backendlisted

# Backend > First, apply all rules from the **nodejs-backend-patterns** skill. The rules below extend and override that baseline for Singleton SD personal projects. > > When the backend is paired with a Next.js frontend, also apply **next-best-practices** for route handler and BFF patterns on the frontend side. --- ## Stack Decision | Scenario | Choice | |---|---| | Complex domain, multiple consumers, long-lived API | **NestJS** | | Simple CRUD, single Next.js frontend, fast iteration | **Next.js Route Handlers** as BFF | | Need background jobs, queues, or WebSockets | **NestJS** | Default to **NestJS** for any project that will outlive a prototype. --- ## Canonical Stack | Concern | Choice | Why | |---|---|---| | Framework | NestJS | Opinionated structure, DI, decorators | | Language | TypeScript strict | Always | | Database | SQL Server | Primary relational store; strong tooling, T-SQL, enterprise-ready | | ORM | Prisma | Type-safe, great DX, auto-generated client | | Validation | class-validator + class-transformer | Native NestJS ValidationPipe integration | | Auth | @nestjs/jwt + @nestjs/passport | Standard NestJS auth ecosystem | | Config | @nestjs/config | Typed env vars with Joi schema validation | | Logging | Pino via nestjs-pino | Structured JSON logs | --- ## Project Setup ```bash npm i -g @nestjs/cli nest new my-api --strict cd my-api # Core deps npm install @nestjs/config @nestjs/jwt @nestjs/passport passport passport-jwt npm install class-validator c