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

# nsc base-image build-github-image

Test the build of a base image.

`base-image build-github-image` performs a test build of a Dockerfile intended
for use as a GitHub Actions runner base image. It's useful for validating that
a custom image configuration builds successfully before you upload it or wire
it up to a GitHub runner profile. This command is also invokable as
`nsc github build-base-image` — both forms run the exact same command, so
don't be confused if you see either one referenced elsewhere.

## Usage

```bash theme={null}
nsc base-image build-github-image [--file string] [--os-label string] [--platform strings]
```

### Example

```bash theme={null}
nsc base-image build-github-image --file ./Dockerfile --os-label ubuntu-24.04 --platform linux/arm64
```

## Optional Flags

<h3 id="-f---file-string">
  -f, --file string
</h3>

Specifies what Dockerfile to build.

<h3 id="-l---os-label-string">
  -l, --os-label string
</h3>

Specifies the OS version of the base image. Default: `ubuntu-22.04`.

<h3 id="-p---platform-strings">
  -p, --platform strings
</h3>

Which platforms to build for (`linux/amd64` or `linux/arm64`). Default:
`linux/amd64,linux/arm64`.

## Related Topics

* [nsc github profile test-build-base-image](/docs/reference/cli/github-profile-test-build-base-image) - Build the base image from a GitHub runner profile's Dockerfile
* [nsc base-image upload](/docs/reference/cli/base-image-upload) - Convert an existing image into a base image and upload it to nscr.io
* [nsc base-image optimize](/docs/reference/cli/base-image-optimize) - Optimize a base image for fast worker boot