This article examines how the concept of Maqāṣid al-Sharīʿah, classically intended to guide individual juristic reasoning (ijtihād), has been reconstructed to fit modern, institutional, codified, and procedural legislative processes. The issue is significant given Indonesia's plural legal system, in which Islamic legal values coexist with national positive law, often generating tension between formal legality and substantive justice. The study employs a normative doctrinal legal method with statutory, conceptual, comparative, and philosophical approaches, drawing on primary, secondary, and tertiary legal materials gathered through library research and analyzed qualitatively through legal interpretation and comparative-conceptual analysis. The findings show that the modern reconstructions of Ibn ʿĀshūr and Jasser Auda have transformed Maqāṣid from a basis for individual rulings into a systemic framework applicable across three stages of national lawmaking: legislative preparation, norm formulation, and regulatory evaluation. This approach is examined in three empirical domains, namely Islamic family law, comparative Islamic criminal law, and Islamic financial regulation, each reflecting a distinct pattern of institutionalizing Maqāṣid-based reasoning. The study also identifies key design challenges, namely the risk of rigid literalism on the one hand and unaccountable discretion on the other, and proposes a normative convergence between Maqāṣid and Pancasila as a bridge for integrating the value of maṣlaḥah into the positive legal system without undermining legal certainty. The article recommends strengthening transparent procedural mechanisms, including a dedicated Maqāṣid impact assessment within academic papers accompanying bills, along with interdisciplinary collaboration in the legislative drafting process.