> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dcdeploy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Deploy NestJS on DCDeploy

> Guide for deploying NestJS applications on DCDeploy using Docker or build-from-code

This guide walks you through deploying a **NestJS** application on DCDeploy, including setup, Docker configuration, environment variables, and recommended practices.

***

## Quick Start: Hello World

You can deploy a minimal NestJS app to test the workflow.

1. Create a new NestJS project locally:
   ```bash theme={null}
   npm i -g @nestjs/cli
   nest new hello-dcdeploy
   cd hello-dcdeploy
   ```
2. Modify src/app.controller.ts (or similar) to return a simple message:

```ts theme={null}

import { Controller, Get } from '@nestjs/common';

@Controller()
export class AppController {
  @Get()
  getHello(): string {
    return 'Hello DCDeploy from NestJS!';
  }
}
```

3. Test locally:

```bash theme={null}
npm run start
```

Access at [http://localhost:3000](http://localhost:3000).
4\. Push to GitHub or your Git provider:

```bash theme={null}
git init
git add .
git commit -m "Initial NestJS commit"
git branch -M main
git remote add origin https://github.com/your-username/hello-nestjs
git push -u origin main
```

Deploy on DCDeploy using steps in the guide below.

## Overview

NestJS is a progressive, extensible framework for building efficient, scalable server-side applications in Node.js. It uses TypeScript by default and supports modular architecture, dependency injection, and multiple transport layers.

On DCDeploy, you can deploy NestJS applications using:

* Build-from-code (auto-detecting Node.js projects)
* Dockerfile — for custom control over build, runtime, and dependencies

## Prerequisites

* A NestJS project (with TypeScript)
* package.json must have correct scripts like start, build, etc.
* A GitHub (or Git) repo containing your project
* If using Docker, a Dockerfile in project root
* Knowledge of environment variables for DB credentials, etc.

## Step-by-Step Guide

1. Prepare Your NestJS App

* Ensure the app listens on 0.0.0.0 on process.env.PORT || 3000.
* Replace any hardcoded DB credentials / secrets with environment variables.

2. (Optional) Dockerfile
   Here’s a sample `Dockerfile:`

```dockerfile theme={null}
FROM node:18-alpine AS builder

WORKDIR /app
COPY package*.json ./
RUN npm install --production
COPY . .
RUN npm run build

FROM node:18-alpine
WORKDIR /app
COPY --from=builder /app ./
EXPOSE 3000
CMD ["node", "dist/main"]
```

3. Push Code to Git
   Commit your code, tag your branch (e.g. main).
   Ensure .dockerignore excludes node\_modules, dist, etc.

4. Deploy on DCDeploy

* In DCDeploy dashboard → Navigate to the environment → Deploy tab
* Add a new service → Choose Build from Code (or Docker if using custom image).
* Provide repo URL, branch/ref.
* Set port 3000, ensure listening address 0.0.0.0.
* Choose protocol (HTTP/HTTPS), region(s).
* Configure environment variables needed (e.g. DB\_HOST, DB\_USER, DB\_PASS, DB\_NAME).
* Select machine type (CPU, RAM) based on expected load.
* Set minScale/maxScale as needed.
* Deploy and monitor logs & revision events.

## Example Service Config

```yaml theme={null}
services:
  nestjs-app:
    build:
      context: ./
      dockerfilePath: ./Dockerfile
      repo: your-username/hello-nestjs
      ref: main
      refType: branch
      autoBuild: true
    ports:
      - 3000
    protocol: https
    minScale: 1
    maxScale: 2
    environment:
      NODE_ENV: production
      DB_HOST: ${DB_HOST}
      DB_USERNAME: ${DB_USERNAME}
      DB_PASSWORD: ${DB_PASSWORD}
      DB_NAME: ${DB_NAME}
```

## Best Practices

* Use internal networking for connecting to databases or services within DCDeploy.
* Add a health check endpoint (e.g., /healthz) for better deployment monitoring.
* Set NODE\_ENV=production for performance optimizations.
* Keep the Docker image small (use Alpine or slim images, multi-stage builds).
* Use logging, and avoid exposing secrets in code.
* Use SSL / custom domain for secure access in production.

## Troubleshooting

| Problem                                       | Likely Cause                                              | Solution                                                                      |
| --------------------------------------------- | --------------------------------------------------------- | ----------------------------------------------------------------------------- |
| App not accessible after deployment           | App isn’t listening on `0.0.0.0` or wrong port configured | Check listening address & port in both NestJS code & DCDeploy service config. |
| Build fails due to missing TypeScript compile | Missing `build` script or dependencies                    | Ensure `npm run build` works locally; include `tsconfig`, etc.                |
| Environment variables not set or wrong        | Variables missing in DCDeploy dashboard                   | Add required env vars accurately.                                             |
| Slow cold start or high memory usage          | Large dependencies, SSR, or unoptimized build             | Use slim base images, optimize dependencies, increase memory if needed.       |