diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 70f04c7..46c5aa3 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -14,7 +14,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        php: [8.3, 8.2, 8.1]
+        php: [8.4, 8.3, 8.2, 8.1]
         dependency-version: [prefer-lowest, prefer-stable]
 
     name: PHP${{ matrix.php }} - ${{ matrix.dependency-version }}
diff --git a/composer.json b/composer.json
index 1f4532c..e78dd3d 100644
--- a/composer.json
+++ b/composer.json
@@ -26,7 +26,7 @@
     "phpunit/phpunit": "^10.5",
     "guzzlehttp/guzzle": "^7.8",
     "friendsofphp/php-cs-fixer": "^3.57",
-    "vimeo/psalm": "^5.24",
+    "vimeo/psalm": "^6.0",
     "psalm/plugin-phpunit": "^0.19",
     "phpstan/phpstan": "^2.0"
   },