diff --git a/.travis.yml b/.travis.yml
index b617fd5fe..77a0bb27e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,8 +1,6 @@
 language: php
 
 php:
-  - 5.3
-  - 5.4
   - 5.5
   - 5.6
   - hhvm
diff --git a/composer.json b/composer.json
index ef890824d..ed94e7175 100644
--- a/composer.json
+++ b/composer.json
@@ -15,11 +15,11 @@
         }
     ],
     "require": {
-        "php": ">=5.3.0"
+        "php": ">=5.5.0"
     },
     "require-dev": {
-        "phpunit/php-code-coverage": "~3.0",
-        "phpunit/phpunit": "~5.1"
+        "phpunit/php-code-coverage": "~2.0",
+        "phpunit/phpunit": "~4.8"
     },
     "autoload": {
         "psr-4": {
diff --git a/composer.lock b/composer.lock
index 7885f48b8..3c706f00a 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,8 +4,8 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
         "This file is @generated automatically"
     ],
-    "hash": "457f267fae4959658b21a18d2a55aebd",
-    "content-hash": "399e9f63cfa5b2904eeccce1dadc262a",
+    "hash": "a8aac8e76b450a2dd7b8e859f76c6046",
+    "content-hash": "7cd132a6d7bc519a273dbdafa3644e16",
     "packages": [],
     "packages-dev": [
         {
@@ -62,48 +62,6 @@
             ],
             "time": "2015-06-14 21:17:01"
         },
-        {
-            "name": "myclabs/deep-copy",
-            "version": "1.5.0",
-            "source": {
-                "type": "git",
-                "url": "https://github.com/myclabs/DeepCopy.git",
-                "reference": "e3abefcd7f106677fd352cd7c187d6c969aa9ddc"
-            },
-            "dist": {
-                "type": "zip",
-                "url": "https://api.github.com/repos/myclabs/DeepCopy/zipball/e3abefcd7f106677fd352cd7c187d6c969aa9ddc",
-                "reference": "e3abefcd7f106677fd352cd7c187d6c969aa9ddc",
-                "shasum": ""
-            },
-            "require": {
-                "php": ">=5.4.0"
-            },
-            "require-dev": {
-                "doctrine/collections": "1.*",
-                "phpunit/phpunit": "~4.1"
-            },
-            "type": "library",
-            "autoload": {
-                "psr-4": {
-                    "DeepCopy\\": "src/DeepCopy/"
-                }
-            },
-            "notification-url": "https://packagist.org/downloads/",
-            "license": [
-                "MIT"
-            ],
-            "description": "Create deep copies (clones) of your objects",
-            "homepage": "https://github.com/myclabs/DeepCopy",
-            "keywords": [
-                "clone",
-                "copy",
-                "duplicate",
-                "object",
-                "object graph"
-            ],
-            "time": "2015-11-07 22:20:37"
-        },
         {
             "name": "phpdocumentor/reflection-docblock",
             "version": "2.0.4",
@@ -215,20 +173,20 @@
         },
         {
             "name": "phpunit/php-code-coverage",
-            "version": "3.0.2",
+            "version": "2.2.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/sebastianbergmann/php-code-coverage.git",
-                "reference": "f7bb5cddf4ffe113eeb737b05241adb947b43f9d"
+                "reference": "eabf68b476ac7d0f73793aada060f1c1a9bf8979"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/php-code-coverage/zipball/f7bb5cddf4ffe113eeb737b05241adb947b43f9d",
-                "reference": "f7bb5cddf4ffe113eeb737b05241adb947b43f9d",
+                "url": "https://api.github.com/repos/sebastianbergmann/php-code-coverage/zipball/eabf68b476ac7d0f73793aada060f1c1a9bf8979",
+                "reference": "eabf68b476ac7d0f73793aada060f1c1a9bf8979",
                 "shasum": ""
             },
             "require": {
-                "php": ">=5.6",
+                "php": ">=5.3.3",
                 "phpunit/php-file-iterator": "~1.3",
                 "phpunit/php-text-template": "~1.2",
                 "phpunit/php-token-stream": "~1.3",
@@ -237,7 +195,7 @@
             },
             "require-dev": {
                 "ext-xdebug": ">=2.1.4",
-                "phpunit/phpunit": "~5"
+                "phpunit/phpunit": "~4"
             },
             "suggest": {
                 "ext-dom": "*",
@@ -247,7 +205,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.0.x-dev"
+                    "dev-master": "2.2.x-dev"
                 }
             },
             "autoload": {
@@ -273,7 +231,7 @@
                 "testing",
                 "xunit"
             ],
-            "time": "2015-11-12 21:08:20"
+            "time": "2015-10-06 15:47:00"
         },
         {
             "name": "phpunit/php-file-iterator",
@@ -455,16 +413,16 @@
         },
         {
             "name": "phpunit/phpunit",
-            "version": "5.1.3",
+            "version": "4.8.21",
             "source": {
                 "type": "git",
                 "url": "https://github.com/sebastianbergmann/phpunit.git",
-                "reference": "c047ff05d2279404af9a7e89e2a7151c32c88022"
+                "reference": "ea76b17bced0500a28098626b84eda12dbcf119c"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/phpunit/zipball/c047ff05d2279404af9a7e89e2a7151c32c88022",
-                "reference": "c047ff05d2279404af9a7e89e2a7151c32c88022",
+                "url": "https://api.github.com/repos/sebastianbergmann/phpunit/zipball/ea76b17bced0500a28098626b84eda12dbcf119c",
+                "reference": "ea76b17bced0500a28098626b84eda12dbcf119c",
                 "shasum": ""
             },
             "require": {
@@ -473,20 +431,18 @@
                 "ext-pcre": "*",
                 "ext-reflection": "*",
                 "ext-spl": "*",
-                "myclabs/deep-copy": "~1.3",
-                "php": ">=5.6",
+                "php": ">=5.3.3",
                 "phpspec/prophecy": "^1.3.1",
-                "phpunit/php-code-coverage": "~3.0",
+                "phpunit/php-code-coverage": "~2.1",
                 "phpunit/php-file-iterator": "~1.4",
                 "phpunit/php-text-template": "~1.2",
                 "phpunit/php-timer": ">=1.0.6",
-                "phpunit/phpunit-mock-objects": ">=3.0.5",
+                "phpunit/phpunit-mock-objects": "~2.3",
                 "sebastian/comparator": "~1.1",
                 "sebastian/diff": "~1.2",
                 "sebastian/environment": "~1.3",
                 "sebastian/exporter": "~1.2",
                 "sebastian/global-state": "~1.0",
-                "sebastian/resource-operations": "~1.0",
                 "sebastian/version": "~1.0",
                 "symfony/yaml": "~2.1|~3.0"
             },
@@ -499,7 +455,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "5.1.x-dev"
+                    "dev-master": "4.8.x-dev"
                 }
             },
             "autoload": {
@@ -525,30 +481,30 @@
                 "testing",
                 "xunit"
             ],
-            "time": "2015-12-10 07:54:54"
+            "time": "2015-12-12 07:45:58"
         },
         {
             "name": "phpunit/phpunit-mock-objects",
-            "version": "3.0.6",
+            "version": "2.3.8",
             "source": {
                 "type": "git",
                 "url": "https://github.com/sebastianbergmann/phpunit-mock-objects.git",
-                "reference": "49bc700750196c04dd6bc2c4c99cb632b893836b"
+                "reference": "ac8e7a3db35738d56ee9a76e78a4e03d97628983"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/phpunit-mock-objects/zipball/49bc700750196c04dd6bc2c4c99cb632b893836b",
-                "reference": "49bc700750196c04dd6bc2c4c99cb632b893836b",
+                "url": "https://api.github.com/repos/sebastianbergmann/phpunit-mock-objects/zipball/ac8e7a3db35738d56ee9a76e78a4e03d97628983",
+                "reference": "ac8e7a3db35738d56ee9a76e78a4e03d97628983",
                 "shasum": ""
             },
             "require": {
                 "doctrine/instantiator": "^1.0.2",
-                "php": ">=5.6",
+                "php": ">=5.3.3",
                 "phpunit/php-text-template": "~1.2",
                 "sebastian/exporter": "~1.2"
             },
             "require-dev": {
-                "phpunit/phpunit": "~5"
+                "phpunit/phpunit": "~4.4"
             },
             "suggest": {
                 "ext-soap": "*"
@@ -556,7 +512,7 @@
             "type": "library",
             "extra": {
                 "branch-alias": {
-                    "dev-master": "3.0.x-dev"
+                    "dev-master": "2.3.x-dev"
                 }
             },
             "autoload": {
@@ -581,7 +537,7 @@
                 "mock",
                 "xunit"
             ],
-            "time": "2015-12-08 08:47:06"
+            "time": "2015-10-02 06:51:40"
         },
         {
             "name": "sebastian/comparator",
@@ -919,48 +875,6 @@
             "homepage": "http://www.github.com/sebastianbergmann/recursion-context",
             "time": "2015-11-11 19:50:13"
         },
-        {
-            "name": "sebastian/resource-operations",
-            "version": "1.0.0",
-            "source": {
-                "type": "git",
-                "url": "https://github.com/sebastianbergmann/resource-operations.git",
-                "reference": "ce990bb21759f94aeafd30209e8cfcdfa8bc3f52"
-            },
-            "dist": {
-                "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/resource-operations/zipball/ce990bb21759f94aeafd30209e8cfcdfa8bc3f52",
-                "reference": "ce990bb21759f94aeafd30209e8cfcdfa8bc3f52",
-                "shasum": ""
-            },
-            "require": {
-                "php": ">=5.6.0"
-            },
-            "type": "library",
-            "extra": {
-                "branch-alias": {
-                    "dev-master": "1.0.x-dev"
-                }
-            },
-            "autoload": {
-                "classmap": [
-                    "src/"
-                ]
-            },
-            "notification-url": "https://packagist.org/downloads/",
-            "license": [
-                "BSD-3-Clause"
-            ],
-            "authors": [
-                {
-                    "name": "Sebastian Bergmann",
-                    "email": "sebastian@phpunit.de"
-                }
-            ],
-            "description": "Provides a list of PHP built-in functions that operate on resources",
-            "homepage": "https://www.github.com/sebastianbergmann/resource-operations",
-            "time": "2015-07-28 20:34:47"
-        },
         {
             "name": "sebastian/version",
             "version": "1.0.6",
@@ -1052,7 +966,7 @@
     "prefer-stable": false,
     "prefer-lowest": false,
     "platform": {
-        "php": ">=5.3.0"
+        "php": ">=5.5.0"
     },
     "platform-dev": []
 }