Medallia, a California-based company focused on capturing feedback signals to enhance customer experiences, has successfully unified its observability stack using Grafana. Facing challenges with divergent systems about a decade ago, Medallia's Performance and Observability Engineering team embarked on a six-year journey involving trial and error to centralize their observability tools. Initially relying on a cloud metrics platform, they transitioned to an internal system using the TICK stack and later incorporated Grafana as the visualization layer due to its support for multiple data sources. This transition helped Medallia address issues related to costs and expandability, eventually adopting Thanos to enable long-term data retention and improve querying capabilities. With Grafana as the central hub, Medallia can now efficiently manage 250 million active time series metrics across 21 environments and deliver significant insights to engineering leadership, enhancing decision-making quality at higher organizational levels. The company continues to explore integrating additional open-source tools like OpenTelemetry, Grafana Mimir, and Grafana Tempo to further optimize their observability stack.