About Kostiantyn
My strongest area is frontend engineering. component libraries/design systems, performance work, and clean UI architecture. Right after that comes full-stack: I'm comfortable going beyond the UI when needed, and I’m most effective working close to the backend - aligning on API contracts, data shapes, validation, and edge cases, then translating those decisions into a frontend that stays highly reliable as the project grows
I'm project-focused and driven to get things done. I value practical collaboration, honest feedback, and teams with clear communication - and with a roadmap, or the willingness to build one together
English
Fluent
Ukrainian
Native or bilingual
German
Basic
Remote only
Primarily works remotely
Experience
- Proxify (Client at platform)Senior Lead Frontend EngineerJuly 2023 - September 2025 (2 years and 2 months)Figma Vue.js• • Developed architecture for frontend applications within a large-scale Big Data API, ensuring scalability and performance• • Developed and maintained project-specific component library and design system• • Built high-performance frontends using Vue.js, Svelte, and TypeScript, improving application efficiency and maintainability• • Collaborated closely with backend developers and UX/UI designers to deliver high-quality code and optimized features through joint planning• • Established code review practices, maintaining consistency and code quality across the team• • Continuously stayed up-to-date with frontend technologies, adopting new tools and practices that enhanced team efficiency and product quality
- DNV GLSoftware Engineer (Senior Frontend Developer, Vue.JS / Svelte)August 2021 - January 2023 (1 year and 5 months)• • Contributed to development and maintenance of the micro-frontend orchestration shell within a well-architected infrastructure, delivering features across multiple environments using Vue.js, Svelte, and TypeScript• • Played a key role in implementing new micro-frontend applications, contributing to central component libraries and routing system that enabled faster development and consistent user experiences• • Enhanced and refactored components within the central library, ensuring consistency and prioritizing long-term maintainability through clean abstractions• • Implemented and maintained unit and integration tests, improving application stability and reducing time spent on bug fixes• • Collaborated with UX/UI designers, backend developers, and product managers in Agile environment• • Mentored colleagues in frontend development best practices and techniques• • Participated in code reviews, ensuring adherence to best practices and code quality standards
- Freelance, OutsourcingFull-Stack / Frontend DeveloperSeptember 2016 - September 2021 (5 years)• • Delivered diverse projects for clients: CMS-based websites, premium CMS templates/addons, frontend enhancements and optimizations, and custom web applications from scratch• • Built full-stack solutions using Vue.js, Laravel, Node.js, AdonisJs, and Express.js• • Developed and maintained component libraries and design systems in Vue.js for efficient UI development across projects• • Achieved measurable improvements in speed optimization, SEO, and quality audits, resulting in better site rankings and reduced load times• • Identified and resolved performance bottlenecks, security vulnerabilities, and code maintainability issues• • Worked with clients to gather requirements, provide estimates, and offer technical guidance• • Managed projects using Jira, Azure, and YouTrack, tracking progress and providing regular client updates
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Education
- Computer Engineering and Systems ProgrammingKhmelnytskyi National University2017Computer Engineering and Systems Programming