diff --git a/src/EntityTrait.php b/src/EntityTrait.php
index fabd579..f071ea7 100644
--- a/src/EntityTrait.php
+++ b/src/EntityTrait.php
@@ -14,7 +14,7 @@ trait EntityTrait
 {
     use ObjectTrait;
 
-    public function __construct(Model $model, string $id, ?stdClass $data = null)
+    final public function __construct(Model $model, string $id, ?stdClass $data = null)
     {
         $this->model = $model;
         $this->data = $data;
@@ -24,7 +24,7 @@ public function __construct(Model $model, string $id, ?stdClass $data = null)
         $this->data->id = $id;
     }
 
-    public function __set($name, $value) : void
+    final public function __set($name, $value) : void
     {
         if ($name === 'id') {
             throw new OverridingIdentityOfEntityException('You can not change the "id" of an entity!');
@@ -35,12 +35,12 @@ public function __set($name, $value) : void
         $this->data->{$name} = $value;
     }
 
-    public function __unset($name)
+    final public function __unset($name)
     {
         unset($this->data->{$name});
     }
 
-    public static function createFromJsonFile(string $jsonFilePath, string $id) : EntityInterface
+    final public static function createFromJsonFile(string $jsonFilePath, string $id) : EntityInterface
     {
         if (!file_exists($jsonFilePath)) {
             throw new CouldNotFindJSONSchemaFileException(
@@ -51,17 +51,17 @@ public static function createFromJsonFile(string $jsonFilePath, string $id) : En
         return self::createFromJson($json, $id);
     }
 
-    public static function createFromJson(string $json, string $id) : EntityInterface
+    final public static function createFromJson(string $json, string $id) : EntityInterface
     {
-        return new self(new Model($json), $id);
+        return new static(new Model($json), $id);
     }
 
-    public function entityId() : string
+    final public function entityId() : string
     {
         return $this->data->id;
     }
 
-    public function validatePartially(array $requiredFields) : bool
+    final public function validatePartially(array $requiredFields) : bool
     {
         $model = $this->model->getModel();
         $model->required = $requiredFields;
diff --git a/src/ObjectTrait.php b/src/ObjectTrait.php
index 8bb47f5..8bbc948 100644
--- a/src/ObjectTrait.php
+++ b/src/ObjectTrait.php
@@ -19,12 +19,12 @@ trait ObjectTrait
      */
     private $data;
 
-    public function __get($name)
+    final public function __get($name)
     {
         return $this->data->{$name};
     }
 
-    public function __isset($name) : bool
+    final public function __isset($name) : bool
     {
         return property_exists($this->data, $name);
     }
@@ -60,7 +60,7 @@ public function equals($rightHandedObject) : bool
         return (string) json_encode($this->data) === (string) json_encode($rightHandedObject);
     }
 
-    public function jsonSerialize() : stdClass
+    final public function jsonSerialize() : stdClass
     {
         return $this->data;
     }
diff --git a/src/ValueObjectBuilder.php b/src/ValueObjectBuilder.php
index 4eda85f..ef1399e 100644
--- a/src/ValueObjectBuilder.php
+++ b/src/ValueObjectBuilder.php
@@ -9,7 +9,7 @@
 use Selami\Entity\Exception\InvalidMethodNameException;
 use function in_array;
 
-class ValueObjectBuilder
+final class ValueObjectBuilder
 {
     private $jsonSchema;
     private $properties;
diff --git a/src/ValueObjectTrait.php b/src/ValueObjectTrait.php
index 79ef857..001adfe 100644
--- a/src/ValueObjectTrait.php
+++ b/src/ValueObjectTrait.php
@@ -12,7 +12,7 @@ trait ValueObjectTrait
 {
     use ObjectTrait;
 
-    public function __construct(Model $model, stdClass $data)
+    final public function __construct(Model $model, stdClass $data)
     {
         $this->model = $model;
         $this->data = $data;
@@ -29,7 +29,7 @@ final public function __unset($name)
         throw new BadMethodCallException('Can\'t manipulate Immutable Object');
     }
 
-    public static function createFromJsonFile(string $filePath, stdClass $data) : ValueObjectInterface
+    final public static function createFromJsonFile(string $filePath, stdClass $data) : ValueObjectInterface
     {
         if (!file_exists($filePath)) {
             throw new InvalidArgumentException(sprintf('Model definition file (%s) does not exist!', $filePath));
@@ -38,8 +38,8 @@ public static function createFromJsonFile(string $filePath, stdClass $data) : Va
         return self::createFromJson($json, $data);
     }
 
-    public static function createFromJson(string $json, stdClass $data) : ValueObjectInterface
+    final public static function createFromJson(string $json, stdClass $data) : ValueObjectInterface
     {
-        return new self(new Model($json), $data);
+        return new static(new Model($json), $data);
     }
 }