backend-design

name	backend-design
description	Design robust backend systems and APIs. Use when users ask to plan or implement services, data models, or integrations.

Backend Design Skill

This skill guides the design of reliable backend systems, APIs, and data models with clear trade-offs, strong correctness guarantees, and operational readiness.

Design Thinking

• Scope: Identify core use cases, data flows, and integration points.
• Constraints: Latency, throughput, availability, compliance, and deployment limits.
• Data: Define entities, relationships, invariants, and lifecycle.
• Reliability: Error handling, retries, idempotency, and consistency model.

Architecture Guidelines

• API Design: Explicit contracts, versioning, validation, and error shape.
• Storage: Choose stores based on access patterns and durability needs.
• Performance: Indexing, caching, batching, and async processing.
• Security: AuthN/AuthZ, least privilege, secrets handling, auditability.
• Observability: Logging, metrics, tracing, and alerting signals.
• Scalability: Stateless services where possible, clear scaling boundaries.

Output Requirements

Provide a clear backend plan or implementation that includes:

• Data model and key invariants
• API endpoints or service interfaces
• Failure modes and recovery strategy
• Performance and scaling considerations
• Security and observability notes

Response Checklist

Backend Design Checklist

- [ ] Confirm requirements and constraints
- [ ] Define data model and invariants
- [ ] Specify API contracts and error shape
- [ ] Address failure modes and consistency
- [ ] Cover performance, scaling, and caching
- [ ] Include security and observability plans