diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 52ad3f0..4a7ce2b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,6 +11,7 @@ jobs:
     strategy:
       matrix:
         php:
+          - 8.3
           - 8.2
           - 8.1
           - 8.0
@@ -23,7 +24,7 @@ jobs:
           - 5.5
           - 5.4
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: shivammathur/setup-php@v2
         with:
           php-version: ${{ matrix.php }}
diff --git a/composer.json b/composer.json
index 604c2ab..4b12f2c 100644
--- a/composer.json
+++ b/composer.json
@@ -18,7 +18,7 @@
         "react/promise": "^3 || ^2.10 || ^1.2.1"
     },
     "require-dev": {
-        "phpunit/phpunit": "^9.6 || ^5.7 || ^4.8.35"
+        "phpunit/phpunit": "^9.6 || ^5.7 || ^4.8.36"
     },
     "autoload": {
         "psr-4": {