> **Experimental**
>
> `@aws-cdk/aws-imagebuilder-alpha` is an [**experimental**](/stability) (alpha) package: its API may change in any release, without a major version bump.
# ScheduleStartCondition

The start condition for the pipeline, indicating the condition under which a pipeline should be triggered.

- Stability: [Experimental](/cdk/api/stability.html)
- Source: [`lib/image-pipeline.ts`](https://github.com/aws/aws-cdk/blob/v2.275.0-alpha.0/packages/@aws-cdk/aws-imagebuilder-alpha/lib/image-pipeline.ts#L321)

## Example

```ts
const advancedSchedulePipeline = new imagebuilder.ImagePipeline(this, 'AdvancedSchedulePipeline', {
  recipe: exampleImageRecipe,
  schedule: {
    expression: events.Schedule.rate(Duration.days(7)),
    // Only trigger when dependencies are updated (new base images, components, etc.)
    startCondition: imagebuilder.ScheduleStartCondition.EXPRESSION_MATCH_AND_DEPENDENCY_UPDATES_AVAILABLE,
    // Automatically disable after 3 consecutive failures
    autoDisableFailureCount: 3
  },
  // Start enabled
  status: imagebuilder.ImagePipelineStatus.ENABLED
});
```

## Members

| Member | Description |
| --- | --- |
| `EXPRESSION_MATCH_ONLY` | Indicates to trigger a pipeline whenever its schedule is met. |
| `EXPRESSION_MATCH_AND_DEPENDENCY_UPDATES_AVAILABLE` | Indicates to trigger a pipeline whenever its schedule is met, and there are matching dependency updates available, such as new versions of components or images to use in the pipeline build. |

## Referenced by

- [`ImagePipelineSchedule`](/v2/docs/@aws-cdk_aws-imagebuilder-alpha.ImagePipelineSchedule).startCondition