter);
+utils.inherits(BlockDB, EventEmitter);
 
 BlockDB.prototype.close = function close(callback) {
   var self = this;
diff --git a/lib/bcoin/chain.js b/lib/bcoin/chain.js
index c29c53ea..d8b7d9b8 100644
--- a/lib/bcoin/chain.js
+++ b/lib/bcoin/chain.js
@@ -4,9 +4,7 @@
  * https://github.com/indutny/bcoin
  */
 
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
-var request = require('request');
 
 var bcoin = require('../bcoin');
 var bn = require('bn.js');
@@ -62,7 +60,7 @@ function Chain(options) {
   this._init();
 }
 
-inherits(Chain, EventEmitter);
+utils.inherits(Chain, EventEmitter);
 
 Chain.prototype._init = function _init() {
   var self = this;
@@ -283,6 +281,7 @@ Chain.prototype._preload = function _preload(callback) {
   var self = this;
   var url = 'https://headers.electrum.org/blockchain_headers';
   var chainHeight, buf, height, stream;
+  var request;
 
   if (!this.options.preload)
     return callback();
@@ -290,6 +289,12 @@ Chain.prototype._preload = function _preload(callback) {
   if (network.type !== 'main')
     return callback(new Error('Electrum.org only offers `main` headers.'));
 
+  try {
+    request = require('request');
+  } catch (e) {
+    return callback(e);
+  }
+
   utils.debug('Loading %s', url);
 
   stream = request.get(url);
diff --git a/lib/bcoin/chainblock.js b/lib/bcoin/chainblock.js
index 8595ec87..3d2d11e5 100644
--- a/lib/bcoin/chainblock.js
+++ b/lib/bcoin/chainblock.js
@@ -4,7 +4,6 @@
  * https://github.com/indutny/bcoin
  */
 
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 
 var bcoin = require('../bcoin');
diff --git a/lib/bcoin/chaindb.js b/lib/bcoin/chaindb.js
index 32b7b3f2..cf2e85b2 100644
--- a/lib/bcoin/chaindb.js
+++ b/lib/bcoin/chaindb.js
@@ -4,7 +4,6 @@
  * https://github.com/indutny/bcoin
  */
 
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 
 var bcoin = require('../bcoin');
@@ -59,7 +58,7 @@ function ChainDB(chain, options) {
   this._init();
 }
 
-inherits(ChainDB, EventEmitter);
+utils.inherits(ChainDB, EventEmitter);
 
 ChainDB.prototype._init = function _init() {
   var genesis = bcoin.chainblock.fromJSON(this.chain, {
diff --git a/lib/bcoin/coin.js b/lib/bcoin/coin.js
index 1daddd0e..8cf51726 100644
--- a/lib/bcoin/coin.js
+++ b/lib/bcoin/coin.js
@@ -6,7 +6,6 @@
 
 var bn = require('bn.js');
 var bcoin = require('../bcoin');
-var inherits = require('inherits');
 var utils = bcoin.utils;
 var assert = utils.assert;
 var constants = bcoin.protocol.constants;
@@ -68,7 +67,7 @@ function Coin(tx, index) {
   assert(typeof this.spent === 'boolean');
 }
 
-inherits(Coin, bcoin.output);
+utils.inherits(Coin, bcoin.output);
 
 Coin.prototype.__defineGetter__('chain', function() {
   return this._chain || bcoin.chain.global;
diff --git a/lib/bcoin/ec.js b/lib/bcoin/ec.js
index 605196a6..3f80646f 100644
--- a/lib/bcoin/ec.js
+++ b/lib/bcoin/ec.js
@@ -45,14 +45,14 @@ ec.verify = function verify(msg, sig, key, historical) {
   // Note: We only do this for historical data!
   // https://github.com/indutny/elliptic/issues/78
   if (historical)
-    sig = bcoin.ec.normalizeLength(sig);
+    sig = ec.normalizeLength(sig);
 
   try {
     if (bcoin.secp256k1) {
       // secp256k1 fails on low s values. This is
       // bad for verifying historical data.
       if (historical)
-        sig = bcoin.ec.toLowS(sig);
+        sig = ec.toLowS(sig);
 
       msg = new Buffer(msg);
       sig = new Buffer(sig);
diff --git a/lib/bcoin/hd.js b/lib/bcoin/hd.js
index 3ab3d096..638bac36 100644
--- a/lib/bcoin/hd.js
+++ b/lib/bcoin/hd.js
@@ -51,9 +51,7 @@
  */
 
 var bcoin = require('../bcoin');
-var hash = require('hash.js');
 var bn = require('bn.js');
-var inherits = require('inherits');
 var elliptic = require('elliptic');
 var utils = bcoin.utils;
 var assert = utils.assert;
@@ -185,7 +183,7 @@ function HDPrivateKey(options) {
   this.isPublic = false;
 }
 
-inherits(HDPrivateKey, HD);
+utils.inherits(HDPrivateKey, HD);
 
 HDPrivateKey.prototype.scan44 = function scan44(options, txByAddress, callback) {
   var self = this;
@@ -952,7 +950,7 @@ function HDPublicKey(options) {
   this.isPublic = true;
 }
 
-inherits(HDPublicKey, HD);
+utils.inherits(HDPublicKey, HD);
 
 HDPublicKey.prototype.scan44 = HDPrivateKey.prototype.scan44;
 HDPublicKey.prototype.deriveAccount44 = HDPrivateKey.prototype.deriveAccount44;
diff --git a/lib/bcoin/mempool.js b/lib/bcoin/mempool.js
index c873128f..5a98b35a 100644
--- a/lib/bcoin/mempool.js
+++ b/lib/bcoin/mempool.js
@@ -4,7 +4,6 @@
  * https://github.com/indutny/bcoin
  */
 
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 
 var bcoin = require('../bcoin');
@@ -42,7 +41,7 @@ function Mempool(node, options) {
   this._init();
 }
 
-inherits(Mempool, EventEmitter);
+utils.inherits(Mempool, EventEmitter);
 
 Mempool.prototype._init = function _init() {
   ;
diff --git a/lib/bcoin/miner.js b/lib/bcoin/miner.js
index 905fb1a3..c66807b5 100644
--- a/lib/bcoin/miner.js
+++ b/lib/bcoin/miner.js
@@ -10,7 +10,6 @@ var assert = utils.assert;
 var constants = bcoin.protocol.constants;
 
 var bn = require('bn.js');
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 
 /**
@@ -48,7 +47,7 @@ function Miner(pool, options) {
   this._init();
 }
 
-inherits(Miner, EventEmitter);
+utils.inherits(Miner, EventEmitter);
 
 Miner.prototype._init = function _init() {
   var self = this;
diff --git a/lib/bcoin/node.js b/lib/bcoin/node.js
index 1c1ea831..427fc1c0 100644
--- a/lib/bcoin/node.js
+++ b/lib/bcoin/node.js
@@ -4,7 +4,6 @@
  * https://github.com/indutny/bcoin
  */
 
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 var bcoin = require('../bcoin');
 var bn = require('bn.js');
@@ -49,7 +48,7 @@ function Node(options) {
   this._init();
 }
 
-inherits(Node, EventEmitter);
+utils.inherits(Node, EventEmitter);
 
 Node.prototype._init = function _init() {
   var self = this;
diff --git a/lib/bcoin/output.js b/lib/bcoin/output.js
index f8cb2fae..218ba644 100644
--- a/lib/bcoin/output.js
+++ b/lib/bcoin/output.js
@@ -6,7 +6,6 @@
 
 var bn = require('bn.js');
 var bcoin = require('../bcoin');
-var inherits = require('inherits');
 var utils = bcoin.utils;
 var assert = utils.assert;
 var constants = bcoin.protocol.constants;
diff --git a/lib/bcoin/peer.js b/lib/bcoin/peer.js
index c7f8ce69..bcb557de 100644
--- a/lib/bcoin/peer.js
+++ b/lib/bcoin/peer.js
@@ -4,7 +4,6 @@
  * https://github.com/indutny/bcoin
  */
 
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 
 var bcoin = require('../bcoin');
@@ -97,7 +96,7 @@ function Peer(pool, options) {
   this._init();
 }
 
-inherits(Peer, EventEmitter);
+utils.inherits(Peer, EventEmitter);
 
 Peer.uid = new bn(0);
 
diff --git a/lib/bcoin/pool.js b/lib/bcoin/pool.js
index c8543c57..304dbbb3 100644
--- a/lib/bcoin/pool.js
+++ b/lib/bcoin/pool.js
@@ -4,7 +4,6 @@
  * https://github.com/indutny/bcoin
  */
 
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 
 var bcoin = require('../bcoin');
@@ -162,7 +161,7 @@ function Pool(options) {
   });
 }
 
-inherits(Pool, EventEmitter);
+utils.inherits(Pool, EventEmitter);
 
 Pool.prototype._init = function _init() {
   var self = this;
diff --git a/lib/bcoin/protocol/parser.js b/lib/bcoin/protocol/parser.js
index 3ea0b292..96687572 100644
--- a/lib/bcoin/protocol/parser.js
+++ b/lib/bcoin/protocol/parser.js
@@ -4,7 +4,6 @@
  * https://github.com/indutny/bcoin
  */
 
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 var bn = require('bn.js');
 
@@ -30,7 +29,7 @@ function Parser() {
   this.packet = null;
 }
 
-inherits(Parser, EventEmitter);
+utils.inherits(Parser, EventEmitter);
 
 Parser.prototype._error = function _error(str) {
   this.emit('error', new Error(str));
diff --git a/lib/bcoin/spvnode.js b/lib/bcoin/spvnode.js
index 98c89170..68b87ab1 100644
--- a/lib/bcoin/spvnode.js
+++ b/lib/bcoin/spvnode.js
@@ -4,7 +4,6 @@
  * https://github.com/indutny/bcoin
  */
 
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 var bcoin = require('../bcoin');
 var bn = require('bn.js');
@@ -46,7 +45,7 @@ function SPVNode(options) {
   this._init();
 }
 
-inherits(SPVNode, EventEmitter);
+utils.inherits(SPVNode, EventEmitter);
 
 SPVNode.prototype._init = function _init() {
   var self = this;
diff --git a/lib/bcoin/tx-pool.js b/lib/bcoin/tx-pool.js
index c16731dd..d9520257 100644
--- a/lib/bcoin/tx-pool.js
+++ b/lib/bcoin/tx-pool.js
@@ -5,7 +5,6 @@
  */
 
 var bn = require('bn.js');
-var inherits = require('inherits');
 var bcoin = require('../bcoin');
 var utils = bcoin.utils;
 var assert = bcoin.utils.assert;
@@ -38,7 +37,7 @@ function TXPool(wallet, txs) {
   this._init(txs);
 }
 
-inherits(TXPool, EventEmitter);
+utils.inherits(TXPool, EventEmitter);
 
 TXPool.prototype._init = function _init(txs) {
   var self = this;
diff --git a/lib/bcoin/utils.js b/lib/bcoin/utils.js
index 4cc7ccb4..e507e1cb 100644
--- a/lib/bcoin/utils.js
+++ b/lib/bcoin/utils.js
@@ -8,7 +8,6 @@ var utils = exports;
 
 var bcoin = require('../bcoin');
 var bn = require('bn.js');
-var hash = require('hash.js');
 var util = require('util');
 
 /**
@@ -153,7 +152,7 @@ utils.ripemd160 = function ripemd160(data, enc) {
   var result;
 
   if (!bcoin.crypto)
-    return hash.ripemd160().update(data, enc).digest();
+    return bcoin.hash.ripemd160().update(data, enc).digest();
 
   if (Array.isArray(data))
     data = new Buffer(data);
@@ -167,7 +166,7 @@ utils.sha1 = function sha1(data, enc) {
   var result;
 
   if (!bcoin.crypto)
-    return hash.sha1().update(data, enc).digest();
+    return bcoin.hash.sha1().update(data, enc).digest();
 
   if (Array.isArray(data))
     data = new Buffer(data);
@@ -189,7 +188,7 @@ utils.sha256 = function sha256(data, enc) {
   var result;
 
   if (!bcoin.crypto)
-    return hash.sha256().update(data, enc).digest();
+    return bcoin.hash.sha256().update(data, enc).digest();
 
   if (Array.isArray(data))
     data = new Buffer(data);
@@ -207,7 +206,7 @@ utils.sha512hmac = function sha512hmac(data, salt) {
   var hmac, result;
 
   if (!bcoin.crypto) {
-    hmac = hash.hmac(hash.sha512, utils.toArray(salt));
+    hmac = bcoin.hash.hmac(hash.sha512, utils.toArray(salt));
     return hmac.update(utils.toArray(data)).digest();
   }
 
@@ -1511,3 +1510,18 @@ utils.forEach = function forEach(arr, iter, callback) {
 utils.mb = function mb(size) {
   return size / 1024 / 1024 | 0;
 };
+
+utils.inherits = function inherits(obj, from) {
+  if (Object.create) {
+    obj.prototype = Object.create(from.prototype, {
+      constructor: {
+        value: obj,
+        enumerable: false
+      }
+    });
+    return;
+  }
+  var f = function() {};
+  f.prototype = from.prototype;
+  obj.prototype = new f;
+};
diff --git a/lib/bcoin/wallet.js b/lib/bcoin/wallet.js
index 698a84c1..b30f141b 100644
--- a/lib/bcoin/wallet.js
+++ b/lib/bcoin/wallet.js
@@ -5,9 +5,7 @@
  */
 
 var bcoin = require('../bcoin');
-var hash = require('hash.js');
 var bn = require('bn.js');
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 var utils = bcoin.utils;
 var assert = utils.assert;
@@ -101,7 +99,7 @@ function Wallet(options) {
   }, this);
 }
 
-inherits(Wallet, EventEmitter);
+utils.inherits(Wallet, EventEmitter);
 
 Wallet.prototype._init = function _init() {
   var self = this;
diff --git a/lib/bcoin/walletdb.js b/lib/bcoin/walletdb.js
index dbe90118..424625c2 100644
--- a/lib/bcoin/walletdb.js
+++ b/lib/bcoin/walletdb.js
@@ -4,7 +4,6 @@
  * https://github.com/indutny/bcoin
  */
 
-var inherits = require('inherits');
 var EventEmitter = require('events').EventEmitter;
 
 var bcoin = require('../bcoin');
@@ -52,11 +51,13 @@ function WalletDB(options) {
   this._init();
 }
 
-inherits(WalletDB, EventEmitter);
+utils.inherits(WalletDB, EventEmitter);
 
 WalletDB._db = {};
 
 WalletDB.prototype._init = function _init() {
+  var levelup;
+
   if (this.type === 'file' && !bcoin.fs) {
     this.type = 'leveldb';
     utils.debug('`fs` module not available. Falling back to leveldb.');
@@ -84,6 +85,8 @@ WalletDB.prototype._init = function _init() {
 
   if (this.type === 'leveldb') {
     if (!WalletDB._db[this.file]) {
+      // Some lazy loading
+      levelup = require('levelup');
       WalletDB._db[this.file] = new levelup(this.file, {
         keyEncoding: 'ascii',
         valueEncoding: 'utf8',
diff --git a/package.json b/package.json
index a0b11036..74e26378 100644
--- a/package.json
+++ b/package.json
@@ -11,10 +11,14 @@
   "repository": "git://github.com/indutny/bcoin.git",
   "keywords": [
     "bitcoin",
+    "blockchain",
     "bcoin",
     "wallet"
   ],
   "author": "Fedor Indutny <fedor@indutny.com>",
+  "contributors": [
+    "Christopher Jeffrey <chjjeffrey@gmail.com> (https://github.com/chjj)"
+  ],
   "license": "MIT",
   "bugs": {
     "url": "https://github.com/indutny/bcoin/issues"
@@ -26,16 +30,18 @@
   "dependencies": {
     "bn.js": "4.6.3",
     "elliptic": "6.0.2",
-    "hash.js": "1.0.3",
-    "secp256k1": "3.0.0",
-    "inherits": "2.0.1",
     "leveldown": "1.4.4",
-    "level-js": "2.2.3",
-    "levelup": "1.3.1",
+    "levelup": "1.3.1"
+  },
+  "optionalDependencies": {
+    "secp256k1": "3.0.0",
     "request": "2.67.0"
   },
   "devDependencies": {
+    "hash.js": "1.0.3",
+    "level-js": "2.2.3",
     "browserify": "13.0.0",
+    "uglify-js": "2.6.1",
     "mocha": "1.21.5"
   }
 }