---
title: "Deploy NestJS over MCP with while.sh"
url: https://while.sh/en/guides/deploy-nestjs/
author: "Aloïs Oddon, co-founder of Nextmap"
updated: 2026-11-02
---

# Deploy a NestJS API from your AI agent, over MCP

Your AI agent wrote your NestJS API. Connected to while over MCP, it also deploys it, over HTTPS, without touching its code.

## Prerequisites

- A NestJS API, with its build and start:prod scripts.
- An AI agent that works in a terminal: Claude Code, Codex, Cursor or Gemini CLI.

## Step 1: Give your agent these instructions

Open your agent in your API's folder and paste these instructions into it:

```text titre="Instructions"
Connect to while with my account (while.sh/agents), then deploy my app.
```

Without an account, your agent deploys your API as a trial, in one request. To keep it, open the link it gives you and create your account.

With your account, your agent adds while's MCP server itself. If it asks you to, restart it. On the first call to while, a page opens in your browser. In Claude Code, if it doesn't open, type /mcp, choose while, then Authenticate. On that page, choose your app, or "A new app", then click Authorize.

## Step 2: Open your API

Your agent gives you your API's address, for example `https://mon-api.while.cloud`, over HTTPS.

## What your agent does

It writes while.yaml at the root of your API:

```yaml titre="while.yaml"
apiVersion: while/v1
project: mon-api
services:
  - name: web
    port: 3000
    health:
      path: /
```

Port 3000 is the one a new NestJS project uses, and its `main.ts` reads the `PORT` variable first (source 2). Your API is built, its tests run, then it starts with `start:prod`. The official starter project deploys on while as is, in a minute (source 1).

## Add a database

> You, to your agent: Add a PostgreSQL database.

Your agent declares the database in while.yaml, and its address reaches your code in `DATABASE_URL`. It is backed up every day, and can go back to a precise moment if needed.

## Speed things up with a cache

> You, to your agent: Add a cache for the most-read pages.

Your agent declares a Redis-compatible cache, connected to your code with its password.

## Restrict your API to your colleagues

> You, to your agent: Restrict the API to people in the company.

Your agent adds two lines to the service:

```yaml titre="while.yaml"
    access: internal
    email_domains: [acme.com]
```

Once your Google Workspace or Microsoft 365 is connected to while, on the Pro plan, your colleagues open the API with their usual account, and your code receives their name and email address, with no sign-in page to write.

## Move to your own domain

> You, to your agent: Put the API on api.acme.com.

Your agent declares the domain, you add the DNS records it gives you, and the HTTPS certificate follows.

## See a new version before you deploy it

> You, to your agent: Show me the new version before you deploy it.

Your agent opens a preview, at its own address, with its own data. You look at it, then your agent puts it into production.

## Go back to the previous version

> You, to your agent: Go back to the previous version.

In the 30 minutes after a deployment, the previous version comes back in a second. After that, it takes a few seconds. Once the previous version is back, your agent reads what broke in while's logs, fixes it and deploys again.

## Next steps

- [Deploy a Node.js API and its PostgreSQL database](/en/guides/deploy-node-api-postgresql/)
- [Run a scheduled job](/en/guides/run-cron-job/)
- [Compare the hosts that have an MCP server](/en/comparisons/mcp-hosting-claude-code/)

## Sources

1. [NestJS, the TypeScript starter project and its scripts (build, start:prod)](https://github.com/nestjs/typescript-starter), 2026-11-02
2. [NestJS, first steps (main.ts, port 3000 or the PORT variable)](https://docs.nestjs.com/first-steps), 2026-11-02

## Questions

### Do I need to change my project's scripts?

No, NestJS's start:prod script takes priority, as in the starter project.

### Do my tests run?

Yes, at every deployment, and a version that fails doesn't replace the previous one.

### Prisma or TypeORM?

Both read the database address from DATABASE_URL.