Beyond repositories: enabling actionable FAIR open data reuse services in particle physics

We describe experiences from building and operating the CERN Open Data repository platform that manages and disseminates more than one petabyte of open data from particle physics. We discuss the education and research use cases of the platform and we argue that in order to make the FAIR open data fully actionable and reusable by a variety of users, the research data repositories should evolve from focusing on resource-hosting present towards integrated service-provisioning future. We describe examples of an on-demand containerised analysis workflow execution environment that permits users to instantiate and explore the preserved open data in a virtually ``in situ'' manner. We discuss the reuse challenges and the technology solutions designed to overcome them. The developed tools take inspiration from reproducible science practices in the particle physics and life science domains and are applicable to any scientific discipline and any research data repository platform.