--- title: Backends on Vercel product: vercel url: /docs/frameworks/backend canonical_url: "https://vercel.com/docs/frameworks/backend" last_updated: 2026-06-22 type: conceptual prerequisites: - /docs/frameworks related: - /docs/fluid-compute - /docs/functions/usage-and-pricing - /docs/instant-rollback - /docs/vercel-firewall - /docs/deployments/environments summary: Vercel supports a wide range of the most popular backend frameworks, optimizing how your application builds and runs no matter what tooling you use. install_vercel_plugin: npx plugins add vercel/vercel-plugin --- # Backends on Vercel Backends deployed to Vercel receive the benefits of Vercel's infrastructure, including: ## Related pages > **For AI agents:** Follow these links to understand how this page connects to the rest of the Vercel ecosystem. For the full cross-link map (inbound, outbound, prerequisites, and semantic neighbors), see the .graph.md link below. - [Efficiently manage database connection pools with Fluid compute](https://vercel.com/kb/guide/efficiently-manage-database-connection-pools-with-fluid-compute?from=related) — How to create high-performance database connection pools without leaking connections - [How to gradually roll out new versions of your backend](https://vercel.com/kb/guide/how-to-gradually-roll-out-new-versions-of-your-backend?from=related) — Incrementally release updates to your backend to minimize impact of mistakes. - [Build an MCP Server with Weather tools using Express and Vercel](https://vercel.com/kb/guide/mcp-server-with-weather-tool-express?from=related) — Make your Express weather API accessible to AI assistants through the Model Context Protocol. - [How to ship an H3 app on Vercel](https://vercel.com/kb/guide/ship-a-h3-app-on-vercel?from=related) — Deploy an H3 app to Vercel with zero configuration. Learn to configure streaming, middleware, cron jobs, the Bun runtime - [How Vercel Services run on Fluid compute](https://vercel.com/kb/guide/vercel-services-fluid-compute?from=related) — The backends in a Vercel Services project run as Vercel Functions on Fluid compute by default. Learn how optimized concu - [Functions](https://vercel.com/docs/functions?from=related) — Run server-side code on Vercel without managing a server. - [Request Lifecycle](https://vercel.com/docs/fundamentals/infrastructure?from=related) — Learn how Vercel routes, secures, and serves requests from your users to your application. - [All Frameworks](https://vercel.com/docs/frameworks/more-frameworks?from=related) — Learn about the frameworks that can be deployed to Vercel. Full cross-link map for this page: [/docs/frameworks/backend.graph.md](/docs/frameworks/backend.graph.md) - [Fluid compute](/docs/fluid-compute): Zero-configuration, optimized concurrency, dynamic scaling, background processing, automatic cold-start prevention, region failover, and more - [Active CPU pricing](/docs/functions/usage-and-pricing): Only pay for the CPU you use, not waiting for I/O (e.g. calling AI models, database queries) - [Instant Rollback](/docs/instant-rollback): Quickly revert to a previous production deployment - [Vercel Firewall](/docs/vercel-firewall): A robust, multi-layered security system designed to protect your applications - [Preview deployments with Deployment Protection](/docs/deployments/environments#preview-environment-pre-production): Secure your preview environments and test changes safely before production - [Rolling releases](/docs/rolling-releases): Gradually roll out backends to detect errors early ## Zero-configuration backends Deploy the following backends to Vercel with zero-configuration. - **Elysia**: Ergonomic framework for humans - [Deploy](https://vercel.com/new/clone?repository-url=https://github.com/vercel/vercel/tree/main/examples/elysia) - **Express**: Fast, unopinionated, minimalist web framework for Node.js - [Deploy](https://vercel.com/new/clone?repository-url=https://github.com/vercel/vercel/tree/main/examples/express) | [View Demo](https://express-vercel-example-demo.vercel.app/) - **FastAPI**: FastAPI framework, high performance, easy to learn, fast to code, ready for production - [Deploy](https://vercel.com/new/clone?repository-url=https://github.com/vercel/vercel/tree/main/examples/fastapi) | [View Demo](https://vercel-fastapi-gamma-smoky.vercel.app/) - **Fastify**: Fast and low overhead web framework, for Node.js - [Deploy](https://vercel.com/new/clone?repository-url=https://github.com/vercel/vercel/tree/main/examples/fastify) - **Flask**: The Python micro web framework - [Deploy](https://vercel.com/new/clone?repository-url=https://github.com/vercel/vercel/tree/main/examples/flask) - **H3**: Universal, Tiny, and Fast Servers - [Deploy](https://vercel.com/new/clone?repository-url=https://github.com/vercel/vercel/tree/main/examples/h3) - **Hono**: Web framework built on Web Standards - [Deploy](https://vercel.com/new/clone?repository-url=https://github.com/vercel/vercel/tree/main/examples/hono) | [View Demo](https://hono.vercel.dev) - **Koa**: Expressive middleware for Node.js using ES2017 async functions - [Deploy](https://vercel.com/new/clone?repository-url=https://github.com/vercel/vercel/tree/main/examples/koa) - **NestJS**: Framework for building efficient, scalable Node.js server-side applications - [Deploy](https://vercel.com/new/clone?repository-url=https://github.com/vercel/vercel/tree/main/examples/nestjs) - **Nitro**: Nitro is a next generation server toolkit. - [Deploy](https://vercel.com/new/clone?repository-url=https://github.com/vercel/vercel/tree/main/examples/nitro) | [View Demo](https://nitro-template.vercel.app) - **xmcp**: The MCP framework for building AI-powered tools - [Deploy](https://vercel.com/new/clone?repository-url=https://github.com/vercel/vercel/tree/main/examples/xmcp) | [View Demo](https://xmcp-template.vercel.app/) To process background tasks with Python, you can [deploy a Celery app](/docs/frameworks/backend/celery) whose workers run as queue-triggered Vercel Functions. ## Adapting to Serverless and Fluid compute If you are transitioning from a fully managed server or containerized environment to Vercel’s serverless architecture, you may need to rethink a few concepts in your application since there is no longer a server always running in the background. The following are generally applicable to serverless, and therefore Vercel Functions (running with or without Fluid compute). ### WebSockets Vercel Functions can serve WebSocket connections when [Fluid compute](/docs/fluid-compute) is enabled. WebSocket connections follow [Vercel Function limits](/docs/functions/limitations), including maximum duration, so clients should handle reconnects when a connection closes. Store persistent state, rooms, presence, and pub/sub coordination in an external data store instead of relying on in-memory state. Learn more in the [WebSockets documentation](/docs/functions/websockets). ### Database Connections To manage database connections efficiently, [use the `attachDatabasePool` function from `@vercel/functions`](/docs/functions/functions-api-reference/vercel-functions-package#database-connection-pool-management). --- [View full sitemap](/docs/sitemap)