diff --git a/README.md b/README.md
index 0cf7b95b..93e3341e 100644
--- a/README.md
+++ b/README.md
@@ -79,7 +79,10 @@ This package is released under the MIT License. See the bundled [LICENSE](https:
 
 ## Credits
 
-This code is principally developed and maintained by [Alex Bilbie](https://twitter.com/alexbilbie).
+This code is principally developed and maintained by [Andy Millington](https://twitter.com/Sephster), [Brian 
+Retterer](https://twitter.com/bretterer), and [Simon Hamp](https://twitter.com/simonhamp).
+
+Between 2012 and 2017 this library was developed and maintained by [Alex Bilbie](https://alexbilbie.com/).
 
 Special thanks to [all of these awesome contributors](https://github.com/thephpleague/oauth2-server/contributors).
 
diff --git a/composer.json b/composer.json
index d6740aa4..d8d11125 100644
--- a/composer.json
+++ b/composer.json
@@ -13,7 +13,7 @@
         "defuse/php-encryption": "^2.1"
     },
     "require-dev": {
-        "phpunit/phpunit": "^4.8 || ^5.0",
+        "phpunit/phpunit": "^4.8.38 || ^5.7.21",
         "zendframework/zend-diactoros": "^1.0"
     },
     "repositories": [
diff --git a/examples/composer.json b/examples/composer.json
index 79ab47cd..ec7387cf 100644
--- a/examples/composer.json
+++ b/examples/composer.json
@@ -7,7 +7,8 @@
         "lcobucci/jwt": "^3.1",
         "paragonie/random_compat": "^2.0",
         "psr/http-message": "^1.0",
-        "defuse/php-encryption": "^2.1"
+        "defuse/php-encryption": "^2.1",
+        "zendframework/zend-diactoros": "^1.0"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/AuthorizationServer.php b/src/AuthorizationServer.php
index 42313bff..40386653 100644
--- a/src/AuthorizationServer.php
+++ b/src/AuthorizationServer.php
@@ -3,6 +3,7 @@
  * @author      Alex Bilbie <hello@alexbilbie.com>
  * @copyright   Copyright (c) Alex Bilbie
  * @license     http://mit-license.org/
+ *
  * @link        https://github.com/thephpleague/oauth2-server
  */
 
diff --git a/src/CryptTrait.php b/src/CryptTrait.php
index 805969b0..125a757e 100644
--- a/src/CryptTrait.php
+++ b/src/CryptTrait.php
@@ -1,9 +1,11 @@
 <?php
 /**
  * Public/private key encryption.
+ *
  * @author      Alex Bilbie <hello@alexbilbie.com>
  * @copyright   Copyright (c) Alex Bilbie
  * @license     http://mit-license.org/
+ *
  * @link        https://github.com/thephpleague/oauth2-server
  */
 
@@ -24,6 +26,7 @@ trait CryptTrait
      * @param string $unencryptedData
      *
      * @throws \LogicException
+     *
      * @return string
      */
     protected function encrypt($unencryptedData)
@@ -41,6 +44,7 @@ trait CryptTrait
      * @param string $encryptedData
      *
      * @throws \LogicException
+     *
      * @return string
      */
     protected function decrypt($encryptedData)
diff --git a/src/Grant/ImplicitGrant.php b/src/Grant/ImplicitGrant.php
index 9f000eb0..870e930a 100644
--- a/src/Grant/ImplicitGrant.php
+++ b/src/Grant/ImplicitGrant.php
@@ -27,11 +27,18 @@ class ImplicitGrant extends AbstractAuthorizeGrant
     private $accessTokenTTL;
 
     /**
-     * @param \DateInterval $accessTokenTTL
+     * @var string
      */
-    public function __construct(\DateInterval $accessTokenTTL)
+    private $queryDelimiter;
+
+    /**
+     * @param \DateInterval $accessTokenTTL
+     * @param string $queryDelimiter
+     */
+    public function __construct(\DateInterval $accessTokenTTL, $queryDelimiter = '#')
     {
         $this->accessTokenTTL = $accessTokenTTL;
+        $this->queryDelimiter = $queryDelimiter;
     }
 
     /**
@@ -95,7 +102,7 @@ class ImplicitGrant extends AbstractAuthorizeGrant
     public function canRespondToAuthorizationRequest(ServerRequestInterface $request)
     {
         return (
-            array_key_exists('response_type', $request->getQueryParams())
+            isset($request->getQueryParams()['response_type'])
             && $request->getQueryParams()['response_type'] === 'token'
             && isset($request->getQueryParams()['client_id'])
         );
@@ -204,7 +211,7 @@ class ImplicitGrant extends AbstractAuthorizeGrant
                         'expires_in'   => $accessToken->getExpiryDateTime()->getTimestamp() - (new \DateTime())->getTimestamp(),
                         'state'        => $authorizationRequest->getState(),
                     ],
-                    '#'
+                    $this->queryDelimiter
                 )
             );
 
diff --git a/src/ResponseTypes/AbstractResponseType.php b/src/ResponseTypes/AbstractResponseType.php
index 0c256f17..d013bab0 100644
--- a/src/ResponseTypes/AbstractResponseType.php
+++ b/src/ResponseTypes/AbstractResponseType.php
@@ -60,5 +60,4 @@ abstract class AbstractResponseType implements ResponseTypeInterface
     {
         $this->privateKey = $key;
     }
-
 }
diff --git a/tests/AuthorizationServerTest.php b/tests/AuthorizationServerTest.php
index 4fe21724..40458059 100644
--- a/tests/AuthorizationServerTest.php
+++ b/tests/AuthorizationServerTest.php
@@ -3,7 +3,6 @@
 namespace LeagueTests;
 
 use League\OAuth2\Server\AuthorizationServer;
-use League\OAuth2\Server\CryptKey;
 use League\OAuth2\Server\Exception\OAuthServerException;
 use League\OAuth2\Server\Grant\AuthCodeGrant;
 use League\OAuth2\Server\Grant\ClientCredentialsGrant;
@@ -21,11 +20,12 @@ use LeagueTests\Stubs\ScopeEntity;
 use LeagueTests\Stubs\StubResponseType;
 use LeagueTests\Stubs\UserEntity;
 use Psr\Http\Message\ResponseInterface;
+use PHPUnit\Framework\TestCase;
 use Zend\Diactoros\Response;
 use Zend\Diactoros\ServerRequest;
 use Zend\Diactoros\ServerRequestFactory;
 
-class AuthorizationServerTest extends \PHPUnit_Framework_TestCase
+class AuthorizationServerTest extends TestCase
 {
 
     const DEFAULT_SCOPE = 'basic';
diff --git a/tests/CryptKeyTest.php b/tests/CryptKeyTest.php
index c7f7f4a0..f4fd0659 100644
--- a/tests/CryptKeyTest.php
+++ b/tests/CryptKeyTest.php
@@ -3,8 +3,9 @@
 namespace LeagueTests\Utils;
 
 use League\OAuth2\Server\CryptKey;
+use PHPUnit\Framework\TestCase;
 
-class CryptKeyTest extends \PHPUnit_Framework_TestCase
+class CryptKeyTest extends TestCase
 {
     /**
      * @expectedException \LogicException
diff --git a/tests/CryptTraitTest.php b/tests/CryptTraitTest.php
index 8c7d2642..26427e59 100644
--- a/tests/CryptTraitTest.php
+++ b/tests/CryptTraitTest.php
@@ -2,10 +2,10 @@
 
 namespace LeagueTests\Utils;
 
-use League\OAuth2\Server\CryptKey;
 use LeagueTests\Stubs\CryptTraitStub;
+use PHPUnit\Framework\TestCase;
 
-class CryptTraitTest extends \PHPUnit_Framework_TestCase
+class CryptTraitTest extends TestCase
 {
     /**
      * @var \LeagueTests\Stubs\CryptTraitStub
diff --git a/tests/Grant/AbstractGrantTest.php b/tests/Grant/AbstractGrantTest.php
index 542c78dc..d0d9b3c8 100644
--- a/tests/Grant/AbstractGrantTest.php
+++ b/tests/Grant/AbstractGrantTest.php
@@ -3,7 +3,6 @@
 namespace LeagueTests\Grant;
 
 use League\Event\Emitter;
-use League\OAuth2\Server\CryptKey;
 use League\OAuth2\Server\Entities\AccessTokenEntityInterface;
 use League\OAuth2\Server\Entities\AuthCodeEntityInterface;
 use League\OAuth2\Server\Entities\RefreshTokenEntityInterface;
@@ -19,9 +18,10 @@ use LeagueTests\Stubs\AuthCodeEntity;
 use LeagueTests\Stubs\ClientEntity;
 use LeagueTests\Stubs\RefreshTokenEntity;
 use LeagueTests\Stubs\ScopeEntity;
+use PHPUnit\Framework\TestCase;
 use Zend\Diactoros\ServerRequest;
 
-class AbstractGrantTest extends \PHPUnit_Framework_TestCase
+class AbstractGrantTest extends TestCase
 {
     public function testGetSet()
     {
diff --git a/tests/Grant/AuthCodeGrantTest.php b/tests/Grant/AuthCodeGrantTest.php
index 4a1c6d4a..6b06fe37 100644
--- a/tests/Grant/AuthCodeGrantTest.php
+++ b/tests/Grant/AuthCodeGrantTest.php
@@ -2,7 +2,6 @@
 
 namespace LeagueTests\Grant;
 
-use League\OAuth2\Server\CryptKey;
 use League\OAuth2\Server\Entities\AccessTokenEntityInterface;
 use League\OAuth2\Server\Entities\RefreshTokenEntityInterface;
 use League\OAuth2\Server\Exception\OAuthServerException;
@@ -23,9 +22,10 @@ use LeagueTests\Stubs\RefreshTokenEntity;
 use LeagueTests\Stubs\ScopeEntity;
 use LeagueTests\Stubs\StubResponseType;
 use LeagueTests\Stubs\UserEntity;
+use PHPUnit\Framework\TestCase;
 use Zend\Diactoros\ServerRequest;
 
-class AuthCodeGrantTest extends \PHPUnit_Framework_TestCase
+class AuthCodeGrantTest extends TestCase
 {
 
     const DEFAULT_SCOPE = 'basic';
diff --git a/tests/Grant/ClientCredentialsGrantTest.php b/tests/Grant/ClientCredentialsGrantTest.php
index 8559490d..cfcdfba5 100644
--- a/tests/Grant/ClientCredentialsGrantTest.php
+++ b/tests/Grant/ClientCredentialsGrantTest.php
@@ -11,9 +11,10 @@ use LeagueTests\Stubs\AccessTokenEntity;
 use LeagueTests\Stubs\ClientEntity;
 use LeagueTests\Stubs\ScopeEntity;
 use LeagueTests\Stubs\StubResponseType;
+use PHPUnit\Framework\TestCase;
 use Zend\Diactoros\ServerRequest;
 
-class ClientCredentialsGrantTest extends \PHPUnit_Framework_TestCase
+class ClientCredentialsGrantTest extends TestCase
 {
     const DEFAULT_SCOPE = 'basic';
 
diff --git a/tests/Grant/ImplicitGrantTest.php b/tests/Grant/ImplicitGrantTest.php
index 6e175ea6..db62d09c 100644
--- a/tests/Grant/ImplicitGrantTest.php
+++ b/tests/Grant/ImplicitGrantTest.php
@@ -18,9 +18,10 @@ use LeagueTests\Stubs\CryptTraitStub;
 use LeagueTests\Stubs\ScopeEntity;
 use LeagueTests\Stubs\StubResponseType;
 use LeagueTests\Stubs\UserEntity;
+use PHPUnit\Framework\TestCase;
 use Zend\Diactoros\ServerRequest;
 
-class ImplicitGrantTest extends \PHPUnit_Framework_TestCase
+class ImplicitGrantTest extends TestCase
 {
     const DEFAULT_SCOPE = 'basic';
 
diff --git a/tests/Grant/PasswordGrantTest.php b/tests/Grant/PasswordGrantTest.php
index 8c4337ba..469044af 100644
--- a/tests/Grant/PasswordGrantTest.php
+++ b/tests/Grant/PasswordGrantTest.php
@@ -16,9 +16,10 @@ use LeagueTests\Stubs\RefreshTokenEntity;
 use LeagueTests\Stubs\ScopeEntity;
 use LeagueTests\Stubs\StubResponseType;
 use LeagueTests\Stubs\UserEntity;
+use PHPUnit\Framework\TestCase;
 use Zend\Diactoros\ServerRequest;
 
-class PasswordGrantTest extends \PHPUnit_Framework_TestCase
+class PasswordGrantTest extends TestCase
 {
     const DEFAULT_SCOPE = 'basic';
 
diff --git a/tests/Grant/RefreshTokenGrantTest.php b/tests/Grant/RefreshTokenGrantTest.php
index eb6e18fb..d7b3a8fd 100644
--- a/tests/Grant/RefreshTokenGrantTest.php
+++ b/tests/Grant/RefreshTokenGrantTest.php
@@ -16,9 +16,10 @@ use LeagueTests\Stubs\CryptTraitStub;
 use LeagueTests\Stubs\RefreshTokenEntity;
 use LeagueTests\Stubs\ScopeEntity;
 use LeagueTests\Stubs\StubResponseType;
+use PHPUnit\Framework\TestCase;
 use Zend\Diactoros\ServerRequest;
 
-class RefreshTokenGrantTest extends \PHPUnit_Framework_TestCase
+class RefreshTokenGrantTest extends TestCase
 {
     /**
      * @var CryptTraitStub
diff --git a/tests/Middleware/AuthorizationServerMiddlewareTest.php b/tests/Middleware/AuthorizationServerMiddlewareTest.php
index c44681e1..99118736 100644
--- a/tests/Middleware/AuthorizationServerMiddlewareTest.php
+++ b/tests/Middleware/AuthorizationServerMiddlewareTest.php
@@ -13,10 +13,11 @@ use LeagueTests\Stubs\AccessTokenEntity;
 use LeagueTests\Stubs\ClientEntity;
 use LeagueTests\Stubs\ScopeEntity;
 use LeagueTests\Stubs\StubResponseType;
+use PHPUnit\Framework\TestCase;
 use Zend\Diactoros\Response;
 use Zend\Diactoros\ServerRequestFactory;
 
-class AuthorizationServerMiddlewareTest extends \PHPUnit_Framework_TestCase
+class AuthorizationServerMiddlewareTest extends TestCase
 {
     const DEFAULT_SCOPE = 'basic';
 
diff --git a/tests/Middleware/ResourceServerMiddlewareTest.php b/tests/Middleware/ResourceServerMiddlewareTest.php
index 549c8003..2269c45a 100644
--- a/tests/Middleware/ResourceServerMiddlewareTest.php
+++ b/tests/Middleware/ResourceServerMiddlewareTest.php
@@ -8,10 +8,11 @@ use League\OAuth2\Server\Repositories\AccessTokenRepositoryInterface;
 use League\OAuth2\Server\ResourceServer;
 use LeagueTests\Stubs\AccessTokenEntity;
 use LeagueTests\Stubs\ClientEntity;
+use PHPUnit\Framework\TestCase;
 use Zend\Diactoros\Response;
 use Zend\Diactoros\ServerRequest;
 
-class ResourceServerMiddlewareTest extends \PHPUnit_Framework_TestCase
+class ResourceServerMiddlewareTest extends TestCase
 {
     public function testValidResponse()
     {
diff --git a/tests/ResourceServerTest.php b/tests/ResourceServerTest.php
index 8a3353cc..3120cad2 100644
--- a/tests/ResourceServerTest.php
+++ b/tests/ResourceServerTest.php
@@ -6,9 +6,10 @@ namespace LeagueTests;
 use League\OAuth2\Server\Exception\OAuthServerException;
 use League\OAuth2\Server\Repositories\AccessTokenRepositoryInterface;
 use League\OAuth2\Server\ResourceServer;
+use PHPUnit\Framework\TestCase;
 use Zend\Diactoros\ServerRequestFactory;
 
-class ResourceServerTest extends \PHPUnit_Framework_TestCase
+class ResourceServerTest extends TestCase
 {
     public function testValidateAuthenticatedRequest()
     {
diff --git a/tests/ResponseTypes/BearerResponseTypeTest.php b/tests/ResponseTypes/BearerResponseTypeTest.php
index 7f710d92..daad734e 100644
--- a/tests/ResponseTypes/BearerResponseTypeTest.php
+++ b/tests/ResponseTypes/BearerResponseTypeTest.php
@@ -11,11 +11,12 @@ use LeagueTests\Stubs\AccessTokenEntity;
 use LeagueTests\Stubs\ClientEntity;
 use LeagueTests\Stubs\RefreshTokenEntity;
 use LeagueTests\Stubs\ScopeEntity;
+use PHPUnit\Framework\TestCase;
 use Psr\Http\Message\ResponseInterface;
 use Zend\Diactoros\Response;
 use Zend\Diactoros\ServerRequest;
 
-class BearerResponseTypeTest extends \PHPUnit_Framework_TestCase
+class BearerResponseTypeTest extends TestCase
 {
     public function testGenerateHttpResponse()
     {
diff --git a/tests/Stubs/CryptTraitStub.php b/tests/Stubs/CryptTraitStub.php
index a481a849..3fe02199 100644
--- a/tests/Stubs/CryptTraitStub.php
+++ b/tests/Stubs/CryptTraitStub.php
@@ -2,7 +2,6 @@
 
 namespace LeagueTests\Stubs;
 
-use League\OAuth2\Server\CryptKey;
 use League\OAuth2\Server\CryptTrait;
 
 class CryptTraitStub