CtrlK
BlogDocsLog inGet started
Tessl Logo

create-a-backend

Backend architecture guidance. Use when planning, building, or migrating an API or backend; choosing between Functions, Services, containers, Workflow, Queues, and Marketplace databases; or selecting a supported backend framework or runtime.

SKILL.md
Quality
Evals
Security

Create a Backend

Help the user create a backend by choosing an architecture before reaching for implementation details. Start from the workload, not the programming language. Vercel runs complex backend applications, not just frontends.

Product map

NeedVercel product
HTTP APIs, webhooks, streaming, or framework server codeVercel Functions with Fluid compute
Bidirectional realtime connections (WebSockets)Vercel Functions with Fluid compute; no separate realtime service required
A frontend and one or more backends (API endpoints) that deploy togetherVercel Services
An existing Dockerfile, custom runtime, or system dependenciesContainer images on Vercel Functions, optionally composed with Services
Durable multi-step work with retries, sleeps, or external eventsVercel Workflows
Background jobs, buffering, fan-out, or direct message routingVercel Queues
Scheduled HTTP workVercel Cron Jobs; use Workflow when the job itself must be durable
Postgres, Redis, NoSQL, vector, or other application dataStorage integrations from the Vercel Marketplace
Files and user uploadsVercel Blob
Global, read-heavy configurationGlobal Config

Use Functions for the normal request/response backend. Use Services when independently built components should share one deployment, routing layer, preview URL, and rollback. Use separate Vercel projects when components need independent release cycles.

Prefer a native Functions runtime for supported frameworks. Use container images when the application already has a Dockerfile or requires a custom runtime or system dependencies. They run as autoscaling, stateless Functions rather than always-on container hosts.

Choose Queues for background jobs, buffering, fan-out, and message routing. Choose Workflow for durable multi-step business logic.

Databases and data stores

Provision data stores through the Marketplace so credentials are injected into the project and environments stay connected. Check the current catalog before choosing a provider.

  • Postgres: Neon, Supabase, AWS/Aurora, Nile, Prisma
  • MySQL: AWS/Aurora
  • Redis and key-value: Upstash, Redis
  • Document and NoSQL: MongoDB Atlas, AWS
  • SQLite: Turso
  • Realtime application backend: Convex
  • Analytics: MotherDuck

Keep the database close to the Functions region and use a serverless-compatible connection or pool.

Backend frameworks

Vercel provides first-class backend examples and integrations for these frameworks:

  • Node.js and TypeScript: Elysia, Express, Fastify, H3, Hono, Koa, NestJS, Nitro, and xmcp. Next.js Route Handlers are the natural choice when the backend belongs to a Next.js application.
  • Python: FastAPI, Flask, and Django. Other WSGI or ASGI applications can run when they export a compatible app, with additional configuration as needed.
  • Go: supported as a Vercel Functions runtime.

Frontend and backend combinations, for example a Next.js/Vite/SvelteKit frontend with a FastAPI/Flask/Express/Go backend, can be deployed together in one project using Services.

Prefer the user's existing framework. For a new project, choose based on ecosystem and application needs.

Work sequence

  1. Identify synchronous requests, asynchronous work, persistent data, and independently deployed components.
  2. Select the products from the map, then select the framework.
  3. Load the focused skill for implementation: vercel-functions, vercel-services, workflow, vercel-storage, or marketplace.
  4. Confirm function limits, regions, environment variables, observability, and current product availability in the official docs before deployment.
Repository
vercel/vercel-plugin
Last updated
First committed

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.