diff --git a/psalm.xml b/psalm.xml
index 28969522651124780bed05d08b421d31dd9e44eb..84000454de27a2d25cc3f09798b41b46210b75a9 100644
--- a/psalm.xml
+++ b/psalm.xml
@@ -22,6 +22,7 @@
         <directory name="modules/saml" />
 
         <directory name="tests" />
+        <directory name="www" />
 
         <!-- Ignore deprecated classes -->
         <ignoreFiles>
diff --git a/www/saml2/idp/ArtifactResolutionService.php b/www/saml2/idp/ArtifactResolutionService.php
index 162937c839a45aad81a1f2a88c4d3b57561feafa..8da7681aeb4fe8eefbf42d087d4fcd94fdcf8f55 100644
--- a/www/saml2/idp/ArtifactResolutionService.php
+++ b/www/saml2/idp/ArtifactResolutionService.php
@@ -47,10 +47,8 @@ if (!($request instanceof \SAML2\ArtifactResolve)) {
 }
 
 $issuer = $request->getIssuer();
-if (!is_string($issuer)) {
-    $issuer = $issuer->getValue();
-}
-
+\Webmozart\Assert\Assert::notNull($issuer);
+$issuer = $issuer->getValue();
 $spMetadata = $metadata->getMetaDataConfig($issuer, 'saml20-sp-remote');
 
 $artifact = $request->getArtifact();
@@ -60,7 +58,7 @@ $store->delete('artifact', $artifact);
 
 if ($responseData !== null) {
     $document = \SAML2\DOMDocumentFactory::fromString($responseData);
-    $responseXML = $document->firstChild;
+    $responseXML = $document->documentElement;
 } else {
     $responseXML = null;
 }
diff --git a/www/saml2/idp/metadata.php b/www/saml2/idp/metadata.php
index 05a1959517fb343c4aca6eea33e363785c8b181e..65fff2da7f8f16a4a6cf5b81362e7bb1699777ea 100644
--- a/www/saml2/idp/metadata.php
+++ b/www/saml2/idp/metadata.php
@@ -200,9 +200,11 @@ try {
 
     $technicalContactEmail = $config->getString('technicalcontact_email', false);
     if ($technicalContactEmail && $technicalContactEmail !== 'na@example.org') {
-        $techcontact['emailAddress'] = $technicalContactEmail;
-        $techcontact['name'] = $config->getString('technicalcontact_name', null);
-        $techcontact['contactType'] = 'technical';
+        $techcontact = [
+            'emailAddress' => $technicalContactEmail,
+            'name' => $config->getString('technicalcontact_name', null),
+            'contactType' => 'technical',
+        ];
         $metaArray['contacts'][] = Metadata::getContact($techcontact);
     }