Using Laravel Pennant for Feature Flags in Laravel 10

Laravel Pennant is a package created by the Laravel team and shipped with Laravel 10, offering a powerful feature‑flag system for your applications.

Feature flags enable you to confidently roll out new features incrementally, conduct A/B tests on interface designs, and support trunk‑based development workflows.

The package is officially maintained, well‑tested, and provides several convenient ways to define flags. You can define a flag directly in AppServiceProvider :

<code>public function boot(): void {
    Feature::define('beta-testers', fn (User $user) => match (true) {
        $user->isBetaTester() => true,
        default => false,
    });
}</code>

Alternatively, you can use a class‑based resolver:

<code>class BetaTesters {
    public function resolve(User $user): mixed {
        return match (true) {
            $user->isBetaTester() => true,
            default => false,
        };
    }
}</code>

In a controller you can conditionally execute code based on a flag using Feature::when :

<code>class PodcastController {
    public function index(Request $request): Response {
        return Feature::when(NewApi::class,
            fn () => $this->resolveNewApiResponse($request),
            fn () => $this->resolveLegacyApiResponse($request)
        );
    }
}</code>

You can also inject dependencies and switch between API versions based on a flag:

<code>class PodcastController {
    public function __construct(private readonly RedirectAction $action) {}
    public function index(Request $request): Response {
        return Feature::when(BetaTester::class,
            fn () => $this->action->handle('v2'),
            fn () => $this->action->handle('v1')
        );
    }
}</code>

A middleware example demonstrates redirecting requests when a flag is active:

<code>class VersionMiddleware {
    public function handle(Request $request, Closure $next): mixed {
        if (Feature::active('beta-tester')) {
            return new RedirectResponse(uri: 'generate the url here');
        }
        return $next($request);
    }
}</code>

These examples illustrate that the possibilities with Laravel Pennant are limited only by imagination, allowing you to enhance your application with clean, flexible feature‑flag logic.