50 AI Prompts for AWS Lambda and Serverless Architecture

Act as an AWS Lambda TypeScript expert.

Task:
Write a Lambda function handler for an API Gateway v2 HTTP API.

Endpoint: POST /users
Request body: { name: string, email: string, role: 'admin' | 'user' }

Handler requirements:
1. Parse and validate the request body (return 400 if invalid)
2. Generate a UUID for the new user
3. Put the user item in DynamoDB (table name from environment variable USERS_TABLE)
4. Return 201 with the created user object
5. Return 500 with a safe error message on any unhandled error
6. Use AWS Lambda Powertools Logger for structured logging

Use: TypeScript, AWS SDK v3 DynamoDBDocumentClient, @aws-lambda-powertools/logger,
     @types/aws-lambda for the APIGatewayProxyEventV2 type

Act as an AWS DynamoDB and TypeScript expert.

Task:
Write DynamoDB operations for a single-table design using SDK v3 DocumentClient.

Table design:
- Table name: app-table
- PK: pk (string), SK: sk (string)
- User items: PK=USER#userId, SK=PROFILE
- Order items: PK=USER#userId, SK=ORDER#orderId
- GSI: gsi1pk (status), gsi1sk (createdAt) for querying orders by status

Operations needed:
1. Get a user by userId
2. Get all orders for a user, sorted by createdAt descending
3. Create a user and their first order in a transaction
4. Update order status with a condition expression (only if current status is PENDING)
5. Query all orders with status PROCESSING using the GSI

Use: AWS SDK v3, DynamoDBDocumentClient, TypeScript

Act as an AWS API Gateway and Lambda expert.

Task:
Set up a JWT authorizer for an API Gateway HTTP API (v2).

Requirements:
- Use AWS Cognito User Pool as the JWT issuer
- Protect all routes except GET /health and POST /auth/login
- Extract the userId claim from the JWT and pass it to Lambda via
  requestContext.authorizer.jwt.claims
- Return 401 for missing token and 403 for invalid/expired token

Provide:
1. The AWS SAM template snippet for the JWT authorizer
2. How to read the userId in the Lambda handler
3. The IAM permission needed for the authorizer

Also provide a Lambda middleware wrapper that extracts userId from the
event and adds it to a typed context object for the handler to use.

Act as an AWS SAM expert.

Task:
Write an AWS SAM template for a CRUD REST API with the following resources:

Lambda functions (Node.js 20.x, 256MB, 30s timeout):
- GetUsers: GET /users
- CreateUser: POST /users
- GetUser: GET /users/{userId}
- UpdateUser: PUT /users/{userId}
- DeleteUser: DELETE /users/{userId}

DynamoDB table:
- Name: UsersTable, PK: userId (String), BillingMode: PAY_PER_REQUEST

Requirements:
- HTTP API (v2) with CORS enabled for https://myapp.com
- Least-privilege IAM policies (each function only gets the actions it needs)
- Environment variable USERS_TABLE injected into all functions
- Parameters: Environment (dev, staging, prod) with conditional table naming
- Output: ApiUrl and TableName

Use: SAM template format 2010-09-09, AWS::Serverless transform

Act as an AWS Lambda performance expert.

Task:
My Node.js Lambda function has a 3-second cold start. Help me reduce it.

Current setup:
- Runtime: Node.js 20.x
- Memory: 128MB
- Package size: 45MB (unzipped)
- SDK clients initialized inside the handler on every invocation
- Using ts-node/register at runtime (not pre-compiled)

Provide fixes for:
1. Bundle the function with esbuild to reduce package size
   (show the esbuild config and the SAM build configuration)
2. Move SDK client initialization outside the handler
   (show the correct module-level pattern)
3. Increase memory to reduce cold start duration
   (explain the memory-CPU relationship in Lambda)
4. Set up Provisioned Concurrency for the most critical endpoints
   (show the SAM template addition)

Target: under 500ms cold start for an API Gateway endpoint

Act as an AWS Lambda and S3 expert.

Task:
Write a Lambda function that processes uploaded images from S3.

Trigger: S3 ObjectCreated event on bucket uploads-bucket, prefix images/

Processing steps:
1. Download the uploaded image from S3
2. Resize to three sizes: 1200px (large), 600px (medium), 200px (thumbnail)
3. Convert all sizes to WebP format
4. Upload all three sizes to a different bucket: processed-bucket
   with prefix processed/[original-name]/
5. Write a record to DynamoDB with the original key, processed keys, and status

Use: TypeScript, AWS SDK v3, sharp for image processing
Avoid: putting output files back into uploads-bucket (would cause infinite loop)

Also provide the SAM template resource for this function.