Al Istiqomah Mosque is a renovation project for a pesantren mosque in Sumedang, West Java. The mosque supports the daily worship activities of Boarding School Al Munawwarah Foundation, while giving the existing building a clearer architectural presence. The design uses simple geometric gestures on its massing, façade, and tower, creating a calm expression without removing the local character of the place. Clay breeze blocks are used as an important material element, filtering light and air while forming a warm tropical atmosphere. Through this intervention, the mosque becomes a modest, open, and peaceful space for worship.