What problem does it solve? Backend systems fail when schemas are designed after routes, mutations lack idempotency, and synchronous work blocks event loops. This Skill enforces architecture-first design so data models, API contracts, and concurrency strategies are proven before implementation begins. ## Core Features & Use Cases - Database Architecture Guidance: Normalization to 3NF, index strategy (B-Tree, GIN), transaction boundaries, and ORM pitfalls like the N+1 problem for Postgres and Prisma. - API Contract Design: REST resource modeling, idempotency keys, cursor-based pagination, JWT/session authentication, and RBAC enforcement. - Concurrency & Async Patterns: Background job queues, optimistic concurrency control, connection pool management, and event-loop starvation prevention. - Use Case: When asked to design a multi-tenant SaaS billing backend, the Skill produces a normalized ERD with indexes, an idempotent REST contract, and an async invoice-generation pipeline before any route handler is written. ## Quick Start Ask the assistant to design the database schema and REST API contract for your new feature using the backend-dev engine.
