Explain advanced event-driven architecture (EDA) design patterns in large-scale PHP systems.

Event-driven architecture decouples services using asynchronous events, enabling scalable, loosely coupled, and highly resilient PHP systems.

Event-driven architecture (EDA) replaces synchronous request-response coupling with asynchronous communication through events. Instead of services calling each other directly, they emit events that other services subscribe to.

Core building blocks:

Systems that publish events (e.g., OrderCreated, PaymentProcessed).

Kafka, RabbitMQ, Redis Streams.

Independent services reacting to events.

Core design patterns:

Only signals that something happened.

2.…