diff --git a/README.md b/README.md
index 5b7fce7..0549f54 100644
--- a/README.md
+++ b/README.md
@@ -236,6 +236,25 @@ abs({
 })
 ```
 
+If you require some async stuff before returning, a callback is also
+supported:
+
+```js
+var test = require('tape').test
+var myperst = require('./')
+var abs = require('aedes-persistence/abstract')
+var clean = require('./clean') // invented module
+
+abs({
+  test: test,
+  persistence: function build (cb) {
+    clean(function (err) {
+      cb(err, myperst())
+    })
+  }
+})
+```
+
 ## License
 
 MIT
diff --git a/abstract.js b/abstract.js
index 6b0cb37..bd0d452 100644
--- a/abstract.js
+++ b/abstract.js
@@ -8,6 +8,12 @@ function abstractPersistence (opts) {
   var test = opts.test
   var persistence = opts.persistence
 
+  if (persistence.length === 0) {
+    persistence = function asyncify (cb) {
+      cb(null, opts.persistence())
+    }
+  }
+
   function storeRetained (instance, opts, cb) {
     opts = opts || {}
 
@@ -26,16 +32,27 @@ function abstractPersistence (opts) {
   }
 
   function matchRetainedWithPattern (t, pattern, opts) {
-    var instance = persistence()
+    persistence(function (err, instance) {
+      if (err) { throw err }
 
-    storeRetained(instance, opts, function (err, packet) {
-      t.notOk(err, 'no error')
-      var stream = instance.createRetainedStream(pattern)
+      storeRetained(instance, opts, function (err, packet) {
+        t.notOk(err, 'no error')
+        var stream = instance.createRetainedStream(pattern)
 
-      stream.pipe(concat(function (list) {
-        t.deepEqual(list, [packet], 'must return the packet')
-        instance.destroy(t.end.bind(t))
-      }))
+        stream.pipe(concat(function (list) {
+          t.deepEqual(list, [packet], 'must return the packet')
+          instance.destroy(t.end.bind(t))
+        }))
+      })
+    })
+  }
+
+  function testInstance (title, cb) {
+    test(title, function (t) {
+      persistence(function (err, instance) {
+        if (err) { throw err }
+        cb(t, instance)
+      })
     })
   }
 
@@ -51,8 +68,7 @@ function abstractPersistence (opts) {
     matchRetainedWithPattern(t, 'hello/+')
   })
 
-  test('remove retained message', function (t) {
-    var instance = persistence()
+  testInstance('remove retained message', function (t, instance) {
     storeRetained(instance, {}, function (err, packet) {
       t.notOk(err, 'no error')
       storeRetained(instance, {
@@ -70,8 +86,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('storing twice a retained message should keep only the last', function (t) {
-    var instance = persistence()
+  testInstance('storing twice a retained message should keep only the last', function (t, instance) {
     storeRetained(instance, {}, function (err, packet) {
       t.notOk(err, 'no error')
       storeRetained(instance, {
@@ -89,8 +104,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('store and look up subscriptions by client', function (t) {
-    var instance = persistence()
+  testInstance('store and look up subscriptions by client', function (t, instance) {
     var client = { id: 'abcde' }
     var subs = [{
       topic: 'hello',
@@ -115,8 +129,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('remove subscriptions by client', function (t) {
-    var instance = persistence()
+  testInstance('remove subscriptions by client', function (t, instance) {
     var client = { id: 'abcde' }
     var subs = [{
       topic: 'hello',
@@ -144,8 +157,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('store and look up subscriptions by topic', function (t) {
-    var instance = persistence()
+  testInstance('store and look up subscriptions by topic', function (t, instance) {
     var client = { id: 'abcde' }
     var subs = [{
       topic: 'hello',
@@ -176,8 +188,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('QoS 0 subscriptions, restored but not matched', function (t) {
-    var instance = persistence()
+  testInstance('QoS 0 subscriptions, restored but not matched', function (t, instance) {
     var client = { id: 'abcde' }
     var subs = [{
       topic: 'hello',
@@ -208,8 +219,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('clean subscriptions', function (t) {
-    var instance = persistence()
+  testInstance('clean subscriptions', function (t, instance) {
     var client = { id: 'abcde' }
     var subs = [{
       topic: 'hello',
@@ -237,8 +247,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('store and count subscriptions', function (t) {
-    var instance = persistence()
+  testInstance('store and count subscriptions', function (t, instance) {
     var client = { id: 'abcde' }
     var subs = [{
       topic: 'hello',
@@ -275,8 +284,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('add outgoing packet and stream it', function (t) {
-    var instance = persistence()
+  testInstance('add outgoing packet and stream it', function (t, instance) {
     var sub = {
       clientId: 'abcde',
       topic: 'hello',
@@ -318,8 +326,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('add outgoing packet and stream it twice', function (t) {
-    var instance = persistence()
+  testInstance('add outgoing packet and stream it twice', function (t, instance) {
     var sub = {
       clientId: 'abcde',
       topic: 'hello',
@@ -384,8 +391,7 @@ function abstractPersistence (opts) {
     })
   }
 
-  test('add outgoing packet and update messageId', function (t) {
-    var instance = persistence()
+  testInstance('add outgoing packet and update messageId', function (t, instance) {
     var sub = {
       clientId: 'abcde', topic: 'hello', qos: 1
     }
@@ -414,8 +420,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('add 2 outgoing packet and clear messageId', function (t) {
-    var instance = persistence()
+  testInstance('add 2 outgoing packet and clear messageId', function (t, instance) {
     var sub = {
       clientId: 'abcde', topic: 'hello', qos: 1
     }
@@ -461,8 +466,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('update to pubrel', function (t) {
-    var instance = persistence()
+  testInstance('update to pubrel', function (t, instance) {
     var sub = {
       clientId: 'abcde', topic: 'hello', qos: 1
     }
@@ -510,8 +514,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('add incoming packet, get it, and clear with messageId', function (t) {
-    var instance = persistence()
+  testInstance('add incoming packet, get it, and clear with messageId', function (t, instance) {
     var client = {
       id: 'abcde'
     }
@@ -557,8 +560,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('store, fetch and delete will message', function (t) {
-    var instance = persistence()
+  testInstance('store, fetch and delete will message', function (t, instance) {
     var broker = {
       id: 'mybrokerId'
     }
@@ -596,8 +598,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('stream all will messages', function (t) {
-    var instance = persistence()
+  testInstance('stream all will messages', function (t, instance) {
     var broker = {
       id: 'mybrokerId'
     }
@@ -630,8 +631,7 @@ function abstractPersistence (opts) {
     })
   })
 
-  test('stream all will message for unknown brokers', function (t) {
-    var instance = persistence()
+  testInstance('stream all will message for unknown brokers', function (t, instance) {
     var broker = {
       id: 'mybrokerId'
     }
diff --git a/package.json b/package.json
index 064edf7..660daae 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "aedes-persistence",
-  "version": "1.0.2",
+  "version": "1.1.0",
   "description": "The spec for an Aedes persistence, with abstract tests and a fast in-memory implementation.",
   "main": "persistence.js",
   "scripts": {