---
title: Containerize a Node.js application
linkTitle: Containerize your app
weight: 10
keywords: node.js, node, containerize, initialize
description: Learn how to containerize a Node.js application.
aliases:
  - /get-started/nodejs/build-images/
  - /language/nodejs/build-images/
  - /language/nodejs/run-containers/
  - /language/nodejs/containerize/
  - /guides/language/nodejs/containerize/
---

## Prerequisites

- You have installed the latest version of [Docker
  Desktop](/get-started/get-docker.md).
- You have a [git client](https://git-scm.com/downloads). The examples in this
  section use a command-line based git client, but you can use any client.

## Overview

This section walks you through containerizing and running a Node.js
application.

## Get the sample application

Clone the sample application to use with this guide. Open a terminal, change
directory to a directory that you want to work in, and run the following command
to clone the repository:

```console
$ git clone https://github.com/docker/docker-nodejs-sample && cd docker-nodejs-sample
```

## Initialize Docker assets

Now that you have an application, you can create the necessary Docker assets to
containerize your application. You can use Docker Desktop's built-in Docker Init
feature to help streamline the process, or you can manually create the assets.

{{< tabs >}}
{{< tab name="Use Docker Init" >}}

Inside the `docker-nodejs-sample` directory, run
the `docker init` command in a terminal. `docker init` provides some default
configuration, but you'll need to answer a few questions about your application.
Refer to the following example to answer the prompts from `docker init` and use
the same answers for your prompts.

```console
$ docker init
Welcome to the Docker Init CLI!

This utility will walk you through creating the following files with sensible defaults for your project:
  - .dockerignore
  - Dockerfile
  - compose.yaml
  - README.Docker.md

Let's get started!

? What application platform does your project use? Node
? What version of Node do you want to use? 18.0.0
? Which package manager do you want to use? npm
? What command do you want to use to start the app: node src/index.js
? What port does your server listen on? 3000
```

{{< /tab >}}
{{< tab name="Manually create assets" >}}

If you don't have Docker Desktop installed or prefer creating the assets manually, you can create the following files in your project directory.

Create a file named `Dockerfile` with the following contents.

```dockerfile {collapse=true,title=Dockerfile}
# syntax=docker/dockerfile:1

# Comments are provided throughout this file to help you get started.
# If you need more help, visit the Dockerfile reference guide at
# https://docs.docker.com/go/dockerfile-reference/

# Want to help us make this template better? Share your feedback here: https://forms.gle/ybq9Krt8jtBL3iCk7

ARG NODE_VERSION=18.0.0

FROM node:${NODE_VERSION}-alpine

# Use production node environment by default.
ENV NODE_ENV production


WORKDIR /usr/src/app

# Download dependencies as a separate step to take advantage of Docker's caching.
# Leverage a cache mount to /root/.npm to speed up subsequent builds.
# Leverage a bind mounts to package.json and package-lock.json to avoid having to copy them into
# into this layer.
RUN --mount=type=bind,source=package.json,target=package.json \
    --mount=type=bind,source=package-lock.json,target=package-lock.json \
    --mount=type=cache,target=/root/.npm \
    npm ci --omit=dev

# Run the application as a non-root user.
USER node

# Copy the rest of the source files into the image.
COPY . .

# Expose the port that the application listens on.
EXPOSE 3000

# Run the application.
CMD node src/index.js
```

Create a file named `compose.yaml` with the following contents.

```yaml {collapse=true,title=compose.yaml}
# Comments are provided throughout this file to help you get started.
# If you need more help, visit the Docker Compose reference guide at
# https://docs.docker.com/go/compose-spec-reference/