During a two-month period, Hoa Dat delivered Vietnamese localization for the KOReader User Guide in the koreader/koreaderhub.io.git repository, progressing from an initial 10% to 97% translation coverage. Hoa established a repeatable localization workflow using PO files and Weblate, ensuring accurate integration and change tracking. The work focused on content management, internationalization, and translation, surfacing Vietnamese content directly in the documentation to improve accessibility for Vietnamese-speaking users. By updating language identifiers and refining translated strings, Hoa supported KOReader’s internationalization roadmap and expanded its market reach, demonstrating depth in localization engineering and a methodical approach to multilingual content delivery.