Designing a large-scale application using Laravel requires careful planning and consideration of various factors. Here are some key considerations to take into account:

1. Architecture: Laravel follows the Model-View-Controller (MVC) architectural pattern, which separates the application logic into three distinct layers. It’s important to design the application architecture in a way that allows for scalability, maintainability, and flexibility. A common approach is to use a service-oriented architecture (SOA) or a microservices architecture to divide the application into smaller, more manageable components.
2. Database Design: The database design should be carefully considered to ensure that it can scale as the application grows. It’s important to design the database schema to reduce redundancy and improve performance. Laravel’s Eloquent ORM provides a convenient way to interact with the database and supports various database systems.
3. Caching: Caching can significantly improve the performance of a large-scale application. Laravel provides a caching system that supports various drivers like Redis, Memcached, and APC. It’s important to carefully consider which caching driver to use and how to cache data efficiently.
4. Load Balancing: Load balancing is essential to ensure that the application can handle high traffic loads. It’s important to design the application to work with load balancers and use a tool like Laravel Horizon to manage background jobs.
5. Code Organization: As the application grows, the codebase can become difficult to manage. It’s important to design the application in a way that keeps the code organized and easy to maintain. Laravel provides a robust folder structure that can be used to organize code.
6. Testing: Testing is critical to ensure the quality of the application. Laravel provides a testing framework that makes it easy to write and run tests. It’s important to design the application to be testable and to write automated tests to ensure that the application works as expected.
7. Security: Security is critical for any application. It’s important to design the application to be secure and to follow best practices like input validation, data encryption, and user authentication and authorization.

Overall, designing a large-scale application using Laravel requires careful consideration of various factors. By following best practices and designing the application in a scalable and maintainable way, it’s possible to build a high-performance and reliable application.