diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 74a03c8..ae6d0ae 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -9,8 +9,8 @@ jobs:
       fail-fast: true
       matrix:
         os: [ubuntu-latest]
-        php: [8.2, 8.1]
-        stability: [prefer-stable]
+        php: [8.2, 8.1, 8.0]
+        stability: [prefer-lowest, prefer-stable]
 
     name: P${{ matrix.php }} - ${{ matrix.stability }} - ${{ matrix.os }}
 
diff --git a/composer.json b/composer.json
index 60953d9..b7dc3dd 100644
--- a/composer.json
+++ b/composer.json
@@ -20,9 +20,7 @@
         "symfony/validator": "^6.3"
     },
     "require-dev": {
-        "phpunit/phpunit": "^9.0",
-        "phpmd/phpmd" : "@stable",
-        "friendsofphp/php-cs-fixer": "^2.6"
+        "phpunit/phpunit": "^9.0"
     },
     "autoload": {
         "psr-4": {