aws-cdk

AWS CDK TypeScript

Overview

Use this skill to build AWS infrastructure in TypeScript with reusable constructs, safe defaults, and a validation-first delivery loop.

When to Use

Use this skill when:

• Creating or refactoring a CDK app, stack, or reusable construct in TypeScript
• Choosing between L1, L2, and L3 constructs
• Building serverless, networking, or security-focused AWS infrastructure
• Wiring multi-stack applications and environment-aware deployments
• Validating infrastructure changes with cdk synth, tests, cdk diff, and cdk deploy

Instructions

1. Project Initialization

# Create a new CDK app
npx cdk init app --language typescript

# Project structure
my-cdk-app/
├── bin/
│   └── my-cdk-app.ts          # App entry point (instantiates stacks)
├── lib/
│   └── my-cdk-app-stack.ts    # Stack definition
├── test/
│   └── my-cdk-app.test.ts     # Tests
├── cdk.json                    # CDK configuration
├── tsconfig.json
└── package.json

2. Core Architecture

import { App, Stack, StackProps, CfnOutput, RemovalPolicy } from 'aws-cdk-lib';
import { Construct } from 'constructs';
import * as s3 from 'aws-cdk-lib/aws-s3';

// Define a reusable stack
class StorageStack extends Stack {
  public readonly bucketArn: string;

  constructor(scope: Construct, id: string, props?: StackProps) {
    super(scope, id, props);

    const bucket = new s3.Bucket(this, 'DataBucket', {
      versioned: true,
      encryption: s3.BucketEncryption.S3_MANAGED,
      removalPolicy: RemovalPolicy.RETAIN,
      blockPublicAccess: s3.BlockPublicAccess.BLOCK_ALL,
    });

    this.bucketArn = bucket.bucketArn;
    new CfnOutput(this, 'BucketName', { value: bucket.bucketName });
  }
}

// App entry point
const app = new App();

new StorageStack(app, 'DevStorage', {
  env: { account: process.env.CDK_DEFAULT_ACCOUNT, region: 'us-east-1' },
  tags: { Environment: 'dev' },
});

new StorageStack(app, 'ProdStorage', {
  env: { account: '123456789012', region: 'eu-west-1' },
  tags: { Environment: 'prod' },
  terminationProtection: true,
});

app.synth();