diff --git a/src/Exception/InvalidArgumentException.php b/src/Exception/InvalidArgumentException.php
new file mode 100644
index 0000000..055ef53
--- /dev/null
+++ b/src/Exception/InvalidArgumentException.php
@@ -0,0 +1,14 @@
+<?php
+namespace Pluf\Core\Exception;
+
+use Pluf\Orm\Attribute\Entity;
+use Pluf\Orm\Attribute\Column;
+use Pluf\Orm\Attribute\Transients;
+use Throwable;
+
+#[Entity]
+#[Transients(["line", "file", "string", "trace", "previous"])]
+class InvalidArgumentException extends \Pluf\Core\Exception
+{
+}
+
diff --git a/src/Exception/InvalidBodyContentException.php b/src/Exception/InvalidBodyContentException.php
index 3128e43..b28cd49 100644
--- a/src/Exception/InvalidBodyContentException.php
+++ b/src/Exception/InvalidBodyContentException.php
@@ -1,6 +1,13 @@
 <?php
 namespace Pluf\Core\Exception;
 
+use Pluf\Orm\Attribute\Entity;
+use Pluf\Orm\Attribute\Column;
+use Pluf\Orm\Attribute\Transients;
+use Throwable;
+
+#[Entity]
+#[Transients(["line", "file", "string", "trace", "previous"])]
 class InvalidBodyContentException extends \Pluf\Core\Exception
 {
 }
diff --git a/src/Exception/NotSupportedMethodException.php b/src/Exception/NotSupportedMethodException.php
new file mode 100644
index 0000000..6f3f71f
--- /dev/null
+++ b/src/Exception/NotSupportedMethodException.php
@@ -0,0 +1,14 @@
+<?php
+namespace Pluf\Core\Exception;
+
+use Pluf\Orm\Attribute\Entity;
+use Pluf\Orm\Attribute\Column;
+use Pluf\Orm\Attribute\Transients;
+use Throwable;
+
+#[Entity]
+#[Transients(["line", "file", "string", "trace", "previous"])]
+class NotSupportedMethodException extends \Pluf\Core\Exception
+{
+}
+
diff --git a/src/Exception/ResourceNotFoundException.php b/src/Exception/ResourceNotFoundException.php
index 9d2f15b..5bf55fb 100644
--- a/src/Exception/ResourceNotFoundException.php
+++ b/src/Exception/ResourceNotFoundException.php
@@ -1,8 +1,14 @@
 <?php
 namespace Pluf\Core\Exception;
 
+
+use Pluf\Orm\Attribute\Entity;
+use Pluf\Orm\Attribute\Column;
+use Pluf\Orm\Attribute\Transients;
 use Throwable;
 
+#[Entity]
+#[Transients(["line", "file", "string", "trace", "previous"])]
 class ResourceNotFoundException extends \Pluf\Core\Exception
 {
 
diff --git a/src/Exception/UnhandledException.php b/src/Exception/UnhandledException.php
index 02f3e5e..8d4439e 100644
--- a/src/Exception/UnhandledException.php
+++ b/src/Exception/UnhandledException.php
@@ -1,8 +1,13 @@
 <?php
 namespace Pluf\Core\Exception;
 
+use Pluf\Orm\Attribute\Entity;
+use Pluf\Orm\Attribute\Column;
+use Pluf\Orm\Attribute\Transients;
 use Throwable;
 
+#[Entity]
+#[Transients(["line", "file", "string", "trace", "previous"])]
 class UnhandledException extends \Pluf\Core\Exception
 {
     
diff --git a/src/Process/Entity/CreateEntities.php b/src/Process/Entity/CreateEntities.php
new file mode 100644
index 0000000..a85d80d
--- /dev/null
+++ b/src/Process/Entity/CreateEntities.php
@@ -0,0 +1,40 @@
+<?php
+namespace Pluf\Core\Process\Entity;
+
+use Pluf\Orm\EntityManager;
+
+/**
+ * Creates a list of customer and return them as result
+ *
+ *
+ * @author maso
+ *        
+ */
+class CreateEntities
+{
+
+    /**
+     * Store list of cusomers into the repositoer
+     *
+     *
+     * @param EntityManager $entityManager
+     * @param array $customers
+     *            list of customer
+     * @return mixed[] list of entities to persist
+     */
+    public function __invoke(EntityManager $entityManager, $entities): array
+    {
+        if (! is_array($entities)) {
+            $entities = [
+                $entities
+            ];
+        }
+        $resultList = [];
+        foreach ($entities as $customer) {
+            $item = $entityManager->persist​($customer);
+            $resultList[] = $item;
+        }
+        return $resultList;
+    }
+}
+
diff --git a/src/Process/Entity/EntityManagerFactory.php b/src/Process/Entity/EntityManagerFactory.php
new file mode 100644
index 0000000..3118abb
--- /dev/null
+++ b/src/Process/Entity/EntityManagerFactory.php
@@ -0,0 +1,21 @@
+<?php
+namespace Pluf\Core\Process\Entity;
+
+use Pluf\Scion\UnitTrackerInterface;
+
+class EntityManagerFactory
+{
+
+    public function __invoke(\Pluf\Orm\EntityManagerFactory $entityManagerFactory, UnitTrackerInterface $unitTracker)
+    {
+        $entityManager = $entityManagerFactory->createEntityManager();
+        try {
+            return $unitTracker->next([
+                "entityManager" => $entityManager
+            ]);
+        } finally {
+            $entityManager->close();
+        }
+    }
+}
+
diff --git a/src/Process/Entity/EntityManagerTransaction.php b/src/Process/Entity/EntityManagerTransaction.php
new file mode 100644
index 0000000..c68c36c
--- /dev/null
+++ b/src/Process/Entity/EntityManagerTransaction.php
@@ -0,0 +1,27 @@
+<?php
+namespace Pluf\Core\Process\Entity;
+
+use Pluf\Scion\UnitTrackerInterface;
+use Throwable;
+use Pluf\Orm\EntityManager;
+
+class EntityManagerTransaction
+{
+
+    public function __invoke(EntityManager $entityManager, UnitTrackerInterface $unitTracker)
+    {
+        $transaction = $entityManager->getTransaction();
+        $transaction->begin();
+        try {
+            $result = $unitTracker->next([
+                "entityManager" => $entityManager
+            ]);
+            $transaction->commit();
+            return $result;
+        } catch (Throwable $th) {
+            $transaction->rollback();
+            throw $th;
+        }
+    }
+}
+
diff --git a/src/Process/Entity/ReadEntities.php b/src/Process/Entity/ReadEntities.php
new file mode 100644
index 0000000..b95e70a
--- /dev/null
+++ b/src/Process/Entity/ReadEntities.php
@@ -0,0 +1,35 @@
+<?php
+namespace Pluf\Core\Process\Entity;
+
+use Pluf\Orm\AssertionTrait;
+use Pluf\Orm\EntityQuery;
+
+class ReadEntities
+{
+    use AssertionTrait;
+    
+    private string $class;
+    private string $name = "entities";
+    
+    public function __construct(string $class, string $name = "entities")
+    {
+        $this->class = $class;
+        $this->name = $name;
+    }
+    
+    /**
+     * Store list of cusomers into the repositoer
+     *
+     *
+     * @param EntityQuery $entityQuery to perform on entities
+     * @return array of results
+     */
+    public function __invoke(EntityQuery $entityQuery): array
+    {
+        return $entityQuery->entity($this->class)
+            ->mode('select')
+            ->exec();
+    }
+        
+}
+
diff --git a/src/Process/Http/RequestToEntityQuery.php b/src/Process/Http/RequestToEntityQuery.php
new file mode 100644
index 0000000..e239ca8
--- /dev/null
+++ b/src/Process/Http/RequestToEntityQuery.php
@@ -0,0 +1,27 @@
+<?php
+namespace Pluf\Core\Process\Http;
+
+use Pluf\Orm\EntityManager;
+use Pluf\Scion\UnitTrackerInterface;
+use Psr\Http\Message\ServerRequestInterface;
+
+/**
+ * Creates an entity query based on http request
+ * 
+ * NOTE: the class must set.
+ * 
+ * @author maso
+ *
+ */
+class RequestToEntityQuery
+{
+    public function __invoke(ServerRequestInterface $request, EntityManager $entityManager, UnitTrackerInterface $unitTracker)
+    {
+        $entityQuery = $entityManager->createQuery();
+        //XXX: maso, 2021: read params from the request header.
+        return $unitTracker->next([
+            'entityQuery' => $entityQuery
+        ]);
+    }
+}
+
diff --git a/src/Process/Http/ResponseBodyEncoder.php b/src/Process/Http/ResponseBodyEncoder.php
index 5538ffe..ee6afd9 100644
--- a/src/Process/Http/ResponseBodyEncoder.php
+++ b/src/Process/Http/ResponseBodyEncoder.php
@@ -44,20 +44,10 @@ public function __invoke(
         try {
             $result = $unitTracker->next();
         } catch (Throwable $t) {
-            if (! ($t instanceof Exception)) {
-                $ex = new Exception\UnhandledException(
-                    message: $t->getMessage(), 
-                    previous: $t);
-            } else {
-                $ex = $t;
-            }
-            $status = $ex->getStatus();
-            // TODO: maso, 2021: enable exception json annotations
-            $result = [
-                'message' => $t->getMessage()
-            ];
+            $result = $this->convertToSerializable($t);
+            $status = $result->getStatus();
         }
-
+        
         // TODO: maso, 2021: support objectMapper
         // $supportMime = $request->getHeader("Accepted");
         $contentType = 'application/json';
@@ -67,5 +57,29 @@ public function __invoke(
             ->withHeader("Content-Type", $contentType)
             ->withBody($streamFactory->createStream($resultEncode));
     }
+    
+    public function convertToSerializable(Throwable $t){
+        if ($t instanceof Exception) {
+            return $t;
+        }
+        $message = $t->getMessage();
+        $params = [];
+        $solutions = [];
+        $previous = $t;
+        if($t instanceof \Pluf\Orm\Exception){
+            $params = $t->getParams();
+            $solutions = $t->getSolutions();
+        } else if($t instanceof \atk4\core\Exception){
+            $params = $t->getParams();
+            $solutions = $t->getSolutions();
+        }
+        return new Exception\UnhandledException(
+            status: 500,
+            code: $t->getCode(),
+            message: $t->getMessage(),
+            params: $params,
+            previous: $previous,
+            solutions: $solutions);
+    }
 }
 
diff --git a/src/Process/HttpBodyToEntities.php b/src/Process/HttpBodyToEntities.php
new file mode 100644
index 0000000..cc9107d
--- /dev/null
+++ b/src/Process/HttpBodyToEntities.php
@@ -0,0 +1,88 @@
+<?php
+namespace Pluf\Core\Process;
+
+use Pluf\Orm\ModelDescriptionRepository;
+use Pluf\Orm\ObjectMapperBuilder;
+use Pluf\Scion\UnitTrackerInterface;
+use Psr\Http\Message\ServerRequestInterface;
+use Pluf\Orm\AssertionTrait;
+
+class HttpBodyToEntities
+{
+    use AssertionTrait;
+
+    private string $class;
+    private bool $multi;
+    private string $name = "entities";
+
+    public function __construct(string $class, bool $multi = true, string $name = "entities")
+    {
+        $this->class = $class;
+        $this->multi = $multi;
+        $this->name = $name;
+    }
+
+    public function __invoke(
+        ModelDescriptionRepository $modelDescriptionRepository, 
+        ServerRequestInterface $request, 
+        UnitTrackerInterface $unitTracker)
+    {
+        $this->assertEquals("POST", $request->getMethod(), "Unsupported method {{method}}", ["method" => $request->getMethod()]);
+
+        $type = $this->getContentType($request);
+        $this->assertNotEmpty($type, "Content type is not specified.");
+        switch ($type) {
+            case "json":
+                $data = $request->getBody();
+                break;
+            case "array":
+            default:
+                $data = $request->getParsedBody();
+                break;
+        }
+
+        $builder = new ObjectMapperBuilder();
+        $objectMapper = $builder->addType($type)
+            ->setModelDescriptionRepository($modelDescriptionRepository)
+            ->supportList($this->multi)
+            ->build();
+        
+        $res = [];
+        $res[$this->name] = $objectMapper->readValue($data, $this->class, $this->multi);
+        return $unitTracker->next($res);
+    }
+
+    public function getContentType(ServerRequestInterface $request): string
+    {
+        $contentTypes = $request->getHeader("Content-Type") ?? [];
+
+        $parsedContentType = 'application/json';
+        foreach ($contentTypes as $contentType) {
+            $fragments = explode(';', $contentType);
+            $parsedContentType = current($fragments);
+        }
+        $contentTypesWithParsedBodies = [
+            'application/json',
+            'application/xml',
+            'application/yml'
+        ];
+
+        $type = null;
+        if (in_array($parsedContentType, $contentTypesWithParsedBodies)) {
+            switch ($parsedContentType) {
+                case 'application/json':
+                    $type = "json";
+                    break;
+                case 'application/xml':
+                case 'application/yml':
+                default:
+                    $type = null;
+            }
+        } else {
+            $type = "array";
+        }
+
+        return $type;
+    }
+}
+