Software architecture is both an art and a science. It requires experience, technical judgment, and a deep understanding of many concepts. There are no magic solutions that fit all scenarios, which is why each architecture must be designed based on the specific requirements of the application, the organization, and the team.
Aspects such as performance, scalability, flexibility, reliability, costs, country email list and the technical capacity of the equipment are key factors in decision-making.
Architectural patterns are the fundamental building blocks of a solution. The key is knowing which ones to apply in each context. Below, I share some of my favorite patterns, explaining where they excel.
1. Bounded contexts
Diagram of bounded contexts in eCommerce
Although not a formal pattern, the concept of bounded context, taken from Domain-Driven Design , is one of the most useful tools for building maintainable code.
A bounded context defines a logical and coherent boundary within which a domain model is consistent. This allows for managing the complexity of large applications by keeping concepts from different domains such as catalog, payments, identity, and so on separate.
Additionally, structuring your code according to these contexts helps enormously if you decide to migrate to a modular or microservices-based architecture.
2.Vertical slice architecture
This approach consists of dividing the application into "vertical slices," grouping all the logic needed for a specific functionality (from the UI to the database). It's a natural extension of the Bounded Context approach and promotes high cohesion across functions.
3. Sidecar pattern
Sidecar pattern diagram
The Sidecar pattern consists of a component that runs alongside the main application on the same machine or container. It's used to add cross-functional functionality such as logging, metrics, authentication, or network policies, without touching the main app's code.
4. Service Mesh
Service Mesh Diagram
A Service Mesh takes the Sidecar pattern to the next level, deploying a proxy alongside each service and managing all communication between them. This allows traffic to be encrypted, authenticated, and monitored in a centralized and consistent manner.
5. Publisher-Subscriber (Pub/Sub)
General Publisher-Subscriber Diagram
This pattern enables decoupled asynchronous communication between applications through the use of a Message Broker. It's ideal for integrating services or running long-running processes in a non-blocking manner.
In this Publisher-Subscriber pattern, delivery mechanisms define how published messages are distributed among consumers (subscribers). The two main mechanisms are:
Competing consumers
In this model, multiple consumers subscribe to the same Topic or Queue, but each message is only delivered to one of them. This is ideal when we want to process heavy or long-running tasks in parallel and scale the system easily.
Each consumer "competes" to retrieve the next available message, which allows for workload distribution. This allows for parallel processing of tasks (e.g., generating PDFs, sending emails), load balancing across multiple workers, and horizontal scalability.