Custom data sites and interactive resources provide researchers control over their work and support disciplinary data requirements. However, dispersed data storage results in broken links and lost data as researchers move and projects run out of funding. Institutions and libraries have the long-term sustainability to preserve content, but can only efficiently do so in a standardized repository. Our Invenio-based institutional data repository, CaltechDATA, demonstrates how an API-enabled data repository can support custom applications. Specific use cases for atmospheric observations and map data showcase the principle of developing at the edges of the repository system.