During November 2024, Lili Cosi refactored the custom labels example in the prometheus/client_golang repository, introducing two new components, FireKeeper and SparkForge, each instrumented with metrics for maintained fires, distributed sparks, and forged items. She focused on improving naming consistency and code readability, aligning the example with established best practices and reducing onboarding time for new contributors. Working primarily in Go, Lili enhanced the observability of the example by adding targeted metrics, supporting better monitoring and alerting. Her work emphasized code quality and maintainability, demonstrating skills in metrics instrumentation, system monitoring, and thoughtful refactoring without addressing major bug fixes.