Serafym

Serafym Starobrianskyi
FRONTEND DEVELOPER
Košice, Slovakia | [відкрити контакти](див. вище в блоці «контактна інформація»)
[відкрити контакти](див. вище в блоці «контактна інформація»)
github.com/SerafymStarobrianskyi

PROFESSIONAL SUMMARY
Frontend Developer with commercial experience building React and TypeScript features for WinWin.travel, a
travel booking platform. Hands-on experience with responsive interfaces, client-side data caching, server-side
rendering, and web performance. Computer Science student at the Technical University of Košice.

PROFESSIONAL EXPERIENCE
Frontend Developer | WinWin.travel (WWT)
May 2026 - Present
• Develop and maintain React and TypeScript features for a travel booking platform, including search, booking
flows, authentication forms, and responsive page layouts.
• Implemented frontend support for multiple domains, adapting server-side rendering, canonical URLs, sitemaps,
and authentication redirects to the active domain.
• Reduced render-blocking CSS by inlining critical styles during server-side rendering and deferring the main
stylesheet.
• Resolved caching and navigation issues with TanStack Query and React Router, fixing comparison-page refresh
errors and incorrect offer-tab routing.
• Extended configurable landing pages with custom HTML content and automatic iframe resizing to support
responsive layouts across screen sizes.

TECHNICAL SKILLS
Languages & frameworks: JavaScript, TypeScript, React, React Router
UI development: HTML5, CSS3, SCSS, Tailwind CSS, responsive design, accessibility
Data fetching & caching: TanStack Query (React Query), REST APIs, query persistence
Rendering & performance: Server-side rendering (SSR), critical CSS, stylesheet loading
Testing & quality: Vitest, Testing Library, ESLint, regression testing, code review
Development tools: Git, GitHub, Figma, Linux

SELECTED PROJECTS
AI Chat App | React | GitHub | Live demo
Built a chat interface with streamed AI responses and interactive conversations.
Nexora | React, TypeScript, Node.js | GitHub | Live demo
Built a workspace-based notes app with a Markdown editor, folders, internal links, and a knowledge graph.
Implemented an Express/PostgreSQL backend with JWT authentication and protected routes.

EDUCATION & TRAINING
Technical University of Košice (TUKE)
BSc in Computer Science | 2024 - Present
SoftServe IT Academy | Fullstack JavaScript Developer Program, three modules completed
Hashtag Academy | JavaScript Course