<![CDATA[Lump-Sum Design and Build contracts offer cost certainty and integrated project delivery, yet they often create significant governance challenges when project scope changes during infrastructure implementation. In the digital era, effective contract governance requires not only legal compliance but also technology-enabled mechanisms to ensure transparency, accountability, and balanced risk allocation. This study examines the legal protection and contract governance of Lump-Sum Design and Build agreements, focusing on how contract amendment mechanisms address the interests of contracting parties in the Jakarta–Cikampek II Elevated Toll Road Project. Using qualitative normative legal research with statute, conceptual, and case approaches, legal materials were analyzed through the lenses of contract governance, legal risk management, and digital transformation in project administration. The findings reveal that contract amendments function as critical governance instruments rather than mere administrative procedures. However, inconsistencies between contractual provisions and Indonesian construction service regulations regarding changes in work volume, technical specifications, and implementation requirements were identified. These gaps resulted in substantial contractual and financial impacts, totaling approximately Rp510.09 billion, due to unadjusted quantity variations. The study demonstrates that effective governance of Lump-Sum Design and Build contracts demands transparent, legally compliant, and digitally supported amendment mechanisms. Strengthening contract administration through digital tools, enhancing regulatory compliance, improving stakeholder coordination, and integrating technology-enabled risk management are essential to reduce legal uncertainty, mitigate financial risks, and support sustainable infrastructure delivery in strategic projects.]]>
