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

# Source

> Contains information about the app’s source code and operations that can be run on it.

Optional in [single-runtime](/docs/configure-apps/app-reference/single-runtime-image#primary-application-properties) and [composable](/docs/configure-apps/app-reference/composable-image#primary-application-properties) images.

The following table shows the properties that can be set in `source`:

| Name         | Type                     | Required | Description                                                                                                                                                                                                                                                       |
| ------------ | ------------------------ | -------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `operations` | An operations dictionary |          | Operations that can be applied to the source code. See [source operations](/docs/configure-apps/source-operations).                                                                                                                                               |
| `root`       | `string`                 |          | The path where the app code lives. Useful for [multi-app setups](/docs/configure-apps/multi-app). <br />**Single-runtime image**: Defaults to the directory of the `.upsun/config.yaml` file. <br />**Composable image**: Defaults to the root project directory. |