This article investigates the collaborative development and implementation of a modular, Lean-inspired professional development program for public servants in the Brazilian Ministry of Agriculture, integrating digital micro-credentials with participatory instructional design. Drawing on mixed-methods research, the study demonstrates that aligning Lean management tools with digital learning pathways enhances not only process optimization and operational efficiency, but also fosters a culture of continuous improvement and institutional learning within complex, decentralized public sector settings. Quantitative results reveal significant improvements in training completion rates, reduction of process errors, and increased engagement, while qualitative evidence highlights the value of co-constructed content, peer learning, and the democratization of access to professional development. The research also critically examines persistent barriers, such as lack of formal recognition for modular certification and digital inequalities, and contextualizes findings within global debates on educational innovation and sustainable governance. The Brazilian experience provides practical recommendations and theoretical insights for scholars, policymakers, and practitioners aiming to build resilient, adaptive, and citizen-centered public administration.