Anna Kellerstein
Software Engineer II at Microsoft
Prague, Prague, Czechia
Summary
🤩
Rockstar🎓
Top SchoolAnna Kellerstein is a Software Engineer II based in Prague with nine years of experience building responsive front-end applications and UI libraries. At Microsoft she contributes to Fluent UI, improving components, accessibility, styling, and test coverage for a widely used open-source design system. Her background includes several Angular-focused frontend roles where she delivered production-ready features and polished UX across startups and agencies. With a master's in Algebra and Number Theory, she brings strong analytical rigor to debugging complex UI interactions and edge-case styling. Colleagues rely on her to translate design requirements into robust, testable components while tightening documentation and visual tests. Notably, she pairs production engineering with contributions that improve developer experience in a major Microsoft UI project.
9 years of coding experience
4 years of employment as a software developer
Master's degree, Algebra and Number Theory, Master's degree, Algebra and Number Theory at Taras Shevchenko National University of Kyiv
Ukrainian, English, Czech
Github Skills (15)
css10
javascript10
react-components10
component-kit10
fluentd10
react10
react-component10
ui-components10
accessibility9
typescripts8
typescript8
testing8
typescript-types8
github7
documentation7
Programming languages (1)
Github contributions (5)
microsoft/fluentui
Aug 2021 - May 2022
Fluent UI web represents a collection of utilities, React components, and web components for building web applications.
Role in this project:
Front-end Developer
Front-end DeveloperContributions:9 reviews, 12 commits, 17 PRs in 8 months
Contributions summary:Anna primarily contributed to the implementation and enhancement of UI components within the Fluent UI web library. Their work involved extending styling properties, modifying focus styles, and fixing issues related to dropdown and dialog components. The commits also include updates to documentation and screener tests, ensuring proper functionality and responsiveness. Additionally, the user addressed issues such as button icon styles and avatar font weights.
web-componentsreact-component-libraryreact-componentsmicrosoftui-components
annabratseiko/fluentui
Aug 2021 - Jan 2024
Fluent UI web represents a collection of utilities, React components, and web components for building web applications.
Contributions:66 pushes, 14 branches in 2 years 5 months
reactweb-applicationslitweb-uiweb-components
Find and Hire Top DevelopersWe’ve analyzed the programming source code of over 60 million software developers on GitHub and scored them by 50,000 skills. Sign-up on Prog,AI to search for software developers.