diff --git a/Classes/Domain/Model/JobApplication.php b/Classes/Domain/Model/JobApplication.php
index 50eae3af088a18b82bd865e40cfe61e08ae4a483..9b81d5bc188b43fb0306bc25e88cfd210797dab4 100644
--- a/Classes/Domain/Model/JobApplication.php
+++ b/Classes/Domain/Model/JobApplication.php
@@ -74,6 +74,7 @@ class JobApplication extends AbstractEntity {
 
 	/**
 	 * @var string $zip
+	 * @validate NotEmpty
 	 */
 	protected $zip = '';
 
@@ -97,6 +98,7 @@ class JobApplication extends AbstractEntity {
 
 	/**
 	 * @var int $birthDate
+	 * @validate NotEmpty
 	 */
 	protected $birthDate = '';
 
@@ -119,16 +121,19 @@ class JobApplication extends AbstractEntity {
 
 	/**
 	 * @var \TYPO3\CMS\Extbase\Persistence\ObjectStorage<\TYPO3\CMS\Extbase\Domain\Model\FileReference> $coverLetter
+	 * @validate NotEmpty
 	 */
 	protected $coverLetter;
 
 	/**
 	 * @var \TYPO3\CMS\Extbase\Persistence\ObjectStorage<\TYPO3\CMS\Extbase\Domain\Model\FileReference> $cv
+	 * @validate NotEmpty
 	 */
 	protected $cv;
 
 	/**
 	 * @var \TYPO3\CMS\Extbase\Persistence\ObjectStorage<\TYPO3\CMS\Extbase\Domain\Model\FileReference> $certificates
+	 * @validate NotEmpty
 	 */
 	protected $certificates;
 
@@ -293,7 +298,7 @@ class JobApplication extends AbstractEntity {
 	/**
 	 * @param int $birthDate
 	 */
-	public function setBirthDate(string $birthDate) {
+	public function setBirthDate($birthDate) {
 		$this->birthDate = (int) $birthDate;
 	}