--- title: Backends description: Backends on Vercel run on Fluid compute with Active CPU pricing, plus Instant Rollback, the Vercel Firewall, protected previews, and rolling releases. url: "https://vercel.com/kb/backends" published: 2025-11-03 last_updated: 2026-10-15 install_vercel_plugin: npx plugins add vercel/vercel-plugin --- # Backends Backends on Vercel run on Fluid compute with Active CPU pricing, plus Instant Rollback, the Vercel Firewall, protected previews, and rolling releases. ## Build with a Backend Template on Vercel - [Build with a Nitro starter template](/kb/guide/build-with-a-nitro-starter-template): Deploy a Nitro app to Vercel from a starter template. Compare the Nitro Starter, route rules, cached HTTP handler, plugins, Slack Bolt, and iMessage AI agent templates, then ship to a live URL. - [Build with a Hono starter template](/kb/guide/build-with-a-hono-starter-template): Deploy a Hono app to Vercel from a starter template. Compare the Hono API starter, MCP server, AI SDK, Slack Bolt, Next.js, Turborepo, and domco templates, then ship to a live URL. - [Build with an Express starter template](/kb/guide/build-with-a-express-starter-template): Deploy an Express app to Vercel from a template. Browse Express starters from Vercel and the community, then run them locally with the Vercel CLI. - [Build with a FastAPI starter template](/kb/guide/build-with-a-fastapi-starter-template): Browse FastAPI starter templates for Vercel and deploy one in a few steps. Compare minimal, AI, agent, and full-stack FastAPI templates on the Python runtime. - [Build with a Flask starter template](/kb/guide/build-with-a-flask-starter-template): Deploy a Flask app to Vercel from a starter template. Compare the Flask Hello World starter, AI SDK, alt text generator, and Next.js templates, then ship to a live URL. ## Migrate a Python API to Vercel - [Migrate a Python API from Heroku to Vercel](/kb/guide/migrate-a-python-api-from-heroku-to-vercel): Move a FastAPI, Flask, or Django API from Heroku to Vercel Functions. Replace your Procfile, worker dynos, Heroku Scheduler jobs, and Heroku Postgres. - [Migrate a Python API from Render to Vercel](/kb/guide/migrate-a-python-api-from-render-to-vercel): Move a FastAPI, Flask, or Django API from Render to Vercel Functions. Translate render.yaml and replace persistent disks, background workers, and cron jobs. - [Migrate a Python API from Railway to Vercel](/kb/guide/migrate-a-python-api-from-railway-to-vercel): Move a FastAPI, Flask, or Django API from Railway to Vercel Functions. Replace railway.json start commands, volumes, Celery workers, and cron services. ## Zero-Configuration Backends on Vercel - [Using xmcp with Next.js](/kb/guide/using-xmcp-with-nextjs): Add an MCP server to an existing Next.js app with xmcp. Create typed tools, add authentication, and deploy to Vercel as a Vercel Function. - [How to ship an H3 app on Vercel](/kb/guide/ship-a-h3-app-on-vercel): Deploy an H3 app to Vercel with zero configuration. Learn to configure streaming, middleware, cron jobs, the Bun runtime, and observability. - [How to ship a Fastify app on Vercel](/kb/guide/ship-a-fastify-app-on-vercel): Deploy a Fastify app to Vercel with zero configuration, then add streaming, lifecycle hooks, cron jobs, and observability. - [How to ship an Express app on Vercel](/kb/guide/ship-a-express-app-on-vercel): Deploy an Express app to Vercel with zero configuration. Configure response streaming, middleware, cron jobs, the Bun runtime, and observability. - [How to ship a FastAPI app on Vercel](/kb/guide/ship-a-fastapi-app-on-vercel): Deploy a FastAPI app to Vercel with zero configuration. Learn how the Python runtime, Vercel Functions, streaming, middleware, and cron jobs work together. - [How to ship a Koa app on Vercel](/kb/guide/ship-a-koa-app-on-vercel): Deploy a Koa app to Vercel with zero configuration. Learn how to ship from the Vercel CLI or Git, and configure response streaming, middleware, cron jobs, and Observability. - [How to ship a NestJS app on Vercel](/kb/guide/ship-a-nestjs-app-on-vercel): Deploy a NestJS app to Vercel with zero configuration. Learn how to ship from a template, the Nest CLI, or Git, and configure response streaming, middleware, cron jobs, and Observability. - [How to ship a Flask app on Vercel](/kb/guide/ship-a-flask-app-on-vercel): Deploy a Flask app to Vercel with zero configuration. Learn how to ship from a template, the Vercel CLI, or Git, and configure response streaming, middleware, cron jobs, the Bun runtime, and Observability. - [How to ship an Elysia app on Vercel](/kb/guide/ship-a-elysia-app-on-vercel): Deploy a Elysia app to Vercel with zero configuration. Learn how to ship from a template, the Vercel CLI, or Git, and configure response streaming, middleware, cron jobs, the Bun runtime, and Observability. - [How to ship a Nitro app on Vercel](/kb/guide/ship-a-nitro-app-on-vercel): Deploy a Nitro app to Vercel with zero configuration. Learn how to ship from a template, the Vercel CLI, or Git, and configure ISR, cron jobs, Vercel Queues, per-route function settings, and Observability. - [How to ship a Hono app on Vercel](/kb/guide/ship-a-hono-app-on-vercel): Deploy a Hono app to Vercel with zero configuration. Learn how to ship from a template, the Vercel CLI, or Git, and configure response streaming, middleware, cron jobs, the Bun runtime, and Observability. ## Learn more about Python - [7 practical use cases for a Python backend in a Next.js app](https://vercel.com/i/python-backend-nextjs-use-cases): See when a Python backend adds value to a Next.js app, with examples for AI, data analysis, document processing, predictions, and existing applications. - [How to connect a Python AI agent to a Next.js app](https://vercel.com/i/python-ai-agent-nextjs): Connect a Python AI agent to Next.js with FastAPI and AI SDK UI. Stream responses, display Python tool results, and configure a shared deployment. - [Where should you host a Python API?](https://vercel.com/i/where-to-host-python-api): Choose Python API hosting by framework support, dependencies, execution limits, storage, and where your frontend and database run. ## All Backends guides - [Migrate a Python API from Railway to Vercel](/kb/guide/migrate-a-python-api-from-railway-to-vercel): Move a FastAPI, Flask, or Django API from Railway to Vercel Functions. Replace railway.json start commands, volumes, Celery workers, and cron services. - [Migrate a Python API from Render to Vercel](/kb/guide/migrate-a-python-api-from-render-to-vercel): Move a FastAPI, Flask, or Django API from Render to Vercel Functions. Translate render.yaml and replace persistent disks, background workers, and cron jobs. - [Migrate a Python API from Heroku to Vercel](/kb/guide/migrate-a-python-api-from-heroku-to-vercel): Move a FastAPI, Flask, or Django API from Heroku to Vercel Functions. Replace your Procfile, worker dynos, Heroku Scheduler jobs, and Heroku Postgres. - [Use Vercel Passport with Node.js and Python backends](/kb/guide/vercel-passport-backend-frameworks): Read and verify a visitor's Vercel Passport identity in your backend, with examples for Express, Hono, Nitro, and FastAPI. - [Does Vercel support Docker deployments?](/kb/guide/does-vercel-support-docker-deployments): Vercel supports deploying OCI-compatible container images through Vercel Functions and Vercel Container Registry, with Active CPU pricing and automatic scaling. - [Running Docker on Vercel vs Render](/kb/guide/docker-on-vercel-vs-render): Compare how Vercel and Render run Docker workloads, including deployment model, scaling, image sources, state, and networking. - [How to use Vercel Container Registry](/kb/guide/how-to-use-vercel-container-registry): Push, store, and pull OCI container images with Vercel Container Registry, then deploy them to Vercel Functions and Vercel Sandbox. - [Running Docker on Vercel](/kb/guide/docker): Learn how to run Docker on Vercel by deploying OCI container images as Vercel Functions, storing them in Vercel Container Registry (VCR), and running containers in Vercel Sandbox. - [Build Figma-style multiplayer cursors with WebSockets on Vercel](/kb/guide/real-time-board-nextjs-fastapi): Learn how to build Figma-style multiplayer cursors with Next.js and FastAPI, kept consistent across multiple Vercel Function instances using WebSockets and Redis. - [Choosing how to structure your application on Vercel](/kb/guide/structure-your-application): Compare three ways to structure an application on Vercel (a single framework, one project with Services, or separate projects in a monorepo) and learn how to choose based on domains, deploy coupling, and languages. - [How Vercel Services run on Fluid compute](/kb/guide/vercel-services-fluid-compute): The backends in a Vercel Services project run as Vercel Functions on Fluid compute by default. Learn how optimized concurrency, Active CPU pricing, and per-service memory and maxDuration settings make multi-backend projects efficient. - [The Complete Guide to Vercel Services](/kb/guide/vercel-services): Vercel Services let you deploy multiple frontends and backends in one project on a shared domain. Learn how to define services in vercel.json, route requests by path prefix, and connect services with generated environment variables. - [Build a real-time chat app with WebSockets on Vercel](/kb/guide/real-time-chat-websockets): Build and deploy a single-room messaging app in Next.js with real-time chat, typing indicators, and live online user counts using WebSockets and Redis. - [Build with an Express starter template](/kb/guide/build-with-a-express-starter-template): Deploy an Express app to Vercel from a template. Browse Express starters from Vercel and the community, then run them locally with the Vercel CLI. - [Build with a FastAPI starter template](/kb/guide/build-with-a-fastapi-starter-template): Browse FastAPI starter templates for Vercel and deploy one in a few steps. Compare minimal, AI, agent, and full-stack FastAPI templates on the Python runtime. - [How to ship a FastAPI app on Vercel](/kb/guide/ship-a-fastapi-app-on-vercel): Deploy a FastAPI app to Vercel with zero configuration. Learn how the Python runtime, Vercel Functions, streaming, middleware, and cron jobs work together. - [How to ship a Fastify app on Vercel](/kb/guide/ship-a-fastify-app-on-vercel): Deploy a Fastify app to Vercel with zero configuration, then add streaming, lifecycle hooks, cron jobs, and observability. - [How to ship an Express app on Vercel](/kb/guide/ship-a-express-app-on-vercel): Deploy an Express app to Vercel with zero configuration. Configure response streaming, middleware, cron jobs, the Bun runtime, and observability. - [How to ship an H3 app on Vercel](/kb/guide/ship-a-h3-app-on-vercel): Deploy an H3 app to Vercel with zero configuration. Learn to configure streaming, middleware, cron jobs, the Bun runtime, and observability. - [How to ship a NestJS app on Vercel](/kb/guide/ship-a-nestjs-app-on-vercel): Deploy a NestJS app to Vercel with zero configuration. Learn how to ship from a template, the Nest CLI, or Git, and configure response streaming, middleware, cron jobs, and Observability. - [How to ship a Koa app on Vercel](/kb/guide/ship-a-koa-app-on-vercel): Deploy a Koa app to Vercel with zero configuration. Learn how to ship from the Vercel CLI or Git, and configure response streaming, middleware, cron jobs, and Observability. - [Using xmcp with Next.js](/kb/guide/using-xmcp-with-nextjs): Add an MCP server to an existing Next.js app with xmcp. Create typed tools, add authentication, and deploy to Vercel as a Vercel Function. - [Build with a Flask starter template](/kb/guide/build-with-a-flask-starter-template): Deploy a Flask app to Vercel from a starter template. Compare the Flask Hello World starter, AI SDK, alt text generator, and Next.js templates, then ship to a live URL. - [How to ship an Elysia app on Vercel](/kb/guide/ship-a-elysia-app-on-vercel): Deploy a Elysia app to Vercel with zero configuration. Learn how to ship from a template, the Vercel CLI, or Git, and configure response streaming, middleware, cron jobs, the Bun runtime, and Observability. - [How to ship a Flask app on Vercel](/kb/guide/ship-a-flask-app-on-vercel): Deploy a Flask app to Vercel with zero configuration. Learn how to ship from a template, the Vercel CLI, or Git, and configure response streaming, middleware, cron jobs, the Bun runtime, and Observability. - [How to ship a Hono app on Vercel](/kb/guide/ship-a-hono-app-on-vercel): Deploy a Hono app to Vercel with zero configuration. Learn how to ship from a template, the Vercel CLI, or Git, and configure response streaming, middleware, cron jobs, the Bun runtime, and Observability. - [How to ship a Nitro app on Vercel](/kb/guide/ship-a-nitro-app-on-vercel): Deploy a Nitro app to Vercel with zero configuration. Learn how to ship from a template, the Vercel CLI, or Git, and configure ISR, cron jobs, Vercel Queues, per-route function settings, and Observability. - [Build with a Nitro starter template](/kb/guide/build-with-a-nitro-starter-template): Deploy a Nitro app to Vercel from a starter template. Compare the Nitro Starter, route rules, cached HTTP handler, plugins, Slack Bolt, and iMessage AI agent templates, then ship to a live URL. - [Build with a Hono starter template](/kb/guide/build-with-a-hono-starter-template): Deploy a Hono app to Vercel from a starter template. Compare the Hono API starter, MCP server, AI SDK, Slack Bolt, Next.js, Turborepo, and domco templates, then ship to a live URL. - [What is the Nitro Vite plugin?](/kb/guide/nitro-vite-plugin): The Nitro Vite plugin (nitro/vite) adds SSR, API routes, and deploy-anywhere server builds to any Vite app. Learn what it does and how it runs on Vercel. - [Build a fullstack app with Next.js 16 and Prisma Postgres](/kb/guide/nextjs-prisma-postgres): Create a fullstack blog with the Next.js App Router, Prisma, Sign in with Vercel, Prisma Postgres from the Vercel Marketplace, and deploy it to Vercel. - [How to create a contentful asset on Vercel](/kb/guide/how-to-create-a-contentful-asset-on-vercel): This is my wonderful - [How to gradually roll out new versions of your backend](/kb/guide/how-to-gradually-roll-out-new-versions-of-your-backend): Incrementally release updates to your backend to minimize impact of mistakes. - [Efficiently manage database connection pools with Fluid compute](/kb/guide/efficiently-manage-database-connection-pools-with-fluid-compute): How to create high-performance database connection pools without leaking connections - [Using Vercel Sandbox to run Claude’s Agent SDK](/kb/guide/using-vercel-sandbox-claude-agent-sdk): Learn how to deploy Claude's Agent SDK in Vercel Sandbox for secure and isolated execution of AI-powered code generation and autonomous agent tasks. - [Build an MCP Server with Weather tools using Express and Vercel](/kb/guide/mcp-server-with-weather-tool-express): Make your Express weather API accessible to AI assistants through the Model Context Protocol. - [Build an AI Chat Agent with Weather API Tool Calling](/kb/guide/build-ai-agent-weather-api): Build an intelligent conversational agent that fetches real-time weather data using the AI SDK, tool calling, and a backend weather API powered by Express, FastAPI or Nitro - [How to Build a Weather API with Express and Vercel](/kb/guide/weather-api-with-express): Provide real-time weather data to apps and websites with a single Express route. - [How to Build a Weather API with Nitro and Vercel](/kb/guide/weather-api-with-nitro): Provide real-time weather data to apps and websites with a single Nitro route, Vercel cache storage, and Observability. - [Build a Weather API on Vercel: Express, FastAPI, and Nitro](/kb/guide/weather-api-with-fastapi): Build a weather API on Vercel with FastAPI, Express, or Nitro. Compare the three runtimes, add caching and Observability, then deploy the route. - [How to enable CORS on Vercel](/kb/guide/how-to-enable-cors): Learn how to enable CORS on Vercel with vercel.json, Routing Middleware, framework config, and route handlers, plus how to fix preflight blocked by Deployment Protection. - [Hosting your API on Vercel](/kb/guide/hosting-backend-apis): Learn how to build and scale performant APIs on Vercel. - [Troubleshooting Vercel Cron Jobs](/kb/guide/troubleshooting-vercel-cron-jobs): Learn how to troubleshoot cron jobs that aren't being run or logged when using Vercel Cron Jobs. - [How can I use geolocation IP headers?](/kb/guide/geo-ip-headers-geolocation-vercel-functions): Learn how to read geolocation headers on Vercel with Next.js or any frontend framework. - [How can I use Python and JavaScript in the same application?](/kb/guide/how-to-use-python-and-javascript-in-the-same-application): Unlock the power of Python and JavaScript in your apps. Learn to integrate Flask and Next.js for dynamic frontends with AI-capable backends. Perfect for developers keen on hybrid programming. ## Explore other topics in the Vercel Knowledge Base - [Python](/kb/python): Build, deploy, and scale Python on Vercel. Run FastAPI, Flask, Django, or any ASGI or WSGI app on Vercel Functions with zero configuration, and find guides on background jobs, storage, AI workloads, containers, and migrating from other platforms. - [Enterprise Apps and Agents](/kb/enterprise): Explore how enterprises develop, deploy, and govern internal apps and AI agents. Learn about citizen development, shadow AI, access controls, and agent auditing, with practical guidance for turning employee-built tools into supported business applications. - [Jev from TypeSafe AI](/kb/jev-from-typesafe-ai): Jev is TypeSafe AI's System One model for fast, typed decisions. It evaluates supplied context and returns choices, scores, and probabilities that applications can use to classify requests, route tasks, and assess proposed actions without generating prose. - [Vercel Sandbox](/kb/vercel-sandbox): The compute primitive designed to safely run untrusted or user-generated code on Vercel.