Software architecture patterns give structure to complex systems. Here are the core ones you’ll hear about most often:

1. Layered (N-Tier)

Probably the most common. Code is split into layers (presentation, business logic, data). Easy to understand and maintain, but can get rigid as systems grow.

2. Client–Server

A clear split between a server that provides services and clients that consume them. Think web apps: browser < >️ backend.

3. Microservices

Instead of one big application, the system is broken into many small, independently deployable services. Offers flexibility and scalability, but adds complexity in communication and monitoring.

4. Event-Driven

Components communicate through events (messages). Decoupled and scalable, but requires strong attention to consistency and debugging.

5. Pipe-and-Filter

Data flows through a sequence of processing steps (filters). Great for stream processing, compilers, or image pipelines.

6. Service-Oriented Architecture (SOA)

An older cousin of microservices. Systems are built from reusable services, often communicating via enterprise buses. Still relevant in big organizations.

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Why patterns matter

Architecture patterns are tried and tested blueprints. They give teams a shared vocabulary and help avoid reinventing the wheel. Most real-world systems combine multiple patterns (for example, a layered microservice that’s event-driven inside).

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References:

• Bass, L., Clements, P., & Kazman, R. (2012). Software Architecture in Practice (3rd ed.). Addison-Wesley.
• Nuseibeh, B. (2001). Weaving Together Requirements and Architectures. IEEE Computer, 34(3), 115-117.