diff --git a/README.md b/README.md
index b6fea44..a84bb1a 100644
--- a/README.md
+++ b/README.md
@@ -47,7 +47,7 @@ See [OS2Web git name convention](https://github.com/OS2Web/docs#git-guideline)
 // CVR lookup
 /** @var \Drupal\os2web_datalookup\Plugin\DataLookupManager $pluginManager */
 $pluginManager = \Drupal::service('plugin.manager.os2web_datalookup');
-/** @var \Drupal\os2web_datalookup\Plugin\os2web\DataLookup\DataLookupInterfaceCompany $cvrPlugin */
+/** @var \Drupal\os2web_datalookup\Plugin\os2web\DataLookup\DataLookupCompanyInterface $cvrPlugin */
 $cvrPlugin = $pluginManager->createDefaultInstanceByGroup('cvr_lookup');
 
 if ($cvrPlugin->isReady()) {
@@ -57,7 +57,7 @@ if ($cvrPlugin->isReady()) {
 // CPR lookup.
 /** @var \Drupal\os2web_datalookup\Plugin\DataLookupManager $pluginManager */
 $pluginManager = \Drupal::service('plugin.manager.os2web_datalookup');
-/** @var \Drupal\os2web_datalookup\Plugin\os2web\DataLookup\DataLookupInterfaceCpr $cprPlugin */
+/** @var \Drupal\os2web_datalookup\Plugin\os2web\DataLookup\DataLookupCprInterface $cprPlugin */
 $cprPlugin = $pluginManager->createDefaultInstanceByGroup('cpr_lookup');
 
 if ($cprPlugin->isReady()) {
diff --git a/os2web_datalookup.install b/os2web_datalookup.install
index 2ef175e..55bc8c5 100644
--- a/os2web_datalookup.install
+++ b/os2web_datalookup.install
@@ -1,11 +1,16 @@
 <?php
 
+/**
+ * @file
+ * Install, uninstall and update hooks for the module.
+ */
+
 use Drupal\os2web_datalookup\Form\DataLookupPluginGroupSettingsForm;
 
 /**
  * Setting "serviceplatformen_cpr_extended" as default CPR lookup plugin.
  */
-function os2web_datalookup_update_9001() {
+function os2web_datalookup_update_9001(): void {
   $config = \Drupal::service('config.factory')->getEditable(DataLookupPluginGroupSettingsForm::$configName);
   $config->set("cpr_lookup.default_plugin", 'serviceplatformen_cpr_extended');
   $config->save();
@@ -14,7 +19,7 @@ function os2web_datalookup_update_9001() {
 /**
  * Setting "datafordeler_cvr" as default CVR lookup plugin.
  */
-function os2web_datalookup_update_9002() {
+function os2web_datalookup_update_9002(): void {
   $config = \Drupal::service('config.factory')->getEditable(DataLookupPluginGroupSettingsForm::$configName);
   $config->set("cvr_lookup.default_plugin", 'datafordeler_cvr');
   $config->save();
@@ -23,7 +28,7 @@ function os2web_datalookup_update_9002() {
 /**
  * Setting "datafordeler_pnumber" as default P-Number lookup plugin.
  */
-function os2web_datalookup_update_9003() {
+function os2web_datalookup_update_9003(): void {
   $config = \Drupal::service('config.factory')->getEditable(DataLookupPluginGroupSettingsForm::$configName);
   $config->set("pnumber_lookup.default_plugin", 'datafordeler_pnumber');
   $config->save();
diff --git a/src/Annotation/DataLookup.php b/src/Annotation/DataLookup.php
index 807383f..1d00608 100644
--- a/src/Annotation/DataLookup.php
+++ b/src/Annotation/DataLookup.php
@@ -3,6 +3,7 @@
 namespace Drupal\os2web_datalookup\Annotation;
 
 use Drupal\Component\Annotation\Plugin;
+use Drupal\Core\Annotation\Translation;
 
 /**
  * Defines a AuthProvider annotation object.
@@ -22,7 +23,7 @@ class DataLookup extends Plugin {
    *
    * @var string
    */
-  public $id;
+  public string $id;
 
   /**
    * The human-readable name of the consent storage.
@@ -31,24 +32,24 @@ class DataLookup extends Plugin {
    *
    * @ingroup plugin_translatable
    */
-  public $label;
+  public Translation $label;
 
   /**
    * A brief description of the consent storage.
    *
    * This will be shown when adding or configuring this consent storage.
    *
-   * @var \Drupal\Core\Annotation\Translation
+   * @var \Drupal\Core\Annotation\Translation|string
    *
    * @ingroup plugin_translatable
    */
-  public $description = '';
+  public Translation|string $description = '';
 
   /**
-   * Group of the plugin lookup plugin.
+   * Group of the plugin lookup plugins.
    *
    * @var string
    */
-  public $group = '';
+  public string $group = '';
 
 }
diff --git a/src/Controller/DatalookupController.php b/src/Controller/DatalookupController.php
index 5550f9f..a778eb7 100644
--- a/src/Controller/DatalookupController.php
+++ b/src/Controller/DatalookupController.php
@@ -5,11 +5,10 @@
 use Drupal\Component\Plugin\PluginManagerInterface;
 use Drupal\Core\Controller\ControllerBase;
 use Drupal\Core\Link;
-use Drupal\os2web_datalookup\Plugin\os2web\DataLookup\DataLookupInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
- * Class DatalookupController.
+ * Data lookup controller.
  *
  * @package Drupal\os2web_datalookup\Controller
  */
@@ -20,10 +19,13 @@ class DatalookupController extends ControllerBase {
    *
    * @var \Drupal\Component\Plugin\PluginManagerInterface
    */
-  protected $manager;
+  protected PluginManagerInterface $manager;
 
   /**
-   * {@inheritdoc}
+   * Default constructor.
+   *
+   * @param \Drupal\Component\Plugin\PluginManagerInterface $manager
+   *   The plugin manger.
    */
   public function __construct(PluginManagerInterface $manager) {
     $this->manager = $manager;
@@ -40,8 +42,13 @@ public static function create(ContainerInterface $container) {
 
   /**
    * Status list callback.
+   *
+   * @return array<string, mixed>
+   *   An render array.
+   *
+   * @throws \Drupal\Component\Plugin\Exception\PluginException
    */
-  public function statusList() {
+  public function statusList(): array {
     $headers = [
       'title' => $this
         ->t('Title'),
@@ -55,7 +62,7 @@ public function statusList() {
 
     $rows = [];
     foreach ($this->manager->getDefinitions() as $id => $plugin_definition) {
-      /** @var DataLookupInterface $plugin */
+      /** @var \Drupal\os2web_datalookup\Plugin\os2web\DataLookup\DataLookupInterface $plugin */
       $plugin = $this->manager->createInstance($id);
       $status = $plugin->getStatus();
       $rows[$id] = [
diff --git a/src/Form/DataLookupPluginGroupSettingsForm.php b/src/Form/DataLookupPluginGroupSettingsForm.php
index 057accc..11ef7f2 100644
--- a/src/Form/DataLookupPluginGroupSettingsForm.php
+++ b/src/Form/DataLookupPluginGroupSettingsForm.php
@@ -6,6 +6,7 @@
 use Drupal\Core\Form\ConfigFormBase;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Link;
+use Drupal\os2web_datalookup\Plugin\DataLookupManager;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
@@ -18,16 +19,20 @@ class DataLookupPluginGroupSettingsForm extends ConfigFormBase {
    *
    * @var string
    */
-  public static $configName = 'os2web_datalookup.groups.settings';
+  public static string $configName = 'os2web_datalookup.groups.settings';
 
-  /** @var \Drupal\os2web_datalookup\Plugin\DataLookupManager */
-  protected $dataLookupManager;
+  /**
+   * Data lookup manager.
+   *
+   * @var \Drupal\os2web_datalookup\Plugin\DataLookupManager
+   */
+  protected DataLookupManager $dataLookupManager;
 
   /**
    * Constructs a new DataLookupPluginGroupSettingsForm object.
    *
-   * @param \Drupal\os2web_datalookup\Plugin\DataLookupManager
-   *   Datalookup manager.
+   * @param \Drupal\os2web_datalookup\Plugin\DataLookupManager $dataLookupManager
+   *   Data lookup manager.
    */
   public function __construct(PluginManagerInterface $dataLookupManager) {
     $this->dataLookupManager = $dataLookupManager;
@@ -36,7 +41,7 @@ public function __construct(PluginManagerInterface $dataLookupManager) {
   /**
    * {@inheritdoc}
    */
-  public static function create(ContainerInterface $container) {
+  public static function create(ContainerInterface $container): static {
     return new static(
       $container->get('plugin.manager.os2web_datalookup')
     );
@@ -52,7 +57,7 @@ public function getFormId() {
   /**
    * {@inheritdoc}
    */
-  protected function getEditableConfigNames() {
+  protected function getEditableConfigNames(): array {
     return [DataLookupPluginGroupSettingsForm::$configName];
   }
 
@@ -69,7 +74,7 @@ protected function getGroupIdFromRequest() {
   /**
    * {@inheritdoc}
    */
-  public function buildForm(array $form, FormStateInterface $form_state) {
+  public function buildForm(array $form, FormStateInterface $form_state): array {
     $group_id = $this->getGroupIdFromRequest();
 
     $plugin_definitions = $this->dataLookupManager->getDefinitionsByGroup($group_id);
@@ -114,7 +119,7 @@ public function buildForm(array $form, FormStateInterface $form_state) {
   /**
    * {@inheritdoc}
    */
-  public function submitForm(array &$form, FormStateInterface $form_state) {
+  public function submitForm(array &$form, FormStateInterface $form_state): void {
     $group_id = $this->getGroupIdFromRequest();
 
     $config = $this->config(DataLookupPluginGroupSettingsForm::$configName);
diff --git a/src/Form/DataLookupPluginSettingsForm.php b/src/Form/DataLookupPluginSettingsForm.php
index e36ace3..47be3d8 100644
--- a/src/Form/DataLookupPluginSettingsForm.php
+++ b/src/Form/DataLookupPluginSettingsForm.php
@@ -22,7 +22,7 @@ public function __construct(ConfigFactoryInterface $config_factory, PluginManage
   /**
    * {@inheritdoc}
    */
-  public static function create(ContainerInterface $container) {
+  public static function create(ContainerInterface $container):static {
     return new static(
       $container->get('config.factory'),
       $container->get('plugin.manager.os2web_datalookup')
@@ -32,7 +32,7 @@ public static function create(ContainerInterface $container) {
   /**
    * {@inheritdoc}
    */
-  public static function getConfigName() {
+  public static function getConfigName(): string {
     return 'os2web_datalookup';
   }
 
diff --git a/src/Form/PluginSettingsFormBase.php b/src/Form/PluginSettingsFormBase.php
index 2927a55..e4874e6 100644
--- a/src/Form/PluginSettingsFormBase.php
+++ b/src/Form/PluginSettingsFormBase.php
@@ -7,6 +7,7 @@
  * Abstract class for PluginSettingsForm implementation.
  */
 
+use Drupal\Component\Plugin\PluginManagerInterface;
 use Drupal\Core\Form\ConfigFormBase;
 use Drupal\Core\Form\FormStateInterface;
 
@@ -20,36 +21,37 @@ abstract class PluginSettingsFormBase extends ConfigFormBase implements PluginSe
    *
    * @var \Drupal\Component\Plugin\PluginManagerInterface
    */
-  protected $manager;
+  protected PluginManagerInterface $manager;
 
   /**
    * {@inheritdoc}
    */
-  protected function getEditableConfigNames() {
+  protected function getEditableConfigNames(): array {
     return [$this->getConfigId()];
   }
 
   /**
    * {@inheritdoc}
    */
-  public function getFormId() {
+  public function getFormId(): string {
     return $this->getConfigName() . '_settings_form_' . $this->getPluginIdFromRequest();
   }
 
   /**
    * {@inheritdoc}
    */
-  public function buildForm(array $form, FormStateInterface $form_state) {
+  public function buildForm(array $form, FormStateInterface $form_state): array {
     $plugin_id = $this->getPluginIdFromRequest();
     $instance = $this->getPluginInstance($plugin_id);
     $form = $instance->buildConfigurationForm($form, $form_state);
+
     return parent::buildForm($form, $form_state);
   }
 
   /**
    * {@inheritdoc}
    */
-  public function validateForm(array &$form, FormStateInterface $form_state) {
+  public function validateForm(array &$form, FormStateInterface $form_state): void {
     $plugin_id = $this->getPluginIdFromRequest();
     $instance = $this->getPluginInstance($plugin_id);
     $instance->validateConfigurationForm($form, $form_state);
@@ -58,7 +60,7 @@ public function validateForm(array &$form, FormStateInterface $form_state) {
   /**
    * {@inheritdoc}
    */
-  public function submitForm(array &$form, FormStateInterface $form_state) {
+  public function submitForm(array &$form, FormStateInterface $form_state): void {
     $plugin_id = $this->getPluginIdFromRequest();
     $instance = $this->getPluginInstance($plugin_id);
     $instance->submitConfigurationForm($form, $form_state);
@@ -77,6 +79,7 @@ public function submitForm(array &$form, FormStateInterface $form_state) {
    */
   protected function getPluginIdFromRequest() {
     $request = $this->getRequest();
+
     return $request->get('_plugin_id');
   }
 
@@ -89,11 +92,12 @@ protected function getPluginIdFromRequest() {
    * @return object
    *   Plugin instance.
    *
-   * @throws PluginException
+   * @throws \Drupal\Component\Plugin\Exception\PluginException
    */
-  public function getPluginInstance($plugin_id) {
+  public function getPluginInstance($plugin_id): object {
     $configuration = $this->config($this->getConfigId())->get();
     $instance = $this->manager->createInstance($plugin_id, $configuration);
+
     return $instance;
   }
 
@@ -103,7 +107,7 @@ public function getPluginInstance($plugin_id) {
    * @return string
    *   Configuration object name.
    */
-  protected function getConfigId() {
+  protected function getConfigId(): string {
     return $this->getConfigName() . '.' . $this->getPluginIdFromRequest();
   }
 
diff --git a/src/Form/PluginSettingsFormInterface.php b/src/Form/PluginSettingsFormInterface.php
index 5636c40..3cc4f3c 100644
--- a/src/Form/PluginSettingsFormInterface.php
+++ b/src/Form/PluginSettingsFormInterface.php
@@ -15,6 +15,6 @@ interface PluginSettingsFormInterface {
    * @return string
    *   Configuration name for plugins.
    */
-  public static function getConfigName();
+  public static function getConfigName(): string;
 
 }
diff --git a/src/LookupResult/CompanyLookupResult.php b/src/LookupResult/CompanyLookupResult.php
index 96bc0b7..ae1446b 100644
--- a/src/LookupResult/CompanyLookupResult.php
+++ b/src/LookupResult/CompanyLookupResult.php
@@ -2,6 +2,9 @@
 
 namespace Drupal\os2web_datalookup\LookupResult;
 
+/**
+ * Representation or value object for the result of a company lookup.
+ */
 class CompanyLookupResult {
 
   const CVR = 'cvr';
@@ -20,248 +23,320 @@ class CompanyLookupResult {
    *
    * @var bool
    */
-  protected $successful = FALSE;
+  protected bool $successful = FALSE;
 
   /**
    * Status of the request.
    *
    * @var string
    */
-  protected $errorMessage;
+  protected string $errorMessage;
 
   /**
-   * CVR
+   * The CVR number.
    *
    * @var string
    */
-  protected $cvr;
+  protected string $cvr;
 
   /**
    * Company name.
    *
    * @var string
    */
-  protected $name;
+  protected string $name;
 
   /**
    * Street of the person.
    *
    * @var string
    */
-  protected $street;
+  protected string $street;
 
   /**
    * Street house number of the person.
    *
    * @var string
    */
-  protected $houseNr;
+  protected string $houseNr;
 
   /**
-   * Floor number the person.
+   * Floor number of the person.
    *
    * @var string
    */
-  protected $floor;
+  protected string $floor;
 
   /**
    * Apartment number of the person.
    *
    * @var string
    */
-  protected $apartmentNr;
+  protected string $apartmentNr;
 
   /**
    * Postal code of the person.
    *
    * @var string
    */
-  protected $postalCode;
+  protected string $postalCode;
 
   /**
    * City of the person.
    *
    * @var string
    */
-  protected $city;
+  protected string $city;
 
   /**
    * Municipality code of the person.
    *
    * @var string
    */
-  protected $municipalityCode;
+  protected string $municipalityCode;
 
   /**
    * Address of the person.
    *
    * @var string
    */
-  protected $address;
+  protected string $address;
 
   /**
+   * Check the state of successful.
+   *
    * @return bool
+   *   TRUE if successfully else FALSE.
    */
   public function isSuccessful(): bool {
     return $this->successful;
   }
 
   /**
+   * The state of successful.
+   *
    * @param bool $successful
+   *   The state.
    */
   public function setSuccessful(bool $successful = TRUE): void {
     $this->successful = $successful;
   }
 
   /**
+   * Get error message.
+   *
    * @return string
+   *   The error message.
    */
   public function getErrorMessage(): string {
     return $this->errorMessage;
   }
 
   /**
+   * Set error message.
+   *
    * @param string $errorMessage
+   *   The error message.
    */
   public function setErrorMessage(string $errorMessage): void {
     $this->errorMessage = $errorMessage;
   }
 
   /**
+   * Get CVR number.
+   *
    * @return string
+   *   The number.
    */
   public function getCvr(): string {
     return $this->cvr;
   }
 
   /**
+   * Set CVR number.
+   *
    * @param string $cpr
+   *   The number.
    */
   public function setCvr(string $cpr): void {
     $this->cvr = $cpr;
   }
 
   /**
+   * Get name.
+   *
    * @return string
+   *   The name.
    */
   public function getName(): string {
     return $this->name;
   }
 
   /**
+   * Set name.
+   *
    * @param string $name
+   *   The name.
    */
   public function setName(string $name): void {
     $this->name = $name;
   }
 
   /**
+   * Get street.
+   *
    * @return string
+   *   The street.
    */
   public function getStreet(): string {
     return $this->street;
   }
 
   /**
+   * Set street.
+   *
    * @param string $street
+   *   The street.
    */
   public function setStreet(string $street): void {
     $this->street = $street;
   }
 
   /**
+   * Get house number.
+   *
    * @return string
+   *   The number.
    */
   public function getHouseNr(): string {
     return $this->houseNr;
   }
 
   /**
+   * Set hous number.
+   *
    * @param string $houseNr
+   *   The number.
    */
   public function setHouseNr(string $houseNr): void {
     $this->houseNr = $houseNr;
   }
 
   /**
+   * Get a floor.
+   *
    * @return string
+   *   The floor.
    */
   public function getFloor(): string {
     return $this->floor;
   }
 
   /**
+   * Set floor.
+   *
    * @param string $floor
+   *   The floor.
    */
   public function setFloor(string $floor): void {
     $this->floor = $floor;
   }
 
   /**
+   * Get apartment number.
+   *
    * @return string
+   *   The number.
    */
   public function getApartmentNr(): string {
     return $this->apartmentNr;
   }
 
   /**
+   * Set apartment number.
+   *
    * @param string $apartmentNr
+   *   The number.
    */
   public function setApartmentNr(string $apartmentNr): void {
     $this->apartmentNr = $apartmentNr;
   }
 
   /**
+   * Get postal code.
+   *
    * @return string
+   *   The code.
    */
   public function getPostalCode(): string {
     return $this->postalCode;
   }
 
   /**
+   * Set postal code.
+   *
    * @param string $postalCode
+   *   The code.
    */
   public function setPostalCode(string $postalCode): void {
     $this->postalCode = $postalCode;
   }
 
   /**
+   * Get city.
+   *
    * @return string
+   *   The city.
    */
   public function getCity(): string {
     return $this->city;
   }
 
   /**
+   * Set city.
+   *
    * @param string $city
+   *   The city.
    */
   public function setCity(string $city): void {
     $this->city = $city;
   }
 
   /**
+   * Get municipality code.
+   *
    * @return string
+   *   The code.
    */
   public function getMunicipalityCode(): string {
     return $this->municipalityCode;
   }
 
   /**
+   * Set municipality code.
+   *
    * @param string $municipalityCode
+   *   The code.
    */
   public function setMunicipalityCode(string $municipalityCode): void {
     $this->municipalityCode = $municipalityCode;
   }
 
   /**
+   * Get address.
+   *
    * @return string
+   *   The address.
    */
   public function getAddress(): string {
     return $this->address;
   }
 
   /**
+   * Set address.
+   *
    * @param string $address
+   *   The address to set.
    */
   public function setAddress(string $address): void {
     $this->address = $address;
@@ -270,12 +345,13 @@ public function setAddress(string $address): void {
   /**
    * Returns the value of the provided field.
    *
-   * @param $field
+   * @param string $field
    *   Field name.
    *
    * @return mixed
+   *   The field value or the empty string if the field does not exist.
    */
-  public function getFieldValue($field) {
+  public function getFieldValue(string $field): mixed {
     if (property_exists($this, $field)) {
       return $this->{$field};
     }
diff --git a/src/LookupResult/CprLookupResult.php b/src/LookupResult/CprLookupResult.php
index d553f68..91703cc 100644
--- a/src/LookupResult/CprLookupResult.php
+++ b/src/LookupResult/CprLookupResult.php
@@ -2,6 +2,9 @@
 
 namespace Drupal\os2web_datalookup\LookupResult;
 
+/**
+ * Representation or value object for the result of a CPR lookup.
+ */
 class CprLookupResult {
 
   const CPR = 'cpr';
@@ -21,133 +24,133 @@ class CprLookupResult {
    *
    * @var bool
    */
-  protected $successful = FALSE;
+  protected bool $successful = FALSE;
 
   /**
    * Status of the request.
    *
    * @var string
    */
-  protected $errorMessage;
+  protected string $errorMessage;
 
   /**
-   * CPR
+   * CPR number.
    *
    * @var string
    */
-  protected $cpr;
+  protected string $cpr;
 
   /**
    * Name of the person.
    *
    * @var string
    */
-  protected $name;
+  protected string $name;
 
   /**
    * Street of the person.
    *
    * @var string
    */
-  protected $street;
+  protected string $street;
 
   /**
    * Street house number of the person.
    *
    * @var string
    */
-  protected $houseNr;
+  protected string $houseNr;
 
   /**
    * Floor number the person.
    *
    * @var string
    */
-  protected $floor;
+  protected string $floor;
 
   /**
    * Apartment number of the person.
    *
    * @var string
    */
-  protected $apartmentNr;
+  protected string $apartmentNr;
 
   /**
    * Postal code of the person.
    *
    * @var string
    */
-  protected $postalCode;
+  protected string $postalCode;
 
   /**
    * City of the person.
    *
    * @var string
    */
-  protected $city;
+  protected string $city;
 
   /**
    * Municipality code of the person.
    *
    * @var string
    */
-  protected $municipalityCode;
+  protected string $municipalityCode;
 
   /**
    * Address of the person.
    *
    * @var string
    */
-  protected $address;
+  protected string $address;
 
   /**
    * CO Name of the person.
    *
    * @var string
    */
-  protected $coName;
+  protected string $coName;
 
   /**
    * Is name/address protected of the person.
    *
    * @var bool
    */
-  protected $nameAddressProtected = FALSE;
+  protected bool $nameAddressProtected = FALSE;
 
   /**
    * Array of children.
    *
    * @var array
    */
-  protected $children = [];
+  protected array $children = [];
 
   /**
    * Array of guardians.
    *
    * @var array
    */
-  protected $guardians = [];
+  protected array $guardians = [];
 
   /**
-   * Is subscribe to digital post.
+   * Is subscribed to digital post.
    *
    * @var bool
    */
-  protected $digitalPostSubscribed = FALSE;
+  protected bool $digitalPostSubscribed = FALSE;
 
   /**
    * Is alive.
    *
    * @var bool
    */
-  protected $alive = TRUE;
+  protected bool $alive = TRUE;
 
   /**
    * Is Danish citizen.
    *
    * @var bool
    */
-  protected $citizen = TRUE;
+  protected bool $citizen = TRUE;
 
   /**
    * Citizenship date obtained.
@@ -164,196 +167,280 @@ class CprLookupResult {
   protected \DateTime $birthDate;
 
   /**
+   * Check successfulness state.
+   *
    * @return bool
+   *   TRUE on success else FALSE.
    */
   public function isSuccessful(): bool {
     return $this->successful;
   }
 
   /**
+   * Set state of successfulness.
+   *
    * @param bool $successful
+   *   The state.
    */
   public function setSuccessful(bool $successful = TRUE): void {
     $this->successful = $successful;
   }
 
   /**
+   * Get an error message.
+   *
    * @return string
+   *   The message.
    */
   public function getErrorMessage(): string {
     return $this->errorMessage;
   }
 
   /**
+   * Set error message.
+   *
    * @param string $errorMessage
+   *   The message.
    */
   public function setErrorMessage(string $errorMessage): void {
     $this->errorMessage = $errorMessage;
   }
 
   /**
+   * Get CPR number.
+   *
    * @return string
+   *   The number.
    */
   public function getCpr(): string {
     return $this->cpr;
   }
 
   /**
+   * Set CPR number.
+   *
    * @param string $cpr
+   *   The number.
    */
   public function setCpr(string $cpr): void {
     $this->cpr = $cpr;
   }
 
   /**
+   * Get name.
+   *
    * @return string
+   *   The name.
    */
   public function getName(): string {
     return $this->name;
   }
 
   /**
+   * Set name.
+   *
    * @param string $name
+   *   The name.
    */
   public function setName(string $name): void {
     $this->name = $name;
   }
 
   /**
+   * Get street.
+   *
    * @return string
+   *   The street.
    */
   public function getStreet(): string {
     return $this->street;
   }
 
   /**
+   * Set street.
+   *
    * @param string $street
+   *   The street.
    */
   public function setStreet(string $street): void {
     $this->street = $street;
   }
 
   /**
+   * Get house number.
+   *
    * @return string
+   *   The number.
    */
   public function getHouseNr(): string {
     return $this->houseNr;
   }
 
   /**
+   * Set house number.
+   *
    * @param string $houseNr
+   *   The number.
    */
   public function setHouseNr(string $houseNr): void {
     $this->houseNr = $houseNr;
   }
 
   /**
+   * Get floor.
+   *
    * @return string
+   *   The floor.
    */
   public function getFloor(): string {
     return $this->floor;
   }
 
   /**
+   * Set floor.
+   *
    * @param string $floor
+   *   The floor.
    */
   public function setFloor(string $floor): void {
     $this->floor = $floor;
   }
 
   /**
+   * Get apartment number.
+   *
    * @return string
+   *   The number.
    */
   public function getApartmentNr(): string {
     return $this->apartmentNr;
   }
 
   /**
+   * Set apartment number.
+   *
    * @param string $apartmentNr
+   *   The number.
    */
   public function setApartmentNr(string $apartmentNr): void {
     $this->apartmentNr = $apartmentNr;
   }
 
   /**
+   * Get postal code.
+   *
    * @return string
+   *   The code.
    */
   public function getPostalCode(): string {
     return $this->postalCode;
   }
 
   /**
+   * Set postal code.
+   *
    * @param string $postalCode
+   *   The code.
    */
   public function setPostalCode(string $postalCode): void {
     $this->postalCode = $postalCode;
   }
 
   /**
+   * Get city name.
+   *
    * @return string
+   *   The name.
    */
   public function getCity(): string {
     return $this->city;
   }
 
   /**
+   * Set city.
+   *
    * @param string $city
+   *   The city name.
    */
   public function setCity(string $city): void {
     $this->city = $city;
   }
 
   /**
+   * Get municipality code.
+   *
    * @return string
+   *   The code.
    */
   public function getMunicipalityCode(): string {
     return $this->municipalityCode;
   }
 
   /**
+   * Set municipality code.
+   *
    * @param string $municipalityCode
+   *   The code.
    */
   public function setMunicipalityCode(string $municipalityCode): void {
     $this->municipalityCode = $municipalityCode;
   }
 
   /**
+   * Get address.
+   *
    * @return string
+   *   The address.
    */
   public function getAddress(): string {
     return $this->address;
   }
 
   /**
+   * Set address.
+   *
    * @param string $address
+   *   The address.
    */
   public function setAddress(string $address): void {
     $this->address = $address;
   }
 
   /**
+   * Get CO name.
+   *
    * @return string
+   *   The CO name.
    */
   public function getCoName(): string {
     return $this->coName;
   }
 
   /**
+   * Set CO name.
+   *
    * @param string $coName
+   *   The CO name to set.
    */
   public function setCoName(string $coName): void {
     $this->coName = $coName;
   }
 
   /**
+   * Check if the address is protected.
+   *
    * @return bool
+   *   TRUE if it is else FALSE.
    */
   public function isNameAddressProtected(): bool {
     return $this->nameAddressProtected;
   }
 
   /**
+   * Set address protected state.
+   *
    * @param bool $nameAddressProtected
+   *   TRUE if protected else FALSE.
    */
   public function setNameAddressProtected(bool $nameAddressProtected): void {
     $this->nameAddressProtected = $nameAddressProtected;
@@ -370,7 +457,7 @@ public function setNameAddressProtected(bool $nameAddressProtected): void {
    *       'name' => full name,
    *     ],
    *     ...
-   *   ]
+   *   ].
    */
   public function getChildren(): array {
     return $this->children;
@@ -388,7 +475,7 @@ public function getChildren(): array {
    *       'nameAddressProtected' => TRUE/FALSE
    *     ],
    *     ...
-   *   ]
+   *   ].
    */
   public function setChildren(array $children): void {
     $this->children = $children;
@@ -406,7 +493,7 @@ public function setChildren(array $children): void {
    *       'nameAddressProtected' => TRUE/FALSE
    *     ],
    *     ...
-   *   ]
+   *   ].
    */
   public function getGuardians(): array {
     return $this->guardians;
@@ -423,77 +510,107 @@ public function getGuardians(): array {
    *       'type' => 1|2|3|4,
    *     ],
    *     ...
-   *   ]
+   *   ].
    */
   public function setGuardians(array $guardians): void {
     $this->guardians = $guardians;
   }
 
   /**
+   * Set digital post subscriber state.
+   *
    * @param bool $digitalPostSubscribed
+   *   The state.
    */
   public function setDigitalPostSubscribed(bool $digitalPostSubscribed): void {
     $this->digitalPostSubscribed = $digitalPostSubscribed;
   }
 
   /**
+   * Check the state of digital post subscription.
+   *
    * @return bool
+   *   TRUE if subscriber else FALSE.
    */
   public function isDigitalPostSubscribed(): bool {
     return $this->digitalPostSubscribed;
   }
 
   /**
+   * Check is citizen is alive.
+   *
    * @return bool
+   *   The living state.
    */
   public function isAlive(): bool {
     return $this->alive;
   }
 
   /**
+   * Set is alive.
+   *
    * @param bool $alive
+   *   TRUE if alive else FALSE.
    */
   public function setAlive(bool $alive): void {
     $this->alive = $alive;
   }
 
   /**
+   * Check if this is a citizen.
+   *
    * @return bool
+   *   TRUE if it is else FALSE.
    */
   public function isCitizen(): bool {
     return $this->citizen;
   }
 
   /**
+   * Set citizen.
+   *
    * @param bool $citizen
+   *   The citizen (TRUE or FALSE).
    */
   public function setCitizen(bool $citizen): void {
     $this->citizen = $citizen;
   }
 
   /**
+   * Get citizenship date.
+   *
    * @return \DateTime
+   *   The date.
    */
   public function getCitizenshipDate(): \DateTime {
     return $this->citizenshipDate;
   }
 
   /**
+   * Set citizenship date.
+   *
    * @param \DateTime $citizenshipDate
+   *   The date.
    */
   public function setCitizenshipDate(\DateTime $citizenshipDate): void {
     $this->citizenshipDate = $citizenshipDate;
   }
 
   /**
+   * Get birthdate.
+   *
    * @return \DateTime
+   *   The date.
    */
   public function getBirthDate(): \DateTime {
     return $this->birthDate;
   }
 
   /**
+   * Set birthdate.
+   *
    * @param \DateTime $birthDate
+   *   The date.
    */
   public function setBirthDate(\DateTime $birthDate): void {
     $this->birthDate = $birthDate;
@@ -502,13 +619,13 @@ public function setBirthDate(\DateTime $birthDate): void {
   /**
    * Checks if the provided CPR is in list of guardians.
    *
-   * @param $cpr
+   * @param string $cpr
    *   Cpr number.
    *
    * @return bool
-   *   TRUE if person has provided CPR as guardian, FALSE otherwise.
+   *   TRUE if a person has provided CPR as guardian, FALSE otherwise.
    */
-  public function hasGuardian($cpr): bool {
+  public function hasGuardian(string $cpr): bool {
     foreach ($this->guardians as $guardian) {
       if ($guardian['cpr'] == $cpr) {
         return TRUE;
@@ -521,12 +638,13 @@ public function hasGuardian($cpr): bool {
   /**
    * Returns the value of the provided field.
    *
-   * @param $field
+   * @param string $field
    *   Field name.
    *
    * @return mixed
+   *   The value of the field or the empty string.
    */
-  public function getFieldValue($field) {
+  public function getFieldValue(string $field): mixed {
     if (property_exists($this, $field)) {
       return $this->{$field};
     }
diff --git a/src/Plugin/DataLookupManager.php b/src/Plugin/DataLookupManager.php
index b0744c0..128b067 100644
--- a/src/Plugin/DataLookupManager.php
+++ b/src/Plugin/DataLookupManager.php
@@ -2,10 +2,10 @@
 
 namespace Drupal\os2web_datalookup\Plugin;
 
-use Drupal\Core\Config\ConfigFactoryInterface;
-use Drupal\Core\Plugin\DefaultPluginManager;
 use Drupal\Core\Cache\CacheBackendInterface;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Plugin\DefaultPluginManager;
 use Drupal\os2web_datalookup\Form\DataLookupPluginGroupSettingsForm;
 use Drupal\os2web_datalookup\Form\DataLookupPluginSettingsForm;
 
@@ -89,14 +89,14 @@ public function createDefaultInstanceByGroup(string $group_id): object {
   /**
    * Gets the definition of all plugins for this type based on group.
    *
-   * @param $group_id
+   * @param string $group_id
    *   Group id.
    *
    * @return array
    *   An array of plugin definitions (empty array if no definitions were
    *   found). Keys are plugin IDs.
    */
-  public function getDefinitionsByGroup($group_id): array {
+  public function getDefinitionsByGroup(string $group_id): array {
     $definitions = [];
     foreach ($this->getDefinitions() as $id => $plugin_definition) {
       if ($plugin_definition['group'] == $group_id) {
@@ -126,15 +126,15 @@ public function getDatalookupGroups(): array {
   }
 
   /**
-   * Returns the group default plugin
+   * Returns the group default plugin.
    *
-   * @param $group_id
+   * @param string $group_id
    *   Group ID.
    *
    * @return string|null
    *   Plugin ID or NULL is not set.
    */
-  public function getGroupDefaultPlugin($group_id): ?string {
+  public function getGroupDefaultPlugin(string $group_id): ?string {
     $config = \Drupal::config(DataLookupPluginGroupSettingsForm::$configName);
 
     return $config->get("$group_id.default_plugin");
diff --git a/src/Plugin/Derivative/GroupSettingsLocalTasks.php b/src/Plugin/Derivative/GroupSettingsLocalTasks.php
index 78e5ee6..631e3bf 100644
--- a/src/Plugin/Derivative/GroupSettingsLocalTasks.php
+++ b/src/Plugin/Derivative/GroupSettingsLocalTasks.php
@@ -5,6 +5,7 @@
 use Drupal\Component\Plugin\Derivative\DeriverBase;
 use Drupal\Component\Plugin\PluginManagerInterface;
 use Drupal\Core\Plugin\Discovery\ContainerDeriverInterface;
+use Drupal\os2web_datalookup\Plugin\DataLookupManager;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
@@ -12,14 +13,18 @@
  */
 class GroupSettingsLocalTasks extends DeriverBase implements ContainerDeriverInterface {
 
-  /** @var \Drupal\os2web_datalookup\Plugin\DataLookupManager */
-  protected $dataLookupManager;
+  /**
+   * Data lookup manager.
+   *
+   * @var \Drupal\os2web_datalookup\Plugin\DataLookupManager
+   */
+  protected DataLookupManager $dataLookupManager;
 
   /**
    * Constructs a new GroupSettingsLocalTasks object.
    *
-   * @param \Drupal\os2web_datalookup\Plugin\DataLookupManager
-   *   Datalookup manager.
+   * @param \Drupal\Component\Plugin\PluginManagerInterface $dataLookupManager
+   *   Data lookup manager.
    */
   public function __construct(PluginManagerInterface $dataLookupManager) {
     $this->dataLookupManager = $dataLookupManager;
@@ -28,7 +33,7 @@ public function __construct(PluginManagerInterface $dataLookupManager) {
   /**
    * {@inheritdoc}
    */
-  public static function create(ContainerInterface $container, $base_plugin_id) {
+  public static function create(ContainerInterface $container, $base_plugin_id): static {
     return new static(
       $container->get('plugin.manager.os2web_datalookup')
     );
@@ -37,8 +42,9 @@ public static function create(ContainerInterface $container, $base_plugin_id) {
   /**
    * {@inheritdoc}
    */
-  public function getDerivativeDefinitions($base_plugin_definition) {
-    // Implement dynamic logic to provide values for the same keys as in example.links.task.yml.
+  public function getDerivativeDefinitions($base_plugin_definition): array {
+    // Implement dynamic logic to provide values for the same keys as in
+    // example.links.task.yml.
     $groups = $this->dataLookupManager->getDatalookupGroups();
 
     foreach ($groups as $group) {
diff --git a/src/Plugin/os2web/DataLookup/DataLookupInterfaceCompany.php b/src/Plugin/os2web/DataLookup/DataLookupCompanyInterface.php
similarity index 62%
rename from src/Plugin/os2web/DataLookup/DataLookupInterfaceCompany.php
rename to src/Plugin/os2web/DataLookup/DataLookupCompanyInterface.php
index 82b9fb2..fa0fd19 100644
--- a/src/Plugin/os2web/DataLookup/DataLookupInterfaceCompany.php
+++ b/src/Plugin/os2web/DataLookup/DataLookupCompanyInterface.php
@@ -4,7 +4,15 @@
 
 use Drupal\os2web_datalookup\LookupResult\CompanyLookupResult;
 
-interface DataLookupInterfaceCompany extends DataLookupInterface {
+/**
+ * DataLookupInterfaceCompany plugin interface.
+ *
+ * This interface provides some simple tools for code receiving a plugin to
+ * interact with the plugin system.
+ *
+ * @ingroup plugin_api
+ */
+interface DataLookupCompanyInterface extends DataLookupInterface {
 
   /**
    * Performs lookup for the provided param.
diff --git a/src/Plugin/os2web/DataLookup/DataLookupInterfaceCpr.php b/src/Plugin/os2web/DataLookup/DataLookupCprInterface.php
similarity index 80%
rename from src/Plugin/os2web/DataLookup/DataLookupInterfaceCpr.php
rename to src/Plugin/os2web/DataLookup/DataLookupCprInterface.php
index 8e36140..3662f0a 100644
--- a/src/Plugin/os2web/DataLookup/DataLookupInterfaceCpr.php
+++ b/src/Plugin/os2web/DataLookup/DataLookupCprInterface.php
@@ -4,7 +4,10 @@
 
 use Drupal\os2web_datalookup\LookupResult\CprLookupResult;
 
-interface DataLookupInterfaceCpr extends DataLookupInterface {
+/**
+ * Data lookup CPR interface.
+ */
+interface DataLookupCprInterface extends DataLookupInterface {
 
   /**
    * Performs lookup for the provided CPR.
diff --git a/src/Plugin/os2web/DataLookup/DataLookupInterface.php b/src/Plugin/os2web/DataLookup/DataLookupInterface.php
index e703814..2ce2e39 100644
--- a/src/Plugin/os2web/DataLookup/DataLookupInterface.php
+++ b/src/Plugin/os2web/DataLookup/DataLookupInterface.php
@@ -5,7 +5,6 @@
 use Drupal\Component\Plugin\ConfigurableInterface;
 use Drupal\Component\Plugin\PluginInspectionInterface;
 use Drupal\Core\Plugin\PluginFormInterface;
-use Drupal\Core\StringTranslation\TranslatableMarkup;
 
 /**
  * DataLookupInterface plugin interface for providing some metadata inspection.
diff --git a/src/Plugin/os2web/DataLookup/DatafordelerBase.php b/src/Plugin/os2web/DataLookup/DatafordelerBase.php
index f5ee198..9c3179a 100644
--- a/src/Plugin/os2web/DataLookup/DatafordelerBase.php
+++ b/src/Plugin/os2web/DataLookup/DatafordelerBase.php
@@ -14,7 +14,7 @@ abstract class DatafordelerBase extends DataLookupBase {
   /**
    * Http client.
    *
-   * @var Client
+   * @var \GuzzleHttp\Client
    */
   protected Client $httpClient;
 
diff --git a/src/Plugin/os2web/DataLookup/DatafordelerCVR.php b/src/Plugin/os2web/DataLookup/DatafordelerCVR.php
index b35db08..3b597d3 100644
--- a/src/Plugin/os2web/DataLookup/DatafordelerCVR.php
+++ b/src/Plugin/os2web/DataLookup/DatafordelerCVR.php
@@ -17,7 +17,7 @@
  *   group = "cvr_lookup"
  * )
  */
-class DatafordelerCVR extends DatafordelerBase implements DataLookupInterfaceCompany {
+class DatafordelerCVR extends DatafordelerBase implements DataLookupCompanyInterface {
 
   /**
    * {@inheritdoc}
diff --git a/src/Plugin/os2web/DataLookup/DatafordelerPNumber.php b/src/Plugin/os2web/DataLookup/DatafordelerPNumber.php
index cf67257..efecd5d 100644
--- a/src/Plugin/os2web/DataLookup/DatafordelerPNumber.php
+++ b/src/Plugin/os2web/DataLookup/DatafordelerPNumber.php
@@ -7,7 +7,6 @@
 use Drupal\Core\Render\Markup;
 use Drupal\os2web_datalookup\LookupResult\CompanyLookupResult;
 use GuzzleHttp\Exception\ClientException;
-use function Symfony\Component\String\s;
 
 /**
  * Defines a plugin for DatafordelerPNumber.
@@ -18,7 +17,7 @@
  *   group = "pnumber_lookup"
  * )
  */
-class DatafordelerPNumber extends DatafordelerBase implements DataLookupInterfaceCompany {
+class DatafordelerPNumber extends DatafordelerBase implements DataLookupCompanyInterface {
 
   /**
    * {@inheritdoc}
diff --git a/src/Plugin/os2web/DataLookup/ServiceplatformenCPR.php b/src/Plugin/os2web/DataLookup/ServiceplatformenCPRInterface.php
similarity index 81%
rename from src/Plugin/os2web/DataLookup/ServiceplatformenCPR.php
rename to src/Plugin/os2web/DataLookup/ServiceplatformenCPRInterface.php
index b0d9e61..4112741 100644
--- a/src/Plugin/os2web/DataLookup/ServiceplatformenCPR.php
+++ b/src/Plugin/os2web/DataLookup/ServiceplatformenCPRInterface.php
@@ -8,7 +8,7 @@
 use Drupal\os2web_datalookup\LookupResult\CprLookupResult;
 
 /**
- * Defines a plugin for ServiceplatformenCPR.
+ * Defines a plugin for ServiceplatformenCPRInterface.
  *
  * @DataLookup(
  *   id = "serviceplatformen_cpr",
@@ -16,7 +16,7 @@
  *   group = "cpr_lookup"
  * )
  */
-class ServiceplatformenCPR extends ServiceplatformenBase implements DataLookupInterfaceCpr {
+class ServiceplatformenCPRInterface extends ServiceplatformenBase implements DataLookupCprInterface {
 
   /**
    * {@inheritdoc}
@@ -38,7 +38,7 @@ public function buildConfigurationForm(array $form, FormStateInterface $form_sta
       '#default_value' => $this->configuration['test_mode_fixed_cpr'],
       '#description' => $this->t('Fixed CPR that will be used for all requests to the serviceplatformen instead of the provided CPR.'),
       '#states' => [
-        // Hide the settings when the "cancel notify" checkbox is disabled.
+        // Hide the settings when the "cancel notifies" checkbox is disabled.
         'visible' => [
           'input[name="mode_selector"]' => ['value' => 1],
         ],
@@ -105,7 +105,8 @@ public function cprBasicInformation(string $cpr): array {
   /**
    * Validate cpr callback.
    *
-   * @param string $cpr  - PSN (cpr) ([0-9]{6}\-[0-9]{4})
+   * @param string $cpr
+   *   PSN (cpr) ([0-9]{6}\-[0-9]{4})
    *
    * @return array
    *   [status] => TRUE/FALSE
@@ -119,18 +120,18 @@ public function validateCpr(string $cpr): array {
    * Fetch address for the specified CPR.
    *
    * @param string $cpr
-   *  String - PSN (cpr) ([0-9]{6}\-[0-9]{4})
+   *   String - PSN (cpr) ([0-9]{6}\-[0-9]{4})
    *
-   * @return array
+   * @return array<string, mixed>
    *   [status] => TRUE/FALSE
    *   [address] => Roadname 10
    *   [zipcode] => 1212
    *   [error] => Descriptive text if something goes wrong
-   *@deprecated use lookup() instead.
    *
+   * @deprecated use lookup() instead.
    */
   public function getAddress(string $cpr): array {
-    \Drupal::logger('os2web_datalookup')->notice('Calling \'getAddress()\' directly is deprecated, use DataLookupInterfaceCpr::lookup() method.');
+    \Drupal::logger('os2web_datalookup')->notice('Calling \'getAddress()\' directly is deprecated, use DataLookupCprInterface::lookup() method.');
 
     $result = $this->cprBasicInformation($cpr);
 
@@ -139,25 +140,24 @@ public function getAddress(string $cpr): array {
       return [
         'status' => $result['status'],
         'cpr' => $cpr,
-        'name' => isset($result['adresseringsnavn']) ? $result['adresseringsnavn'] : '',
-        'road' => isset($result['vejadresseringsnavn']) ? $result['vejadresseringsnavn'] : '',
+        'name' => $result['adresseringsnavn'] ?? '',
+        'road' => $result['vejadresseringsnavn'] ?? '',
         'road_no' => isset($result['husnummer']) ? ltrim($result['husnummer'], '0') : '',
-        'floor' => isset($result['etage']) ? $result['etage'] : '',
-        'door' => isset($result['sidedoer']) ? ltrim($result['sidedoer'], '0')  : '',
-        'zipcode' => isset($result['postnummer']) ? $result['postnummer'] : '',
-        'city' => isset($result['postdistrikt']) ? $result['postdistrikt'] : '',
-        'coname' => isset($result['conavn']) ? $result['conavn'] : '',
-        'kommunekode' => isset($result['kommunekode']) ? $result['kommunekode'] : '',
-        'name_address_protected' => isset($result['navneOgAdressebeskyttelse']) ? $result['navneOgAdressebeskyttelse'] : '',
+        'floor' => $result['etage'] ?? '',
+        'door' => isset($result['sidedoer']) ? ltrim($result['sidedoer'], '0') : '',
+        'zipcode' => $result['postnummer'] ?? '',
+        'city' => $result['postdistrikt'] ?? '',
+        'coname' => $result['conavn'] ?? '',
+        'kommunekode' => $result['kommunekode'] ?? '',
+        'name_address_protected' => $result['navneOgAdressebeskyttelse'] ?? '',
       ];
     }
-    else {
-      return $result;
-    }
+
+    return $result;
   }
 
   /**
-   * @inheritDoc
+   * {@inheritDoc}
    */
   public function lookup(string $cpr): CprLookupResult {
     $result = $this->cprBasicInformation($cpr);
@@ -187,4 +187,5 @@ public function lookup(string $cpr): CprLookupResult {
 
     return $cprResult;
   }
+
 }
diff --git a/src/Plugin/os2web/DataLookup/ServiceplatformenCPRExtended.php b/src/Plugin/os2web/DataLookup/ServiceplatformenCPRInterfaceExtended.php
similarity index 94%
rename from src/Plugin/os2web/DataLookup/ServiceplatformenCPRExtended.php
rename to src/Plugin/os2web/DataLookup/ServiceplatformenCPRInterfaceExtended.php
index bc38d48..639ee59 100644
--- a/src/Plugin/os2web/DataLookup/ServiceplatformenCPRExtended.php
+++ b/src/Plugin/os2web/DataLookup/ServiceplatformenCPRInterfaceExtended.php
@@ -2,15 +2,13 @@
 
 namespace Drupal\os2web_datalookup\Plugin\os2web\DataLookup;
 
-use DateTime;
-use DateTimeInterface;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Messenger\MessengerInterface;
 use Drupal\Core\Render\Markup;
 use Drupal\os2web_datalookup\LookupResult\CprLookupResult;
 
 /**
- * Defines a plugin for ServiceplatformenCPRExtended.
+ * Defines a plugin for ServiceplatformenCPRInterfaceExtended.
  *
  * @DataLookup(
  *   id = "serviceplatformen_cpr_extended",
@@ -18,7 +16,7 @@
  *   group = "cpr_lookup"
  * )
  */
-class ServiceplatformenCPRExtended extends ServiceplatformenBase implements DataLookupInterfaceCpr {
+class ServiceplatformenCPRInterfaceExtended extends ServiceplatformenBase implements DataLookupCprInterface {
 
   /**
    * Status = DEAD.
@@ -70,7 +68,7 @@ public function buildConfigurationForm(array $form, FormStateInterface $form_sta
       '#default_value' => $this->configuration['test_mode_fixed_cpr'],
       '#description' => $this->t('Fixed CPR that will be used for all requests to the serviceplatformen instead of the provided CPR.'),
       '#states' => [
-        // Hide the settings when the cancel notify checkbox is disabled.
+        // Hide the settings when the cancel notifies checkbox is disabled.
         'visible' => [
           'input[name="mode_selector"]' => ['value' => 1],
         ],
@@ -148,7 +146,7 @@ public function lookup(string $cpr, $fetchChildren = TRUE, $allowCprTestModeRepl
           $cprResult->setCitizen(FALSE);
         }
 
-        $citizenshipDate = DateTime::createFromFormat(DateTimeInterface::RFC3339_EXTENDED, $persondata->statsborgerskab->statsborgerskabDato->dato);
+        $citizenshipDate = \DateTime::createFromFormat(\DateTimeInterface::RFC3339_EXTENDED, $persondata->statsborgerskab->statsborgerskabDato->dato);
         $cprResult->setCitizenshipDate($citizenshipDate);
       }
 
@@ -157,7 +155,7 @@ public function lookup(string $cpr, $fetchChildren = TRUE, $allowCprTestModeRepl
       }
 
       if ($persondata->foedselsdato) {
-        $birthDate = DateTime::createFromFormat("Y-m-dP", $persondata->foedselsdato->dato);
+        $birthDate = \DateTime::createFromFormat("Y-m-dP", $persondata->foedselsdato->dato);
         $cprResult->setBirthDate($birthDate);
       }
 
diff --git a/src/Plugin/os2web/DataLookup/ServiceplatformenCVR.php b/src/Plugin/os2web/DataLookup/ServiceplatformenCVR.php
index ec30650..b59e762 100644
--- a/src/Plugin/os2web/DataLookup/ServiceplatformenCVR.php
+++ b/src/Plugin/os2web/DataLookup/ServiceplatformenCVR.php
@@ -16,7 +16,7 @@
  *   group = "cvr_lookup"
  * )
  */
-class ServiceplatformenCVR extends ServiceplatformenBase implements DataLookupInterfaceCompany {
+class ServiceplatformenCVR extends ServiceplatformenBase implements DataLookupCompanyInterface {
 
   /**
    * {@inheritdoc}
diff --git a/src/Plugin/os2web/DataLookup/ServiceplatformenPNumber.php b/src/Plugin/os2web/DataLookup/ServiceplatformenPNumber.php
index 1363dfc..3487d33 100644
--- a/src/Plugin/os2web/DataLookup/ServiceplatformenPNumber.php
+++ b/src/Plugin/os2web/DataLookup/ServiceplatformenPNumber.php
@@ -16,7 +16,7 @@
  *   group = "pnumber_lookup"
  * )
  */
-class ServiceplatformenPNumber extends ServiceplatformenBase implements DataLookupInterfaceCompany {
+class ServiceplatformenPNumber extends ServiceplatformenBase implements DataLookupCompanyInterface {
 
   /**
    * {@inheritdoc}
diff --git a/src/Routing/DataLookupRoutes.php b/src/Routing/DataLookupRoutes.php
index 046943e..4e168e2 100644
--- a/src/Routing/DataLookupRoutes.php
+++ b/src/Routing/DataLookupRoutes.php
@@ -2,8 +2,9 @@
 
 namespace Drupal\os2web_datalookup\Routing;
 
-use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
 use Drupal\Component\Plugin\PluginManagerInterface;
+use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\Routing\Route;
 
@@ -12,12 +13,14 @@
  */
 class DataLookupRoutes implements ContainerInjectionInterface {
 
+  use StringTranslationTrait;
+
   /**
    * The manager to be used for instantiating plugins.
    *
    * @var \Drupal\Component\Plugin\PluginManagerInterface
    */
-  protected $manager;
+  protected PluginManagerInterface $manager;
 
   /**
    * Constructs a new AuthProvider route subscriber.
@@ -32,7 +35,7 @@ public function __construct(PluginManagerInterface $manager) {
   /**
    * {@inheritdoc}
    */
-  public static function create(ContainerInterface $container) {
+  public static function create(ContainerInterface $container): static {
     return new static(
       $container->get('plugin.manager.os2web_datalookup')
     );
@@ -41,19 +44,20 @@ public static function create(ContainerInterface $container) {
   /**
    * Provides route definition for AuthProvider plugins settings form.
    *
-   * @return array
+   * @return array<string, mixed>
    *   Array with route definitions.
    */
-  public function routes() {
+  public function routes(): array {
     $pluginDefinitions = $this->manager->getDefinitions();
     $routes = [];
     $groups = [];
 
     foreach ($pluginDefinitions as $id => $plugin) {
       $routes["os2web_datalookup.$id"] = new Route(
-        "/admin/config/system/os2web-datalookup/" . str_replace('_', '-', $plugin['id']), [
+        "/admin/config/system/os2web-datalookup/" . str_replace('_', '-', $plugin['id']),
+        [
           '_form' => '\Drupal\os2web_datalookup\Form\DataLookupPluginSettingsForm',
-          '_title' => t("Configure :label", [':label' => $plugin['label']->__toString()])->__toString(),
+          '_title' => $this->t("Configure :label", [':label' => $plugin['label']->__toString()])->__toString(),
           '_plugin_id' => $id,
         ],
         [
@@ -68,11 +72,12 @@ public function routes() {
     // Creating routes for group configuration.
     foreach ($groups as $group) {
       $routes["os2web_datalookup.groups.$group"] = new Route(
-        "/admin/config/system/os2web-datalookup/" . str_replace('_', '-', $group), [
-        '_form' => '\Drupal\os2web_datalookup\Form\DataLookupPluginGroupSettingsForm',
-        '_title' => t("Configure group :label", [':label' => $group])->__toString(),
-        '_group_id' => $group,
-      ],
+        "/admin/config/system/os2web-datalookup/" . str_replace('_', '-', $group),
+        [
+          '_form' => '\Drupal\os2web_datalookup\Form\DataLookupPluginGroupSettingsForm',
+          '_title' => $this->t("Configure group :label", [':label' => $group])->__toString(),
+          '_group_id' => $group,
+        ],
         [
           '_permission' => 'administer os2web datalookup configuration',
         ]