AgentSkillsCN

backend

专注于API、数据库、服务器端模式、数据建模、可扩展性与集成方案的后端工程专家。无论是API设计、数据库相关问题，还是后端特有的技术难题，皆可寻求其专业指导。

SKILL.md
--- frontmatter
name: backend
description: |
  Backend engineering specialist for APIs, databases, server-side patterns,
  data modeling, scalability, and integrations. Use for API design, database
  questions, or backend-specific concerns.

Backend Skill

Specialized backend engineering guidance for APIs, databases, and server-side systems.

When to Use

  • •Designing APIs (REST, GraphQL)
  • •Database schema or query questions
  • •Server-side architecture
  • •Data modeling
  • •Authentication and authorization
  • •Scalability and performance
  • •User says "backend", "API", "database", "server"

Key Focus Areas

API Design

  • •RESTful conventions (resources, methods, status codes)
  • •GraphQL schema design
  • •API versioning strategies
  • •Request/response validation
  • •Error handling and messaging
  • •Pagination and filtering
  • •Rate limiting

Database Patterns

  • •Schema design and normalization
  • •Indexing strategies
  • •Query optimization
  • •Transaction management
  • •Connection pooling
  • •Migration best practices
  • •N+1 query prevention

Data Modeling

  • •Entity definition
  • •Relationship modeling (1:1, 1:N, N:M)
  • •Data types and constraints
  • •Validation rules
  • •Audit trails

Authentication & Authorization

  • •Password hashing (bcrypt, argon2)
  • •JWT or session management
  • •OAuth2 / OIDC patterns
  • •RBAC (Role-Based Access Control)
  • •API key management

Performance & Scalability

  • •Query optimization and EXPLAIN plans
  • •Caching strategies (Redis, memcached)
  • •Background jobs (Celery, Bull)
  • •Database read replicas
  • •Horizontal scaling

Integration Patterns

  • •External API resilience (retry, timeout, circuit breaker)
  • •Webhook handling with retry
  • •Message queue patterns
  • •Idempotency for critical operations

Review Process

Use comprehensive checklists for:

  • •API quality (REST conventions, validation, versioning)
  • •Database quality (schema, indexes, transactions)
  • •Security (auth, validation, injection prevention)

See refs/checklists.md for detailed checklists, anti-patterns, and output templates.

Code Patterns

Common backend patterns for:

  • •API endpoints with auth and validation
  • •Query optimization and N+1 prevention
  • •Authentication and authorization
  • •External API integration with resilience
  • •Caching strategies

See refs/patterns.md for code examples and best practices.

Notes

  • •Always hash passwords (never plaintext)
  • •Validate all input at API boundaries
  • •Use transactions for multi-step operations
  • •Index foreign keys and query fields
  • •Use background jobs for slow operations