diff --git a/.github/workflows/run-tests.yml b/.github/workflows/run-tests.yml
index ca4f475..d6493d7 100644
--- a/.github/workflows/run-tests.yml
+++ b/.github/workflows/run-tests.yml
@@ -9,7 +9,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        php: ['8.2', '8.3']
+        php: ['8.2', '8.3', '8.4']
         composer-flags: ['--prefer-stable']
         can-fail: [false]
         include:
diff --git a/composer.json b/composer.json
index 3fe3f5c..70d86ca 100644
--- a/composer.json
+++ b/composer.json
@@ -9,7 +9,7 @@
     ],
     "license": "MIT",
     "require": {
-        "php": "8.2.* || 8.3.*",
+        "php": "8.2.* || 8.3.* || 8.4.*",
         "guzzlehttp/psr7": "^2.4",
         "psr/http-message": "^1.0 || ^2.0",
         "ratchet/rfc6455": "^0.3.1",