In this article, Erez Rokah compares CircleCI with AWS CodeBuild for serverless applications and focuses on the advantages of using CircleCI. CircleCI offers several key benefits, including free private repository access, a mature and well-documented tool, integration with other development tools, relevant notifications, a REST API to manage build jobs, and a reproducible setup that allows adding new services with ease. In contrast to CodeBuild, CircleCI does not use CloudFormation to describe the deployment process, has no regions, requires giving CircleCI access to the AWS account, and handles email notifications and GitHub access tokens automatically. Erez Rokah sets up an advanced CICD process using CircleCI and provides a CLI tool that follows a GitHub project, connects it to AWS, and sets up environment variables and project settings. The setup includes different deployment stages, automated tests, and the ability to deploy specific services with their dependencies.