diff --git a/.aegir.js b/.aegir.js
deleted file mode 100644
index e3151ab..0000000
--- a/.aegir.js
+++ /dev/null
@@ -1,16 +0,0 @@
-'use strict'
-
-const path = require('path')
-
-module.exports = {
-  webpack: {
-    resolve: {
-      alias: {
-        'node-forge': path.resolve(
-          path.dirname(require.resolve('libp2p-crypto')),
-          '../vendor/forge.bundle.js'
-        )
-      }
-    }
-  }
-}
diff --git a/.gitignore b/.gitignore
index d36d47f..907c78a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -26,5 +26,4 @@ build/Release
 # https://www.npmjs.org/doc/misc/npm-faq.html#should-i-check-my-node_modules-folder-into-git
 node_modules
 
-lib
-dist
\ No newline at end of file
+dist
diff --git a/.travis.yml b/.travis.yml
index dd9e44e..1e64346 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,9 +1,16 @@
 sudo: false
 language: node_js
-node_js:
-  - 4
-  - 5
-  - stable
+
+matrix:
+  include:
+  - node_js: 4
+    env: CXX=g++-4.8
+  - node_js: 6
+    env:
+      - SAUCE=true
+      - CXX=g++-4.8
+  - node_js: stable
+    env: CXX=g++-4.8
 
 # Make sure we have new NPM.
 before_install:
@@ -14,12 +21,17 @@ script:
   - npm test
   - npm run coverage
 
-addons:
-  firefox: 'latest'
-
 before_script:
   - export DISPLAY=:99.0
   - sh -e /etc/init.d/xvfb start
 
 after_success:
   - npm run coverage-publish
+
+addons:
+  firefox: latest
+  apt:
+    sources:
+      - ubuntu-toolchain-r-test
+    packages:
+      - g++-4.8
diff --git a/README.md b/README.md
index 7fc5deb..6d5f6a9 100644
--- a/README.md
+++ b/README.md
@@ -6,9 +6,40 @@
 [![Coverage Status](https://coveralls.io/repos/github/libp2p/js-peer-id/badge.svg?branch=master)](https://coveralls.io/github/libp2p/js-peer-id?branch=master)
 [![Dependency Status](https://david-dm.org/libp2p/js-peer-id.svg?style=flat-square)](https://david-dm.org/libp2p/js-peer-id)
 [![js-standard-style](https://img.shields.io/badge/code%20style-standard-brightgreen.svg?style=flat-square)](https://github.com/feross/standard)
+![](https://img.shields.io/badge/npm-%3E%3D3.0.0-orange.svg?style=flat-square)
+![](https://img.shields.io/badge/Node.js-%3E%3D4.0.0-orange.svg?style=flat-square)
+
+[![Sauce Test Status](https://saucelabs.com/browser-matrix/ipfs-js-peer-id.svg)](https://saucelabs.com/u/ipfs-js-peer-id)
 
 > [IPFS](https://github.com/ipfs/ipfs) Peer ID implementation in JavaScript.
 
+- [Description](#description)
+- [Example](#example)
+- [Installation](#installation)
+  - [npm](#npm)
+- [Setup](#setup)
+  - [Node.js](#nodejs)
+  - [Browser: Browserify, Webpack, other bundlers](#browser-browserify-webpack-other-bundlers)
+  - [Browser: `<script>` Tag](#browser-script-tag)
+- [API](#api)
+  - [Create](#create)
+    - [`new PeerId(id[, privKey, pubKey])`](#new-peeridid-privkey-pubkey)
+    - [`create([opts], callback)`](#createopts-callback)
+  - [Import](#import)
+    - [`createFromHexString(str)`](#createfromhexstringstr)
+    - [`createFromBytes(buf)`](#createfrombytesbuf)
+    - [`createFromB58String(str)`](#createfromb58stringstr)
+    - [`createFromPubKey(pubKey)`](#createfrompubkeypubkey)
+    - [`createFromPrivKey(privKey)`](#createfromprivkeyprivkey)
+    - [`createFromJSON(obj)`](#createfromjsonobj)
+  - [Export](#export)
+    - [`toHexString()`](#tohexstring)
+    - [`toBytes()`](#tobytes)
+    - [`toB58String()`](#tob58string)
+    - [`toJSON()`](#tojson)
+    - [`toPrint()`](#toprint)
+- [License](#license)
+
 # Description
 
 Generate, import, and export PeerIDs, for use with [IPFS](https://github.com/ipfs/ipfs).
@@ -26,17 +57,17 @@ to the multihash for ID generation.*
 var PeerId = require('peer-id')
 var bs58 = require('bs58')
 
-var id = PeerId.create({ bits: 32 })
-
-console.log('id        ', id.toB58String())
-console.log('priv key  ', bs58.encode(id.privKey.bytes))
-console.log('pub key   ', bs58.encode(id.pubKey.bytes))
+PeerId.create({ bits: 1024 }, (err, id) => {
+  console.log(JSON.stringify(id.toJSON(), null, 2)
+})
 ```
 
 ```
-id         QmeeLFb92nkZJGj3gXLqXrEMzCMYs6uBgQLVNbrcXEvYXk
-priv key   6ibrcPAbevzvPpkq6EA6XmLyuhmUrJrEvUfgQDtEiSEPzGnGU8Ejwf6b11DVm6opnFGo
-pub key    2BeBZVKJ9RQs4i4LbGv4ReEeuBA5dck2Gje3wt67e44XuyyPq5jE
+{
+  "id": "Qma9T5YraSnpRDZqRR4krcSJabThc8nwZuJV3LercPHufi",
+  "privKey": "CAAS4AQwggJcAgEAAoGBAMBgbIqyOL26oV3nGPBYrdpbv..",
+  "pubKey": "CAASogEwgZ8wDQYJKoZIhvcNAQEBBQADgY0AMIGJAoGBAMBgbIqyOL26oV3nGPBYrdpbvzCY..."
+}
 ```
 
 # Installation
@@ -93,11 +124,14 @@ const PeerId = require('peer-id')
 
 The key format is detailed in [libp2p-crypto](https://github.com/libp2p/js-libp2p-crypto).
 
-### `create([opts])`
+### `create([opts], callback)`
 
 Generates a new Peer ID, complete with public/private keypair.
 
 - `opts: Object`: Default: `{bits: 2048}`
+- `callback: Function`
+
+Calls back `callback` with `err, id`.
 
 ## Import
 
@@ -114,10 +148,14 @@ Creates a Peer ID from a Base58 string representing the key's multihash.
 
 ### `createFromPubKey(pubKey)`
 
+- `publicKey: Buffer`
+
 Creates a Peer ID from a buffer containing a public key.
 
 ### `createFromPrivKey(privKey)`
 
+- `privKey: Buffer`
+
 Creates a Peer ID from a buffer containing a private key.
 
 ### `createFromJSON(obj)`
@@ -126,7 +164,6 @@ Creates a Peer ID from a buffer containing a private key.
 - `obj.pubKey: String` - The public key in protobuf format, encoded in 'base64'
 - `obj.privKey: String` - The private key in protobuf format, encoded in 'base 64'
 
-
 ## Export
 
 ### `toHexString()`
diff --git a/package.json b/package.json
index 0c266bb..bfdb41b 100644
--- a/package.json
+++ b/package.json
@@ -2,9 +2,8 @@
   "name": "peer-id",
   "version": "0.7.0",
   "description": "IPFS Peer Id implementation in Node.js",
-  "main": "lib/index.js",
+  "main": "src/index.js",
   "bin": "src/bin.js",
-  "jsnext:main": "src/index.js",
   "scripts": {
     "lint": "aegir-lint",
     "build": "aegir-build",
@@ -27,24 +26,25 @@
     "test"
   ],
   "engines": {
-    "node": "^4.3.0"
+    "node": ">=4.0.0"
   },
   "bugs": {
-    "url": "https://github.com/diasdavid/js-peer-id/issues"
+    "url": "https://github.com/libp2p/js-peer-id/issues"
   },
-  "homepage": "https://github.com/diasdavid/js-peer-id",
+  "homepage": "https://github.com/libp2p/js-peer-id",
   "devDependencies": {
-    "aegir": "^8.0.0",
+    "aegir": "^9.0.1",
     "chai": "^3.5.0",
     "pre-commit": "^1.1.3"
   },
   "dependencies": {
-    "libp2p-crypto": "^0.6.1",
+    "async": "^2.0.1",
+    "libp2p-crypto": "^0.7.0",
     "multihashes": "^0.2.2"
   },
   "repository": {
     "type": "git",
-    "url": "https://github.com/diasdavid/js-peer-id.git"
+    "url": "https://github.com/libp2p/js-peer-id.git"
   },
   "contributors": [
     "David Dias <daviddias.p@gmail.com>",
@@ -53,4 +53,4 @@
     "dignifiedquire <dignifiedquire@gmail.com>",
     "nginnever <ginneversource@gmail.com>"
   ]
-}
\ No newline at end of file
+}
diff --git a/src/bin.js b/src/bin.js
index b17b525..9388e68 100755
--- a/src/bin.js
+++ b/src/bin.js
@@ -4,4 +4,10 @@
 
 const PeerId = require('./index.js')
 
-console.log(JSON.stringify(PeerId.create().toJSON(), null, '  '))
+PeerId.create((err, id) => {
+  if (err) {
+    throw err
+  }
+
+  console.log(JSON.stringify(id.toJSON(), null, 2))
+})
diff --git a/src/index.js b/src/index.js
index 7c58b4a..08dd49e 100644
--- a/src/index.js
+++ b/src/index.js
@@ -7,28 +7,25 @@
 const mh = require('multihashes')
 const crypto = require('libp2p-crypto')
 const assert = require('assert')
+const waterfall = require('async/waterfall')
 
 class PeerId {
   constructor (id, privKey, pubKey) {
     assert(Buffer.isBuffer(id), 'invalid id provided')
 
-    if (pubKey) {
-      assert(id.equals(pubKey.hash()), 'inconsistent arguments')
-    }
-
-    if (privKey) {
-      assert(id.equals(privKey.public.hash()), 'inconsistent arguments')
-    }
-
     if (privKey && pubKey) {
       assert(privKey.public.bytes.equals(pubKey.bytes), 'inconsistent arguments')
     }
 
     this.id = id
-    this.privKey = privKey
+    this._privKey = privKey
     this._pubKey = pubKey
   }
 
+  get privKey () {
+    return this._privKey
+  }
+
   get pubKey () {
     if (this._pubKey) {
       return this._pubKey
@@ -88,13 +85,26 @@ exports = module.exports = PeerId
 exports.Buffer = Buffer
 
 // generation
-exports.create = function (opts) {
+exports.create = function (opts, callback) {
+  if (typeof opts === 'function') {
+    callback = opts
+    opts = {}
+  }
   opts = opts || {}
   opts.bits = opts.bits || 2048
 
-  const privKey = crypto.generateKeyPair('RSA', opts.bits)
+  waterfall([
+    (cb) => crypto.generateKeyPair('RSA', opts.bits, cb),
+    (privKey, cb) => privKey.public.hash((err, digest) => {
+      cb(err, digest, privKey)
+    })
+  ], (err, digest, privKey) => {
+    if (err) {
+      return callback(err)
+    }
 
-  return new PeerId(privKey.public.hash(), privKey)
+    callback(null, new PeerId(digest, privKey))
+  })
 }
 
 exports.createFromHexString = function (str) {
@@ -110,39 +120,94 @@ exports.createFromB58String = function (str) {
 }
 
 // Public Key input will be a buffer
-exports.createFromPubKey = function (key) {
+exports.createFromPubKey = function (key, callback) {
   let buf = key
   if (typeof buf === 'string') {
     buf = new Buffer(key, 'base64')
   }
+
+  if (typeof callback !== 'function') {
+    throw new Error('callback is required')
+  }
+
   const pubKey = crypto.unmarshalPublicKey(buf)
-  return new PeerId(pubKey.hash(), null, pubKey)
+  pubKey.hash((err, digest) => {
+    if (err) {
+      return callback(err)
+    }
+
+    callback(null, new PeerId(digest, null, pubKey))
+  })
 }
 
 // Private key input will be a string
-exports.createFromPrivKey = function (key) {
+exports.createFromPrivKey = function (key, callback) {
   let buf = key
   if (typeof buf === 'string') {
     buf = new Buffer(key, 'base64')
   }
 
-  const privKey = crypto.unmarshalPrivateKey(buf)
-  return new PeerId(privKey.public.hash(), privKey)
-}
+  if (typeof callback !== 'function') {
+    throw new Error('callback is required')
+  }
 
-exports.createFromJSON = function (obj) {
-  let priv
-  let pub
+  waterfall([
+    (cb) => crypto.unmarshalPrivateKey(buf, cb),
+    (privKey, cb) => privKey.public.hash((err, digest) => {
+      cb(err, digest, privKey)
+    })
+  ], (err, digest, privKey) => {
+    if (err) {
+      return callback(err)
+    }
 
-  if (obj.privKey) {
-    priv = crypto.unmarshalPrivateKey(new Buffer(obj.privKey, 'base64'))
-  }
+    callback(null, new PeerId(digest, privKey))
+  })
+}
 
-  if (obj.pubKey) {
-    pub = crypto.unmarshalPublicKey(new Buffer(obj.pubKey, 'base64'))
+exports.createFromJSON = function (obj, callback) {
+  if (typeof callback !== 'function') {
+    throw new Error('callback is required')
   }
 
-  return new PeerId(mh.fromB58String(obj.id), priv, pub)
+  const id = mh.fromB58String(obj.id)
+  const rawPrivKey = obj.privKey && new Buffer(obj.privKey, 'base64')
+  const rawPubKey = obj.pubKey && new Buffer(obj.pubKey, 'base64')
+  const pub = rawPubKey && crypto.unmarshalPublicKey(rawPubKey)
+
+  if (rawPrivKey) {
+    waterfall([
+      (cb) => crypto.unmarshalPrivateKey(rawPrivKey, cb),
+      (priv, cb) => priv.public.hash((err, digest) => {
+        cb(err, digest, priv)
+      }),
+      (privDigest, priv, cb) => {
+        if (pub) {
+          pub.hash((err, pubDigest) => {
+            cb(err, privDigest, priv, pubDigest)
+          })
+        } else {
+          cb(null, privDigest, priv)
+        }
+      }
+    ], (err, privDigest, priv, pubDigest) => {
+      if (err) {
+        return callback(err)
+      }
+
+      if (pub && !privDigest.equals(pubDigest)) {
+        return callback(new Error('Public and private key do not match'))
+      }
+
+      if (id && !privDigest.equals(id)) {
+        return callback(new Error('Id and private key do not match'))
+      }
+
+      callback(null, new PeerId(id, priv, pub))
+    })
+  } else {
+    callback(null, new PeerId(id, null, pub))
+  }
 }
 
 function toB64Opt (val) {
diff --git a/test/index.spec.js b/test/index.spec.js
index 233a5ed..e4e19b8 100644
--- a/test/index.spec.js
+++ b/test/index.spec.js
@@ -1,9 +1,11 @@
+/* eslint max-nested-callbacks: ["error", 8] */
 /* eslint-env mocha */
 'use strict'
 
 const expect = require('chai').expect
 const crypto = require('libp2p-crypto')
 const mh = require('multihashes')
+const parallel = require('async/parallel')
 
 const PeerId = require('../src')
 
@@ -19,9 +21,12 @@ describe('PeerId', () => {
     expect(PeerId).to.throw(Error)
   })
 
-  it('create a new id', () => {
-    const id = PeerId.create()
-    expect(id.toB58String().length).to.equal(46)
+  it('create a new id', (done) => {
+    PeerId.create((err, id) => {
+      expect(err).to.not.exist
+      expect(id.toB58String().length).to.equal(46)
+      done()
+    })
   })
 
   it('recreate an Id from Hex string', () => {
@@ -39,38 +44,60 @@ describe('PeerId', () => {
     expect(testIdB58String).to.equal(id.toB58String())
   })
 
-  it('Recreate from a Public Key', () => {
-    const id = PeerId.createFromPubKey(testId.pubKey)
-    expect(testIdB58String).to.equal(id.toB58String())
+  it('Recreate from a Public Key', (done) => {
+    PeerId.createFromPubKey(testId.pubKey, (err, id) => {
+      expect(err).to.not.exist
+      expect(testIdB58String).to.equal(id.toB58String())
+      done()
+    })
   })
 
-  it('Recreate from a Private Key', () => {
-    const id = PeerId.createFromPrivKey(testId.privKey)
-    expect(testIdB58String).to.equal(id.toB58String())
-
-    const id2 = PeerId.createFromPrivKey(new Buffer(testId.privKey, 'base64'))
-    expect(testIdB58String).to.equal(id2.toB58String())
+  it('Recreate from a Private Key', (done) => {
+    PeerId.createFromPrivKey(testId.privKey, (err, id) => {
+      expect(err).to.not.exist
+      expect(testIdB58String).to.equal(id.toB58String())
+
+      const encoded = new Buffer(testId.privKey, 'base64')
+      PeerId.createFromPrivKey(encoded, (err, id2) => {
+        expect(err).to.not.exist
+        expect(testIdB58String).to.equal(id2.toB58String())
+        done()
+      })
+    })
   })
 
-  it('Compare generated ID with one created from PubKey', () => {
-    const id1 = PeerId.create()
-    const id2 = PeerId.createFromPubKey(id1.marshalPubKey())
-    expect(id1.id).to.be.eql(id2.id)
-  })
+  it('Compare generated ID with one created from PubKey', (done) => {
+    PeerId.create((err, id1) => {
+      expect(err).to.not.exist
 
-  it('Non-default # of bits', () => {
-    const shortId = PeerId.create({ bits: 128 })
-    const longId = PeerId.create({ bits: 256 })
-    expect(shortId.privKey.bytes.length).is.below(longId.privKey.bytes.length)
+      PeerId.createFromPubKey(id1.marshalPubKey(), (err, id2) => {
+        expect(err).to.not.exist
+        expect(id1.id).to.be.eql(id2.id)
+        done()
+      })
+    })
   })
 
-  it('Pretty printing', () => {
-    const id = PeerId.createFromPrivKey(testId.privKey)
-    const out = id.toPrint()
+  it('Non-default # of bits', (done) => {
+    PeerId.create({ bits: 1024 }, (err, shortId) => {
+      expect(err).to.not.exist
+      PeerId.create({ bits: 4096 }, (err, longId) => {
+        expect(err).to.not.exist
+        expect(shortId.privKey.bytes.length).is.below(longId.privKey.bytes.length)
+        done()
+      })
+    })
+  })
 
-    expect(out.id).to.equal(testIdB58String)
-    expect(out.privKey).to.equal(testId.privKey)
-    expect(out.pubKey).to.equal(testId.pubKey)
+  it('Pretty printing', (done) => {
+    PeerId.create((err, id1) => {
+      expect(err).to.not.exist
+      PeerId.createFromPrivKey(id1.toPrint().privKey, (err, id2) => {
+        expect(err).to.not.exist
+        expect(id1.toPrint()).to.be.eql(id2.toPrint())
+        done()
+      })
+    })
   })
 
   it('toBytes', () => {
@@ -78,90 +105,118 @@ describe('PeerId', () => {
     expect(id.toBytes().toString('hex')).to.equal(testIdBytes.toString('hex'))
   })
 
-  describe('toJSON', () => {
-    it('full node', () => {
-      const id = PeerId.create({bits: 64})
-      expect(
-        id.toB58String()
-      ).to.equal(
-        PeerId.createFromJSON(id.toJSON()).toB58String()
-      )
-      expect(
-        id.privKey.bytes
-      ).to.deep.equal(
-        PeerId.createFromJSON(id.toJSON()).privKey.bytes
-      )
-      expect(
-        id.pubKey.bytes
-      ).to.deep.equal(
-        PeerId.createFromJSON(id.toJSON()).pubKey.bytes
-      )
+  describe('fromJSON', () => {
+    it('full node', (done) => {
+      PeerId.create({bits: 1024}, (err, id) => {
+        expect(err).to.not.exist
+
+        PeerId.createFromJSON(id.toJSON(), (err, other) => {
+          expect(err).to.not.exist
+          expect(
+            id.toB58String()
+          ).to.equal(
+            other.toB58String()
+          )
+          expect(
+            id.privKey.bytes
+          ).to.deep.equal(
+            other.privKey.bytes
+          )
+          expect(
+            id.pubKey.bytes
+          ).to.deep.equal(
+            other.pubKey.bytes
+          )
+          done()
+        })
+      })
     })
 
-    it('only id', () => {
-      const key = crypto.generateKeyPair('RSA', 64)
-      const id = PeerId.createFromBytes(key.public.hash())
-      expect(
-        id.toB58String()
-      ).to.equal(
-        PeerId.createFromJSON(id.toJSON()).toB58String()
-      )
-
-      expect(id.privKey).to.not.exist
-      expect(id.pubKey).to.not.exist
+    it('only id', (done) => {
+      crypto.generateKeyPair('RSA', 1024, (err, key) => {
+        expect(err).to.not.exist
+        key.public.hash((err, digest) => {
+          expect(err).to.not.exist
+
+          const id = PeerId.createFromBytes(digest)
+          expect(id.privKey).to.not.exist
+          expect(id.pubKey).to.not.exist
+
+          PeerId.createFromJSON(id.toJSON(), (err, other) => {
+            expect(err).to.not.exist
+            expect(
+              id.toB58String()
+            ).to.equal(
+              other.toB58String()
+            )
+            done()
+          })
+        })
+      })
     })
 
-    it('go interop', () => {
-      const id = PeerId.createFromJSON(goId)
-
-      expect(
-        mh.toB58String(id.privKey.public.hash())
-      ).to.be.eql(
-        goId.id
-      )
+    it('go interop', (done) => {
+      PeerId.createFromJSON(goId, (err, id) => {
+        expect(err).to.not.exist
+        id.privKey.public.hash((err, digest) => {
+          expect(err).to.not.exist
+          expect(
+            mh.toB58String(digest)
+          ).to.be.eql(
+            goId.id
+          )
+          done()
+        })
+      })
     })
   })
 
   describe('throws on inconsistent data', () => {
-    const k1 = crypto.generateKeyPair('RSA', 64)
-    const k2 = crypto.generateKeyPair('RSA', 64)
-    const k3 = crypto.generateKeyPair('RSA', 64)
-
-    it('missmatch id - private key', () => {
-      expect(
-        () => new PeerId(k1.public.hash(), k2)
-      ).to.throw(
-        /inconsistent arguments/
-      )
+    let k1, k2, k3
+    before((done) => {
+      parallel([
+        (cb) => crypto.generateKeyPair('RSA', 1024, cb),
+        (cb) => crypto.generateKeyPair('RSA', 1024, cb),
+        (cb) => crypto.generateKeyPair('RSA', 1024, cb)
+      ], (err, keys) => {
+        if (err) {
+          return done(err)
+        }
+
+        k1 = keys[0]
+        k2 = keys[1]
+        k3 = keys[2]
+        done()
+      })
     })
 
-    it('missmatch id - public key', () => {
-      expect(
-        () => new PeerId(k1.public.hash(), null, k2.public)
-      ).to.throw(
-        /inconsistent arguments/
-      )
+    it('missmatch private - public key', (done) => {
+      k1.public.hash((err, digest) => {
+        expect(err).to.not.exist
+        expect(
+          () => new PeerId(digest, k1, k2.public)
+        ).to.throw(
+            /inconsistent arguments/
+        )
+        done()
+      })
     })
 
-    it('missmatch private - public key', () => {
-      expect(
-        () => new PeerId(k1.public.hash(), k1, k2.public)
-      ).to.throw(
-        /inconsistent arguments/
-      )
-    })
-
-    it('missmatch id - private - public key', () => {
-      expect(
-        () => new PeerId(k1.public.hash(), k1, k3.public)
-      ).to.throw(
-        /inconsistent arguments/
-      )
+    it('missmatch id - private - public key', (done) => {
+      k1.public.hash((err, digest) => {
+        expect(err).to.not.exist
+        expect(
+          () => new PeerId(digest, k1, k3.public)
+        ).to.throw(
+            /inconsistent arguments/
+        )
+        done()
+      })
     })
 
     it('invalid id', () => {
       expect(
-        () => new PeerId(k1.public.hash().toString())
+        () => new PeerId('hello world')
       ).to.throw(
         /invalid id/
       )