Using Concept Traceability to Investigate UML Class Diagram Evolution in Long-Existing FOSS Projects
Zaki Pauzi, Andrea Capiluppi · 2025
Traceability of design artifacts is key to software maintainability, yet little empirical evidence exists on UML model evolution in long existing FOSS projects. We refreshed a 2017 dataset, comprising 251 graphic class diagrams across 81 projects, with 735 diagrams from December 2024. Despite a nearly three-fold increase in raw diagram count, our concept-tracing analysis found virtually no substantive maintenance: early results show most diagrams remained unchanged or experienced only cosmetic updates. Only one diagram update corresponded to a security design proposal. These findings suggest UML dormancy, highlighting a disconnect between model intent and practice in Free and Open Source software (FOSS) development.