architecture

name	architecture
description	Software architecture patterns, system design, and scalability principles.
globs	["**/README.md","**/ARCHITECTURE.md","**/docs/**"]
priority	70
tags	["architecture"]

Software Architecture

Design Principles

• SOLID principles
• Separation of concerns
• Dependency inversion
• Composition over inheritance
• Program to interfaces, not implementations
• YAGNI — don't build what you don't need

Common Patterns

• MVC / MVVM / MVP for UI layers
• Repository pattern for data access
• Service layer for business logic
• Factory pattern for object creation
• Observer/Event pattern for decoupling
• Strategy pattern for algorithm selection
• Middleware pattern for cross-cutting concerns

API Design

• Use REST for CRUD, GraphQL for flexible queries
• Version your APIs (URL or header)
• Use pagination for lists
• Use proper HTTP status codes
• Implement rate limiting
• Document with OpenAPI/Swagger

Scalability

• Horizontal scaling over vertical
• Use caching (Redis, CDN)
• Use message queues for async work
• Database read replicas
• Sharding for write-heavy workloads
• Use CDN for static assets

System Design

• Start simple, scale when needed
• Use load balancers for distribution
• Design for failure (retries, circuit breakers)
• Use health checks and monitoring
• Implement graceful shutdown