diff --git a/makefile b/makefile
index 175e0dc..0c357ba 100644
--- a/makefile
+++ b/makefile
@@ -16,4 +16,12 @@ test-report:
 		--reporter markdown \
 		test/unit > ./test-unit.md
 
+test-perf:
+	@NODE_ENV=test ./node_modules/.bin/mocha $(T) \
+		--compilers coffee:coffee-script \
+		--recursive \
+		--reporter $(REPORTER) \
+		--timeout 5000 \
+		test/perf
+
 .PHONY: test test-report
diff --git a/package.json b/package.json
index 0ed5b93..dc75409 100644
--- a/package.json
+++ b/package.json
@@ -8,11 +8,13 @@
     , "moment": "2.1.0"
   },
   "devDependencies": {
-    "should": "1.2.2"
-    , "sinon": "v1.7.3"
+    "sinon": "v1.7.3"
     , "mocha": "1.12.1"
     , "async": "0.2.5"
     , "coffee-script": "1.5.0"
+    , "memwatch": "v0.2.2"
+    , "winston": "v0.7.3"
+    , "chalk": "v0.4.0"
   },
   "keywords": [
     "nodeJs"
diff --git a/test/bootstrap-perf.coffee b/test/bootstrap-perf.coffee
new file mode 100644
index 0000000..f52e420
--- /dev/null
+++ b/test/bootstrap-perf.coffee
@@ -0,0 +1,4 @@
+mongoose = require 'mongoose'
+
+mongoose.connect "mongodb://127.0.0.1:27017/mongoose-rattle-test-perf", {}, (err) ->
+  throw err if err
diff --git a/test/perf-data.coffee b/test/perf-data.coffee
new file mode 100644
index 0000000..14bc944
--- /dev/null
+++ b/test/perf-data.coffee
@@ -0,0 +1,86 @@
+require './bootstrap-perf'
+
+mongoose = require 'mongoose'
+async    = require 'async'
+winston  = require 'winston'
+
+winston.remove winston.transports.Console
+winston.add winston.transports.Console, colorize: true
+
+Thingy   = require './models/thingy'
+
+ObjectId  = mongoose.Types.ObjectId;
+
+numThingies = 5
+numLikes = 20000
+numCommentLikes = 20
+blockNumComments = 5000
+numBlocks = 4
+
+i = 0
+likes = []
+while i < numCommentLikes
+  likes.push new ObjectId()
+  i++
+
+dummyComment =
+  message:       'duuuuuuuuuuuummmmmmmmmmmmmmmmyyyyyyyyyyyyy meeeeeeeeeeeeessssssssssssaaaaaaaaaaaaaageeeeee'
+  creator:       new ObjectId()
+  likes:         likes
+  likesCount:    type: Number, default: 0
+  dateCreation:  type: Date
+  dateUpdate:    type: Date
+
+i = 0
+comments = []
+while i < blockNumComments
+  comments.push dummyComment
+  i++
+
+createNewThingy = (callback) ->
+  async.waterfall [
+    createThingy = (next) ->
+      winston.info('Create a new thingy');
+      new Thingy(
+        creator: new ObjectId()
+      ).save next
+    addComments = (createdThingy, numAffected, next) ->
+      winston.info('Add comments with likes');
+
+      i = 0
+      async.whilst (->
+        i < numBlocks
+      ), ((callback) ->
+        winston.info('Add block ' + (i + 1) + ' of ' + blockNumComments + ' comments');
+        Thingy.update { _id: createdThingy._id }, { $pushAll: { comments: comments } }, (err) ->
+          i++
+          callback()
+      ), (err) ->
+        winston.info('Add likes');
+        i = 0
+        likes = []
+        while i < numLikes
+          likes.push new ObjectId()
+          i++
+        createdThingy.likes = likes
+        createdThingy.save next
+      
+  ], (err) ->
+    return callback(err) if err
+    winston.info('Thingy saved');
+    callback()
+
+
+winston.info('Clear thingy collection');
+Thingy.remove (err) ->
+  count = 0
+  async.whilst (->
+    count < numThingies
+  ), ((next) ->
+    createNewThingy (err) ->
+      return next(err) if err
+      count++
+      next()
+  ), (err) ->
+    winston.error err if err
+    process.exit(1);
\ No newline at end of file
diff --git a/test/perf-stats.coffee b/test/perf-stats.coffee
new file mode 100644
index 0000000..8f38e9d
--- /dev/null
+++ b/test/perf-stats.coffee
@@ -0,0 +1,78 @@
+require './bootstrap-perf'
+
+mongoose = require 'mongoose'
+async    = require 'async'
+memwatch = require 'memwatch'
+chalk    = require 'chalk'
+
+log = (level, msg) ->
+  console.log(Array(level).join('  ') + msg)
+title = (msg) ->
+   log(1, chalk.bold.magenta.underline(msg))
+description = (msg) ->
+   log(1, chalk.bold.italic(msg))
+target = (msg) ->
+   log(2, chalk.green(msg))
+info = (msg) ->
+   log(4, chalk.blue(msg))
+
+Thingy   = require './models/thingy'
+
+numOccurence = 3
+
+# hd = new memwatch.HeapDiff()
+# diff = hd.end()
+# log.info('memory diff after the operation (in bytes): ' + diff.change.size_bytes)
+
+task = () ->
+  msg      = arguments[0]
+  obj      = arguments[1]
+  fctName  = arguments[2]
+  args     = Array::slice.call(arguments, 3, arguments.length - 1)
+  callback = arguments[arguments.length - 1]
+
+  log(3, chalk.yellow(msg))
+  count = 1
+  totalTime = 0
+  async.whilst (->
+    count <= numOccurence
+  ), ((next) ->
+    start = Date.now()
+
+    cb = (err) ->
+      return next(err) if err
+      end = Date.now()
+      time = end - start
+      totalTime += time
+      info("[iteration #{count}] time for the operation (in ms): #{time}")
+      count++
+      next()
+
+    fctArgs = args.slice(0)
+    fctArgs.push(cb)
+    obj[fctName].apply obj, fctArgs
+    return
+  ), (err) ->
+    return callback(err) if err
+    avg = Math.ceil(totalTime / numOccurence)
+    info("=> average time: #{avg}")
+    callback()
+
+title("Benchmarking rattle plugin (number of occurence: #{numOccurence})")
+description('In collections: 2 documents with 20000 likes, 20000 comments with 20 likes each')
+
+# describe 'Thingy', ->
+#   describe 'getList', ->
+#     analyse('retrieve 2 documents with no comments', Thingy, 'getList', 2, 0, next)
+#     analyse('retrieve 3 documents with the last 5 comments', Thingy, 'getList', 3, 5, next)
+
+async.series [
+  getList = (done) ->
+    target('#getList')
+    async.series [
+      (next) ->
+        task('retrieve two documents with no comments', Thingy, 'getList', 2, 0, next)
+    ], done
+    
+], (err) ->
+  process.exit(1);
diff --git a/test/unit/index.coffee b/test/unit/index.coffee
index b96060f..ad17cf4 100644
--- a/test/unit/index.coffee
+++ b/test/unit/index.coffee
@@ -4,7 +4,6 @@ async    = require 'async'
 sinon    = require 'sinon'
 assert   = require 'assert'
 moment   = require 'moment'
-should   = require 'should'
 mongoose = require 'mongoose'
 
 Thingy   = require '../models/thingy'
@@ -23,14 +22,14 @@ describe "MongooseRattlePlugin", ->
   describe "document.save(callback)", ->
     it "update dateCreation and dateUpdate when inserting", (done) ->
       clock = sinon.useFakeTimers()
-      new Thingy(creator: objectCreatorUserId, owner: objectCreatorUserId).save (err, thingySaved) ->
+      new Thingy(creator: objectCreatorUserId).save (err, thingySaved) ->
         assert.deepEqual(new Date(), thingySaved.dateCreation)
         assert.deepEqual(new Date(), thingySaved.dateUpdate)
         clock.restore()
         done()
     it "only update dateUpdate when updating", (done) ->
       clock = sinon.useFakeTimers(new Date(2011, 0, 1, 1, 1, 36).getTime())
-      new Thingy(creator: objectCreatorUserId, owner: objectCreatorUserId).save (err, thingySaved) ->
+      new Thingy(creator: objectCreatorUserId).save (err, thingySaved) ->
         clock.restore()
         clock = sinon.useFakeTimers(new Date(2012, 0, 1, 1, 1, 36).getTime())
         thingySaved.save (err, thingySaved) ->
@@ -41,7 +40,7 @@ describe "MongooseRattlePlugin", ->
 
   describe "Plugin methods", ->
     beforeEach (done) ->
-      new Thingy(creator: objectCreatorUserId, owner: objectCreatorUserId).save (err, thingySaved) ->
+      new Thingy(creator: objectCreatorUserId).save (err, thingySaved) ->
         thingy = thingySaved
         done()
 
@@ -75,10 +74,10 @@ describe "MongooseRattlePlugin", ->
     describe "document.addComment(userId, message, callback)", ->
       it "append a new comment and return comment id", (done) ->
         commentId = thingy.addComment commentorUserId, 'dummy message', (err) ->
-          should.not.exists(err)
-          should.exists(commentId)
+          assert !err
+          assert commentId
           Thingy.findById thingy._id, (err, updatedThingy) ->
-            should.exists(updatedThingy)
+            assert updatedThingy
             assert.equal(1, updatedThingy.comments.length)
             done()
       it "update dateCreation and dateUpdated", (done) ->
@@ -90,7 +89,7 @@ describe "MongooseRattlePlugin", ->
           done()
       it "fails if message length is out of min and max", (done) ->
         thingy.addComment commentorUserId, '', (err) ->
-          should.exists(err)
+          assert err
           done()
 
     describe "document.editComment(userId, commentId, message, callback)", ->
@@ -104,20 +103,20 @@ describe "MongooseRattlePlugin", ->
 
       it "fails if message length is out of min and max", (done) ->
         thingy.editComment commentorUserId, commentId, '', (err) ->
-          should.exists(err)
+          assert err
           done()
       describe 'when user is not the creator', ->
         it "always fails", (done) ->
           thingy.editComment 'n0t3x1t1n9', commentId, updatedMessage, (err) ->
-            should.exists(err)
+            assert err
             done()
       describe 'when user is the creator', ->
         checkEditCommentWhenOwner = (commentorUserId, commentId, updatedMessage, done) ->
           thingy.editComment commentorUserId, commentId, updatedMessage, (err) ->
-            should.not.exists(err)
-            should.exists(commentId)
+            assert !err
+            assert commentId
             Thingy.findById thingy._id, (err, updatedThingy) ->
-              should.exists(updatedThingy)
+              assert updatedThingy
               assert.equal(1, updatedThingy.comments.length)
               assert.equal(updatedMessage, updatedThingy.comments[0].message)
               done()
@@ -150,29 +149,29 @@ describe "MongooseRattlePlugin", ->
 
       it "fails if comment doesn't exist", (done) ->
         thingy.removeComment commentorUserId, 'n0t3x1t1n9', (err, updatedThingy) ->
-          should.exists(err)
+          assert err
           done()
       describe 'when user is not the creator', ->
         it "it's not removing the comment", (done) ->
           thingy.removeComment 'n0t3x1t1n9', commentIds['level 1'], (err, updatedThingy) ->
-            should.exists(updatedThingy)
-            should.exists(updatedThingy.getComment(commentIds['level 1']))
+            assert updatedThingy
+            assert updatedThingy.getComment(commentIds['level 1'])
             done()
       describe 'when user is the creator', ->
         it "can remove comment", (done) ->
           thingy.removeComment commentorUserId, commentIds['level 1'], (err, updatedThingy) ->
-            should.exists(updatedThingy)
-            should.not.exists(updatedThingy.getComment(commentIds['level 1']))
+            assert updatedThingy
+            assert !updatedThingy.getComment(commentIds['level 1'])
             done()
         it "remove comment when userId param is a string", (done) ->
           thingy.removeComment String(commentorUserId), commentIds['level 1'], (err, updatedThingy) ->
-            should.exists(updatedThingy)
-            should.not.exists(updatedThingy.getComment(commentIds['level 1']))
+            assert updatedThingy
+            assert !updatedThingy.getComment(commentIds['level 1'])
             done()
         it "remove comment when commentId is a string", (done) ->
           thingy.removeComment commentorUserId, String(commentIds['level 1']), (err, updatedThingy) ->
-            should.exists(updatedThingy)
-            should.not.exists(updatedThingy.getComment(commentIds['level 1']))
+            assert updatedThingy
+            assert !updatedThingy.getComment(commentIds['level 1'])
             done()
 
     describe "document.addLike(userId, callback)", ->
@@ -253,7 +252,7 @@ describe "MongooseRattlePlugin", ->
 
       it "fails if comment doesn't exist", (done) ->
         thingy.addLikeToComment commentorUserId, 'n0t3x1t1n9', (err, updatedThingy) ->
-          should.exists(err)
+          assert err
           done()
       it "add one user like if user doesn't already liked and comment exists", (done) ->
         thingy.addLikeToComment commentorUserId, commentId, (err, updatedThingy) ->
@@ -285,7 +284,7 @@ describe "MongooseRattlePlugin", ->
 
       it "fails if comment doesn't exist", (done) ->
         thingy.removeLikeFromComment commentorUserId, 'n0t3x1t1n9', (err, updatedThingy) ->
-          should.exists(err)
+          assert err
           done()
       it "not affect current likes list if user didn'nt already liked", (done) ->
         thingy.removeLikeFromComment new ObjectId(), commentId, (err, updatedThingy) ->
@@ -335,7 +334,7 @@ describe "MongooseRattlePlugin", ->
         it "get list of the number of 'num' last rattles and return likesCount instead of likes array", (done) ->
           Thingy.find {}, (err, rattles) ->
             Thingy.getList 1, 0, (err, rattles) ->
-              should.not.exists(err)
+              assert !err
               assert.equal rattles.length, 1
               assert.deepEqual rattles[0].creator, creator2Id
               assert !rattles[0].likes
@@ -343,23 +342,23 @@ describe "MongooseRattlePlugin", ->
               done()
         it "get all rattles if 'num' is greater than the number of rattles", (done) ->
           Thingy.getList 3, 0, (err, rattles) ->
-            should.not.exists(err)
+            assert !err
             assert.equal rattles.length, 2
             done()
         it "each rattle get the maximum of 'maxLastComments' last comments", (done) ->
           Thingy.getList 1, 1, (err, rattles) ->
-            should.not.exists(err)
+            assert !err
             assert.equal rattles.length, 1
             assert.deepEqual rattles[0].creator, creator2Id
-            should.exists(rattles[0].comments)
+            assert rattles[0].comments
             assert.equal rattles[0].comments.length, 1
             assert.equal rattles[0].comments[0].message, '22'
             done()
         it "each all comments when 'maxLastComments' is greater than number of comments", (done) ->
           Thingy.getList 1, 3, (err, rattles) ->
-            should.not.exists(err)
+            assert !err
             assert.equal rattles.length, 1
-            should.exists(rattles[0].comments)
+            assert rattles[0].comments
             assert.equal rattles[0].comments.length, 2
             done()
       describe "(num, maxNumLastPostComments, options, callback)", ->
@@ -368,7 +367,7 @@ describe "MongooseRattlePlugin", ->
             # retrieve last rattle
             Thingy.getList 1, 0, (err, rattles) ->
               Thingy.getList 1, 0, fromCreationDate: rattles[0].dateCreation, (err, rattles) ->
-                should.not.exists(err)
+                assert !err
                 assert.equal rattles.length, 1
                 assert.deepEqual rattles[0].creator, creator1Id
                 done()
@@ -376,17 +375,17 @@ describe "MongooseRattlePlugin", ->
             # retrieve last rattle
             Thingy.getList 1, 0, (err, rattles) ->
               Thingy.getList 2, 0, fromCreationDate: rattles[0].dateCreation, (err, rattles) ->
-                should.not.exists(err)
+                assert !err
                 assert.equal rattles.length, 1
                 done()
           it "each rattle get the maximum of 'maxLastComments' last comments", (done) ->
             # retrieve last rattle
             Thingy.getList 1, 0, (err, rattles) ->
               Thingy.getList 1, 1, fromCreationDate: rattles[0].dateCreation, (err, rattles) ->
-                should.not.exists(err)
+                assert !err
                 assert.equal rattles.length, 1
                 assert.deepEqual rattles[0].creator, creator1Id
-                should.exists(rattles[0].comments)
+                assert rattles[0].comments
                 assert.equal rattles[0].comments.length, 1
                 assert.equal rattles[0].comments[0].message, '12'
                 done()
@@ -395,9 +394,9 @@ describe "MongooseRattlePlugin", ->
             new User({_id: creator2Id, name: 'Dummy Name'}).save (err) ->
               # retrieve last rattle
               Thingy.getList 1, 0, {populate: 'creator'}, (err, rattles) ->
-                  should.not.exists(err)
+                  assert !err
                   assert.equal rattles.length, 1
-                  should.exists(rattles[0].creator.name)
+                  assert rattles[0].creator.name
                   assert.equal rattles[0].creator.name, 'Dummy Name'
                   done()
 
@@ -431,31 +430,31 @@ describe "MongooseRattlePlugin", ->
 
       it "get last 'num' of comments for 'rattleId' when offsetFromEnd is 0", (done) ->
         Thingy.getListOfCommentsById rattleId, 1, 0, (err, comments) ->
-          should.not.exists(err)
+          assert !err
           assert.equal comments.length, 1
           assert.equal comments[0].message, '13'
           done()
       it "get last num of comments from the offsetFromEnd", (done) ->
         Thingy.getListOfCommentsById rattleId, 1, 1, (err, comments) ->
-          should.not.exists(err)
+          assert !err
           assert.equal comments.length, 1
           assert.equal comments[0].message, '12'
           done()
       it "get no comments when offsetFromEnd is equal to the number of comments", (done) ->
         Thingy.getListOfCommentsById rattleId, 1, 3, (err, comments) ->
-          should.not.exists(err)
+          assert !err
           assert.equal comments.length, 0
           done()
       it "limit comments when offsetFromEnd + num is greater that the number of comments", (done) ->
         Thingy.getListOfCommentsById rattleId, 3, 1, (err, comments) ->
-          should.not.exists(err)
+          assert !err
           assert.equal comments[0].message, '11'
           assert.equal comments[1].message, '12'
           assert.equal comments.length, 2
           done()
       it "keep comments order", (done) ->
         Thingy.getListOfCommentsById rattleId, 3, 0, (err, comments) ->
-          should.not.exists(err)
+          assert !err
           assert.equal comments[0].message, '11'
           assert.equal comments[1].message, '12'
           assert.equal comments[2].message, '13'