diff --git a/.php-cs-fixer.php b/.php-cs-fixer.php
new file mode 100644
index 0000000..9c1c04b
--- /dev/null
+++ b/.php-cs-fixer.php
@@ -0,0 +1,34 @@
+<?php
+
+$finder = (new PhpCsFixer\Finder())
+    ->in(__DIR__)
+;
+
+$header = <<<EOF
+Copyright (c) D3 Data Development (Inh. Thomas Dartsch)
+
+For the full copyright and license information, please view
+the LICENSE file that was distributed with this source code.
+
+https://www.d3data.de
+
+@copyright (C) D3 Data Development (Inh. Thomas Dartsch)
+@author    D3 Data Development - Daniel Seifert <info@shopmodule.com>
+@link      https://www.oxidmodule.com
+EOF;
+
+$config = new PhpCsFixer\Config();
+return $config->setRules([
+    '@PHP80Migration' => true,
+    '@PSR12' => true,
+    'header_comment' => [
+        'comment_type' => 'PHPDoc',
+        'header' => $header,
+        'location' => 'after_open',
+        'separate' => 'both',
+    ],
+    'php_unit_test_class_requires_covers' => true,
+    'doctrine_annotation_indentation' => true,
+])
+    ->setFinder($finder)
+;
\ No newline at end of file
diff --git a/composer.json b/composer.json
index 0f3f30d..ddb662f 100644
--- a/composer.json
+++ b/composer.json
@@ -16,7 +16,7 @@
     }
   ],
   "require": {
-    "php": ">=8.0",
+    "php": "^8.0",
     "composer/composer": "^2.7.1",
     "doctrine/collections": "^1.8.0",
     "guzzlehttp/guzzle": "~7.0",
@@ -26,12 +26,23 @@
     "phpunit/phpunit": "^9.3",
     "overtrue/phplint": "^1.2",
     "squizlabs/php_codesniffer": "3.*",
-    "phpstan/phpstan": "^1.9"
+    "phpstan/phpstan": "^2.0",
+    "friendsofphp/php-cs-fixer": "^3.65"
   },
   "autoload": {
     "psr-4": {
       "D3\\KlicktippPhpClient\\": "src/"
     }
+  },
+  "autoload-dev": {
+    "psr-4": {
+      "D3\\KlicktippPhpClient\\tests\\": "tests/"
+    }
+  },
+  "scripts": {
+    "test": "./vendor/bin/phpunit --no-coverage",
+    "check-style": "./vendor/bin/php-cs-fixer fix --verbose --dry-run",
+    "fix-style": "./vendor/bin/php-cs-fixer fix --verbose",
+    "check-code": "./vendor/bin/phpstan analyse -c phpstan.neon --no-progress --ansi"
   }
 }
-
diff --git a/phpstan.neon b/phpstan.neon
new file mode 100644
index 0000000..1fb084b
--- /dev/null
+++ b/phpstan.neon
@@ -0,0 +1,5 @@
+parameters:
+  paths:
+    - src
+  level: 10
+  phpVersion: 80000
\ No newline at end of file
diff --git a/phpunit.xml b/phpunit.xml
new file mode 100644
index 0000000..ddff8e0
--- /dev/null
+++ b/phpunit.xml
@@ -0,0 +1,20 @@
+<?xml version="1.0"?>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         bootstrap="vendor/autoload.php"
+         convertErrorsToExceptions="true"
+         convertNoticesToExceptions="true"
+         convertWarningsToExceptions="true"
+         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.3/phpunit.xsd">
+    <coverage>
+        <include>
+            <directory suffix=".php">src</directory>
+        </include>
+        <report>
+            <clover outputFile="build/logs/clover.xml"/>
+        </report>
+    </coverage>
+    <testsuite name="KlicktippPhpClient">
+        <directory>./tests</directory>
+    </testsuite>
+    <logging/>
+</phpunit>