Software Architecture

Software architecture establishes the high-level structure of systems, defining components, their relationships, and how they communicate. Good architecture enables scalability, maintainability, and evolution.

TL;DR

• Architecture decisions have long-term consequences
• No single "best" architecture - choose based on requirements
• Balance complexity with team capabilities
• Design for change and evolution

Architectural Styles

Monolithic Architecture

• Single deployable unit
• Simpler to develop and deploy initially
• Can become complex and hard to scale

Microservices

• Independent, loosely-coupled services
• Enables team autonomy and technology diversity
• Adds operational complexity

Serverless Architecture

• Function-as-a-Service (FaaS)
• Event-driven, auto-scaling
• Pay-per-use pricing model

Event-Driven Architecture

• Asynchronous communication via events
• Loose coupling between services
• Event sourcing and CQRS patterns

Design Principles

SOLID Principles

• Single Responsibility
• Open/Closed
• Liskov Substitution
• Interface Segregation
• Dependency Inversion

Domain-Driven Design (DDD)

• Bounded contexts
• Ubiquitous language
• Aggregates and entities
• Strategic and tactical design

Clean Architecture

• Dependency inversion
• Separation of concerns
• Framework independence

Scalability Patterns

• Horizontal vs vertical scaling
• Load balancing
• Caching strategies
• Database sharding
• Read replicas
• CDN usage

Mini Example: boundaries and dependency direction

One simple “architecture smell” is when business logic imports framework code directly. A cleaner shape is: handlers/controllers call use cases, and use cases depend on interfaces.

Related Topics

• Backend Development - Server architecture
• Databases - Data architecture
• DevOps - Infrastructure and deployment