diff --git a/src/Frontend/AbstractMapHybrid.php b/src/Frontend/AbstractMapHybrid.php
index a69d87f..7344558 100644
--- a/src/Frontend/AbstractMapHybrid.php
+++ b/src/Frontend/AbstractMapHybrid.php
@@ -9,15 +9,17 @@
  *
  */
 
+declare(strict_types=1);
+
 namespace Netzmacht\Contao\Leaflet\Frontend;
 
-use ContaoCommunityAlliance\Translator\TranslatorInterface as Translator;
 use Database\Result;
 use Model\Collection;
 use Netzmacht\Contao\Leaflet\MapProvider;
 use Netzmacht\Contao\Leaflet\Model\MapModel;
 use Netzmacht\Contao\Toolkit\Component\Hybrid\AbstractHybrid;
 use Netzmacht\Contao\Toolkit\View\Template\TemplateFactory;
+use Symfony\Component\Translation\TranslatorInterface as Translator;
 
 /**
  * Class HybridTrait provides method required by the frontend module and content element the same time.
@@ -79,7 +81,7 @@ abstract class AbstractMapHybrid extends AbstractHybrid
      *
      * @return string
      */
-    public function generate()
+    public function generate(): string
     {
         $this->mapProvider->handleAjaxRequest($this->getIdentifier());
 
@@ -113,7 +115,7 @@ abstract class AbstractMapHybrid extends AbstractHybrid
      *
      * @SuppressWarnings(PHPMD.Superglobals)
      */
-    protected function compile()
+    protected function compile(): void
     {
         try {
             $template = $this->get('leaflet_template') ?: 'leaflet_map_js';
@@ -146,5 +148,5 @@ abstract class AbstractMapHybrid extends AbstractHybrid
      *
      * @return string
      */
-    abstract protected function getIdentifier();
+    abstract protected function getIdentifier(): string;
 }
diff --git a/src/Frontend/InsertTag/LeafletInsertTagParser.php b/src/Frontend/InsertTag/LeafletInsertTagParser.php
index fb2c35b..58c53ad 100644
--- a/src/Frontend/InsertTag/LeafletInsertTagParser.php
+++ b/src/Frontend/InsertTag/LeafletInsertTagParser.php
@@ -9,6 +9,8 @@
  *
  */
 
+declare(strict_types=1);
+
 namespace Netzmacht\Contao\Leaflet\Frontend\InsertTag;
 
 use Netzmacht\Contao\Leaflet\MapProvider;
@@ -57,28 +59,20 @@ class LeafletInsertTagParser implements Parser
     /**
      * {@inheritDoc}
      */
-    public static function getTags()
+    public function supports(string $tag): bool
     {
-        return ['leaflet'];
+        return $tag === 'leaflet';
     }
 
     /**
      * {@inheritDoc}
      */
-    public function supports($tag)
-    {
-        return in_array($tag, static::getTags());
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public function parse($raw, $tag, $params = null, $cache = true)
+    public function parse(string $raw, string $tag, string $params = null, bool $cache = true): string
     {
         $parts = explode('::', $params);
 
         if (empty($parts[0])) {
-            return false;
+            return '';
         }
 
         $style    = empty($parts[1]) ? 'width:400px;height:300px' : $parts[1];
@@ -98,7 +92,7 @@ class LeafletInsertTagParser implements Parser
      *
      * @throws \Exception If debug mode is enabled and something went wrong.
      */
-    private function generateMap($mapId, $template, $style)
+    private function generateMap($mapId, string $template, string $style)
     {
         try {
             return $this->mapProvider->generate($mapId, null, $mapId, $template, $style);
diff --git a/src/Frontend/MapElement.php b/src/Frontend/MapElement.php
index 0ae08f1..dc1cdb2 100644
--- a/src/Frontend/MapElement.php
+++ b/src/Frontend/MapElement.php
@@ -9,6 +9,8 @@
  *
  */
 
+declare(strict_types=1);
+
 namespace Netzmacht\Contao\Leaflet\Frontend;
 
 /**
@@ -30,7 +32,7 @@ class MapElement extends AbstractMapHybrid
      *
      * @return string
      */
-    protected function getIdentifier()
+    protected function getIdentifier(): string
     {
         if ($this->get('leaflet_mapId')) {
             return $this->get('leaflet_mapId');
diff --git a/src/Frontend/MapModule.php b/src/Frontend/MapModule.php
index 3819d8e..13b1431 100644
--- a/src/Frontend/MapModule.php
+++ b/src/Frontend/MapModule.php
@@ -9,6 +9,8 @@
  *
  */
 
+declare(strict_types=1);
+
 namespace Netzmacht\Contao\Leaflet\Frontend;
 
 /**
@@ -30,7 +32,7 @@ class MapModule extends AbstractMapHybrid
      *
      * @return string
      */
-    protected function getIdentifier()
+    protected function getIdentifier(): string
     {
         if ($this->get('leaflet_mapId')) {
             return $this->get('leaflet_mapId');