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

# Prebuilt OCI image

> Run an image built elsewhere without a source build on a Towbar server.

Choose `image` when CI or another system already produces the container. Use an explicit version tag or immutable digest; `latest` is rejected. Towbar resolves tags to digests before execution and rejects a digest change during deployment.

## Example manifest

This is the validated example from the Towbar `examples/platform-modes` project. Replace the documentation IP, domain, and image choices with values for your environment.

```yaml title=".towbar/apps/image.app.yml" theme={"system"}
id: image-example
name: Prebuilt image example
buildServer: null
deployment:
  type: image
  image: nginxinc/nginx-unprivileged@sha256:27985295bdb22a1ef8f712863210bd5877c0f3006494a593e86b3fe0fa55467e
  platform: linux/amd64
container:
  port: 8080
health:
  path: /
environments:
  production:
    server: 192.0.2.10
```

## Configure it

The example uses an immutable nginx digest and sets `buildServer: null` because no source build is needed. Match `container.port` and `health.path` to the image. A private image can reference an enabled OCI registry integration with `deployment.registry`.

A new image digest is a new deployment input. Pin the architecture with `deployment.platform` when the image or target requires it. Image rollback selects an earlier image; it does not reverse database migrations or persistent data changes.

Map the named environment to a branch, register and prepare its server, then sync the repository. Start with a manual deployment and verify the running service before opting into automation. See [Application manifest](/docs/apps/manifest) for shared fields and [Deployment modes](/docs/platform-deployments) to compare modes.