The tutorial provides a comprehensive guide on building, securing, and deploying a serverless application using AWS Lambda, DynamoDB, and CircleCI, with Terraform as the infrastructure management tool. It emphasizes the importance of enforcing security measures such as IAM least privilege, input validation, and XSS protection to prevent data breaches and protect sensitive information. The guide walks through setting up the project structure, configuring infrastructure using Terraform, and implementing CRUD operations with Node.js to manage real estate listings in DynamoDB, highlighting the use of Express, serverless-http, and AWS SDKs for development. It also outlines steps to integrate CircleCI for continuous integration and deployment, using environment variables to securely manage AWS credentials and automate testing, security scans, and infrastructure provisioning. The tutorial concludes with instructions on verifying the deployment through AWS Management Console and testing the API with Postman, offering readers a robust framework for developing secure and scalable serverless applications.