Strategic imperatives for the development of public administration in the context of digitalization: methodological and legal aspects

Purpose. To develop a dynamic mathematical model of the digital maturity index for public administration in Ukraine as a tool for quantitatively assessing the effectiveness of digital transformation in the context of European integration and martial law. Methodology. The comparative analysis method was applied to systematize conceptual approaches to digital transformation (human-centeredness, interoperability, transparency, data-driven management, security by design, inclusivity). Structural-functional analysis was used to examine the institutional architecture (the Ministry of Digital Transformation (MDT), the “Trembita” system, and the “Diia” portal), cybersecurity mechanisms, and the legal framework. The weighted aggregation method of five sub-indices was applied to construct a digital maturity index based on data from the MDT, CERT-UA, and Eurostat for 2019–2024. Findings. It has been established that the methodology of digital public administration in Ukraine is based on six key principles, which are implemented through a cyclical approach. The legal framework ensures the legal equivalence of electronic and paper documents. The digital maturity index rose from 0.34 in 2019 to 0.63 in 2024 and 0.72 in the first half of 2026. Trends in the components: the effectiveness of digital services rose from 0.31 to 0.80; the level of cybersecurity temporarily declined to 0.40 in 2022 before stabilizing at 0.53; interoperability increased from 0.28 to 0.78; citizen engagement – from 0.19 to 0.63; legal compliance – from 0.41 to 0.79. Systemic barriers were identified: inconsistencies in legislation, the need for harmonization with the GDPR and eIDAS, and insufficient implementation of business continuity plans. Originality. For the first time, a comprehensive combination of methodological, legal, and quantitative aspects of digital transformation has been proposed. An original dynamic model of the digital maturity index has been developed based on five weighted sub-indices. The four-level interoperability framework and the structure of legal compliance have been refined through the aggregation of harmonization with the GDPR, eIDAS, cybersecurity legislation, and administrative codes. Practical value. The results can be used by the Ministry of Digital Transformation of Ukraine and international partners to set priorities for digital transformation, assess the impact of cyber threats, and monitor progress in harmonization with the GDPR and eIDAS in the context of European integration.