The text discusses the adoption of distributed architecture in software systems, which enhances scalability and flexibility but introduces new points of failure, necessitating advanced testing methods beyond traditional ones. Chaos engineering is introduced as a solution, involving the intentional injection of faults into systems to test their resilience under stress, thereby allowing teams to uncover vulnerabilities and improve recovery strategies. Originating at Netflix in 2008 during its migration to AWS, chaos engineering has evolved, with tools like Chaos Toolkit and Gremlin facilitating the design of experiments to bolster system resilience. The text also provides a practical guide on integrating chaos engineering into a CI/CD pipeline using CircleCI and Chaos Toolkit, including setting up a Kubernetes environment, running chaos experiments locally, and automating these tests in a CI/CD pipeline to ensure continuous validation of application resilience. This approach is exemplified through a pod termination experiment that tests a system's self-healing capabilities, ensuring that resilience testing becomes a core component of the development lifecycle.