diff --git a/package.json b/package.json
index 3996c800c0..b7cd5777c4 100644
--- a/package.json
+++ b/package.json
@@ -4,6 +4,15 @@
   "description": "JavaScript implementation of libp2p, a modular peer to peer network stack",
   "leadMaintainer": "Jacob Heun <jacobheun@gmail.com>",
   "main": "src/index.js",
+  "types": "dist/src/index.d.ts",
+  "typesVersions": {
+    "*": {
+      "src/*": [
+        "dist/src/*",
+        "dist/src/*/index"
+      ]
+    }
+  },
   "files": [
     "dist",
     "src"
@@ -15,6 +24,7 @@
     "test:node": "aegir test -t node -f \"./test/**/*.{node,spec}.js\"",
     "test:browser": "aegir test -t browser",
     "test:examples": "cd examples && npm run test:all",
+    "test:types": "aegir ts -p check",
     "release": "aegir release -t node -t browser",
     "release-minor": "aegir release --type minor -t node -t browser",
     "release-major": "aegir release --type major -t node -t browser",
@@ -88,7 +98,7 @@
   "devDependencies": {
     "@nodeutils/defaults-deep": "^1.1.0",
     "abortable-iterator": "^3.0.0",
-    "aegir": "^27.0.0",
+    "aegir": "^29.1.0",
     "chai-bytes": "^0.1.2",
     "chai-string": "^1.5.0",
     "delay": "^4.3.0",
diff --git a/src/address-manager/index.js b/src/address-manager/index.js
index d4811be72c..5c9874af33 100644
--- a/src/address-manager/index.js
+++ b/src/address-manager/index.js
@@ -1,9 +1,5 @@
 'use strict'
 
-const debug = require('debug')
-const log = debug('libp2p:addresses')
-log.error = debug('libp2p:addresses:error')
-
 const multiaddr = require('multiaddr')
 
 /**
diff --git a/src/circuit/auto-relay.js b/src/circuit/auto-relay.js
index 7cca188735..babf4ea75a 100644
--- a/src/circuit/auto-relay.js
+++ b/src/circuit/auto-relay.js
@@ -1,8 +1,9 @@
 'use strict'
 
 const debug = require('debug')
-const log = debug('libp2p:auto-relay')
-log.error = debug('libp2p:auto-relay:error')
+const log = Object.assign(debug('libp2p:auto-relay'), {
+  error: debug('libp2p:auto-relay:err')
+})
 
 const uint8ArrayFromString = require('uint8arrays/from-string')
 const uint8ArrayToString = require('uint8arrays/to-string')
diff --git a/src/circuit/circuit/hop.js b/src/circuit/circuit/hop.js
index c653a7c9ae..7cd7ab2312 100644
--- a/src/circuit/circuit/hop.js
+++ b/src/circuit/circuit/hop.js
@@ -1,21 +1,26 @@
 'use strict'
 
 const debug = require('debug')
-const log = debug('libp2p:circuit:hop')
-log.error = debug('libp2p:circuit:hop:error')
+const log = Object.assign(debug('libp2p:circuit:hop'), {
+  error: debug('libp2p:circuit:hop:err')
+})
+const errCode = require('err-code')
 
 const PeerId = require('peer-id')
 const { validateAddrs } = require('./utils')
 const StreamHandler = require('./stream-handler')
 const { CircuitRelay: CircuitPB } = require('../protocol')
-const pipe = require('it-pipe')
-const errCode = require('err-code')
+const { pipe } = require('it-pipe')
 const { codes: Errors } = require('../../errors')
 
 const { stop } = require('./stop')
 
 const multicodec = require('./../multicodec')
 
+/**
+ * @typedef {import('libp2p-interfaces/src/connection').Connection} Connection
+ */
+
 module.exports.handleHop = async function handleHop ({
   connection,
   request,
diff --git a/src/circuit/circuit/stop.js b/src/circuit/circuit/stop.js
index 77eaa1fcc2..f9447b722d 100644
--- a/src/circuit/circuit/stop.js
+++ b/src/circuit/circuit/stop.js
@@ -1,23 +1,28 @@
 'use strict'
 
+const debug = require('debug')
+const log = Object.assign(debug('libp2p:circuit:stop'), {
+  error: debug('libp2p:circuit:stop:err')
+})
+
 const { CircuitRelay: CircuitPB } = require('../protocol')
 const multicodec = require('../multicodec')
 const StreamHandler = require('./stream-handler')
 const { validateAddrs } = require('./utils')
 
-const debug = require('debug')
-const log = debug('libp2p:circuit:stop')
-log.error = debug('libp2p:circuit:stop:error')
+/**
+ * @typedef {import('libp2p-interfaces/src/connection').Connection} Connection
+ */
 
 /**
  * Handles incoming STOP requests
  *
  * @private
- * @param {*} options
+ * @param {object} options
  * @param {Connection} options.connection
  * @param {*} options.request - The CircuitRelay protobuf request (unencoded)
  * @param {StreamHandler} options.streamHandler
- * @returns {Promise<*>} Resolves a duplex iterable
+ * @returns {Promise<*>|void} Resolves a duplex iterable
  */
 module.exports.handleStop = function handleStop ({
   connection,
@@ -44,7 +49,7 @@ module.exports.handleStop = function handleStop ({
  * Creates a STOP request
  *
  * @private
- * @param {*} options
+ * @param {object} options
  * @param {Connection} options.connection
  * @param {*} options.request - The CircuitRelay protobuf request (unencoded)
  * @returns {Promise<*>} Resolves a duplex iterable
diff --git a/src/circuit/circuit/stream-handler.js b/src/circuit/circuit/stream-handler.js
index 8b8ecf89bc..fe0adba722 100644
--- a/src/circuit/circuit/stream-handler.js
+++ b/src/circuit/circuit/stream-handler.js
@@ -1,13 +1,14 @@
 'use strict'
 
+const debug = require('debug')
+const log = Object.assign(debug('libp2p:circuit:stream-handler'), {
+  error: debug('libp2p:circuit:stream-handler:err')
+})
+
 const lp = require('it-length-prefixed')
 const handshake = require('it-handshake')
 const { CircuitRelay: CircuitPB } = require('../protocol')
 
-const debug = require('debug')
-const log = debug('libp2p:circuit:stream-handler')
-log.error = debug('libp2p:circuit:stream-handler:error')
-
 class StreamHandler {
   /**
    * Create a stream handler for connection
@@ -27,7 +28,7 @@ class StreamHandler {
    * Read and decode message
    *
    * @async
-   * @returns {void}
+   * @returns {Promise<void>}
    */
   async read () {
     const msg = await this.decoder.next()
diff --git a/src/circuit/circuit/utils.js b/src/circuit/circuit/utils.js
index be7ab35a73..669c37adc3 100644
--- a/src/circuit/circuit/utils.js
+++ b/src/circuit/circuit/utils.js
@@ -3,6 +3,10 @@
 const multiaddr = require('multiaddr')
 const { CircuitRelay } = require('../protocol')
 
+/**
+ * @typedef {import('./stream-handler')} StreamHandler
+ */
+
 /**
  * Write a response
  *
diff --git a/src/circuit/index.js b/src/circuit/index.js
index 91cb685106..447d829ac5 100644
--- a/src/circuit/index.js
+++ b/src/circuit/index.js
@@ -1,8 +1,9 @@
 'use strict'
 
 const debug = require('debug')
-const log = debug('libp2p:relay')
-log.error = debug('libp2p:relay:error')
+const log = Object.assign(debug('libp2p:relay'), {
+  error: debug('libp2p:relay:err')
+})
 
 const {
   setDelayedInterval,
diff --git a/src/circuit/listener.js b/src/circuit/listener.js
index 02e371fb8b..e591e43d11 100644
--- a/src/circuit/listener.js
+++ b/src/circuit/listener.js
@@ -1,14 +1,14 @@
 'use strict'
 
-const EventEmitter = require('events')
+const { EventEmitter } = require('events')
 const multiaddr = require('multiaddr')
 
-const debug = require('debug')
-const log = debug('libp2p:circuit:listener')
-log.err = debug('libp2p:circuit:error:listener')
+/**
+ * @typedef {import('multiaddr')} Multiaddr
+ */
 
 /**
- * @param {Libp2p} libp2p
+ * @param {import('../')} libp2p
  * @returns {Listener} a transport listener
  */
 module.exports = (libp2p) => {
diff --git a/src/connection-manager/index.js b/src/connection-manager/index.js
index 7b6ae5e414..8259e56ba5 100644
--- a/src/connection-manager/index.js
+++ b/src/connection-manager/index.js
@@ -1,8 +1,9 @@
 'use strict'
 
 const debug = require('debug')
-const log = debug('libp2p:connection-manager')
-log.error = debug('libp2p:connection-manager:error')
+const log = Object.assign(debug('libp2p:connection-manager'), {
+  error: debug('libp2p:connection-manager:err')
+})
 
 const errcode = require('err-code')
 const mergeOptions = require('merge-options')
@@ -14,7 +15,7 @@ const { EventEmitter } = require('events')
 const PeerId = require('peer-id')
 
 const {
-  ERR_INVALID_PARAMETERS
+  codes: { ERR_INVALID_PARAMETERS }
 } = require('../errors')
 
 const defaultOptions = {
@@ -187,15 +188,17 @@ class ConnectionManager extends EventEmitter {
    * @private
    */
   _checkMetrics () {
-    const movingAverages = this._libp2p.metrics.global.movingAverages
-    const received = movingAverages.dataReceived[this._options.movingAverageInterval].movingAverage()
-    this._checkMaxLimit('maxReceivedData', received)
-    const sent = movingAverages.dataSent[this._options.movingAverageInterval].movingAverage()
-    this._checkMaxLimit('maxSentData', sent)
-    const total = received + sent
-    this._checkMaxLimit('maxData', total)
-    log('metrics update', total)
-    this._timer = retimer(this._checkMetrics, this._options.pollInterval)
+    if (this._libp2p.metrics) {
+      const movingAverages = this._libp2p.metrics.global.movingAverages
+      const received = movingAverages.dataReceived[this._options.movingAverageInterval].movingAverage()
+      this._checkMaxLimit('maxReceivedData', received)
+      const sent = movingAverages.dataSent[this._options.movingAverageInterval].movingAverage()
+      this._checkMaxLimit('maxSentData', sent)
+      const total = received + sent
+      this._checkMaxLimit('maxData', total)
+      log('metrics update', total)
+      this._timer = retimer(this._checkMetrics, this._options.pollInterval)
+    }
   }
 
   /**
@@ -249,7 +252,7 @@ class ConnectionManager extends EventEmitter {
    * Get a connection with a peer.
    *
    * @param {PeerId} peerId
-   * @returns {Connection}
+   * @returns {Connection|null}
    */
   get (peerId) {
     const connections = this.getAll(peerId)
diff --git a/src/content-routing.js b/src/content-routing.js
index 75131ba1fa..185865d8ae 100644
--- a/src/content-routing.js
+++ b/src/content-routing.js
@@ -9,6 +9,7 @@ const pAny = require('p-any')
 /**
  * @typedef {import('peer-id')} PeerId
  * @typedef {import('multiaddr')} Multiaddr
+ * @typedef {import('cids')} CID
  */
 
 /**
@@ -63,7 +64,7 @@ module.exports = (node) => {
      * a provider of the given key.
      *
      * @param {CID} key - The CID key of the content to find
-     * @returns {Promise<void>}
+     * @returns {Promise<void[]>}
      */
     async provide (key) { // eslint-disable-line require-await
       if (!routers.length) {
diff --git a/src/dialer/dial-request.js b/src/dialer/dial-request.js
index d91158ed49..f906c2ba81 100644
--- a/src/dialer/dial-request.js
+++ b/src/dialer/dial-request.js
@@ -1,15 +1,13 @@
 'use strict'
 
+const errCode = require('err-code')
 const AbortController = require('abort-controller')
 const anySignal = require('any-signal')
-const debug = require('debug')
-const errCode = require('err-code')
-const log = debug('libp2p:dialer:request')
-log.error = debug('libp2p:dialer:request:error')
 const FIFO = require('p-fifo')
 const pAny = require('p-any')
 
 /**
+ * @typedef {import('libp2p-interfaces/src/connection').Connection} Connection
  * @typedef {import('./')} Dialer
  * @typedef {import('multiaddr')} Multiaddr
  */
@@ -45,7 +43,7 @@ class DialRequest {
    * @async
    * @param {object} [options]
    * @param {AbortSignal} [options.signal] - An AbortController signal
-   * @returns {Connection}
+   * @returns {Promise<Connection>}
    */
   async run (options) {
     const tokens = this.dialer.getTokens(this.addrs.length)
diff --git a/src/dialer/index.js b/src/dialer/index.js
index 18be09c1a5..4233e2d977 100644
--- a/src/dialer/index.js
+++ b/src/dialer/index.js
@@ -1,12 +1,13 @@
 'use strict'
 
-const multiaddr = require('multiaddr')
+const debug = require('debug')
+const log = Object.assign(debug('libp2p:dialer'), {
+  error: debug('libp2p:dialer:err')
+})
 const errCode = require('err-code')
+const multiaddr = require('multiaddr')
 const TimeoutController = require('timeout-abort-controller')
 const anySignal = require('any-signal')
-const debug = require('debug')
-const log = debug('libp2p:dialer')
-log.error = debug('libp2p:dialer:error')
 
 const { DialRequest } = require('./dial-request')
 const { publicAddressesFirst } = require('libp2p-utils/src/address-sort')
@@ -20,9 +21,11 @@ const {
 } = require('../constants')
 
 /**
+ * @typedef {import('libp2p-interfaces/src/connection').Connection} Connection
  * @typedef {import('multiaddr')} Multiaddr
  * @typedef {import('peer-id')} PeerId
  * @typedef {import('../peer-store')} PeerStore
+ * @typedef {import('../peer-store/address-book').Address} Address
  * @typedef {import('../transport-manager')} TransportManager
  * @typedef {import('./dial-request')} DialRequest
  */
@@ -172,7 +175,7 @@ class Dialer {
    * @param {AbortSignal} [options.signal] - An AbortController signal
    * @returns {PendingDial}
    */
-  _createPendingDial (dialTarget, options) {
+  _createPendingDial (dialTarget, options = {}) {
     const dialAction = (addr, options) => {
       if (options.signal.aborted) throw errCode(new Error('already aborted'), codes.ERR_ALREADY_ABORTED)
       return this.transportManager.dial(addr, options)
diff --git a/src/get-peer.js b/src/get-peer.js
index 29422334eb..35e2f26429 100644
--- a/src/get-peer.js
+++ b/src/get-peer.js
@@ -7,7 +7,6 @@ const errCode = require('err-code')
 const { codes } = require('./errors')
 
 /**
- * @typedef {import('peer-id')} PeerId
  * @typedef {import('multiaddr')} Multiaddr
  */
 
@@ -16,7 +15,7 @@ const { codes } = require('./errors')
  * If a multiaddr is received, the addressBook is updated.
  *
  * @param {PeerId|multiaddr|string} peer
- * @returns {{ id: PeerId, multiaddrs: Multiaddr[] }}
+ * @returns {{ id: PeerId, multiaddrs: Multiaddr[]|undefined }}
  */
 function getPeer (peer) {
   if (typeof peer === 'string') {
diff --git a/src/identify/index.js b/src/identify/index.js
index 7b1617e139..fe8b91b0a4 100644
--- a/src/identify/index.js
+++ b/src/identify/index.js
@@ -1,13 +1,13 @@
 'use strict'
 
 const debug = require('debug')
-const log = debug('libp2p:identify')
-log.error = debug('libp2p:identify:error')
-
+const log = Object.assign(debug('libp2p:identify'), {
+  error: debug('libp2p:identify:err')
+})
 const errCode = require('err-code')
 const pb = require('it-protocol-buffers')
 const lp = require('it-length-prefixed')
-const pipe = require('it-pipe')
+const { pipe } = require('it-pipe')
 const { collect, take, consume } = require('streaming-iterables')
 const uint8ArrayFromString = require('uint8arrays/from-string')
 
@@ -50,9 +50,7 @@ class IdentifyService {
 
     // When a new connection happens, trigger identify
     this.connectionManager.on('peer:connect', (connection) => {
-      const peerId = connection.remotePeer
-
-      this.identify(connection, peerId).catch(log.error)
+      this.identify(connection).catch(log.error)
     })
 
     // When self multiaddrs change, trigger identify-push
@@ -74,7 +72,7 @@ class IdentifyService {
    * Send an Identify Push update to the list of connections
    *
    * @param {Connection[]} connections
-   * @returns {Promise<void>}
+   * @returns {Promise<void[]>}
    */
   async push (connections) {
     const signedPeerRecord = await this.peerStore.addressBook.getRawEnvelope(this.peerId)
@@ -205,7 +203,7 @@ class IdentifyService {
    * @param {string} options.protocol
    * @param {DuplexIterableStream} options.stream
    * @param {Connection} options.connection
-   * @returns {Promise<void>}
+   * @returns {Promise<void>|undefined}
    */
   handleMessage ({ connection, stream, protocol }) {
     switch (protocol) {
@@ -226,6 +224,7 @@ class IdentifyService {
    * @param {Object} options
    * @param {DuplexIterableStream} options.stream
    * @param {Connection} options.connection
+   * @returns {Promise<void>}
    */
   async _handleIdentify ({ connection, stream }) {
     let publicKey = new Uint8Array(0)
@@ -265,6 +264,7 @@ class IdentifyService {
    * @param {object} options
    * @param {DuplexIterableStream} options.stream
    * @param {Connection} options.connection
+   * @returns {Promise<void>}
    */
   async _handlePush ({ connection, stream }) {
     let message
diff --git a/src/index.js b/src/index.js
index eca2206fa8..d9440adf1e 100644
--- a/src/index.js
+++ b/src/index.js
@@ -1,10 +1,11 @@
 'use strict'
 
-const { EventEmitter } = require('events')
 const debug = require('debug')
+const log = Object.assign(debug('libp2p'), {
+  error: debug('libp2p:err')
+})
+const { EventEmitter } = require('events')
 const globalThis = require('ipfs-utils/src/globalthis')
-const log = debug('libp2p')
-log.error = debug('libp2p:error')
 
 const errCode = require('err-code')
 const PeerId = require('peer-id')
@@ -36,6 +37,7 @@ const {
 
 /**
  * @typedef {import('multiaddr')} Multiaddr
+ * @typedef {import('libp2p-interfaces/src/connection').Connection} Connection
  */
 
 /**
@@ -131,6 +133,7 @@ class Libp2p extends EventEmitter {
 
       const keychainOpts = Keychain.generateOptions()
 
+      /** @type {Keychain} */
       this.keychain = new Keychain(this._options.keychain.datastore, {
         passPhrase: this._options.keychain.pass,
         ...keychainOpts,
@@ -285,7 +288,7 @@ class Libp2p extends EventEmitter {
    * Stop the libp2p node by closing its listeners and open connections
    *
    * @async
-   * @returns {void}
+   * @returns {Promise<void>}
    */
   async stop () {
     log('libp2p is stopping')
@@ -331,7 +334,7 @@ class Libp2p extends EventEmitter {
    * Imports the private key as 'self', if needed.
    *
    * @async
-   * @returns {void}
+   * @returns {Promise<void>}
    */
   async loadKeychain () {
     try {
@@ -360,12 +363,12 @@ class Libp2p extends EventEmitter {
    * peer will be added to the nodes `peerStore`
    *
    * @param {PeerId|Multiaddr|string} peer - The peer to dial
-   * @param {object} options
+   * @param {object} [options]
    * @param {AbortSignal} [options.signal]
    * @returns {Promise<Connection>}
    */
   dial (peer, options) {
-    return this.dialProtocol(peer, null, options)
+    return this.dialProtocol(peer, undefined, options)
   }
 
   /**
@@ -375,8 +378,8 @@ class Libp2p extends EventEmitter {
    *
    * @async
    * @param {PeerId|Multiaddr|string} peer - The peer to dial
-   * @param {string[]|string} protocols
-   * @param {object} options
+   * @param {undefined|string[]|string} protocols
+   * @param {object} [options]
    * @param {AbortSignal} [options.signal]
    * @returns {Promise<Connection|*>}
    */
@@ -644,10 +647,10 @@ class Libp2p extends EventEmitter {
  * Like `new Libp2p(options)` except it will create a `PeerId`
  * instance if one is not provided in options.
  *
- * @param {Libp2pOptions & CreateOptions} [options] - Libp2p configuration options
- * @returns {Libp2p}
+ * @param {Libp2pOptions & CreateOptions} options - Libp2p configuration options
+ * @returns {Promise<Libp2p>}
  */
-Libp2p.create = async function create (options = {}) {
+Libp2p.create = async function create (options) {
   if (options.peerId) {
     return new Libp2p(options)
   }
diff --git a/src/insecure/plaintext.js b/src/insecure/plaintext.js
index 0e9f8dd992..92010798c1 100644
--- a/src/insecure/plaintext.js
+++ b/src/insecure/plaintext.js
@@ -1,11 +1,12 @@
 'use strict'
 
+const debug = require('debug')
+const log = Object.assign(debug('libp2p:plaintext'), {
+  error: debug('libp2p:plaintext:err')
+})
 const handshake = require('it-handshake')
 const lp = require('it-length-prefixed')
 const PeerId = require('peer-id')
-const debug = require('debug')
-const log = debug('libp2p:plaintext')
-log.error = debug('libp2p:plaintext:error')
 const { UnexpectedPeerError, InvalidCryptoExchangeError } = require('libp2p-interfaces/src/crypto/errors')
 
 const { Exchange, KeyType } = require('./proto')
diff --git a/src/keychain/index.js b/src/keychain/index.js
index c823eb3e46..10d402c669 100644
--- a/src/keychain/index.js
+++ b/src/keychain/index.js
@@ -101,7 +101,8 @@ class Keychain {
    * Creates a new instance of a key chain.
    *
    * @param {DS} store - where the key are.
-   * @param {object} options - ???
+   * @param {object} options
+   * @class
    */
   constructor (store, options) {
     if (!store) {
diff --git a/src/peer-routing.js b/src/peer-routing.js
index 841a3279c3..88a230196c 100644
--- a/src/peer-routing.js
+++ b/src/peer-routing.js
@@ -1,9 +1,10 @@
 'use strict'
 
-const errCode = require('err-code')
 const debug = require('debug')
-const log = debug('libp2p:peer-routing')
-log.error = debug('libp2p:peer-routing:error')
+const log = Object.assign(debug('libp2p:peer-routing'), {
+  error: debug('libp2p:peer-routing:err')
+})
+const errCode = require('err-code')
 
 const all = require('it-all')
 const pAny = require('p-any')
@@ -69,7 +70,6 @@ class PeerRouting {
     clearDelayedInterval(this._timeoutId)
   }
 
-<<<<<<< HEAD
   /**
    * Iterates over all peer routers in series to find the given peer.
    *
@@ -89,20 +89,6 @@ class PeerRouting {
       // If we don't have a result, we need to provide an error to keep trying
       if (!result || Object.keys(result).length === 0) {
         throw errCode(new Error('not found'), 'NOT_FOUND')
-=======
-  return {
-    /**
-     * Iterates over all peer routers in series to find the given peer.
-     *
-     * @param {string} id - The id of the peer to find
-     * @param {object} [options]
-     * @param {number} [options.timeout] - How long the query should run
-     * @returns {Promise<{ id: PeerId, multiaddrs: Multiaddr[] }>}
-     */
-    findPeer: async (id, options) => { // eslint-disable-line require-await
-      if (!routers.length) {
-        throw errCode(new Error('No peer routers available'), 'NO_ROUTERS_AVAILABLE')
->>>>>>> chore: address review
       }
 
       return result
diff --git a/src/peer-store/address-book.js b/src/peer-store/address-book.js
index bbfc30c8b9..5545997322 100644
--- a/src/peer-store/address-book.js
+++ b/src/peer-store/address-book.js
@@ -1,9 +1,10 @@
 'use strict'
 
-const errcode = require('err-code')
 const debug = require('debug')
-const log = debug('libp2p:peer-store:address-book')
-log.error = debug('libp2p:peer-store:address-book:error')
+const log = Object.assign(debug('libp2p:peer-store:address-book'), {
+  error: debug('libp2p:peer-store:address-book:err')
+})
+const errcode = require('err-code')
 
 const multiaddr = require('multiaddr')
 const PeerId = require('peer-id')
@@ -18,6 +19,7 @@ const Envelope = require('../record/envelope')
 
 /**
  * @typedef {import('multiaddr')} Multiaddr
+ * @typedef {import('./')} PeerStore
  */
 
 /**
@@ -75,7 +77,7 @@ class AddressBook extends Book {
     /**
      * Map known peers to their known Address Entries.
      *
-     * @type {Map<string, Entry[]>}
+     * @type {Map<string, Entry>}
      */
     this.data = new Map()
   }
@@ -110,7 +112,7 @@ class AddressBook extends Book {
 
     const peerId = peerRecord.peerId
     const id = peerId.toB58String()
-    const entry = this.data.get(id) || {}
+    const entry = this.data.get(id) || { record: undefined }
     const storedRecord = entry.record
 
     // ensure seq is greater than, or equal to, the last received
@@ -156,7 +158,7 @@ class AddressBook extends Book {
    * Returns undefined if no record exists.
    *
    * @param {PeerId} peerId
-   * @returns {Promise<Envelope|void>}
+   * @returns {Promise<Envelope|void>|undefined}
    */
   getPeerRecord (peerId) {
     const raw = this.getRawEnvelope(peerId)
diff --git a/src/peer-store/book.js b/src/peer-store/book.js
index cbfafdd6b9..447483d9e2 100644
--- a/src/peer-store/book.js
+++ b/src/peer-store/book.js
@@ -9,12 +9,17 @@ const {
 
 const passthrough = data => data
 
+/**
+ * @typedef {import('./')} PeerStore
+ */
+
+/**
+ * @template T
+ */
 class Book {
   /**
    * The Book is the skeleton for the PeerStore books.
    *
-   * @template T
-   *
    * @class
    * @param {Object} properties
    * @param {PeerStore} properties.peerStore - PeerStore instance.
@@ -31,7 +36,7 @@ class Book {
     /**
      * Map known peers to their data.
      *
-     * @type {Map<string, T[]}
+     * @type {Map<string, T[]|T>}
      */
     this.data = new Map()
   }
@@ -94,6 +99,7 @@ class Book {
 
     const rec = this.data.get(peerId.toB58String())
 
+    // @ts-ignore
     return rec ? [...rec] : undefined
   }
 
diff --git a/src/peer-store/index.js b/src/peer-store/index.js
index 3713d7d4d0..07762b8cbc 100644
--- a/src/peer-store/index.js
+++ b/src/peer-store/index.js
@@ -1,9 +1,6 @@
 'use strict'
 
 const errcode = require('err-code')
-const debug = require('debug')
-const log = debug('libp2p:peer-store')
-log.error = debug('libp2p:peer-store:error')
 
 const { EventEmitter } = require('events')
 const PeerId = require('peer-id')
@@ -14,7 +11,7 @@ const MetadataBook = require('./metadata-book')
 const ProtoBook = require('./proto-book')
 
 const {
-  ERR_INVALID_PARAMETERS
+  codes: { ERR_INVALID_PARAMETERS }
 } = require('../errors')
 
 /**
@@ -127,7 +124,7 @@ class PeerStore extends EventEmitter {
    * Get the stored information of a given peer.
    *
    * @param {PeerId} peerId
-   * @returns {Peer}
+   * @returns {Peer|undefined}
    */
   get (peerId) {
     if (!PeerId.isPeerId(peerId)) {
diff --git a/src/peer-store/key-book.js b/src/peer-store/key-book.js
index 6a045ad58f..1c22db63ef 100644
--- a/src/peer-store/key-book.js
+++ b/src/peer-store/key-book.js
@@ -1,9 +1,10 @@
 'use strict'
 
-const errcode = require('err-code')
 const debug = require('debug')
-const log = debug('libp2p:peer-store:key-book')
-log.error = debug('libp2p:peer-store:key-book:error')
+const log = Object.assign(debug('libp2p:peer-store:key-book'), {
+  error: debug('libp2p:peer-store:key-book:err')
+})
+const errcode = require('err-code')
 
 const PeerId = require('peer-id')
 
@@ -13,6 +14,10 @@ const {
   codes: { ERR_INVALID_PARAMETERS }
 } = require('../errors')
 
+/**
+ * @typedef {import('./')} PeerStore
+ */
+
 /**
  * @extends {Book}
  */
diff --git a/src/peer-store/metadata-book.js b/src/peer-store/metadata-book.js
index 796c9ee8f9..7d24312cf8 100644
--- a/src/peer-store/metadata-book.js
+++ b/src/peer-store/metadata-book.js
@@ -1,9 +1,10 @@
 'use strict'
 
-const errcode = require('err-code')
 const debug = require('debug')
-const log = debug('libp2p:peer-store:proto-book')
-log.error = debug('libp2p:peer-store:proto-book:error')
+const log = Object.assign(debug('libp2p:peer-store:proto-book'), {
+  error: debug('libp2p:peer-store:proto-book:err')
+})
+const errcode = require('err-code')
 const uint8ArrayEquals = require('uint8arrays/equals')
 
 const PeerId = require('peer-id')
@@ -14,6 +15,10 @@ const {
   codes: { ERR_INVALID_PARAMETERS }
 } = require('../errors')
 
+/**
+ * @typedef {import('./')} PeerStore
+ */
+
 /**
  * @extends {Book}
  *
diff --git a/src/peer-store/persistent/index.js b/src/peer-store/persistent/index.js
index f23c23e193..ceb77a650c 100644
--- a/src/peer-store/persistent/index.js
+++ b/src/peer-store/persistent/index.js
@@ -1,9 +1,9 @@
 'use strict'
 
 const debug = require('debug')
-const log = debug('libp2p:persistent-peer-store')
-log.error = debug('libp2p:persistent-peer-store:error')
-
+const log = Object.assign(debug('libp2p:persistent-peer-store'), {
+  error: debug('libp2p:persistent-peer-store:err')
+})
 const { Key } = require('interface-datastore')
 const multiaddr = require('multiaddr')
 const PeerId = require('peer-id')
@@ -346,6 +346,7 @@ class PersistentPeerStore extends PeerStore {
         case 'addrs':
           decoded = Addresses.decode(value)
 
+          // @ts-ignore
           this.addressBook._setData(
             peerId,
             {
@@ -363,6 +364,7 @@ class PersistentPeerStore extends PeerStore {
         case 'keys':
           decoded = await PeerId.createFromPubKey(value)
 
+          // @ts-ignore
           this.keyBook._setData(
             decoded,
             decoded,
@@ -378,6 +380,7 @@ class PersistentPeerStore extends PeerStore {
         case 'protos':
           decoded = Protocols.decode(value)
 
+          // @ts-ignore
           this.protoBook._setData(
             peerId,
             new Set(decoded.protocols),
diff --git a/src/peer-store/proto-book.js b/src/peer-store/proto-book.js
index 60b9c503f9..18529d7369 100644
--- a/src/peer-store/proto-book.js
+++ b/src/peer-store/proto-book.js
@@ -1,10 +1,10 @@
 'use strict'
 
-const errcode = require('err-code')
 const debug = require('debug')
-const log = debug('libp2p:peer-store:proto-book')
-log.error = debug('libp2p:peer-store:proto-book:error')
-
+const log = Object.assign(debug('libp2p:peer-store:proto-book'), {
+  error: debug('libp2p:peer-store:proto-book:err')
+})
+const errcode = require('err-code')
 const PeerId = require('peer-id')
 
 const Book = require('./book')
@@ -13,6 +13,10 @@ const {
   codes: { ERR_INVALID_PARAMETERS }
 } = require('../errors')
 
+/**
+ * @typedef {import('./')} PeerStore
+ */
+
 /**
  * @extends {Book}
  *
@@ -79,6 +83,7 @@ class ProtoBook extends Book {
       return this
     }
 
+    // @ts-ignore
     this._setData(peerId, newSet)
     log(`stored provided protocols for ${id}`)
 
@@ -114,6 +119,7 @@ class ProtoBook extends Book {
       return this
     }
 
+    // @ts-ignore
     this._setData(peerId, newSet)
     log(`added provided protocols for ${id}`)
 
@@ -152,6 +158,7 @@ class ProtoBook extends Book {
         return this
       }
 
+      // @ts-ignore
       this._setData(peerId, newSet)
       log(`removed provided protocols for ${id}`)
     }
diff --git a/src/ping/index.js b/src/ping/index.js
index 5ad54021cf..a242f9fb1a 100644
--- a/src/ping/index.js
+++ b/src/ping/index.js
@@ -1,14 +1,16 @@
 'use strict'
 
 const debug = require('debug')
-const log = debug('libp2p-ping')
-log.error = debug('libp2p-ping:error')
+const log = Object.assign(debug('libp2p:ping'), {
+  error: debug('libp2p:ping:err')
+})
 const errCode = require('err-code')
 
 const crypto = require('libp2p-crypto')
-const pipe = require('it-pipe')
+const { pipe } = require('it-pipe')
 const { toBuffer } = require('it-buffer')
 const { collect, take } = require('streaming-iterables')
+const equals = require('uint8arrays/equals')
 
 const { PROTOCOL, PING_LENGTH } = require('./constants')
 
@@ -26,11 +28,12 @@ const { PROTOCOL, PING_LENGTH } = require('./constants')
  * @returns {Promise<number>}
  */
 async function ping (node, peer) {
+  // @ts-ignore
   log('dialing %s to %s', PROTOCOL, peer.toB58String ? peer.toB58String() : peer)
 
   const { stream } = await node.dialProtocol(peer, PROTOCOL)
 
-  const start = new Date()
+  const start = new Date().getTime()
   const data = crypto.randomBytes(PING_LENGTH)
 
   const [result] = await pipe(
@@ -42,7 +45,7 @@ async function ping (node, peer) {
   )
   const end = Date.now()
 
-  if (!data.equals(result)) {
+  if (!equals(data, result)) {
     throw errCode(new Error('Received wrong ping ack'), 'ERR_WRONG_PING_ACK')
   }
 
diff --git a/src/pnet/crypto.js b/src/pnet/crypto.js
index ae824bfcfb..9cfcbc8e6f 100644
--- a/src/pnet/crypto.js
+++ b/src/pnet/crypto.js
@@ -1,16 +1,17 @@
 'use strict'
 
 const debug = require('debug')
+const log = Object.assign(debug('libp2p:pnet'), {
+  trace: debug('libp2p:pnet:trace'),
+  error: debug('libp2p:pnet:err')
+})
+
 const Errors = require('./errors')
 const xsalsa20 = require('xsalsa20')
 const KEY_LENGTH = require('./key-generator').KEY_LENGTH
 const uint8ArrayFromString = require('uint8arrays/from-string')
 const uint8ArrayToString = require('uint8arrays/to-string')
 
-const log = debug('libp2p:pnet')
-log.trace = debug('libp2p:pnet:trace')
-log.error = debug('libp2p:pnet:err')
-
 /**
  * Creates a stream iterable to encrypt messages in a private network
  *
diff --git a/src/pnet/index.js b/src/pnet/index.js
index d2b97b2cb7..74c99947e0 100644
--- a/src/pnet/index.js
+++ b/src/pnet/index.js
@@ -1,12 +1,16 @@
 'use strict'
 
-const pipe = require('it-pipe')
+const debug = require('debug')
+const log = Object.assign(debug('libp2p:pnet'), {
+  error: debug('libp2p:pnet:err')
+})
+const { pipe } = require('it-pipe')
 const errcode = require('err-code')
 const duplexPair = require('it-pair/duplex')
 const crypto = require('libp2p-crypto')
 const Errors = require('./errors')
 const {
-  ERR_INVALID_PARAMETERS
+  codes: { ERR_INVALID_PARAMETERS }
 } = require('../errors')
 const {
   createBoxStream,
@@ -15,9 +19,6 @@ const {
 } = require('./crypto')
 const handshake = require('it-handshake')
 const { NONCE_LENGTH } = require('./key-generator')
-const debug = require('debug')
-const log = debug('libp2p:pnet')
-log.error = debug('libp2p:pnet:err')
 
 /**
  * @typedef {import('libp2p-interfaces/src/connection').Connection} Connection
@@ -44,7 +45,7 @@ class Protector {
    * created with.
    *
    * @param {Connection} connection - The connection to protect
-   * @returns {DuplexIterableStream} A protected duplex iterable
+   * @returns {Promise<DuplexIterableStream>} A protected duplex iterable
    */
   async protect (connection) {
     if (!connection) {
diff --git a/src/pnet/key-generator.js b/src/pnet/key-generator.js
index b3676dcccf..d88f23d83c 100644
--- a/src/pnet/key-generator.js
+++ b/src/pnet/key-generator.js
@@ -22,6 +22,8 @@ module.exports = generate
 module.exports.NONCE_LENGTH = 24
 module.exports.KEY_LENGTH = KEY_LENGTH
 
+// @ts-ignore
 if (require.main === module) {
+  // @ts-ignore
   generate(process.stdout)
 }
diff --git a/src/pubsub-adapter.js b/src/pubsub-adapter.js
index 4f2134fe6c..4c8aed8f2a 100644
--- a/src/pubsub-adapter.js
+++ b/src/pubsub-adapter.js
@@ -2,6 +2,7 @@
 
 /**
  * @typedef {import('libp2p-interfaces/src/pubsub').InMessage} InMessage
+ * @typedef {import('libp2p-interfaces/src/pubsub')} PubsubRouter
  */
 
 // Pubsub adapter to keep API with handlers while not removed.
@@ -12,7 +13,7 @@ module.exports = (PubsubRouter, libp2p, options) => {
      *
      * @override
      * @param {string} topic
-     * @param {function(msg: InMessage)} [handler]
+     * @param {(msg: InMessage) => void} [handler]
      * @returns {void}
      */
     subscribe (topic, handler) {
@@ -26,7 +27,7 @@ module.exports = (PubsubRouter, libp2p, options) => {
      *
      * @override
      * @param {string} topic
-     * @param {function(msg: InMessage)} [handler]
+     * @param {(msg: InMessage) => void} [handler]
      * @returns {void}
      */
     unsubscribe (topic, handler) {
diff --git a/src/record/envelope/index.js b/src/record/envelope/index.js
index cee2e26b96..88a702afc5 100644
--- a/src/record/envelope/index.js
+++ b/src/record/envelope/index.js
@@ -1,8 +1,5 @@
 'use strict'
 
-const debug = require('debug')
-const log = debug('libp2p:envelope')
-log.error = debug('libp2p:envelope:error')
 const errCode = require('err-code')
 const uint8arraysConcat = require('uint8arrays/concat')
 const uint8arraysFromString = require('uint8arrays/from-string')
@@ -15,7 +12,7 @@ const { codes } = require('../../errors')
 const Protobuf = require('./envelope.proto')
 
 /**
- * @typedef {import('peer-id')} PeerId
+ * @typedef {import('libp2p-interfaces/src/record')} Record
  */
 
 class Envelope {
@@ -145,7 +142,7 @@ Envelope.createFromProtobuf = async (data) => {
  * @async
  * @param {Record} record
  * @param {PeerId} peerId
- * @returns {Envelope}
+ * @returns {Promise<Envelope>}
  */
 Envelope.seal = async (record, peerId) => {
   const domain = record.domain
@@ -169,7 +166,7 @@ Envelope.seal = async (record, peerId) => {
  *
  * @param {Uint8Array} data
  * @param {string} domain
- * @returns {Envelope}
+ * @returns {Promise<Envelope>}
  */
 Envelope.openAndCertify = async (data, domain) => {
   const envelope = await Envelope.createFromProtobuf(data)
diff --git a/src/registrar.js b/src/registrar.js
index 4917aeb5b8..70998c5d1c 100644
--- a/src/registrar.js
+++ b/src/registrar.js
@@ -1,12 +1,13 @@
 'use strict'
 
 const debug = require('debug')
+const log = Object.assign(debug('libp2p:peer-store'), {
+  error: debug('libp2p:peer-store:err')
+})
 const errcode = require('err-code')
-const log = debug('libp2p:peer-store')
-log.error = debug('libp2p:peer-store:error')
 
 const {
-  ERR_INVALID_PARAMETERS
+  codes: { ERR_INVALID_PARAMETERS }
 } = require('./errors')
 const Topology = require('libp2p-interfaces/src/topology')
 
@@ -73,11 +74,12 @@ class Registrar {
    */
   register (topology) {
     if (!Topology.isTopology(topology)) {
+      log.error('topology must be an instance of interfaces/topology')
       throw errcode(new Error('topology must be an instance of interfaces/topology'), ERR_INVALID_PARAMETERS)
     }
 
     // Create topology
-    const id = (parseInt(Math.random() * 1e9)).toString(36) + Date.now()
+    const id = (Math.random() * 1e9).toString(36) + Date.now()
 
     this.topologies.set(id, topology)
 
diff --git a/src/transport-manager.js b/src/transport-manager.js
index 06ab69b74b..d9aef5335c 100644
--- a/src/transport-manager.js
+++ b/src/transport-manager.js
@@ -1,11 +1,13 @@
 'use strict'
 
+const debug = require('debug')
+const log = Object.assign(debug('libp2p:transports'), {
+  error: debug('libp2p:transports:err')
+})
+
 const pSettle = require('p-settle')
 const { codes } = require('./errors')
 const errCode = require('err-code')
-const debug = require('debug')
-const log = debug('libp2p:transports')
-log.error = debug('libp2p:transports:error')
 
 const { updateSelfPeerRecord } = require('./record/utils')
 
@@ -18,7 +20,7 @@ const { updateSelfPeerRecord } = require('./record/utils')
  * @property {import('./upgrader')} upgrader
  *
  * @typedef {Object} TransportManagerOptions
- * @property {boolean} [faultTolerance = FAULT_TOLERANCE.FATAL_ALL] - Address listen error tolerance.
+ * @property {number} [faultTolerance = FAULT_TOLERANCE.FATAL_ALL] - Address listen error tolerance.
  */
 
 class TransportManager {
@@ -126,7 +128,7 @@ class TransportManager {
   /**
    * Returns all the transports instances.
    *
-   * @returns {Iterator<Transport>}
+   * @returns {IterableIterator<Transport>}
    */
   getTransports () {
     return this._transports.values()
@@ -166,7 +168,7 @@ class TransportManager {
       // For each supported multiaddr, create a listener
       for (const addr of supportedAddrs) {
         log('creating listener for %s on %s', key, addr)
-        const listener = transport.createListener({}, this.onConnection)
+        const listener = transport.createListener({})
         this._listeners.get(key).push(listener)
 
         // Track listen/close events
diff --git a/src/types.ts b/src/types.ts
new file mode 100644
index 0000000000..7f0ad3680c
--- /dev/null
+++ b/src/types.ts
@@ -0,0 +1,18 @@
+
+// Insecure Message types
+export enum KeyType {
+  RSA = 0,
+  Ed25519 = 1,
+  Secp256k1 = 2,
+  ECDSA = 3
+}
+
+export type MessagePublicKey = {
+  Type: KeyType
+  Data: Uint8Array
+}
+
+export type MessageExchange = {
+  id: Uint8Array
+  pubKey: MessagePublicKey
+}
diff --git a/src/upgrader.js b/src/upgrader.js
index 0a422b2e82..ca798deaa7 100644
--- a/src/upgrader.js
+++ b/src/upgrader.js
@@ -1,20 +1,22 @@
 'use strict'
 
 const debug = require('debug')
-const log = debug('libp2p:upgrader')
-log.error = debug('libp2p:upgrader:error')
+const log = Object.assign(debug('libp2p:upgrader'), {
+  error: debug('libp2p:upgrader:err')
+})
+const errCode = require('err-code')
 const Multistream = require('multistream-select')
 const { Connection } = require('libp2p-interfaces/src/connection')
 const ConnectionStatus = require('libp2p-interfaces/src/connection/status')
 const PeerId = require('peer-id')
 const pipe = require('it-pipe')
-const errCode = require('err-code')
 const mutableProxy = require('mutable-proxy')
 
 const { codes } = require('./errors')
 
 /**
  * @typedef {import('libp2p-interfaces/src/connection').Connection} Connection
+ * @typedef {import('multiaddr')} Multiaddr
  */
 
 /**
@@ -36,11 +38,11 @@ class Upgrader {
   /**
    * @param {object} options
    * @param {PeerId} options.localPeer
-   * @param {Metrics} options.metrics
+   * @param {import('./metrics')} [options.metrics]
    * @param {Map<string, Crypto>} options.cryptos
    * @param {Map<string, Muxer>} options.muxers
-   * @param {function(Connection)} options.onConnection - Called when a connection is upgraded
-   * @param {function(Connection)} options.onConnectionEnd
+   * @param {(Connection) => void} options.onConnection - Called when a connection is upgraded
+   * @param {(Connection) => void} options.onConnectionEnd
    */
   constructor ({
     localPeer,
@@ -78,7 +80,7 @@ class Upgrader {
 
     if (this.metrics) {
       ({ setTarget: setPeer, proxy: proxyPeer } = mutableProxy())
-      const idString = (parseInt(Math.random() * 1e9)).toString(36) + Date.now()
+      const idString = (Math.random() * 1e9).toString(36) + Date.now()
       setPeer({ toB58String: () => idString })
       maConn = this.metrics.trackStream({ stream: maConn, remotePeer: proxyPeer })
     }
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 0000000000..5b9a618c43
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,9 @@
+{
+  "extends": "./node_modules/aegir/src/config/tsconfig.aegir.json",
+  "compilerOptions": {
+    "outDir": "dist"
+  },
+  "include": [
+    "src"
+  ]
+}
\ No newline at end of file