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

# Remote State

> Access outputs from other Terraform stacks.

Remote state allows you to share data between different Terraform configurations. In tfts, you can use `TerraformRemoteState` to read outputs from a previously deployed stack.

## Data Sources for Remote State

tfts provides several implementations of `TerraformRemoteState` depending on your backend:

* `DataTerraformRemoteStateLocal`: For local state files.
* `DataTerraformRemoteStateS3`: For state stored in Amazon S3.
* `DataTerraformRemoteStateGcs`: For state stored in Google Cloud Storage.
* `DataTerraformRemoteStateAzurerm`: For state stored in Azure Blob Storage.

## Accessing Outputs

Once you have defined a remote state data source, you can access its outputs using typed getter methods.

```typescript theme={null}
import { DataTerraformRemoteStateS3 } from "tfts";

const vpcState = new DataTerraformRemoteStateS3(stack, "vpc_state", {
  bucket: "my-terraform-state",
  key: "network/terraform.tfstate",
  region: "us-east-1",
});

const vpcId = vpcState.getString("vpc_id");
const privateSubnets = vpcState.getList("private_subnets");
```

Available methods include:

* `get(outputName)`
* `getString(outputName)`
* `getNumber(outputName)`
* `getList(outputName)`
* `getBoolean(outputName)`

## Cross-Stack References

If you are managing multiple stacks within the same `App`, you can use `app.crossStackReference()` to automatically handle the dependency and state sharing.

```typescript theme={null}
const networkStack = new NetworkStack(app, "network");
const appStack = new AppStack(app, "app");

// Accessing an output from networkStack in appStack
const vpcId = app.crossStackReference(appStack, networkStack, "vpcId");

new Instance(appStack, "web", {
  vpcId: vpcId,
  // ...
});
```

This pattern simplifies the management of shared resources by abstracting away the manual configuration of remote state data sources and outputs.