diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index a5bc5da..d2d7040 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -55,19 +55,35 @@ jobs:
           # LTS version of Symfony
           -   php-version: '8.1'
               symfony-version: '6.4.*'
+          # Explicit Symfony versions
+          -  php-version: '8.1'
+             symfony-version: '6.4'
+          -  php-version: '8.2'
+             symfony-version: '7.0'
+          -  php-version: '8.4'
+             symfony-version: '8.0.x-dev' # TODO: change to '8.0' when Symfony 8.0 is released
+             minimum-stability: 'dev' # TODO: remove when Symfony 8.0 is released
+
     steps:
       - uses: actions/checkout@v4
 
       - name: Install PHP
         uses: shivammathur/setup-php@v2
         with:
-          php-version: 8.2
+          php-version: ${{ matrix.php-version }}
           tools: symfony-cli, flex
 
+      - name: Allow Flex Plugin
+        run: composer global config --no-plugins allow-plugins.symfony/flex true
+        
+      - name: Configure Composer stability
+        run: composer config minimum-stability ${{ matrix.minimum-stability }}
+
       - name: Install Composer dependencies
         run: |
-          symfony composer config minimum-stability ${{ matrix.minimum-stability }}
-          SYMFONY_REQUIRE=${{ matrix.symfony-version || '>=6.4' }} symfony composer update ${{ matrix.dependency-version == 'lowest' && '--prefer-lowest' || '' }}
+          composer update ${{ matrix.dependency-version == 'lowest' && '--prefer-lowest' || '' }}
+        env:
+          SYMFONY_REQUIRE: ${{ matrix.symfony-version || '>=5.4' }}
 
       - name: Create a new Symfony project
         run: |
diff --git a/composer.json b/composer.json
index 2546425..95ef357 100644
--- a/composer.json
+++ b/composer.json
@@ -15,16 +15,17 @@
             "email": "hugo@alliau.me"
         }
     ],
+    "minimum-stability": "dev",
     "require": {
         "php": ">=8.1",
-        "symfony/console": "^6.4|^7.0",
-        "symfony/filesystem": "^6.4|^7.0",
-        "symfony/http-client": "^6.4|^7.0",
-        "symfony/process": "^6.4|^7.0"
+        "symfony/console": "^6.4|^7.0|^8.0",
+        "symfony/filesystem": "^6.4|^7.0|^8.0",
+        "symfony/http-client": "^6.4|^7.0|^8.0",
+        "symfony/process": "^6.4|^7.0|^8.0"
     },
     "require-dev": {
-        "phpstan/phpstan": "^1.11",
-        "symplify/easy-coding-standard": "^12.1.2",
-        "symfony/framework-bundle": "^6.4|^7.0"
+        "phpstan/phpstan": "^2.1.21",
+        "symplify/easy-coding-standard": "12.5.22",
+        "symfony/framework-bundle": "^6.4|^7.0|^8.0"
     }
 }
diff --git a/src/BiomeJsBinary.php b/src/BiomeJsBinary.php
index e83e281..9e40e94 100644
--- a/src/BiomeJsBinary.php
+++ b/src/BiomeJsBinary.php
@@ -42,7 +42,7 @@ private static function isMusl(): bool
     {
         static $isMusl = null;
 
-        if (null !== $isMusl) {
+        if (is_bool($isMusl)) {
             return $isMusl;
         }
 
diff --git a/src/KocalBiomeJsBundle.php b/src/KocalBiomeJsBundle.php
index c67e115..10c2fcd 100644
--- a/src/KocalBiomeJsBundle.php
+++ b/src/KocalBiomeJsBundle.php
@@ -10,7 +10,7 @@
 
 final class KocalBiomeJsBundle extends Bundle
 {
-    protected function createContainerExtension(): ?ExtensionInterface
+    protected function createContainerExtension(): ExtensionInterface
     {
         return new BiomeJsExtension();
     }