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This is the SST v0.x Constructs doc. SST v1 is now released. If you are using v1, see the v1 Constructs doc. If you are looking to upgrade to v1, check out the migration steps.

The DebugStack construct is used internally to create the resources needed to power Live Lambda Development. Note that, the DebugStack construct should only be created inside the DebugApp.

It extends cdk.Stack. It automatically prefixes the stack names with the stage and app name to ensure that they can be deployed to multiple regions in the same AWS account. It also ensures that the stack uses the same AWS profile and region as the app.


new DebugStack(scope: Construct, id: string, props: StackProps)



Adding to an app

Add it to your app in stacks/index.js.

import { DebugStack } from "@serverless-stack/resources";

export function debugApp(app) {
new DebugStack(app, "debug-stack");

// Customize debug stack

Here app is an instance of DebugApp.

Note that, setting the env for the debug stack is not allowed.

new MyStack(app, "my-stack", { env: { account: "1234", region: "us-east-1" } });

It will throw an error.

Error: Do not directly set the environment for a stack

This is by design. The stacks in SST are meant to be re-deployed to multiple stages. And so they depend on the region and AWS profile that's passed in through the CLI. If a stack is hardcoded to be deployed to a specific account or region, it can break your deployment pipeline.

Accessing app properties

The stage, region, and app name can be accessed through the app object. In your stacks/index.js you can use.

export function debugApp(app) {
new DebugStack(app, "debug-stack");


You can use this to conditionally add stacks or resources to your app.

Prefixing resource names

You can optionally prefix resource names to make sure they don't thrash when deployed to different stages in the same AWS account.

You can do so in your stacks.

scope.logicalPrefixedName("MyResource"); // Returns "dev-my-sst-app-MyResource"

This invokes the logicalPrefixedName method in DebugApp that the DebugStack is added to. This'll return dev-my-sst-app-debug-stack, where dev is the current stage and my-sst-app is the name of the app.

Configuring the debug stack

export function debugApp(app) {
new DebugStack(app, "debug-stack", {
stackName: app.logicalPrefixedName("my-debug-stack"),
payloadBucketArn: "arn:aws:s3:::my-bucket",
websocketHandlerRoleArn: "arn:aws:iam::123456789012:role/my-role",

Tagging the debug stack

import * as cdk from "aws-cdk-lib";

export function debugApp(app) {
new sst.DebugStack(app, "debug-stack");
cdk.Tags.of(app).add("my-tag", `${app.stage}-${app.region}`);


Takes the following construct props in addition to the cdk.StackProps.


Type : string, defaults to a new bucket will be created

By default, an S3 bucket is created as temporary storage for passing large requests/responses between the client and the Lambda Function. You can provide the ARN of an existing S3 bucket.


Type : string, defaults to new roles will be created

This is the role that will be assumed by the WebSocket API handler function. It controls the permissions that the function will have. The role must be assumable by the service principal.