The text explores the critical role of caching in modern software development, particularly within Continuous Integration (CI) and Continuous Deployment (CD) pipelines. It highlights the importance of caching for reducing computational costs, speeding up job runtimes, and minimizing environmental impact. The discussion emphasizes the necessity of effective cache purging strategies to ensure that users receive up-to-date content and avoid issues such as bugs or outdated information. Different caching patterns are examined, including content-based hashing, time-to-live policies, and least recently used eviction strategies, all aimed at maintaining efficient and reliable systems. The text also delves into runtime caching for delivering fast user experiences post-deployment, covering strategies for managing static assets and application configurations through content delivery networks (CDNs). Best practices for cache invalidation are suggested, such as simulating purges before application, monitoring purge failures, and ensuring consistent caching behavior across different environments. Overall, the text underscores the importance of a comprehensive caching strategy to enhance application performance and reliability.