---
title: replaceWith
url: /docs/iac/concepts/resources/options/replacewith/
---
The `replaceWith` resource option allows you to force a replace operation on the current resource every time one of the given resources is replaced.

However, not all relationships are visible to Pulumi: perhaps there are differences in behavior between providers, or your application introduces its own specific relationships, such as two services that depend on one another and thus must always be replaced together.

In these cases, you can use `replaceWith` to make these relationships explicit to the Pulumi engine. In the following example, an explicit dependency is declared: whenever the database is replaced, we must also replace the server.

> **Applies to custom resources only.** The `replaceWith` resource option has no direct effect on [component resources](/docs/iac/concepts/components/). It is defined on the base resource-options type in every Pulumi SDK, so no SDK rejects it at compile time — passing it to a component resource has no direct effect at runtime.

<!-- chooser: language -->

<!-- option: typescript -->
```typescript
import * as pulumi from "@pulumi/pulumi";
import * as aws from "@pulumi/aws";

const database = new aws.rds.Instance('app-db', { /* ... */ });
const application = new aws.ec2.Instance('app-service', { /* ... */ }, {
  replaceWith: [database]
})

```

<!-- /option -->

<!-- option: python -->
```python
import pulumi
import pulumi_aws as aws

database = aws.rds.Instance('app-db', {})
application = aws.ec2.Instance('app-service', {},
    opts=pulumi.ResourceOptions(replace_with=[database])
)

```

<!-- /option -->

<!-- option: go -->
```go
import (
    "github.com/pulumi/pulumi-aws/sdk/v6/go/aws/ec2"
    "github.com/pulumi/pulumi-aws/sdk/v6/go/aws/rds"
    "github.com/pulumi/pulumi/sdk/v3/go/pulumi"
)

database, err := rds.NewInstance(ctx, "app-db", &rds.InstanceArgs{ ... })
if err != nil {
    return err
}

application, err := ec2.NewInstance(ctx, "app-service", &ec2.InstanceArgs{ ... },
    pulumi.ReplaceWith([]pulumi.Resource{database}))
if err != nil {
    return err
}

```

<!-- /option -->

<!-- option: csharp -->
```csharp
using Pulumi;
using Aws = Pulumi.Aws;

var database = new Aws.Rds.Instance("app-db", new() { ... });
var application = new Aws.Ec2.Instance("app-service", new() { ... }, new CustomResourceOptions
{
    ReplaceWith = new[]
    {
        database,
    },
});

```

<!-- /option -->

<!-- option: java -->
```java
import com.pulumi.aws.ec2.Instance;
import com.pulumi.aws.ec2.InstanceArgs;
import com.pulumi.resources.CustomResourceOptions;

var database = new com.pulumi.aws.rds.Instance("app-db",
    com.pulumi.aws.rds.InstanceArgs.builder()
        .build());

var application = new Instance("app-service",
    InstanceArgs.builder()
        .build(),
    CustomResourceOptions.builder()
        .replaceWith(database)
        .build());

```

<!-- /option -->

<!-- option: yaml -->
```yaml
resources:
  database:
    type: aws:rds:Instance
    properties:
      # ...
  application:
    type: aws:ec2:Instance
    properties:
      # ...
    options:
      replaceWith:
        - ${database}

```

<!-- /option -->

<!-- /chooser -->