This case study details how Tapjoy, a mobile ad network, utilized Honeycomb to enhance their observability during critical service migrations. Tapjoy's infrastructure includes a monolithic Rails application and numerous third-party attribution partners, processing millions of requests per minute. The engineers sought greater visibility into the migration process and the ability to investigate issues across high-cardinality fields. By implementing Honeycomb's Go library and NGINX agent, they achieved significant improvements in monitoring their API services. The case study highlights the reduction in time taken for service cutovers, decreasing from several days to just a few hours. This efficiency allowed the Tapjoy team to confidently manage migrations in real-time, quickly identifying and resolving issues as they arose. The use of Honeycomb not only streamlined their processes but also enhanced collaboration with partner organizations, leading to a more effective and timely integration experience.