slimphp/Slim · error · RuntimeException

Could not detect any PSR-17 ResponseFactory implementations.

Error message

Could not detect any PSR-17 ResponseFactory implementations. Please install a supported implementation in order to use `AppFactory::create()`. See https://github.com/slimphp/Slim/blob/4.x/README.md for a list of supported implementations.

What it means

Error "Could not detect any PSR-17 ResponseFactory implementations. Please install a supported implementation in order to use `AppFactory::create()`. See https://github.com/slimphp/Slim/blob/4.x/README.md for a list of supported implementations." thrown in slimphp/Slim.

Source

Thrown at Slim/Factory/AppFactory.php:152

        }

        $psr17FactoryProvider = static::$psr17FactoryProvider ?? new Psr17FactoryProvider();

        /** @var Psr17Factory $psr17factory */
        foreach ($psr17FactoryProvider->getFactories() as $psr17factory) {
            if ($psr17factory::isResponseFactoryAvailable()) {
                $responseFactory = $psr17factory::getResponseFactory();

                if (static::$streamFactory || $psr17factory::isStreamFactoryAvailable()) {
                    $streamFactory = static::$streamFactory ?? $psr17factory::getStreamFactory();
                    return static::attemptResponseFactoryDecoration($responseFactory, $streamFactory);
                }

                return $responseFactory;
            }
        }

        throw new RuntimeException(
            "Could not detect any PSR-17 ResponseFactory implementations. " .
            "Please install a supported implementation in order to use `AppFactory::create()`. " .
            "See https://github.com/slimphp/Slim/blob/4.x/README.md for a list of supported implementations."
        );
    }

    protected static function attemptResponseFactoryDecoration(
        ResponseFactoryInterface $responseFactory,
        StreamFactoryInterface $streamFactory
    ): ResponseFactoryInterface {
        if (
            static::$slimHttpDecoratorsAutomaticDetectionEnabled
            && SlimHttpPsr17Factory::isResponseFactoryAvailable()
        ) {
            return SlimHttpPsr17Factory::createDecoratedResponseFactory($responseFactory, $streamFactory);
        }

        return $responseFactory;

View on GitHub (pinned to 80900fb39c)

When it happens

Trigger: Thrown at Slim/Factory/AppFactory.php:152 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of slimphp/Slim@80900fb39c (2026-08-21). Data as JSON: /api/errors/46de682f1a40f763. Report an issue: GitHub.