Developed an internationalization enhancement for the actualbudget/actual repository, focusing on user language preference handling and locale fallback. Leveraging TypeScript and front end development skills, the work iterated through browser-provided language preferences to select the first supported locale, defaulting to English when necessary. The implementation included robust region locale checks and comprehensive unit testing to ensure reliability and alignment with existing test suites. Release notes and documentation were updated to reflect these changes. This feature improved multilingual user experience, reduced locale-related errors, and positioned the application for broader market reach by supporting expansion into additional languages and regions.