The text provides an in-depth exploration of how Merge, a company specializing in API integrations, successfully optimized its log processing system, resulting in a significant reduction in computational costs. Initially, the system faced inefficiencies due to the resource-intensive operation of a service called the "Payload Trimmer," which was running on numerous Kubernetes pods to manage large API logs in Elasticsearch. By employing Python profiling tools such as cProfile and line_profiler, Merge identified bottlenecks in their code, particularly the costly use of Python's deepcopy function. By switching to more efficient data structures like immutable tuples, Merge achieved a 5x performance increase in the trimming function and an 80% reduction in pod count, illustrating the importance of data-driven optimization and system-wide thinking in software engineering. The case study highlights the principles of profiling, data structure selection, and the iterative nature of optimization, ultimately demonstrating how local code improvements can lead to substantial system-wide benefits.