Schlett, LauraLauraSchlett0009-0009-8914-25692026-01-142026-01-142025https://fis.uni-bamberg.de/handle/uniba/112141Catalogs Are Like Onions: UX Modifications in the Bavarian “Layered” Model (Laura Schlett | University of Bamberg) VuFind is being introduced as the new library catalog (OPAC) in the Bavarian Library Network (Bibliotheksverbund Bayern, BVB), replacing TouchPoint, as part of our transition from the legacy SISIS system to FOLIO. For VuFind development, we adopt a „layered“ Onion approach that separates local modifications from those applicable across the BVB and the base system. Each library can customize its local layer to integrate its Corporate Design and make other necessary changes, but leaves the bulk of the code untouched, allowing for network-wide updates. Themes and configurations are customizable by overriding a shared base, but module code is uniform; some optional features can be activated through configuration. Smaller libraries may delegate development to the BVB head office, which will provide basic customization. Larger libraries, like those at TU Munich (TUM) and the University of Bamberg, can perform more complex customizations or contribute to BVB code development. Bamberg University Library will complete its switch from TouchPoint to VuFind in August 2025, ahead of SISIS’s replacement by FOLIO in January 2026, while the TU Munich introduced both VuFind and FOLIO in January 2025. Our layered approach aims to balance flexibility for individual libraries with uniform development, deployment, and upgrades. Let’s have a closer look at the mobile design at the University of Bamberg and at the TUM, to see how that works out in practice!engVuFindOpen-SourceLibrarySoftware development004conferenceobjecthttps://blog.sbb.berlin/vufind2025/urn:nbn:de:bvb:473-irb-112141x