diff --git a/.github/workflows/php.yml b/.github/workflows/php.yml
index 4006475..0d0b19c 100644
--- a/.github/workflows/php.yml
+++ b/.github/workflows/php.yml
@@ -8,26 +8,28 @@ on:
 
 jobs:
   build:
-
     runs-on: ubuntu-latest
 
     strategy:
       matrix:
-        php: [8.1, 8.2]
+        php: [8.0, 8.1, 8.2, 8.3, 8.4, 8.5]
 
     steps:
-    - uses: actions/checkout@v2
+      - name: Checkout code
+        uses: actions/checkout@v4
 
-    - name: Set PHP version
-      uses: shivammathur/setup-php@v2
-      with:
-        php-version: ${{ matrix.php }}
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          coverage: none
+          tools: composer
 
-    - name: Install dependencies
-      run: composer update --prefer-dist --no-progress --no-suggest
+      - name: Install dependencies
+        run: composer update --prefer-dist --no-progress --no-interaction
 
-    - name: Execute PHPUnit
-      run: vendor/bin/phpunit
+      - name: Run PHPUnit
+        run: vendor/bin/phpunit
 
-    - name: Execute PHPStan analyse
-      run: vendor/bin/phpstan
\ No newline at end of file
+      - name: Run PHPStan
+        run: vendor/bin/phpstan analyse
diff --git a/composer.json b/composer.json
index bd76d89..537f660 100644
--- a/composer.json
+++ b/composer.json
@@ -16,11 +16,11 @@
     }
   ],
   "require": {
-    "php": "^8.1"
+    "php": "^8.0"
   },
   "require-dev": {
     "phpunit/phpunit": "^9.0",
-    "symfony/var-dumper": "^6.3",
+    "symfony/var-dumper": "^5.4",
     "phpstan/phpstan": "^1.10"
   },
   "autoload": {
diff --git a/src/Manager.php b/src/Manager.php
index 9e091ba..a88a23d 100644
--- a/src/Manager.php
+++ b/src/Manager.php
@@ -6,10 +6,15 @@
 
 abstract class Manager
 {
+    protected Aggregator $aggregator;
+
     public function __construct(
         protected bool $singleton = false,
-        protected Aggregator $aggregator = new Aggregator(),
-    ) {}
+        ?Aggregator $aggregator = null,
+    ) {
+        // php8.0 retro-compatibility
+        $this->aggregator = $aggregator ?? new Aggregator();
+    }
 
     /**
      * Get the default driver name.
@@ -30,7 +35,7 @@ public function __call(string $method, array $parameters): mixed
      * @throws \DeGraciaMathieu\Manager\Exceptions\DriverOverwrittenException
      * @throws \DeGraciaMathieu\Manager\Exceptions\DriverResolutionException
      */
-    public function driver(string $name = null): mixed
+    public function driver(?string $name = null): mixed
     {
         $name = $name ?: $this->getDefaultDriver();