While federated identity has proven powerful in domain-based research activities, its deployment across the broad and diverse communities that libraries serve has been hampered by significant gaps in tools and standards. With unique requirements in privacy and the need to serve many different types of users, the challenges in implementing federated identity at scale for libraries have been significant. Those gaps are being addressed now and the missing pieces can be assembled. With an open standard for discovery, new attribute bundles for access control and privacy, and tools for users to manage those attributes, there is now a deploying infrastructure for federated identity for library needs. This presentation will bring together those pieces into an integrated demo environment called sliced bread. Using Seamless Access, new attribute tags for library needs from FIM4L, and CAR for notice and consent, we will walk the end-to-end user journey for different types of users with diverse privacy and security requirements. Finally we’ll look at the management interfaces that allow administration and reporting for librarians and IT.