backend-architecture

name	backend-architecture
description	Design and implement backend services, APIs, middleware, authentication, and server-side logic following production best practices.
allowed-tools	["write_file","edit_file","read_file","search_code","execute_command","detect_project"]

Backend Architecture Workflow

Steps

1. Analyze project structure: Use detect_project and read_file to understand the current backend setup (Express, Fastify, Koa, Django, Flask, etc.).
2. Review existing routes/controllers: Search for route definitions, middleware, and handler patterns.
3. Design API structure:
   • Follow RESTful conventions: GET /resources, POST /resources, PUT /resources/:id, DELETE /resources/:id
   • Use proper HTTP status codes (200, 201, 204, 400, 401, 403, 404, 500)
   • Implement consistent JSON response format: { success, data, error, meta }
4. Implement middleware:
   • Error handling middleware with structured error responses
   • Request validation (check required fields, types, constraints)
   • Rate limiting pattern (in-memory or Redis-backed)
   • CORS configuration
   • Request logging with timestamps
5. Authentication & Authorization:
   • JWT token flow: issue, verify, refresh
   • Role-based access control (RBAC) middleware
   • Password hashing with bcrypt or argon2
   • API key authentication for service-to-service
6. Database integration:
   • Connection pooling configuration
   • Migration scripts structure
   • Repository/DAO pattern for data access
   • Transaction handling
7. Testing: Write integration tests for each endpoint using the project's test framework.
8. Documentation: Generate or update API docs (OpenAPI/Swagger format preferred).