diff --git a/README.md b/README.md
index 89ac288..b54ac36 100644
--- a/README.md
+++ b/README.md
@@ -129,6 +129,7 @@ $result = $query->execute();
 foreach ($result as $row) {
     echo 'Author ', $row['key'], ' has written ', $row['value'], ' articles', "\n";
 }
+
 // Author Alice has written 1 articles
 // Author Bob has written 2 articles
-```
\ No newline at end of file
+```
diff --git a/composer.json b/composer.json
index 9eb79eb..115b8e0 100644
--- a/composer.json
+++ b/composer.json
@@ -13,7 +13,7 @@
         "php": ">=5.4"
     },
     "require-dev": {
-      "phpunit/phpunit": "~4.0"
+      "phpunit/phpunit": "^4.8.35"
     },
     "autoload": {
         "psr-0": {
diff --git a/tests/Doctrine/Tests/CouchDB/CouchDBClientTest.php b/tests/Doctrine/Tests/CouchDB/CouchDBClientTest.php
index 1d1caea..c2d4cf4 100644
--- a/tests/Doctrine/Tests/CouchDB/CouchDBClientTest.php
+++ b/tests/Doctrine/Tests/CouchDB/CouchDBClientTest.php
@@ -4,8 +4,9 @@
 
 use Doctrine\CouchDB\CouchDBClient;
 use Doctrine\CouchDB\HTTP\SocketClient;
+use PHPUnit\Framework\TestCase;
 
-class CouchDBClientTest extends \PHPUnit_Framework_TestCase
+class CouchDBClientTest extends TestCase
 {
     public function testConstants()
     {
diff --git a/tests/Doctrine/Tests/CouchDB/CouchDBExceptionTest.php b/tests/Doctrine/Tests/CouchDB/CouchDBExceptionTest.php
index 17f584e..aae90b0 100644
--- a/tests/Doctrine/Tests/CouchDB/CouchDBExceptionTest.php
+++ b/tests/Doctrine/Tests/CouchDB/CouchDBExceptionTest.php
@@ -3,11 +3,12 @@
 namespace Doctrine\Tests\CouchDB;
 
 use Doctrine\CouchDB\CouchDBException;
+use PHPUnit\Framework\TestCase;
 
 /**
  * @covers \Doctrine\CouchDB\CouchDBException
  */
-class CouchDBExceptionTest extends \PHPUnit_Framework_TestCase
+class CouchDBExceptionTest extends TestCase
 {
     /**
      * @dataProvider staticFactoryDataProvider
diff --git a/tests/Doctrine/Tests/CouchDB/CouchDBFunctionalTestCase.php b/tests/Doctrine/Tests/CouchDB/CouchDBFunctionalTestCase.php
index 3a917cd..6db0b89 100644
--- a/tests/Doctrine/Tests/CouchDB/CouchDBFunctionalTestCase.php
+++ b/tests/Doctrine/Tests/CouchDB/CouchDBFunctionalTestCase.php
@@ -4,8 +4,9 @@
 
 use Doctrine\CouchDB\CouchDBClient;
 use Doctrine\CouchDB\HTTP\SocketClient;
+use PHPUnit\Framework\TestCase;
 
-abstract class CouchDBFunctionalTestCase extends \PHPUnit_Framework_TestCase
+abstract class CouchDBFunctionalTestCase extends TestCase
 {
     private $httpClient = null;