What problem does it solve? NestJS codebases frequently suffer from circular dependencies, god services, N+1 queries, missing input validation, and inconsistent error handling. This Skill provides a prioritized rule set of 40 best practices across 10 categories so AI-assisted code generation and review follows proven NestJS patterns instead of producing fragile, hard-to-test code. ## Core Features & Use Cases - Prioritized Rule Catalog: 40 rules organized by impact (CRITICAL architecture and dependency injection first, then error handling, security, performance, testing, database, API design, microservices, and DevOps), each with incorrect and correct TypeScript code examples. - Code Review Guidance: Reference specific rules like arch-avoid-circular-deps, security-validate-all-input, or db-avoid-n-plus-one when reviewing or refactoring NestJS modules, controllers, and services. - Production Patterns: Covers JWT authentication, class-validator input validation, TypeORM transactions and migrations, caching, event-driven decoupling, structured logging, and graceful shutdown. - Use Case: When asked to add a new orders feature, the Skill guides creation of a feature module with constructor injection, DTO validation pipes, transactional saves, and proper module exports instead of a tangled god service. ## Quick Start Review my NestJS users module against the architecture and dependency injection rules and refactor any violations you find.
