How can a Laravel developer implement or use Custom middleware correctly? Explain the flow, key steps, and practical considerations.

How can a Laravel developer implement or use Custom middleware correctly? Explain the flow, key steps, and practical considerations. A practical implementation starts by deciding which application layer owns the responsibility, then using Laravel's framework API consistently, validating input where necessary, authorizing state-changing actions, and testing both successful and failure paths. Applications can create custom middleware for business or security rules that belong at the request boundary. Example pattern: public function handle($request, Closure $next) { if (! $request->user()) { return redirect('/login'); } return $next($request); } The code is intentionally small; a production implementation should also consider validation, authorization, error handling, logging, monitoring, and test coverage relevant to the feature.