+++
title="Build your very first app with buildpacks"
aliases=[
  "/docs/app-developer-guide/build-an-app",
  "/docs/using-pack/building-app/",
]
weight=1
+++

Building an app using Cloud Native Buildpacks is as easy as `1`, `2`, `3`...

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### 1. Select a builder

To [build][build] an app you must first decide which [builder][builder] you're going to use. A builder
includes the [buildpacks][buildpack] that will be used as well as the environment for building your
app.

When using `pack`, you can run `pack builder suggest` for a list of suggested builders.

```
pack builder suggest
```
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For this guide we're actually going to use a sample builder, `cnbs/sample-builder:resolute`, which is not listed
as a suggested builder for good reason. It's a sample.

### 2. Build your app

Now that you've decided on what builder to use, we can build our app. For this example we'll use our [samples][samples]
repo for simplicity.

1. Check that the samples repo exists and if not - we clone it
```
ls samples || git clone https://github.com/buildpacks/samples
```
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2. Build the app
```
pack build sample-app --path samples/apps/java-maven --builder cnbs/sample-builder:resolute
```
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> **TIP:** If you don't want to keep specifying a builder every time you build, you can set it as your default
> builder by running `pack config default-builder <BUILDER>` for example `pack config default-builder cnbs/sample-builder:resolute`
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### 3. Run it

```
docker run --rm -p 8080:8080 sample-app
```
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**Congratulations.**

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The app should now be running and accessible via [localhost:8080](http://localhost:8080).
<!--+end+-->

## What about ARM apps?

Linux ARM image builds are now supported.

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<a href="/docs/for-app-developers/how-to/special-cases/build-for-arm" class="button bg-blue">Linux ARM build guide</a>
<!--+end+-->

<!--+ `
Check out the [Linux ARM build guide](https://buildpacks.io//docs/for-app-developers/how-to/special-cases/build-for-arm).
` +-->
## What about Windows apps?

Windows image builds are now supported.

<!--+- if false+-->
<a href="/docs/for-app-developers/how-to/special-cases/build-for-windows" class="button bg-blue">Windows build guide</a>
<!--+end+-->
<!--+ `
Check out the [Windows build guide](https://buildpacks.io/docs/for-app-developers/how-to/special-cases/build-for-windows/).
` +-->

[build]: /docs/for-app-developers/concepts/build
[builder]: /docs/for-platform-operators/concepts/builder
[buildpack]: /docs/for-platform-operators/concepts/buildpack
[samples]: https://github.com/buildpacks/samples