Tiexin Guo, a Senior DevOps Consultant at Amazon Web Services, discusses the importance of managing infrastructure through code in DevOps, emphasizing the need for securing both the code and the infrastructure it manages. He highlights that infrastructure as code (IaC) tools like Terraform are pivotal in deploying cloud infrastructure, but stresses that security should be paramount, particularly in preventing sensitive information from being compromised. The article addresses various strategies to enhance security, such as separating environments to improve security boundaries, using Terraform modules to manage different environments, and employing secret managers rather than storing sensitive data in code. It also discusses the significance of automated security scanning tools to detect potential vulnerabilities and stresses the value of continuous learning and adhering to best practices for infrastructure security. The overall message underscores the need for rigorous security measures in DevOps to ensure robust protection of both the code and the infrastructure it governs.