diff --git a/package.json b/package.json
index 79f291f..adbfaf8 100644
--- a/package.json
+++ b/package.json
@@ -45,22 +45,22 @@
     "istanbul": "^0.4.3",
     "libp2p-multiplex": "^0.2.1",
     "libp2p-spdy": "^0.3.1",
-    "libp2p-tcp": "^0.5.0",
-    "libp2p-websockets": "^0.4.1",
-    "multiaddr": "^1.4.0",
-    "peer-id": "^0.6.6",
-    "peer-info": "^0.6.2",
+    "libp2p-tcp": "^0.5.1",
+    "libp2p-websockets": "^0.4.3",
     "pre-commit": "^1.1.2",
     "stream-pair": "^1.0.3"
   },
   "dependencies": {
-    "async": "^2.0.0-rc.4",
     "babel-runtime": "^6.6.1",
     "duplex-passthrough": "github:diasdavid/duplex-passthrough",
     "ip-address": "^5.8.0",
     "lodash.contains": "^2.4.3",
+    "multiaddr": "^1.4.0",
     "multistream-select": "^0.6.5",
-    "protocol-buffers-stream": "^1.3.1"
+    "peer-id": "^0.6.6",
+    "peer-info": "^0.6.2",
+    "protocol-buffers-stream": "^1.3.1",
+    "run-parallel": "^1.1.6"
   },
   "aegir": {
     "webpack": {
@@ -79,4 +79,4 @@
     "Pau Ramon Revilla <masylum@gmail.com>",
     "Richard Littauer <richard.littauer@gmail.com>"
   ]
-}
\ No newline at end of file
+}
diff --git a/src/index.js b/src/index.js
index 676575d..0f0bb3d 100644
--- a/src/index.js
+++ b/src/index.js
@@ -1,12 +1,12 @@
 'use strict'
 
-const async = require('async')
 const multistream = require('multistream-select')
 const identify = require('./identify')
 const DuplexPassThrough = require('duplex-passthrough')
 const contains = require('lodash.contains')
 const util = require('util')
 const EE = require('events').EventEmitter
+const parallel = require('run-parallel')
 
 exports = module.exports = Swarm
 
@@ -118,7 +118,13 @@ function Swarm (peerInfo) {
   }
 
   this.transport.close = (key, callback) => {
-    this.transports[key].close(callback)
+    const transport = this.transports[key]
+
+    if (!transport) {
+      return callback(new Error(`Trying to close non existing transport: ${key}`))
+    }
+
+    transport.close(callback)
   }
 
   // connections --
@@ -372,14 +378,9 @@ function Swarm (peerInfo) {
       this.muxedConns[key].muxer.end()
     })
 
-    async.each(
-      Object.keys(this.transports),
-      (key, cb) => this.transports[key].close(cb),
-      () => {
-        // Ignoring close errors
-        callback()
-      }
-    )
+    parallel(Object.keys(this.transports).map((key) => {
+      return (cb) => this.transports[key].close(cb)
+    }), callback)
   }
 }
 
diff --git a/test/01-transport-tcp.node.js b/test/01-transport-tcp.node.js
index 3358210..2b18105 100644
--- a/test/01-transport-tcp.node.js
+++ b/test/01-transport-tcp.node.js
@@ -3,6 +3,7 @@
 
 const expect = require('chai').expect
 
+const parallel = require('run-parallel')
 const multiaddr = require('multiaddr')
 const Peer = require('peer-info')
 const Swarm = require('../src')
@@ -92,15 +93,10 @@ describe('transport - tcp', function () {
   })
 
   it('close', (done) => {
-    var count = 0
-    swarmA.transport.close('tcp', closed)
-    swarmB.transport.close('tcp', closed)
-
-    function closed () {
-      if (++count === 2) {
-        done()
-      }
-    }
+    parallel([
+      (cb) => swarmA.transport.close('tcp', cb),
+      (cb) => swarmB.transport.close('tcp', cb)
+    ], done)
   })
 
   it('support port 0', (done) => {
diff --git a/test/03-transport-websockets.node.js b/test/03-transport-websockets.node.js
index 926f4c7..a1a06e1 100644
--- a/test/03-transport-websockets.node.js
+++ b/test/03-transport-websockets.node.js
@@ -3,6 +3,7 @@
 
 const expect = require('chai').expect
 
+const parallel = require('run-parallel')
 const multiaddr = require('multiaddr')
 const Peer = require('peer-info')
 const Swarm = require('../src')
@@ -88,14 +89,9 @@ describe('transport - websockets', function () {
   })
 
   it('close', (done) => {
-    var count = 0
-    swarmA.transport.close('ws', closed)
-    swarmB.transport.close('ws', closed)
-
-    function closed () {
-      if (++count === 2) {
-        done()
-      }
-    }
+    parallel([
+      (cb) => swarmA.transport.close('ws', cb),
+      (cb) => swarmB.transport.close('ws', cb)
+    ], done)
   })
 })
diff --git a/test/04-muxing-multiplex.node.js b/test/04-muxing-multiplex.node.js
index d8a8507..0f0e18d 100644
--- a/test/04-muxing-multiplex.node.js
+++ b/test/04-muxing-multiplex.node.js
@@ -3,6 +3,7 @@
 
 const expect = require('chai').expect
 
+const parallel = require('run-parallel')
 const multiaddr = require('multiaddr')
 const Peer = require('peer-info')
 const Swarm = require('../src')
@@ -10,7 +11,7 @@ const TCP = require('libp2p-tcp')
 const multiplex = require('libp2p-spdy')
 
 describe('stream muxing with multiplex (on TCP)', function () {
-  this.timeout(20000)
+  this.timeout(60 * 1000)
 
   var swarmA
   var peerA
@@ -37,35 +38,22 @@ describe('stream muxing with multiplex (on TCP)', function () {
     swarmC = new Swarm(peerC)
 
     swarmA.transport.add('tcp', new TCP())
-    swarmA.transport.listen('tcp', {}, null, ready)
-
     swarmB.transport.add('tcp', new TCP())
-    swarmB.transport.listen('tcp', {}, null, ready)
-
     swarmC.transport.add('tcp', new TCP())
-    swarmC.transport.listen('tcp', {}, null, ready)
 
-    var counter = 0
-
-    function ready () {
-      if (++counter === 3) {
-        done()
-      }
-    }
+    parallel([
+      (cb) => swarmA.transport.listen('tcp', {}, null, cb),
+      (cb) => swarmB.transport.listen('tcp', {}, null, cb),
+      (cb) => swarmC.transport.listen('tcp', {}, null, cb)
+    ], done)
   })
 
   after((done) => {
-    var counter = 0
-
-    swarmA.close(closed)
-    swarmB.close(closed)
-    swarmC.close(closed)
-
-    function closed () {
-      if (++counter === 3) {
-        done()
-      }
-    }
+    parallel([
+      (cb) => swarmA.close(cb),
+      (cb) => swarmB.close(cb),
+      (cb) => swarmC.close(cb)
+    ], done)
   })
 
   it('add', (done) => {
diff --git a/test/05-muxing-spdy.node.js b/test/05-muxing-spdy.node.js
index a824dc2..9ed39a4 100644
--- a/test/05-muxing-spdy.node.js
+++ b/test/05-muxing-spdy.node.js
@@ -3,6 +3,7 @@
 
 const expect = require('chai').expect
 
+const parallel = require('run-parallel')
 const multiaddr = require('multiaddr')
 const Peer = require('peer-info')
 const Swarm = require('../src')
@@ -10,7 +11,7 @@ const TCP = require('libp2p-tcp')
 const spdy = require('libp2p-spdy')
 
 describe('stream muxing with spdy (on TCP)', function () {
-  this.timeout(20000)
+  this.timeout(60 * 1000)
 
   var swarmA
   var peerA
@@ -37,35 +38,22 @@ describe('stream muxing with spdy (on TCP)', function () {
     swarmC = new Swarm(peerC)
 
     swarmA.transport.add('tcp', new TCP())
-    swarmA.transport.listen('tcp', {}, null, ready)
-
     swarmB.transport.add('tcp', new TCP())
-    swarmB.transport.listen('tcp', {}, null, ready)
-
     swarmC.transport.add('tcp', new TCP())
-    swarmC.transport.listen('tcp', {}, null, ready)
 
-    var counter = 0
-
-    function ready () {
-      if (++counter === 3) {
-        done()
-      }
-    }
+    parallel([
+      (cb) => swarmA.transport.listen('tcp', {}, null, cb),
+      (cb) => swarmB.transport.listen('tcp', {}, null, cb),
+      (cb) => swarmC.transport.listen('tcp', {}, null, cb)
+    ], done)
   })
 
   after((done) => {
-    var counter = 0
-
-    swarmA.close(closed)
-    swarmB.close(closed)
-    // swarmC.close(closed)
-
-    function closed () {
-      if (++counter === 2) {
-        done()
-      }
-    }
+    parallel([
+      (cb) => swarmA.close(cb),
+      (cb) => swarmB.close(cb),
+      (cb) => swarmC.close(cb)
+    ], done)
   })
 
   it('add', (done) => {
@@ -130,7 +118,8 @@ describe('stream muxing with spdy (on TCP)', function () {
   })
 
   it('close one end, make sure the other does not blow', (done) => {
-    swarmC.close(() => {
+    swarmC.close((err) => {
+      if (err) throw err
       // to make sure it has time to propagate
       setTimeout(done, 1000)
     })
diff --git a/test/08-swarm-without-muxing.node.js b/test/08-swarm-without-muxing.node.js
index 39f4675..7463eb0 100644
--- a/test/08-swarm-without-muxing.node.js
+++ b/test/08-swarm-without-muxing.node.js
@@ -3,6 +3,7 @@
 
 const expect = require('chai').expect
 
+const parallel = require('run-parallel')
 const multiaddr = require('multiaddr')
 const Peer = require('peer-info')
 const Swarm = require('../src')
@@ -42,16 +43,10 @@ describe('high level API - 1st without stream multiplexing (on TCP)', function (
   })
 
   after((done) => {
-    var counter = 0
-
-    swarmA.close(closed)
-    swarmB.close(closed)
-
-    function closed () {
-      if (++counter === 2) {
-        done()
-      }
-    }
+    parallel([
+      (cb) => swarmA.close(cb),
+      (cb) => swarmB.close(cb)
+    ], done)
   })
 
   it('handle a protocol', (done) => {
diff --git a/test/09-swarm-with-muxing.node.js b/test/09-swarm-with-muxing.node.js
index 3c5a00f..f904ea8 100644
--- a/test/09-swarm-with-muxing.node.js
+++ b/test/09-swarm-with-muxing.node.js
@@ -3,6 +3,7 @@
 
 const expect = require('chai').expect
 
+const parallel = require('run-parallel')
 const multiaddr = require('multiaddr')
 const Peer = require('peer-info')
 const Swarm = require('../src')
@@ -45,19 +46,13 @@ describe('high level API - with everything mixed all together!', function () {
   })
 
   after((done) => {
-    var counter = 0
-
-    swarmA.close(closed)
-    swarmB.close(closed)
-    // swarmC.close(closed)
-    swarmD.close(closed)
-    swarmE.close(closed)
-
-    function closed () {
-      if (++counter === 4) {
-        done()
-      }
-    }
+    parallel([
+      (cb) => swarmA.close(cb),
+      (cb) => swarmB.close(cb),
+      // (cb) => swarmC.close(cb),
+      (cb) => swarmD.close(cb),
+      (cb) => swarmE.close(cb)
+    ], done)
   })
 
   it('add tcp', (done) => {
@@ -214,7 +209,9 @@ describe('high level API - with everything mixed all together!', function () {
   })
 
   it('close a muxer emits event', (done) => {
-    swarmC.close(() => {})
+    swarmC.close((err) => {
+      if (err) throw err
+    })
     swarmA.once('peer-mux-closed', (peerInfo) => {
       done()
     })
diff --git a/test/browser.js b/test/browser.js
index bcd92cb..dc3ea2b 100644
--- a/test/browser.js
+++ b/test/browser.js
@@ -73,8 +73,7 @@ describe('high level API - 1st without stream multiplexing (on websockets)', fun
   })
 
   after((done) => {
-    done()
-    // swarm.close(done)
+    swarm.close(done)
   })
 
   it('add ws', (done) => {