
Jakub Korytko engineered robust authentication and multifactor security features across Expensify/App and related repositories, focusing on biometric groundwork, secure storage, and cross-platform consistency. He integrated biometric authentication using Swift and Kotlin, unified SecureStore feedback models, and enhanced authentication flows to support scalable MFA with ED25519 cryptography. Jakub improved user experience by refining UI components, adding localization support, and addressing device compatibility. His work included strengthening CI/CD pipelines with Jest and GitHub Actions, stabilizing offline authentication, and implementing custom React hooks for state management. These contributions demonstrate depth in mobile security, frontend engineering, and full stack development within production environments.

February 2026: Delivered targeted frontend improvements and localization for Expensify-App, while hardening offline/auth flows and PR workflows. Key outcomes include UI polish on the Prompt Page, a new Unsupported Device screen, Parrot language support, and significant bug fixes to PR comments/CI, offline authentication, and code quality that reduce user friction and improve reliability across MFA, registration, and protected routes. These efforts demonstrate strong frontend engineering, user-centric UX, and robust localization capabilities with measurable business impact in onboarding, device compatibility, and developer workflow.
February 2026: Delivered targeted frontend improvements and localization for Expensify-App, while hardening offline/auth flows and PR workflows. Key outcomes include UI polish on the Prompt Page, a new Unsupported Device screen, Parrot language support, and significant bug fixes to PR comments/CI, offline authentication, and code quality that reduce user friction and improve reliability across MFA, registration, and protected routes. These efforts demonstrate strong frontend engineering, user-centric UX, and robust localization capabilities with measurable business impact in onboarding, device compatibility, and developer workflow.
January 2026 focused on hardening security, reliability, and user experience for MFA-enabled flows across Expensify apps, with parallel work on UI, cryptography, context/state management, and test infrastructure. The efforts elevated security posture, reduced risk, and strengthened CI feedback loops, while delivering scalable MFA capabilities and improved user authentication UX.
January 2026 focused on hardening security, reliability, and user experience for MFA-enabled flows across Expensify apps, with parallel work on UI, cryptography, context/state management, and test infrastructure. The efforts elevated security posture, reduced risk, and strengthened CI feedback loops, while delivering scalable MFA capabilities and improved user authentication UX.
September 2025 focused on strengthening authentication security and cross‑platform consistency by delivering biometric groundwork and SecureStore enhancements across two related Expensify repositories. The work sets the foundation for biometric login, secure data handling, and improved UX around secure storage prompts, with targeted iOS/Android considerations and patches to underlying platform integrations.
September 2025 focused on strengthening authentication security and cross‑platform consistency by delivering biometric groundwork and SecureStore enhancements across two related Expensify repositories. The work sets the foundation for biometric login, secure data handling, and improved UX around secure storage prompts, with targeted iOS/Android considerations and patches to underlying platform integrations.
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