diff --git a/Classes/Service/RegisterInterface.php b/Classes/Service/RegisterInterface.php
index 1efb57f91e53479034f11c8d58b2ccd76d7dbcb2..5e28367fb5679fb690374b63fcb73a6b105e6cc8 100644
--- a/Classes/Service/RegisterInterface.php
+++ b/Classes/Service/RegisterInterface.php
@@ -48,5 +48,3 @@ interface RegisterInterface {
 	 */
 	public function registerTemplate();
 }
-
-?>
\ No newline at end of file
diff --git a/Classes/Service/RegisterService.php b/Classes/Service/RegisterService.php
index a341bb83f88e56a16722fde446672bd2ab189b3c..8170bbe2cc81f678094cc3d409dc8d7b01d3414a 100644
--- a/Classes/Service/RegisterService.php
+++ b/Classes/Service/RegisterService.php
@@ -39,10 +39,10 @@ use TYPO3\CMS\Extbase\Object\ObjectManager;
  * Provides an api for registering your mail templates
  */
 class RegisterService implements \TYPO3\CMS\Core\SingletonInterface {
-	const CACHE_NAME = 'sg_mail_registerArrayCache';
-	const CACHE_LIFETIME_IN_SECONDS = 86400;
-	const DEFAULT_TEMPLATE_PATH = 'Resources/Private/Templates/SgMail/';
-	const CONFIG_PATH = 'Configuration/MailTemplates/Forms';
+	public const CACHE_NAME = 'sg_mail_registerArrayCache';
+	public const CACHE_LIFETIME_IN_SECONDS = 86400;
+	public const DEFAULT_TEMPLATE_PATH = 'Resources/Private/Templates/SgMail/';
+	public const CONFIG_PATH = 'Configuration/MailTemplates/Forms';
 
 	/**
 	 * contains the actual registration data
@@ -141,7 +141,7 @@ class RegisterService implements \TYPO3\CMS\Core\SingletonInterface {
 					continue;
 				}
 
-				$this->writeRegisterArrayEntry($extensionKey, $templateKey, $configArray, FALSE);
+				$this->writeRegisterArrayEntry($extensionKey, $templateKey, $configArray);
 			}
 		}
 
@@ -157,7 +157,7 @@ class RegisterService implements \TYPO3\CMS\Core\SingletonInterface {
 	 */
 	private function writeRegisterArrayEntry(
 		$extensionKey, $templateKey, array $configArray
-	) {
+	): void {
 		// template_path means where to find the mail body content (usually it's set directly in the registration
 		// as template_content)
 		$templatePath = '';
@@ -213,7 +213,7 @@ class RegisterService implements \TYPO3\CMS\Core\SingletonInterface {
 	 *
 	 * @throws \TYPO3\CMS\Core\Cache\Exception\NoSuchCacheException
 	 */
-	public function clearCaches() {
+	public function clearCaches(): void {
 		$objectManager = GeneralUtility::makeInstance(ObjectManager::class);
 		$cacheManager = $objectManager->get(CacheManager::class);
 
@@ -291,7 +291,7 @@ class RegisterService implements \TYPO3\CMS\Core\SingletonInterface {
 	 * @param string $markerName
 	 * @return string
 	 */
-	public static function normalizeFormFieldMarkerName($markerName = '') {
+	public static function normalizeFormFieldMarkerName($markerName = ''): string {
 		return \preg_replace('/[^a-z0-9\-_]/i', '', $markerName);
 	}
 
@@ -299,7 +299,7 @@ class RegisterService implements \TYPO3\CMS\Core\SingletonInterface {
 	 * Register the caches for the RegisterService
 	 * This method is for usage in ext_localconf.php to register the cache configuration
 	 */
-	public function registerCache() {
+	public function registerCache(): void {
 		$cacheConfigurations = $GLOBALS['TYPO3_CONF_VARS']['SYS']['caching']['cacheConfigurations'];
 		if (!isset($cacheConfigurations[self::CACHE_NAME])) {
 			$cacheConfigurations[self::CACHE_NAME] = [
diff --git a/Classes/Session/PhpSession.php b/Classes/Session/PhpSession.php
index 501f603010484e3f030faec56e2f2dfa4417c4d8..331659ec62473f43fe803e4552f81ca1a8ff16cb 100644
--- a/Classes/Session/PhpSession.php
+++ b/Classes/Session/PhpSession.php
@@ -49,7 +49,7 @@ class PhpSession implements SingletonInterface {
 	 * @param string $sessionKey
 	 * @return void
 	 */
-	public function setSessionKey($sessionKey) {
+	public function setSessionKey($sessionKey): void {
 		$this->sessionKey = $sessionKey;
 	}
 
@@ -58,7 +58,7 @@ class PhpSession implements SingletonInterface {
 	 *
 	 * @return string
 	 */
-	public function getSessionKey() {
+	public function getSessionKey(): string {
 		return $this->sessionKey;
 	}
 
@@ -68,7 +68,7 @@ class PhpSession implements SingletonInterface {
 	 * @param mixed $data
 	 * @return void
 	 */
-	public function exchangeData($data) {
+	public function exchangeData($data): void {
 		$this->destroy();
 		$_SESSION[$this->sessionKey] = $data;
 	}
@@ -89,7 +89,7 @@ class PhpSession implements SingletonInterface {
 	 * @param mixed $data
 	 * @return void
 	 */
-	public function setDataByKey($key, $data) {
+	public function setDataByKey($key, $data): void {
 		$_SESSION[$this->sessionKey][$key] = $data;
 	}
 
@@ -109,7 +109,7 @@ class PhpSession implements SingletonInterface {
 	 * @param string $key
 	 * @return void
 	 */
-	public function unsetDataByKey($key) {
+	public function unsetDataByKey($key): void {
 		unset($_SESSION[$this->sessionKey][$key]);
 	}
 
@@ -118,7 +118,7 @@ class PhpSession implements SingletonInterface {
 	 *
 	 * @return void
 	 */
-	public function destroy() {
+	public function destroy(): void {
 		unset($_SESSION[$this->sessionKey]);
 	}
 }
diff --git a/Classes/UserFunc/ExtensionConfiguration.php b/Classes/UserFunc/ExtensionConfiguration.php
index 9825eea56e6e5bfa5c3752473d92d1513a0dceb0..ee7ef0bae7b962e926f937c1d5f5a142ffff7a60 100644
--- a/Classes/UserFunc/ExtensionConfiguration.php
+++ b/Classes/UserFunc/ExtensionConfiguration.php
@@ -27,7 +27,6 @@ namespace SGalinski\SgMail\UserFunc;
  ***************************************************************/
 
 use SGalinski\SgMail\Service\RegisterService;
-use TYPO3\CMS\Core\Configuration\ConfigurationManager;
 use TYPO3\CMS\Core\Utility\ExtensionManagementUtility;
 use TYPO3\CMS\Core\Utility\GeneralUtility;