diff --git a/.github/workflows/grumphp.yaml b/.github/workflows/grumphp.yaml
index dfa4f21..c696370 100644
--- a/.github/workflows/grumphp.yaml
+++ b/.github/workflows/grumphp.yaml
@@ -7,7 +7,7 @@ jobs:
         strategy:
             matrix:
                 operating-system: [ubuntu-latest]
-                php-versions: ['8.1', '8.2', '8.3']
+                php-versions: ['8.1', '8.2', '8.3', '8.4']
                 composer-options: ['', '--prefer-lowest']
             fail-fast: false
         name: PHP ${{ matrix.php-versions }} @ ${{ matrix.operating-system }} with ${{ matrix.composer-options }}
@@ -20,6 +20,11 @@ jobs:
                   php-version: ${{ matrix.php-versions }}
                   tools: 'composer:v2'
                   extensions: pcov, mbstring, posix
+            - name: Set env vars for latest PHP version
+              if: matrix.php-versions == '8.4'
+              run: |
+                export COMPOSER_IGNORE_PLATFORM_REQ=php+
+                export BOX_REQUIREMENT_CHECKER=0
             - name: Check Versions
               run: |
                   php -v
diff --git a/composer.json b/composer.json
index e5895b1..de9ad84 100644
--- a/composer.json
+++ b/composer.json
@@ -4,7 +4,7 @@
     "type": "library",
     "require-dev": {
         "friendsofphp/php-cs-fixer": "^3.13",
-        "phpro/grumphp-shim": "^2.3",
+        "phpro/grumphp-shim": "^2.10",
         "phpspec/phpspec": "^7.2",
         "symfony/validator": "^5.4 || ^6.0 || ^7.0",
         "sebastian/comparator": "^4.0"
@@ -17,7 +17,7 @@
         }
     ],
     "require": {
-        "php": "~8.1.0 || ~8.2.0 || ~8.3.0"
+        "php": "~8.1.0 || ~8.2.0 || ~8.3.0 || ~8.4.0"
     },
     "config": {
         "sort-packages": true,