Aligning public finance with green economy goals is hindered by a gap between strategic declarations and budgetary realities, which is rooted in systemic information and coordination failures. Although performance-based budgeting is a recognized reform, it is insufficient without a deep digital transformation, which creates a research gap regarding the technological prerequisites for its success. This study analyses the institutional architecture for green Public Financial Management that is being formed in Uzbekistan during the pilot implementation phase of performance-based budgeting. The analysis is based on a corpus of official documents, ranging from national strategies to operational acts that define the performance-based budgeting methodology and the national Green Taxonomy. The findings show that Uzbekistan is laying the foundations for a data-driven system. Linking national strategy to the budget through performance-based budgeting and standardizing green activities via the Taxonomy create a machine-readable policy architecture to mitigate greenwashing risks. However, inter-departmental digital fragmentation remains a critical challenge. The research concludes that overcoming these information failures requires a genuine digital transformation, which entails creating a holistic digital ecosystem for green finance that utilizes advanced technologies and fosters a data-driven governance culture. The study’s findings offer strategic guidance for decision-makers. As the work is a normative case study, it focuses on system design; future research should assess the practical impact on budgetary and environmental outcomes.