# Why does npm run start not work on Vercel?

**Author:** Matthew Sweeney

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When deploying your application with Vercel you are prompted for a build command. This command is intended to build your application to generate frontend assets that can be served by the Vercel CDN.

## No Running Servers

If your build command is `npm run start`, `node app.js`, `nodemon server.js`, or similar, it is likely you are trying to start a server for your application.

The Vercel platform is serverless and designed for static frontends and [Serverless Functions](https://vercel.com/docs/functions). **There is no running server**.

As a result of this, if you are trying to start a server, you are likely to run into difficulties either with your application not starting, or unexpected behavior.

## Serverless Functions

As an alternative to running a server, Vercel allows you to create Serverless Functions, which can be used to execute logic on the server side.

Serverless Functions are stateless and event-driven, which means that they are created to respond to a request and will no longer exist once the response has been sent.

Therefore, it is not possible to store state in-between requests. Any data that needs to be persisted must be stored in a database.

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