diff --git a/app/Lib/Axepta/AxeptaConfig.php b/app/Lib/Axepta/AxeptaConfig.php
new file mode 100644
index 00000000..c29f324a
--- /dev/null
+++ b/app/Lib/Axepta/AxeptaConfig.php
@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Lib\Axepta;
+
+final readonly class AxeptaConfig
+{
+    public function __construct(
+        #[\SensitiveParameter]
+        public string $endpoint,
+        #[\SensitiveParameter]
+        public string $merchantId,
+        #[\SensitiveParameter]
+        public string $apiKey,
+        #[\SensitiveParameter]
+        public string $hmac,
+        /** @param array<string,mixed> $axeptaConfig */
+        #[\SensitiveParameter]
+        public array $checkoutConfig = []
+    ) {
+        if (empty(trim($endpoint))) {
+            throw new \DomainException('Endpoint cannot be empty');
+        }
+        if (empty(trim($merchantId))) {
+            throw new \DomainException('Merchant ID cannot be empty');
+        }
+        if (empty(trim($apiKey))) {
+            throw new \DomainException('API Key cannot be empty');
+        }
+        if (empty(trim($hmac))) {
+            throw new \DomainException('HMAC cannot be empty');
+        }
+    }
+}
diff --git a/app/Lib/Axepta/AxeptaPayment.php b/app/Lib/Axepta/AxeptaPayment.php
index 8b7b8f87..d46e58c3 100644
--- a/app/Lib/Axepta/AxeptaPayment.php
+++ b/app/Lib/Axepta/AxeptaPayment.php
@@ -21,15 +21,13 @@ class AxeptaPayment
 
     /**
      * Guzzle Client instance
-     *
-     * @var GuzzleHttp\Client
      */
     private \GuzzleHttp\Client $client;
 
     /**
      * Additionnal or Update Axepta configuration
      *
-     * @var array
+     * @var array<string,mixed>
      */
     private array $axeptaCheckoutConfig;
 
@@ -40,35 +38,12 @@ class AxeptaPayment
      */
     private string $cacheKey = "AxeptaBearerToken";
 
-    /**
-     * Construct method
-     *
-     * @param string $endpoint     Axepta Endpoint
-     * @param string $merchantId   Axepta Merchant ID
-     * @param string $apiKey       Axepta Secret API Key
-     * @param string $hmac         Axepta HMAC
-     * @param array  $axeptaConfig Additionnal or Update Axepta configuration
-     * @return void
-     */
     public function __construct(
         private readonly LoggerInterface $logger,
-        #[\SensitiveParameter]
-        private string $endpoint,
-        #[\SensitiveParameter]
-        private string $merchantId,
-        #[\SensitiveParameter]
-        private string $apiKey,
-        #[\SensitiveParameter]
-        private string $hmac,
-        #[\SensitiveParameter]
-        private array $axeptaConfig = []
+        private readonly AxeptaConfig $axeptaConfig
     ) {
-        $this->endpoint             = $endpoint;
-        $this->merchantId           = $merchantId;
-        $this->apiKey               = $apiKey;
-        $this->hmac                 = $hmac;
-        $this->client               = new Client([
-            'base_uri' => $this->endpoint,
+        $this->client = new Client([
+            'base_uri' => $this->axeptaConfig->endpoint,
             'timeout'  => 5.0,
         ]);
         $this->axeptaCheckoutConfig = [
@@ -89,7 +64,7 @@ class AxeptaPayment
                     ],
                 ]
             ],
-            ...$axeptaConfig
+            ...$axeptaConfig->checkoutConfig
         ];
     }
 
@@ -110,8 +85,8 @@ class AxeptaPayment
             $response = $this->client->post('/authorization/oauth/token', [
                 'form_params' => [
                     'grant_type' => 'client_credentials',
-                    'client_id' => $this->merchantId,
-                    'client_secret' => $this->apiKey
+                    'client_id' => $this->axeptaConfig->merchantId,
+                    'client_secret' => $this->axeptaConfig->apiKey
                 ]
             ]);
 
@@ -145,8 +120,12 @@ class AxeptaPayment
      * @return string
      * @throws \RuntimeException
      */
-    public function getCheckoutUrl(AxeptaOrder $order, string $returnUrl, string $cancelUrl, string $webhookUrl): string
-    {
+    public function getCheckoutUrl(
+        #[\SensitiveParameter] AxeptaOrder $order,
+        #[\SensitiveParameter] string $returnUrl,
+        #[\SensitiveParameter]  $cancelUrl,
+        #[\SensitiveParameter] string $webhookUrl
+    ): string {
         $payload = [
             "transId" => $this->generateTransId(),
             "urls" => [
@@ -268,7 +247,8 @@ class AxeptaPayment
         $rawPayload       = $request->getContent(false);
 
         $this->logger->debug(
-            'Received an IPN call', [
+            'Received an IPN call',
+            [
                 'request_signature_version' => $signatureVersion,
                 'request_signature'         => $signature,
                 'request_timestamp'         => $timestamp,
@@ -347,8 +327,11 @@ class AxeptaPayment
      * @param string                  $rawPayload
      * @return boolean
      */
-    private function isValidSignature(string $signature, CarbonInterface $timestamp, string $rawPayload): bool
-    {
+    private function isValidSignature(
+        #[\SensitiveParameter] string $signature,
+        CarbonInterface $timestamp,
+        #[\SensitiveParameter] string $rawPayload
+    ): bool {
         $providedSignature = $this->extractSignatureFromCurrentVersion($signature);
 
         if (!$providedSignature) {
@@ -360,7 +343,7 @@ class AxeptaPayment
         }
 
         $signedPayload     = "{$timestamp}.{$rawPayload}";
-        $expectedSignature = hash_hmac('sha256', $signedPayload, $this->hmac);
+        $expectedSignature = hash_hmac('sha256', $signedPayload, $this->axeptaConfig->hmac);
         $signatureIsValid  = hash_equals($expectedSignature, $providedSignature);
 
         if (!$signatureIsValid) {
@@ -386,7 +369,7 @@ class AxeptaPayment
      * @param string $signature
      * @return string|null
      */
-    private function extractSignatureFromCurrentVersion(string $signature): ?string
+    private function extractSignatureFromCurrentVersion(#[\SensitiveParameter] string $signature): ?string
     {
         $signatures         = explode(',', $signature);
         $filteredSignatures = array_filter($signatures, function (string $key) {
diff --git a/tests/Unit/Lib/Axepta/AxeptaConfigTest.php b/tests/Unit/Lib/Axepta/AxeptaConfigTest.php
new file mode 100644
index 00000000..acc87f5c
--- /dev/null
+++ b/tests/Unit/Lib/Axepta/AxeptaConfigTest.php
@@ -0,0 +1,116 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Unit\Lib\Axepta;
+
+use App\Lib\Axepta\AxeptaConfig;
+use DomainException;
+use Tests\TestCase;
+
+class AxeptaConfigTest extends TestCase
+{
+    public function testCanInstanciateAnAxeptaConfig(): void
+    {
+        // GIVEN
+        $endpoint = 'https://api.axepta.com';
+        $merchantId = 'M_123456';
+        $apiKey = 'secret_key_123';
+        $hmac = 'hmac_value_456';
+
+        // WHEN
+        $config = new AxeptaConfig(
+            $endpoint,
+            $merchantId,
+            $apiKey,
+            $hmac
+        );
+
+        // THEN
+        $this->assertInstanceOf(AxeptaConfig::class, $config);
+    }
+
+    public function testCannotInstanciateWithEmptyEndpoint(): void
+    {
+        $this->assertThrows(function () {
+            // GIVEN
+            $endpoint = '';
+            $merchantId = 'M_123';
+            $apiKey = 'key';
+            $hmac = 'hmac';
+
+            // WHEN
+            new AxeptaConfig(
+                $endpoint,
+                $merchantId,
+                $apiKey,
+                $hmac
+            );
+
+            // THEN
+        }, DomainException::class);
+    }
+
+    public function testCannotInstanciateWithEmptyMerchantId(): void
+    {
+        $this->assertThrows(function () {
+            // GIVEN
+            $endpoint = 'https://api.axepta.com';
+            $merchantId = '';
+            $apiKey = 'key';
+            $hmac = 'hmac';
+
+            // WHEN
+            new AxeptaConfig(
+                $endpoint,
+                $merchantId,
+                $apiKey,
+                $hmac
+            );
+
+            // THEN
+        }, DomainException::class);
+    }
+
+    public function testCannotInstanciateWithEmptyApiKey(): void
+    {
+        $this->assertThrows(function () {
+            // GIVEN
+            $endpoint = 'https://api.axepta.com';
+            $merchantId = 'M_123';
+            $apiKey = '';
+            $hmac = 'hmac';
+
+            // WHEN
+            new AxeptaConfig(
+                $endpoint,
+                $merchantId,
+                $apiKey,
+                $hmac
+            );
+
+            // THEN
+        }, DomainException::class);
+    }
+
+    public function testCannotInstanciateWithEmptyHmac(): void
+    {
+        $this->assertThrows(function () {
+            // GIVEN
+            $endpoint = 'https://api.axepta.com';
+            $merchantId = 'M_123';
+            $apiKey = 'key';
+            $hmac = '';
+
+            // WHEN
+            new AxeptaConfig(
+                $endpoint,
+                $merchantId,
+                $apiKey,
+                $hmac
+            );
+
+            // THEN
+        }, DomainException::class);
+    }
+}