diff --git a/.gitignore b/.gitignore
index cc77e3f..0d42bb7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -17,3 +17,4 @@ Thumbs.db
 
 /vendor/
 composer.lock
+.phpunit.result.cache
diff --git a/composer.json b/composer.json
index ebe76bc..f743517 100644
--- a/composer.json
+++ b/composer.json
@@ -28,6 +28,8 @@
     "symfony/messenger": "^4.4"
   },
   "require-dev": {
-    "pccomponentes/coding-standard": "^1.0"
+    "pccomponentes/coding-standard": "^1.0",
+    "phpunit/phpunit": "^8.5",
+    "dg/bypass-finals": "^1.1"
   }
 }
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
new file mode 100644
index 0000000..0418ea8
--- /dev/null
+++ b/phpunit.xml.dist
@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<!-- https://phpunit.de/manual/current/en/appendixes.configuration.html -->
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/6.5/phpunit.xsd"
+         backupGlobals="false"
+         colors="true"
+         bootstrap="tests/bootstrap.php"
+>
+    <php>
+        <ini name="error_reporting" value="-1" />
+        <server name="APP_ENV" value="test" force="true" />
+        <server name="SHELL_VERBOSITY" value="-1" />
+    </php>
+
+    <testsuites>
+        <testsuite name="Project Test Suite">
+            <directory>tests</directory>
+        </testsuite>
+    </testsuites>
+
+    <filter>
+        <whitelist>
+            <directory suffix=".php">src</directory>
+        </whitelist>
+    </filter>
+</phpunit>
diff --git a/src/Driver/TransactionalConnection.php b/src/Driver/TransactionalConnection.php
index be81910..268d20d 100644
--- a/src/Driver/TransactionalConnection.php
+++ b/src/Driver/TransactionalConnection.php
@@ -5,7 +5,7 @@
 
 interface TransactionalConnection
 {
-    public function beginTransaction(): bool;
-    public function commit(): bool;
-    public function rollBack(): bool;
+    public function beginTransaction(): void;
+    public function commit(): void;
+    public function rollBack(): void;
 }
diff --git a/src/Driver/TransactionalConnections.php b/src/Driver/TransactionalConnections.php
deleted file mode 100644
index 7ac919a..0000000
--- a/src/Driver/TransactionalConnections.php
+++ /dev/null
@@ -1,47 +0,0 @@
-<?php
-declare(strict_types=1);
-
-namespace PcComponentes\Transaction\Driver;
-
-final class TransactionalConnections implements \Iterator
-{
-    private array $connections;
-
-    public function __construct(TransactionalConnection ...$connections)
-    {
-        $this->connections = $connections;
-    }
-
-    public function current(): ?TransactionalConnection
-    {
-        $connection = \current($this->connections);
-        if (false === $connection) {
-            return null;
-        }
-
-        return $connection;
-    }
-
-    public function next()
-    {
-        \next($this->connections);
-    }
-
-    public function key()
-    {
-        return \key($this->connections);
-    }
-
-    public function valid(): bool
-    {
-        return \array_key_exists(
-            $this->key(),
-            $this->connections
-        );
-    }
-
-    public function rewind()
-    {
-        \reset($this->connections);
-    }
-}
diff --git a/src/SymfonyMessenger/TransactionMiddleware.php b/src/SymfonyMessenger/TransactionMiddleware.php
index fa15974..5fdda96 100644
--- a/src/SymfonyMessenger/TransactionMiddleware.php
+++ b/src/SymfonyMessenger/TransactionMiddleware.php
@@ -3,52 +3,32 @@
 
 namespace PcComponentes\Transaction\SymfonyMessenger;
 
+use PcComponentes\Transaction\Driver\TransactionalConnection;
 use Symfony\Component\Messenger\Envelope;
 use Symfony\Component\Messenger\Middleware\StackInterface;
-use PcComponentes\Transaction\Driver\TransactionalConnections;
 use Symfony\Component\Messenger\Middleware\MiddlewareInterface;
 
 final class TransactionMiddleware implements MiddlewareInterface
 {
-    private TransactionalConnections $connections;
+    private TransactionalConnection $connection;
 
-    public function __construct(TransactionalConnections $connections)
+    public function __construct(TransactionalConnection $connection)
     {
-        $this->connections = $connections;
+        $this->connection = $connection;
     }
+
     public function handle(Envelope $envelope, StackInterface $stack): Envelope
     {
         try {
-            $this->beginTransaction();
+            $this->connection->beginTransaction();
             $envelope = $stack->next()->handle($envelope, $stack);
-            $this->commit();
+            $this->connection->commit();
 
             return $envelope;
         } catch (\Throwable $exception) {
-            $this->rollBack();
+            $this->connection->rollBack();
 
             throw $exception;
         }
     }
-
-    private function beginTransaction(): void
-    {
-        foreach ($this->connections as $connection) {
-            $connection->beginTransaction();
-        }
-    }
-
-    private function commit(): void
-    {
-        foreach ($this->connections as $connection) {
-            $connection->commit();
-        }
-    }
-
-    private function rollBack(): void
-    {
-        foreach ($this->connections as $connection) {
-            $connection->rollBack();
-        }
-    }
 }
diff --git a/tests/SymfonyMessenger/TransactionMiddlewareTest.php b/tests/SymfonyMessenger/TransactionMiddlewareTest.php
new file mode 100644
index 0000000..33151bc
--- /dev/null
+++ b/tests/SymfonyMessenger/TransactionMiddlewareTest.php
@@ -0,0 +1,110 @@
+<?php
+declare(strict_types=1);
+
+namespace PcComponentes\Transaction\Tests\SymfonyMessenger;
+
+use PcComponentes\Transaction\Driver\TransactionalConnection;
+use PcComponentes\Transaction\SymfonyMessenger\TransactionMiddleware;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Messenger\Envelope;
+use Symfony\Component\Messenger\Middleware\MiddlewareInterface;
+use Symfony\Component\Messenger\Middleware\StackInterface;
+
+final class TransactionMiddlewareTest extends TestCase
+{
+    /**
+     * @test
+     */
+    public function given_transactional_connection_when_handle_then_begin_transaction_and_commit()
+    {
+        $transactionalConnection = $this->createMock(TransactionalConnection::class);
+
+        $transactionalConnection
+            ->expects($this->once())
+            ->method('beginTransaction')
+        ;
+        $transactionalConnection
+            ->expects($this->once())
+            ->method('commit')
+        ;
+
+        $transactionMiddleware = new TransactionMiddleware($transactionalConnection);
+        $transactionMiddleware->handle(
+            $this->createMock(Envelope::class),
+            $this->createMock(StackInterface::class)
+        );
+    }
+
+    /**
+     * @test
+     */
+    public function given_envelope_and_stack_with_next_middleware_when_handle_then_go_forward_to_next_middleware_and_execute_it()
+    {
+        $envelope = $this->createMock(Envelope::class);
+        $nextMiddleware = $this->createMock(MiddlewareInterface::class);
+        $stack = $this->createMock(StackInterface::class);
+
+        $stack
+            ->expects($this->once())
+            ->method('next')
+            ->willReturn($nextMiddleware)
+        ;
+        $nextMiddleware
+            ->expects($this->once())
+            ->method('handle')
+            ->with($envelope, $stack)
+            ->willReturn($envelope)
+        ;
+
+        $transactionMiddleware = new TransactionMiddleware(
+            $this->createMock(TransactionalConnection::class)
+        );
+        $transactionMiddleware->handle(
+            $envelope,
+            $stack
+        );
+    }
+
+    /**
+     * @test
+     */
+    public function given_next_middleware_throwing_exception_when_handle_then_rollback_transaction_and_throw_catch_exception()
+    {
+        $transactionalConnection = $this->createMock(TransactionalConnection::class);
+        $nextMiddleware = $this->createMock(MiddlewareInterface::class);
+        $stack = $this->createMock(StackInterface::class);
+        $exception = new class extends \Exception {};
+
+        $transactionalConnection
+            ->expects($this->once())
+            ->method('beginTransaction')
+        ;
+        $stack
+            ->expects($this->once())
+            ->method('next')
+            ->willReturn($nextMiddleware)
+        ;
+        $nextMiddleware
+            ->expects($this->once())
+            ->method('handle')
+            ->willThrowException($exception)
+        ;
+        $transactionalConnection
+            ->expects($this->never())
+            ->method('commit')
+        ;
+        $transactionalConnection
+            ->expects($this->once())
+            ->method('rollback')
+        ;
+        $this->expectException(
+            \get_class($exception)
+        );
+
+        $transactionMiddleware = new TransactionMiddleware($transactionalConnection);
+        $transactionMiddleware->handle(
+            $this->createMock(Envelope::class),
+            $stack
+        );
+    }
+}
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
new file mode 100644
index 0000000..6bd210f
--- /dev/null
+++ b/tests/bootstrap.php
@@ -0,0 +1,6 @@
+<?php
+declare(strict_types=1);
+
+require dirname(__DIR__).'/vendor/autoload.php';
+
+\DG\BypassFinals::enable();