Service Delivery Index: A Driver for Reliability

This post details the adoption and scaling of the Service Delivery Index (SDI-R) program at Slack. It explains how SDI-R, a composite metric of API availability and user workflow success, is used to drive reliability engineering. Key contributions include outlining the visibility and accountability mechanisms (leadership reporting, linking regressions to teams), detailing scaling tools (Webapp Ownership Tool, Omni), and describing organizational forums (Engineering Monday Meeting) for prioritization. It also highlights lessons learned regarding API request weighting, the benefits of service-specific alerting for maintainability, and the necessity of continuous metric evolution.