diff --git a/composer.json b/composer.json
index 4742d6d..581b86d 100644
--- a/composer.json
+++ b/composer.json
@@ -20,9 +20,8 @@
         "symfony/console": "~2.7|~3.0|~4.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "^8.4",
-        "pluswerk/grumphp-config": "^3.0",
-        "dg/bypass-finals": "^1.1"
+        "phpunit/phpunit": "8.4.*",
+        "pluswerk/grumphp-config": "^3.0"
     },
     "autoload": {
         "psr-4": {
diff --git a/phpunit.xml b/phpunit.xml
index ede97d2..fd4f7a0 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -8,9 +8,6 @@
          beStrictAboutOutputDuringTests="true"
          beStrictAboutTodoAnnotatedTests="true"
          verbose="true">
-    <extensions>
-        <extension class="Pluswerk\TypoScriptAutoFixer\Hook\BypassFinalHook"/>
-    </extensions>
     <testsuites>
         <testsuite name="default">
             <directory suffix="Test.php">tests</directory>
diff --git a/src/Adapter/Configuration/Reader/YamlConfigurationReader.php b/src/Adapter/Configuration/Reader/YamlConfigurationReader.php
index 56d836f..acf8a75 100644
--- a/src/Adapter/Configuration/Reader/YamlConfigurationReader.php
+++ b/src/Adapter/Configuration/Reader/YamlConfigurationReader.php
@@ -6,7 +6,7 @@
 use Pluswerk\TypoScriptAutoFixer\Exception\FailedReadConfigurationException;
 use Symfony\Component\Yaml\Yaml;
 
-class YamlConfigurationReader extends AbstractConfigurationReader
+final class YamlConfigurationReader extends AbstractConfigurationReader
 {
     public function __construct(string $filePath = '')
     {
diff --git a/src/Adapter/Linter.php b/src/Adapter/Linter.php
index 397bc81..0f208e6 100644
--- a/src/Adapter/Linter.php
+++ b/src/Adapter/Linter.php
@@ -12,7 +12,7 @@
 use Pluswerk\TypoScriptAutoFixer\Issue\AbstractIssue;
 use Pluswerk\TypoScriptAutoFixer\Issue\IssueCollection;
 
-final class Linter
+class Linter
 {
     /**
      * @var Configuration
diff --git a/src/File.php b/src/File.php
index 337ec20..942c038 100644
--- a/src/File.php
+++ b/src/File.php
@@ -7,7 +7,7 @@
 use Pluswerk\TypoScriptAutoFixer\Exception\WriteFileFailedException;
 use Pluswerk\TypoScriptAutoFixer\Issue\IssueCollection;
 
-final class File extends \SplFileInfo
+class File extends \SplFileInfo
 {
     /**
      * @var IssueCollection
diff --git a/src/FileBuilder.php b/src/FileBuilder.php
index a0b6695..8a2bc93 100644
--- a/src/FileBuilder.php
+++ b/src/FileBuilder.php
@@ -5,7 +5,7 @@
 
 use Pluswerk\TypoScriptAutoFixer\Adapter\Linter;
 
-final class FileBuilder
+class FileBuilder
 {
     /**
      * @var Linter
diff --git a/src/Fixer/FixerFactory.php b/src/Fixer/FixerFactory.php
index 302a031..d275c56 100644
--- a/src/Fixer/FixerFactory.php
+++ b/src/Fixer/FixerFactory.php
@@ -14,7 +14,7 @@
 use Pluswerk\TypoScriptAutoFixer\Issue\NestingConsistencyIssue;
 use Pluswerk\TypoScriptAutoFixer\Issue\OperatorWhitespaceIssue;
 
-final class FixerFactory
+class FixerFactory
 {
     /**
      * @param AbstractIssue $issue
diff --git a/src/Fixer/Indentation/LineFixer.php b/src/Fixer/Indentation/LineFixer.php
index ac9a8b4..722135e 100644
--- a/src/Fixer/Indentation/LineFixer.php
+++ b/src/Fixer/Indentation/LineFixer.php
@@ -3,7 +3,7 @@
 
 namespace Pluswerk\TypoScriptAutoFixer\Fixer\Indentation;
 
-final class LineFixer
+class LineFixer
 {
     /**
      * @param $line
diff --git a/src/Fixer/NestingConsistency/NodeCollectionBuilder.php b/src/Fixer/NestingConsistency/NodeCollectionBuilder.php
index a078bcf..b6772ef 100644
--- a/src/Fixer/NestingConsistency/NodeCollectionBuilder.php
+++ b/src/Fixer/NestingConsistency/NodeCollectionBuilder.php
@@ -3,7 +3,7 @@
 
 namespace Pluswerk\TypoScriptAutoFixer\Fixer\NestingConsistency;
 
-final class NodeCollectionBuilder
+class NodeCollectionBuilder
 {
     /**
      * @param NodeCollection $nodesA
diff --git a/src/Fixer/OperatorWhitespace/LineFixer.php b/src/Fixer/OperatorWhitespace/LineFixer.php
index c9326c9..ae1ffaa 100644
--- a/src/Fixer/OperatorWhitespace/LineFixer.php
+++ b/src/Fixer/OperatorWhitespace/LineFixer.php
@@ -3,7 +3,7 @@
 
 namespace Pluswerk\TypoScriptAutoFixer\Fixer\OperatorWhitespace;
 
-final class LineFixer
+class LineFixer
 {
     /**
      * @param string $line
diff --git a/src/Hook/BypassFinalHook.php b/src/Hook/BypassFinalHook.php
deleted file mode 100644
index 48a8562..0000000
--- a/src/Hook/BypassFinalHook.php
+++ /dev/null
@@ -1,20 +0,0 @@
-<?php
-declare(strict_types=1);
-
-namespace Pluswerk\TypoScriptAutoFixer\Hook;
-
-use DG\BypassFinals;
-use PHPUnit\Runner\BeforeTestHook;
-
-/**
- * Class BypassFinalHook
- * @package Pluswerk\TypoScriptLinter\Hook
- * @codeCoverageIgnore
- */
-final class BypassFinalHook implements BeforeTestHook
-{
-    public function executeBeforeTest(string $test): void
-    {
-        BypassFinals::enable();
-    }
-}
diff --git a/src/Issue/IssueCollection.php b/src/Issue/IssueCollection.php
index a3d9376..d2bceab 100644
--- a/src/Issue/IssueCollection.php
+++ b/src/Issue/IssueCollection.php
@@ -6,7 +6,7 @@
 use Helmich\TypoScriptLint\Linter\Report\Issue;
 use Pluswerk\TypoScriptAutoFixer\Issue\AbstractIssue;
 
-final class IssueCollection implements \Countable, \Iterator
+class IssueCollection implements \Countable, \Iterator
 {
     /**
      * @var AbstractIssue[]