diff --git a/Application/Controller/Admin/MailConfigCheck.php b/Application/Controller/Admin/MailConfigCheck.php
index 4d9e3bf..048c885 100644
--- a/Application/Controller/Admin/MailConfigCheck.php
+++ b/Application/Controller/Admin/MailConfigCheck.php
@@ -46,19 +46,19 @@ class MailConfigCheck extends AdminDetailsController
 
             Assert::lazy()
                 ->setExceptionClass(d3TranslatableLazyAssertionException::class)
-                ->that( $shop->getFieldData( 'oxsmtp' ), $lang->translateString('SHOP_MAIN_SMTPSERVER') )
-                ->notBlank( $lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET') )
-                ->regex( '/.*:(587|2525)$/m', $lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOPORT') )
-                ->that( $shop->getFieldData( 'oxsmtpuser' ), $lang->translateString('SHOP_MAIN_SMTPUSER') )
-                ->notBlank( $lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET') )
-                ->that( $shop->getFieldData( 'oxsmtppwd' ), $lang->translateString('SHOP_MAIN_SMTPPASSWORD') )
-                ->notBlank( $lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET') )
-                ->that( $shop->getFieldData( 'oxinfoemail' ), $lang->translateString('SHOP_MAIN_INFOEMAIL') )
-                ->email( $lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET') )
-                ->that( $shop->getFieldData( 'oxorderemail' ), $lang->translateString('SHOP_MAIN_ORDEREMAIL') )
-                ->email( $lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET') )
-                ->that( $shop->getFieldData( 'oxowneremail' ), $lang->translateString('SHOP_MAIN_OWNEREMAIL') )
-                ->email( $lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET') )
+                ->that($shop->getFieldData('oxsmtp'), $lang->translateString('SHOP_MAIN_SMTPSERVER'))
+                ->notBlank($lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET'))
+                ->regex('/.*:(587|2525)$/m', $lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOPORT'))
+                ->that($shop->getFieldData('oxsmtpuser'), $lang->translateString('SHOP_MAIN_SMTPUSER'))
+                ->notBlank($lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET'))
+                ->that($shop->getFieldData('oxsmtppwd'), $lang->translateString('SHOP_MAIN_SMTPPASSWORD'))
+                ->notBlank($lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET'))
+                ->that($shop->getFieldData('oxinfoemail'), $lang->translateString('SHOP_MAIN_INFOEMAIL'))
+                ->email($lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET'))
+                ->that($shop->getFieldData('oxorderemail'), $lang->translateString('SHOP_MAIN_ORDEREMAIL'))
+                ->email($lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET'))
+                ->that($shop->getFieldData('oxowneremail'), $lang->translateString('SHOP_MAIN_OWNEREMAIL'))
+                ->email($lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET'))
                 ->verifyNow();
         } catch (InvalidArgumentException $e) {
             Registry::getUtilsView()->addErrorToDisplay(nl2br($e->getMessage()));
@@ -73,13 +73,13 @@ class MailConfigCheck extends AdminDetailsController
     protected function getCurrentMailer()
     {
         try {
-            $mail = oxNew( Email::class );
-            $mail->setRecipient( $this->testMailAddress );
+            $mail = oxNew(Email::class);
+            $mail->setRecipient($this->testMailAddress);
             $mail->setBody('.');
             $mail->send();
             $this->addTplParam('mailer', $mail->getMailer());
-        } catch ( Exception $e) {
+        } catch (Exception $e) {
             Registry::getUtilsView()->addErrorToDisplay($e);
         }
     }
-}
\ No newline at end of file
+}
diff --git a/Application/Controller/Admin/MailTester.php b/Application/Controller/Admin/MailTester.php
index fb7fd24..3e93f4b 100644
--- a/Application/Controller/Admin/MailTester.php
+++ b/Application/Controller/Admin/MailTester.php
@@ -31,19 +31,19 @@ class MailTester extends AdminDetailsController
         try {
             $request = Registry::getRequest();
 
-            $from       = trim($request->getRequestEscapedParameter( 'from' ));
+            $from       = trim($request->getRequestEscapedParameter('from'));
             $this->addTplParam('sender', $from);
-            $to         = trim($request->getRequestEscapedParameter( 'to' ));
+            $to         = trim($request->getRequestEscapedParameter('to'));
             $this->addTplParam('recipient', $to);
-            $subject    = trim($request->getRequestEscapedParameter( 'subject' ));
+            $subject    = trim($request->getRequestEscapedParameter('subject'));
             $this->addTplParam('subject', $subject);
-            $body    = trim($request->getRequestEscapedParameter( 'body' ));
+            $body    = trim($request->getRequestEscapedParameter('body'));
             $this->addTplParam('body', $body);
 
             $this->assertContent();
 
-            $mail = oxNew( Email::class );
-            $mail->setFrom( $from );
+            $mail = oxNew(Email::class);
+            $mail->setFrom($from);
             $mail->sendEmail($to, $subject, $body);
             $this->addTplParam('success', true);
         } catch (\Exception $e) {
@@ -59,19 +59,19 @@ class MailTester extends AdminDetailsController
         Assert::lazy()
             ->setExceptionClass(d3TranslatableLazyAssertionException::class)
             ->that(
-                $request->getRequestEscapedParameter( 'from' ),
+                $request->getRequestEscapedParameter('from'),
                 $lang->translateString('D3_MAILCHECKER_SMTPCHECK_SENDER')
             )->email($lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET'))
             ->that(
-                $request->getRequestEscapedParameter( 'to' ),
+                $request->getRequestEscapedParameter('to'),
                 $lang->translateString('D3_MAILCHECKER_SMTPCHECK_RECIPIENT')
             )->email($lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET'))
             ->that(
-                $request->getRequestEscapedParameter( 'subject' ),
+                $request->getRequestEscapedParameter('subject'),
                 $lang->translateString('D3_MAILCHECKER_TESTMAIL_SUBJECT')
             )->notBlank($lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET'))
             ->that(
-                $request->getRequestEscapedParameter( 'body' ),
+                $request->getRequestEscapedParameter('body'),
                 $lang->translateString('D3_MAILCHECKER_TESTMAIL_BODY')
             )->notBlank($lang->translateString('D3_MAILCHECKER_ASSERTIONS_NOTSET'))
             ->verifyNow();
@@ -92,4 +92,4 @@ class MailTester extends AdminDetailsController
             )
         );
     }
-}
\ No newline at end of file
+}
diff --git a/Application/Controller/Admin/SmtpChecker.php b/Application/Controller/Admin/SmtpChecker.php
index 9c7c8ec..6e5a969 100644
--- a/Application/Controller/Admin/SmtpChecker.php
+++ b/Application/Controller/Admin/SmtpChecker.php
@@ -47,9 +47,9 @@ class SmtpChecker extends AdminDetailsController
         $activeShop = Registry::getConfig()->getActiveShop();
 
         if ($localHost = Registry::getRequest()->getRequestEscapedParameter('smtpHost')) {
-            list( 'host' => $shopHost, 'port' => $shopPort ) = parse_url( trim($localHost) );
+            ['host' => $shopHost, 'port' => $shopPort] = parse_url(trim($localHost));
         } else {
-            list( 'host' => $shopHost, 'port' => $shopPort ) = parse_url( trim($activeShop->getFieldData( 'oxsmtp' )) );
+            ['host' => $shopHost, 'port' => $shopPort] = parse_url(trim($activeShop->getFieldData('oxsmtp')));
         }
 
         $this->host = $shopHost;
@@ -123,7 +123,7 @@ class SmtpChecker extends AdminDetailsController
     {
         $this->action = __FUNCTION__;
         Assert::that(
-            ( $this->smtp = new Net_SMTP( $this->host, $this->port ) ),
+            ($this->smtp = new Net_SMTP($this->host, $this->port)),
             Registry::getLang()->translateString('D3_MAILCHECKER_SMTPCHECK_INSTANCE')
         )->isInstanceOf(
             Net_SMTP::class,
@@ -179,7 +179,7 @@ class SmtpChecker extends AdminDetailsController
     {
         $this->action = __FUNCTION__;
         Assert::that(
-            $this->smtp->rcptTo( $this->to),
+            $this->smtp->rcptTo($this->to),
             Registry::getLang()->translateString('D3_MAILCHECKER_SMTPCHECK_RECIPIENT')
         )->notIsInstanceOf(
             PEAR_Error::class,
@@ -198,7 +198,7 @@ class SmtpChecker extends AdminDetailsController
         $subj = "Subject: Test Message\n";
         $body = "Body Line 1\nBody Line 2";
         Assert::that(
-            $this->smtp->data( $subj . "\r\n" . $body),
+            $this->smtp->data($subj . "\r\n" . $body),
             Registry::getLang()->translateString('D3_MAILCHECKER_SMTPCHECK_TRANSMIT')
         )->notIsInstanceOf(
             PEAR_Error::class,
@@ -236,4 +236,4 @@ class SmtpChecker extends AdminDetailsController
 
         return null;
     }
-}
\ No newline at end of file
+}
diff --git a/Application/Controller/Admin/SpfChecker.php b/Application/Controller/Admin/SpfChecker.php
index 7abeac6..798ac38 100644
--- a/Application/Controller/Admin/SpfChecker.php
+++ b/Application/Controller/Admin/SpfChecker.php
@@ -41,7 +41,7 @@ class SpfChecker extends AdminDetailsController
         $mailDomains = $this->getMailDomains();
         array_walk(
             $mailDomains,
-            function($domain) use (&$result) {
+            function ($domain) use (&$result) {
                 $this->checkSpfByDomain($domain, $result);
             }
         );
@@ -58,15 +58,15 @@ class SpfChecker extends AdminDetailsController
             array_filter(
                 array_unique(
                     array_map(
-                        function($mailAddress) {
+                        function ($mailAddress) {
                             $mailAddress = trim($mailAddress);
                             try {
-                                if ( ! strstr( $mailAddress, '@' ) ) {
-                                    throw oxNew( InvalidArgumentException::class );
+                                if (! strstr($mailAddress, '@')) {
+                                    throw oxNew(InvalidArgumentException::class);
                                 }
-                                $addressChunks = explode( '@', $mailAddress );
+                                $addressChunks = explode('@', $mailAddress);
 
-                                return array_pop( $addressChunks );
+                                return array_pop($addressChunks);
                             } catch (InvalidArgumentException $e) {
                                 return '';
                             }
@@ -79,7 +79,6 @@ class SpfChecker extends AdminDetailsController
                     )
                 )
             );
-
     }
 
     protected function checkSpfByDomain($domain, &$summarize)
@@ -120,4 +119,4 @@ class SpfChecker extends AdminDetailsController
                 return 'danger';
         }
     }
-}
\ No newline at end of file
+}
diff --git a/Application/Model/Exception/d3TranslatableLazyAssertionException.php b/Application/Model/Exception/d3TranslatableLazyAssertionException.php
index 98afa37..c8ce644 100644
--- a/Application/Model/Exception/d3TranslatableLazyAssertionException.php
+++ b/Application/Model/Exception/d3TranslatableLazyAssertionException.php
@@ -23,13 +23,13 @@ class d3TranslatableLazyAssertionException extends LazyAssertionException
     public static function fromErrors(array $errors): LazyAssertionException
     {
         $text = Registry::getLang()->translateString('D3_MAILCHECKER_ASSERTIONS_FAILED');
-        $message = sprintf( $text, count( $errors ) ) . "\n";
+        $message = sprintf($text, count($errors)) . "\n";
 
         $i = 1;
         foreach ($errors as $error) {
-            $message .= sprintf( "%d) %s: %s\n", $i ++, $error->getPropertyPath(), $error->getMessage() );
+            $message .= sprintf("%d) %s: %s\n", $i ++, $error->getPropertyPath(), $error->getMessage());
         }
 
         return new LazyAssertionException($message, $errors);
     }
-}
\ No newline at end of file
+}
diff --git a/Application/Model/SpfResult.php b/Application/Model/SpfResult.php
index 0ec38d6..6cd9b8d 100644
--- a/Application/Model/SpfResult.php
+++ b/Application/Model/SpfResult.php
@@ -14,11 +14,12 @@
 declare(strict_types=1);
 
 namespace D3\MailConfigChecker\Application\Model;
+
 class SpfResult
 {
-    const SET        = 'set';
-    const MISSING   = 'missing';
-    const ERROR     = 'error';
+    public const SET        = 'set';
+    public const MISSING   = 'missing';
+    public const ERROR     = 'error';
 
     protected $status;
     protected $record;
@@ -38,4 +39,4 @@ class SpfResult
     {
         return $this->record;
     }
-}
\ No newline at end of file
+}