Diah Putri Kartikasari and Farhan, M. 2025. Design and Implementation of a Web-Based Digital Repository System in the Muamalah Study Program at UINSU Using the Waterfall Method. Journal of Computer Science and Informatics Engineering . 4, 4 (Aug. 2025), 299–311. DOI:https://doi.org/10.55537/cosie.v4i4.1158.