The authors present a tutorial on Custos, a cybersecurity service based on open source software that helps science gateways manage user identities, integrate with federated authentication systems, manage secrets such as OAuth2 access tokens and SSH keys needed to connect to remote resources, and manage groups and access permissions to digital objects. This tutorial will provide an overview of Custos’s capabilities, provide hands-on exercises on using its features, demonstrate to gateway providers how to integrate the services into their gateways with software development kits for the Custos API, introduce developers to the code and how to review and contribute to it, supply gateway providers with information on how Custos services are deployed for high availability and fault tolerance, and how Custos operations handle incidence response. This tutorial builds on a successful online tutorial presented by the authors at Gateways 2020; see https://www.youtube.com/watch?v=CuBvFj194Kg for a recording.
