diff --git a/webapp/tests/E2E/Controller/ControllerRolesTraversalTest.php b/webapp/tests/E2E/Controller/ControllerRolesTraversalTest.php
index efaf72d0cc..77d6a850bf 100644
--- a/webapp/tests/E2E/Controller/ControllerRolesTraversalTest.php
+++ b/webapp/tests/E2E/Controller/ControllerRolesTraversalTest.php
@@ -53,7 +53,7 @@ protected function roleCombinations(array $start_roles, array $possible_roles):
 
         foreach ($possible_roles as $element) {
             foreach ($results as $combination) {
-                $results[] = array_merge([$element], $combination);
+                $results[] = [$element, ...$combination];
             }
         }
         return $results;
@@ -137,7 +137,7 @@ protected function getAllPages(array $urlsToCheck, string $skip): array
                     continue;
                 }
                 if (!$this->urlExcluded($url, $skip)) {
-                    $urlsToCheck = array_unique(array_merge($urlsToCheck, $this->crawlPageGetLinks($url, 200, $skip)));
+                    $urlsToCheck = array_unique([...$urlsToCheck, ...$this->crawlPageGetLinks($url, 200, $skip)]);
                 }
                 $done[] = $url;
             }
diff --git a/webapp/tests/Unit/Controller/API/AccountBaseTestCase.php b/webapp/tests/Unit/Controller/API/AccountBaseTestCase.php
index c6cdd327a5..2ac0b9b28a 100644
--- a/webapp/tests/Unit/Controller/API/AccountBaseTestCase.php
+++ b/webapp/tests/Unit/Controller/API/AccountBaseTestCase.php
@@ -57,7 +57,7 @@ public function helperVerifyApiUsers(string $myURL, array $objectsBeforeTest, ar
             self::assertEquals(1, count($newItems));
         }
         $listKey = array_keys($newItems)[0];
-        $newUserPostData = array_merge($newUserPostData, (array)$overwritten);
+        $newUserPostData = [...$newUserPostData, ...(array)$overwritten];
         foreach ($newUserPostData as $key => $expectedValue) {
             if ($key !== 'password') {
                 // For security we don't output the password in the API
diff --git a/webapp/tests/Unit/Controller/API/BaseTestCase.php b/webapp/tests/Unit/Controller/API/BaseTestCase.php
index 78645c07ae..49c4636648 100644
--- a/webapp/tests/Unit/Controller/API/BaseTestCase.php
+++ b/webapp/tests/Unit/Controller/API/BaseTestCase.php
@@ -295,7 +295,7 @@ public function testListWithAbsentIds(): void
             fn($id) => $this->resolveReference($id),
             array_keys($this->expectedObjects)
         );
-        $ids = array_merge($expectedObjectIds, $this->expectedAbsent);
+        $ids = [...$expectedObjectIds, ...$this->expectedAbsent];
         $url = $this->helperGetEndpointURL($apiEndpoint);
         $response = $this->verifyApiJsonResponse('GET', $url . "?" . http_build_query(['ids' => $ids]), 404, $this->apiUser);
         static::assertEquals('One or more objects not found', $response['message']);
diff --git a/webapp/tests/Unit/Controller/Jury/JuryControllerTestCase.php b/webapp/tests/Unit/Controller/Jury/JuryControllerTestCase.php
index 57f8007ba5..3d58e4690e 100644
--- a/webapp/tests/Unit/Controller/Jury/JuryControllerTestCase.php
+++ b/webapp/tests/Unit/Controller/Jury/JuryControllerTestCase.php
@@ -456,7 +456,7 @@ public function provideAddCorrectEntities(): Generator
     {
         $entities = static::$addEntities;
         if (!$this->dataSourceIsLocal()) {
-            $entities = array_merge($entities, static::$addEntitiesNonLocal);
+            $entities = [...$entities, ...static::$addEntitiesNonLocal];
         }
         foreach ($entities as $element) {
             [$combinedValues, $element] = $this->helperProvideMergeAddEntity($element);
@@ -469,7 +469,7 @@ public function provideAddFailureEntities(): Generator
     {
         $entities = static::$addEntitiesFailure;
         if (!$this->dataSourceIsLocal()) {
-            $entities = array_merge($entities, static::$addEntitiesFailureNonLocal);
+            $entities = [...$entities, ...static::$addEntitiesFailureNonLocal];
         }
         foreach ($entities as $message => $elementList) {
             foreach ($elementList as $element) {
diff --git a/webapp/tests/Unit/Controller/Jury/JuryMiscControllerTest.php b/webapp/tests/Unit/Controller/Jury/JuryMiscControllerTest.php
index 84263877ab..60096447c8 100644
--- a/webapp/tests/Unit/Controller/Jury/JuryMiscControllerTest.php
+++ b/webapp/tests/Unit/Controller/Jury/JuryMiscControllerTest.php
@@ -115,7 +115,7 @@ public function testBalloonScoreboard(array $fixtures, bool $public, string $con
             $this->verifyPageResponse('HEAD', '/public/problems/'.$id.'/text', $statusCode);
         }
         $this->verifyPageResponse('GET', '/public/problems', 200);
-        if (in_array($contestStage, array_merge(['preStart'], $nonActiveStages)) || !$public) {
+        if (in_array($contestStage, ['preStart', ...$nonActiveStages]) || !$public) {
             self::assertSelectorExists('body:contains("No problem texts available at this point.")');
         } else {
             self::assertSelectorNotExists('body:contains("No problem texts available at this point.")');
diff --git a/webapp/tests/Unit/Controller/PublicControllerTest.php b/webapp/tests/Unit/Controller/PublicControllerTest.php
index 91e60b86ab..c76e7e6859 100644
--- a/webapp/tests/Unit/Controller/PublicControllerTest.php
+++ b/webapp/tests/Unit/Controller/PublicControllerTest.php
@@ -220,7 +220,7 @@ public function selfRegisterProvider(): Generator
                 yield[['username'=>'newinstsamecountry', 'name'=>'CompetingDutchTeam', 'teamName'=>'SupperT3@m','affiliation'=>'new','affiliationName'=>'Vrije Universiteit',
                        'affiliationShortName'=>'vu','affiliationCountry'=>'NLD'],'demo', $fixtures, $category];
                 if (count($fixtures)===1) {
-                    yield[['username'=>'reusevaluesofexistinguser', 'name'=>'selfregistered user for example team','email'=>'electronic@mail.tld','teamName'=>'EasyEnough','affiliation'=>'none'],'demo', array_merge($fixtures, [SelfRegisteredUserFixture::class]),''];
+                    yield[['username'=>'reusevaluesofexistinguser', 'name'=>'selfregistered user for example team','email'=>'electronic@mail.tld','teamName'=>'EasyEnough','affiliation'=>'none'],'demo', [...$fixtures, SelfRegisteredUserFixture::class],''];
                 }
             }
         }
diff --git a/webapp/tests/Unit/Service/ImportExportServiceTest.php b/webapp/tests/Unit/Service/ImportExportServiceTest.php
index be1a9554e4..eb95cbd88c 100644
--- a/webapp/tests/Unit/Service/ImportExportServiceTest.php
+++ b/webapp/tests/Unit/Service/ImportExportServiceTest.php
@@ -542,27 +542,24 @@ protected function testImportAccounts(int $importCount, ?string $message, bool $
             ],
         ];
         if ($forTsv) {
-            $expectedUsers = array_merge($expectedUsers, [
-                [
-                    'roles' => ['team'],
-                    'name' => 'Team 2 user a',
-                    'username' => 'team02a',
-                    'password' => 'password3',
-                    'ip' => '5.6.7.8',
-                    'team' => [
-                        'id' => 2,
-                    ],
+            $expectedUsers = [...$expectedUsers, [
+                'roles' => ['team'],
+                'name' => 'Team 2 user a',
+                'username' => 'team02a',
+                'password' => 'password3',
+                'ip' => '5.6.7.8',
+                'team' => [
+                    'id' => 2,
                 ],
-                [
-                    'roles' => ['team'],
-                    'name' => 'Team 2 user b',
-                    'username' => 'team02b',
-                    'password' => 'password4',
-                    'team' => [
-                        'id' => 2,
-                    ],
+            ], [
+                'roles' => ['team'],
+                'name' => 'Team 2 user b',
+                'username' => 'team02b',
+                'password' => 'password4',
+                'team' => [
+                    'id' => 2,
                 ],
-            ]);
+            ]];
         }
         $unexpectedUsers = ['analyst1', 'analyst2'];