diff --git a/.github/workflows/buid_release.yaml b/.github/workflows/buid_release.yaml
index 945a240dac..64502109af 100644
--- a/.github/workflows/buid_release.yaml
+++ b/.github/workflows/buid_release.yaml
@@ -50,7 +50,7 @@ jobs:
             -   run: rm -rf tests ecs-build/packages/coding-standard/tests ecs-build/ecs.php ecs-build/phpstan.neon ecs-build/phpunit.xml ecs-build/.gitignore ecs-build/.editorconfig
 
             # 2. downgrade via Rector
-            -   run: rector-local/vendor/bin/rector process ecs-build/bin ecs-build/config/config.php ecs-build/packages ecs-build/src ecs-build/vendor --config build/config/config-downgrade.php --ansi --no-diffs
+            -   run: rector-local/vendor/bin/rector process ecs-build/bin ecs-build/config/config.php ecs-build/packages ecs-build/src ecs-build/stubs ecs-build/vendor --config build/config/config-downgrade.php --ansi --no-diffs
 
             # 3. prefix classes
             -   run: |
@@ -59,8 +59,8 @@ jobs:
                     # download php-scoper
                     wget https://github.com/humbug/php-scoper/releases/download/0.18.17/php-scoper.phar -N --no-verbose
 
-                    # scope /bin, /config, /packages, /src, /vendor and composer.json
-                    php -d memory_limit=-1 php-scoper.phar add-prefix bin config packages/coding-standard/src src vendor composer.json --output-dir ../ecs-prefixed-downgraded --config scoper.php --force --ansi --working-dir ecs-build
+                    # scope /bin, /config, /packages, /src, /stubs, /vendor and composer.json
+                    php -d memory_limit=-1 php-scoper.phar add-prefix bin config packages/coding-standard/src src stubs vendor composer.json --output-dir ../ecs-prefixed-downgraded --config scoper.php --force --ansi --working-dir ecs-build
 
                     # dump composer autoload
                     composer dump-autoload --working-dir ecs-prefixed-downgraded --ansi --classmap-authoritative --no-dev
diff --git a/.github/workflows/configured_fixer.yaml b/.github/workflows/configured_fixer.yaml
new file mode 100644
index 0000000000..35883dffe7
--- /dev/null
+++ b/.github/workflows/configured_fixer.yaml
@@ -0,0 +1,53 @@
+name: Configured Fixer
+
+# verifies https://github.com/ecsphp/ecs-src/issues/44
+# configuring a PHP-CS-Fixer fixer runs ConfigurableFixerTrait::configure(), which calls
+# PhpCsFixer\Console\Application::getMajorVersion(). That class extends the Symfony console
+# Application, which ECS replaces and does not ship - so the run must not fatal there.
+
+on:
+    pull_request:
+    push:
+        branches:
+            - main
+
+jobs:
+    configured_fixer:
+        runs-on: ubuntu-latest
+
+        steps:
+            -   uses: actions/checkout@v4
+
+            -
+                uses: shivammathur/setup-php@v2
+                with:
+                    php-version: 8.4
+                    coverage: none
+
+            -   run: composer install --no-progress --ansi
+
+            -
+                name: "Create a config with a configured PHP-CS-Fixer fixer"
+                run: |
+                    mkdir -p build/nested
+                    printf '<?php  $%s=1;\n' 'x' > build/nested/some_file.php
+                    cat > build/configured-fixer-ecs.php <<'PHP'
+                    <?php
+                    declare(strict_types=1);
+                    return \Symplify\EasyCodingStandard\Config\ECSConfig::configure()
+                        ->withPaths([__DIR__ . '/nested'])
+                        ->withPreparedSets(psr12: true)
+                        ->withConfiguredRule(
+                            \PhpCsFixer\Fixer\FunctionNotation\NullableTypeDeclarationForDefaultNullValueFixer::class,
+                            ['use_nullable_type_declaration' => false]
+                        );
+                    PHP
+
+            -
+                name: "ecs check must run without a fatal error"
+                run: |
+                    OUTPUT="$(bin/ecs check --config=build/configured-fixer-ecs.php --no-progress-bar --ansi 2>&1 || true)"
+                    echo "$OUTPUT"
+                    echo "$OUTPUT" | grep -q 'some_file.php'
+                    ! echo "$OUTPUT" | grep -q 'Fatal error'
+                    ! echo "$OUTPUT" | grep -q 'Console\\Application" not found'
diff --git a/composer.json b/composer.json
index 5121355024..1ce82ecbca 100644
--- a/composer.json
+++ b/composer.json
@@ -48,7 +48,10 @@
         "psr-4": {
             "Symplify\\EasyCodingStandard\\": "src",
             "Symplify\\CodingStandard\\": "packages/coding-standard/src"
-        }
+        },
+        "classmap": [
+            "stubs"
+        ]
     },
     "autoload-dev": {
         "psr-4": {
diff --git a/stubs/symfony-console-application.php b/stubs/symfony-console-application.php
new file mode 100644
index 0000000000..ffd4b5700c
--- /dev/null
+++ b/stubs/symfony-console-application.php
@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Symfony\Component\Console;
+
+/**
+ * ECS replaces "symfony/console" with its own console, so this class is never installed.
+ * Yet php-cs-fixer's Application extends it, and PHP must resolve the parent class before
+ * PhpCsFixer\Console\Application::getMajorVersion() can be called - which ConfigurableFixerTrait
+ * does for every fixer configured with a deprecated option.
+ *
+ * Only the class declaration is needed, as ECS never runs the php-cs-fixer console.
+ *
+ * @see https://github.com/ecsphp/ecs-src/issues/44
+ */
+class Application
+{
+    public function __construct(string $name = 'UNKNOWN', string $version = 'UNKNOWN')
+    {
+    }
+}