diff --git a/lib/bcoin/env.js b/lib/bcoin/env.js
index ccc305f0..efb14b1c 100644
--- a/lib/bcoin/env.js
+++ b/lib/bcoin/env.js
@@ -91,7 +91,6 @@ var global = utils.global;
  * @property {Function} chain - {@link Chain} constructor.
  * @property {Function} mempool - {@link Mempool} constructor.
  * @property {Function} mempoolentry - {@link MempoolEntry} constructor.
- * @property {Function} keypair - {@link KeyPair} constructor.
  * @property {Function} hd - {@link HD} constructor.
  * @property {Function} address - {@link Address} constructor.
  * @property {Function} wallet - {@link Wallet} constructor.
@@ -164,9 +163,8 @@ function Environment() {
   this.chain = require('./chain');
   this.mempool = require('./mempool');
   this.mempoolentry = this.mempool.MempoolEntry;
-  this.keypair = require('./keypair');
-  this.hd = require('./hd');
   this.keyring = require('./keyring');
+  this.hd = require('./hd');
   this.wallet = require('./wallet');
   this.account = this.wallet.Account;
   this.walletdb = require('./walletdb');
diff --git a/lib/bcoin/hd.js b/lib/bcoin/hd.js
index 779a6b2f..cc059edc 100644
--- a/lib/bcoin/hd.js
+++ b/lib/bcoin/hd.js
@@ -84,7 +84,7 @@ var ec = require('./ec');
 var assert = utils.assert;
 var constants = bcoin.protocol.constants;
 var networks = bcoin.protocol.network;
-var KeyPair = bcoin.keypair;
+var KeyRing = bcoin.keyring;
 var LRU = require('./lru');
 var BufferWriter = require('./writer');
 var BufferReader = require('./reader');
@@ -2141,7 +2141,7 @@ HDPublicKey.isHDPublicKey = function isHDPublicKey(obj) {
    * @returns {Buffer}
    */
 
-  HD.prototype.getPrivateKey = KeyPair.prototype.getPrivateKey;
+  HD.prototype.getPrivateKey = KeyRing.prototype.getPrivateKey;
 
   /**
    * Get public key.
@@ -2151,7 +2151,7 @@ HDPublicKey.isHDPublicKey = function isHDPublicKey(obj) {
    * @returns {Buffer}
    */
 
-  HD.prototype.getPublicKey = KeyPair.prototype.getPublicKey;
+  HD.prototype.getPublicKey = KeyRing.prototype.getPublicKey;
 
   /**
    * Sign message.
@@ -2161,7 +2161,7 @@ HDPublicKey.isHDPublicKey = function isHDPublicKey(obj) {
    * @returns {Buffer}
    */
 
-  HD.prototype.sign = KeyPair.prototype.sign;
+  HD.prototype.sign = KeyRing.prototype.sign;
 
   /**
    * Verify message.
@@ -2172,7 +2172,16 @@ HDPublicKey.isHDPublicKey = function isHDPublicKey(obj) {
    * @returns {Boolean}
    */
 
-  HD.prototype.verify = KeyPair.prototype.verify;
+  HD.prototype.verify = KeyRing.prototype.verify;
+
+  /**
+   * Convert HDPrivateKey to a KeyRing.
+   * @returns {KeyRing}
+   */
+
+  HD.prototype.toKeyRing = function toKeyRing() {
+    return new KeyRing(this.privateKey || this.publicKey, this.network);
+  };
 
   /**
    * Whether the key prefers a
@@ -2186,22 +2195,13 @@ HDPublicKey.isHDPublicKey = function isHDPublicKey(obj) {
   HD.prototype.compressed = true;
 });
 
-/**
- * Convert HDPrivateKey to a KeyPair.
- * @returns {KeyPair}
- */
-
-HDPrivateKey.prototype.toKeyPair = function toKeyPair() {
-  return new KeyPair(this);
-};
-
 /**
  * Convert HDPrivateKey to CBitcoinSecret.
  * @returns {Base58String}
  */
 
 HDPrivateKey.prototype.toSecret = function toSecret(network) {
-  return this.toKeyPair().toSecret(network);
+  return this.toKeyRing().toSecret(network);
 };
 
 /*
diff --git a/lib/bcoin/http/rpc.js b/lib/bcoin/http/rpc.js
index 8f646b38..8b792cc1 100644
--- a/lib/bcoin/http/rpc.js
+++ b/lib/bcoin/http/rpc.js
@@ -2373,11 +2373,11 @@ RPC.prototype.signmessagewithprivkey = function signmessagewithprivkey(args, cal
   key = toString(args[0]);
   msg = toString(args[1]);
 
-  key = bcoin.keypair.fromSecret(key).getPrivateKey();
+  key = bcoin.keyring.fromSecret(key);
   msg = new Buffer(RPC.magic + msg, 'utf8');
   msg = utils.hash256(msg);
 
-  sig = bcoin.ec.sign(msg, key);
+  sig = key.sign(msg);
 
   callback(null, sig.toString('base64'));
 };
diff --git a/lib/bcoin/keypair.js b/lib/bcoin/keypair.js
deleted file mode 100644
index 3d87616f..00000000
--- a/lib/bcoin/keypair.js
+++ /dev/null
@@ -1,372 +0,0 @@
-/*!
- * keypair.js - keypair object for bcoin
- * Copyright (c) 2014-2015, Fedor Indutny (MIT License)
- * Copyright (c) 2014-2016, Christopher Jeffrey (MIT License).
- * https://github.com/bcoin-org/bcoin
- */
-
-'use strict';
-
-var bcoin = require('./env');
-var utils = require('./utils');
-var assert = utils.assert;
-var network = bcoin.protocol.network;
-var BufferWriter = require('./writer');
-var BufferReader = require('./reader');
-
-/**
- * Represents an ecdsa keypair.
- * @exports KeyPair
- * @constructor
- * @param {Object} options
- * @param {Buffer?} options.privateKey
- * @param {Buffer?} options.publicKey
- * @param {Boolean?} options.compressed
- * @param {(Network|NetworkType)?} options.network
- * @property {Buffer} privateKey
- * @property {Buffer} publicKey
- * @property {Boolean} compressed
- * @property {Network} network
- */
-
-function KeyPair(options) {
-  if (!(this instanceof KeyPair))
-    return new KeyPair(options);
-
-  this.network = bcoin.network.get();
-  this.compressed = true;
-  this.privateKey = null;
-  this.publicKey = null;
-
-  if (options)
-    this.fromOptions(options);
-}
-
-/**
- * Inject properties from options object.
- * @private
- * @param {Object} options
- */
-
-KeyPair.prototype.fromOptions = function fromOptions(options) {
-  if (options.privateKey) {
-    return this.fromPrivate(
-      options.privateKey,
-      options.compressed,
-      options.network);
-  }
-
-  if (options.publicKey)
-    return this.fromPublic(options.publicKey, options.network);
-
-  throw new Error('Must provide a key.');
-};
-
-/**
- * Instantiate key pair from options object.
- * @param {Object} options
- * @returns {KeyPair}
- */
-
-KeyPair.fromOptions = function fromOptions(options) {
-  return new KeyPair().fromOptions(options);
-};
-
-/**
- * Generate a keypair.
- * @param {(Network|NetworkType)?} network
- * @returns {KeyPair}
- */
-
-KeyPair.generate = function(network) {
-  var key = new KeyPair();
-  key.network = bcoin.network.get(network);
-  key.privateKey = bcoin.ec.generatePrivateKey();
-  key.publicKey = bcoin.ec.publicKeyCreate(key.privateKey, true);
-  return key;
-};
-
-/**
- * Inject data from private key.
- * @private
- * @param {Buffer} privateKey
- * @param {Boolean?} compressed
- * @param {(NetworkType|Network}) network
- */
-
-KeyPair.prototype.fromPrivate = function fromPrivate(privateKey, compressed, network) {
-  assert(Buffer.isBuffer(privateKey));
-  this.network = bcoin.network.get(network);
-  this.privateKey = privateKey;
-  this.compressed = compressed !== false;
-  this.publicKey = bcoin.ec.publicKeyCreate(this.privateKey, this.compressed);
-  return this;
-};
-
-/**
- * Instantiate key pair from a private key.
- * @param {Buffer} privateKey
- * @param {Boolean?} compressed
- * @param {(NetworkType|Network}) network
- * @returns {KeyPair}
- */
-
-KeyPair.fromPrivate = function fromPrivate(privateKey, compressed, network) {
-  return new KeyPair().fromPrivate(privateKey, compressed, network);
-};
-
-/**
- * Inject data from public key.
- * @private
- * @param {Buffer} privateKey
- * @param {(NetworkType|Network}) network
- */
-
-KeyPair.prototype.fromPublic = function fromPublic(publicKey, network) {
-  assert(Buffer.isBuffer(publicKey));
-  this.network = bcoin.network.get(network);
-  this.publicKey = publicKey;
-  this.compressed = publicKey[0] <= 0x03;
-  return this;
-};
-
-/**
- * Instantiate key pair from a public key.
- * @param {Buffer} publicKey
- * @param {(NetworkType|Network}) network
- * @returns {KeyPair}
- */
-
-KeyPair.fromPublic = function fromPublic(publicKey, network) {
-  return new KeyPair().fromPublic(publicKey, network);
-};
-
-/**
- * Sign a message.
- * @param {Buffer} msg
- * @returns {Buffer} Signature in DER format.
- */
-
-KeyPair.prototype.sign = function sign(msg) {
-  assert(this.privateKey, 'Cannot sign without private key.');
-  return bcoin.ec.sign(msg, this.getPrivateKey());
-};
-
-/**
- * Verify a message.
- * @param {Buffer} msg
- * @param {Buffer} sig - Signature in DER format.
- * @returns {Boolean}
- */
-
-KeyPair.prototype.verify = function verify(msg, sig) {
-  return bcoin.ec.verify(msg, sig, this.getPublicKey());
-};
-
-/**
- * Get private key.
- * @param {String?} enc - Can be `"hex"`, `"base58"`, or `null`.
- * @returns {Buffer} Private key.
- */
-
-KeyPair.prototype.getPrivateKey = function getPrivateKey(enc) {
-  if (!this.privateKey)
-    return;
-
-  if (enc === 'base58')
-    return this.toSecret();
-
-  if (enc === 'hex')
-    return this.privateKey.toString('hex');
-
-  return this.privateKey;
-};
-
-/**
- * Get public key.
- * @param {String?} enc - Can be `"hex"`, or `null`.
- * @returns {Buffer} Public key.
- */
-
-KeyPair.prototype.getPublicKey = function getPublicKey(enc) {
-  if (enc === 'base58')
-    return utils.toBase58(this.publicKey);
-
-  if (enc === 'hex')
-    return this.publicKey.toString('hex');
-
-  return this.publicKey;
-};
-
-/**
- * Convert key to a CBitcoinSecret.
- * @param {(Network|NetworkType)?} network
- * @returns {Buffer}
- */
-
-KeyPair.prototype.toRaw = function toRaw(network, writer) {
-  var p = new BufferWriter(writer);
-
-  assert(this.privateKey, 'Cannot serialize without private key.');
-
-  if (!network)
-    network = this.network;
-
-  network = bcoin.network.get(network);
-
-  p.writeU8(network.keyPrefix.privkey);
-  p.writeBytes(this.getPrivateKey());
-
-  if (this.compressed)
-    p.writeU8(1);
-
-  p.writeChecksum();
-
-  if (!writer)
-    p = p.render();
-
-  return p;
-};
-
-/**
- * Convert key to a CBitcoinSecret.
- * @param {(Network|NetworkType)?} network
- * @returns {Base58String}
- */
-
-KeyPair.prototype.toSecret = function toSecret(network) {
-  return utils.toBase58(this.toRaw(network));
-};
-
-/**
- * Inject properties from serialized CBitcoinSecret.
- * @private
- * @param {Buffer} data
- */
-
-KeyPair.prototype.fromRaw = function fromRaw(data) {
-  var p = new BufferReader(data, true);
-  var i, prefix, version, type, key, compressed;
-
-  version = p.readU8();
-
-  for (i = 0; i < network.types.length; i++) {
-    type = network.types[i];
-    prefix = network[type].keyPrefix.privkey;
-    if (version === prefix)
-      break;
-  }
-
-  assert(i < network.types.length, 'Network not found.');
-
-  key = p.readBytes(32);
-
-  if (p.left() > 4) {
-    assert(p.readU8() === 1, 'Bad compression flag.');
-    compressed = true;
-  } else {
-    compressed = false;
-  }
-
-  p.verifyChecksum();
-
-  assert(bcoin.ec.privateKeyVerify(key));
-
-  return this.fromPrivate(key, compressed, type);
-};
-
-/**
- * Inject properties from serialized CBitcoinSecret.
- * @private
- * @param {Base58String} secret
- */
-
-KeyPair.prototype.fromSecret = function fromSecret(secret) {
-  return this.fromRaw(utils.fromBase58(secret));
-};
-
-/**
- * Instantiate a key pair from a serialized CBitcoinSecret.
- * @param {Buffer} data
- * @returns {KeyPair}
- */
-
-KeyPair.fromRaw = function fromRaw(data, enc) {
-  if (typeof data === 'string')
-    data = new Buffer(data, enc);
-  return new KeyPair().fromRaw(data);
-};
-
-/**
- * Instantiate a key pair from a serialized CBitcoinSecret.
- * @param {Base58String} secret
- * @returns {KeyPair}
- */
-
-KeyPair.fromSecret = function fromSecret(secret) {
-  return new KeyPair().fromSecret(secret);
-};
-
-/**
- * Convert the keypair to an object suitable
- * for JSON serialization.
- * @returns {Object}
- */
-
-KeyPair.prototype.toJSON = function toJSON() {
-  return {
-    network: this.network.type,
-    compressed: this.compressed,
-    privateKey: this.privateKey ? this.toSecret() : null,
-    publicKey: this.getPublicKey('base58')
-  };
-};
-
-/**
- * Inject properties from json object.
- * @private
- * @param {Object} json
- */
-
-KeyPair.prototype.fromJSON = function fromJSON(json) {
-  var key;
-
-  if (json.privateKey)
-    return this.fromSecret(json.privateKey);
-
-  if (json.publicKey) {
-    key = utils.fromBase58(json.publicKey);
-    assert(bcoin.ec.publicKeyVerify(key));
-    return this.fromPublic(key, json.network);
-  }
-
-  assert(false, 'Could not parse KeyPair JSON.');
-};
-
-/**
- * Instantiate a key pair from a jsonified object.
- * @param {Object} json - The jsonified key pair object.
- * @returns {KeyPair}
- */
-
-KeyPair.fromJSON = function fromJSON(json) {
-  return new KeyPair().fromJSON(json);
-};
-
-/**
- * Test whether an object is a key pair.
- * @param {Object?} obj
- * @returns {Boolean}
- */
-
-KeyPair.isKeyPair = function isKeyPair(obj) {
-  return obj
-    && obj.privateKey !== undefined
-    && typeof obj.fromSecret === 'function';
-};
-
-/*
- * Expose
- */
-
-module.exports = KeyPair;
diff --git a/lib/bcoin/keyring.js b/lib/bcoin/keyring.js
index 1f61a467..d923fc19 100644
--- a/lib/bcoin/keyring.js
+++ b/lib/bcoin/keyring.js
@@ -288,6 +288,25 @@ KeyRing.fromSecret = function fromSecret(data) {
   return new KeyRing().fromSecret(data);
 };
 
+/**
+ * Get private key.
+ * @param {String?} enc - Can be `"hex"`, `"base58"`, or `null`.
+ * @returns {Buffer} Private key.
+ */
+
+KeyRing.prototype.getPrivateKey = function getPrivateKey(enc) {
+  if (!this.privateKey)
+    return;
+
+  if (enc === 'base58')
+    return this.toSecret();
+
+  if (enc === 'hex')
+    return this.privateKey.toString('hex');
+
+  return this.privateKey;
+};
+
 /**
  * Get public key.
  * @param {String?} enc - `"hex"` or `null`.
diff --git a/lib/bcoin/mtx.js b/lib/bcoin/mtx.js
index f4a2881f..67301b71 100644
--- a/lib/bcoin/mtx.js
+++ b/lib/bcoin/mtx.js
@@ -387,7 +387,7 @@ MTX.prototype.scriptVector = function scriptVector(prev, vector, ring) {
 /**
  * Sign an input.
  * @param {Number} index - Index of input being signed.
- * @param {HDPrivateKey|KeyPair|Buffer} key - Private key.
+ * @param {Buffer} key - Private key.
  * @param {SighashType} type
  * @returns {Boolean} Whether the input was able to be signed.
  */
diff --git a/lib/bcoin/protocol/framer.js b/lib/bcoin/protocol/framer.js
index 9745bbf8..ed328fbb 100644
--- a/lib/bcoin/protocol/framer.js
+++ b/lib/bcoin/protocol/framer.js
@@ -707,7 +707,6 @@ Framer.addr = function addr(hosts, writer) {
 /**
  * Create an alert packet (without a header).
  * @param {AlertPacket} data
- * @param {Buffer|KeyPair} key
  * @param {BufferWriter?} writer - A buffer writer to continue writing from.
  * @returns {Buffer} Returns a BufferWriter if `writer` was passed in.
  */