# CombineStrategyOptions

Options for the combine strategy.

- Source: [`core/lib/mixins/property-merge-strategy.ts`](https://github.com/aws/aws-cdk/blob/v2.275.0/packages/aws-cdk-lib/core/lib/mixins/property-merge-strategy.ts#L124)
- Type last changed: v2.254.0 · 13 May 2026

## Example

```ts
// TableV2 uses a Box internally for replicas.
// The mixin defers the merge and appends the new replica at synthesis time.
const table = new dynamodb.TableV2(scope, 'Table', {
  partitionKey: { name: 'pk', type: dynamodb.AttributeType.STRING },
  // L2 prop: pointInTimeRecovery is a boolean
  replicas: [{ region: 'us-east-1', pointInTimeRecovery: true }],
});

// Mixins always use L1 (CloudFormation) property names and shapes,
// regardless of what the L2 API looks like.
table.with(new CfnGlobalTablePropsMixin({
  replicas: [{
    region: 'eu-west-1',
    // L1 prop: pointInTimeRecoverySpecification is an object
    pointInTimeRecoverySpecification: { pointInTimeRecoveryEnabled: true },
  }],
}, { strategy: PropertyMergeStrategy.combine({ arrays: ArrayMergeStrategy.append() }) }));

// Result (synthesized CloudFormation):
// Replicas:
//   - Region: us-east-1
//     PointInTimeRecoverySpecification:
//       PointInTimeRecoveryEnabled: true
//   - Region: us-west-2        <-- primary region, added by L2
//   - Region: eu-west-1        <-- added by mixin
//     PointInTimeRecoverySpecification:
//       PointInTimeRecoveryEnabled: true
```

## Properties

- `arrays`: [IArrayMergeStrategy](/cdk/api/v2/docs/aws-cdk-lib.IArrayMergeStrategy.html) = ArrayMergeStrategy.replace() — Strategy for merging arrays.