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Senior Full-Stack JavaScript Developer with 5+ years of experience in frontend and backend development. Skilled in React, React Native, Next.js, and Node.js, building scalable, high-performance web and mobile applications. Committed to delivering top-quality results on time, continuously improving skills, and staying current with modern technologies. Enthusiastic about collaboration, solving challenges, and creating efficient, engaging digital experiences.…Senior Full-Stack JavaScript Developer with 5+ years of experience in frontend and backend development. Skilled in React, React Native, Next.js, and Node.js, building scalable, high-performance web and mobile applications. Committed to delivering top-quality results on time, continuously improving skills, and staying current with modern technologies. Enthusiastic about collaboration, solving challenges, and creating efficient, engaging digital experiences.

Serhii Matiichyn

Full Stack Developer, Front-End Developer, Web Developer, +3

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Senior Full-Stack JavaScript Developer with 5+ years of experience in frontend and backend development. Skilled in React, React Native, Next.js, and Node.js, building scalable, high-performance web and mobile applications. Committed to delivering top-quality results on time, continuously improving skills, and staying current with modern technologies. Enthusiastic about collaboration, solving challenges, and creating efficient, engaging digital experiences.…Senior Full-Stack JavaScript Developer with 5+ years of experience in frontend and backend development. Skilled in React, React Native, Next.js, and Node.js, building scalable, high-performance web and mobile applications. Committed to delivering top-quality results on time, continuously improving skills, and staying current with modern technologies. Enthusiastic about collaboration, solving challenges, and creating efficient, engaging digital experiences.

Available to hire

Senior Full-Stack JavaScript Developer with 5+ years of
experience in frontend and backend development.
Skilled in React, React Native, Next.js, and Node.js,
building scalable, high-performance web and mobile
applications.
Committed to delivering top-quality results on time,
continuously improving skills, and staying current with
modern technologies. Enthusiastic about collaboration,
solving challenges, and creating efficient, engaging
digital experiences.

Skills

Experience Level

Expert

Expert

Expert

Expert

Language

Ukrainian

Fluent

English

Advanced

Work Experience

Full-Stack JavaScript Developer at GearHeart

June 20, 2020 - May 20, 2021

Developed front-end and back-end features using React, Redux, RESTful APIs, GraphQL, and Web Sockets; implemented real-time updates; leveraged Zustand for state management; built responsive UI; collaborated with cross-functional teams.

Full-Stack JavaScript Developer at SoftServe

January 20, 2023 - September 20, 2024

Designed and built a React-based health care management platform for booking appointments, viewing records, and patient–doctor communication. Used Redux for state management, RESTful APIs, and JWT/OAuth2 for authentication; implemented lazy loading and CI/CD via Netlify.

Front-End Developer at Gear Heart

June 20, 2020 - May 20, 2021

Implemented responsive UI components and features for web apps using React and JavaScript; collaborated with design and backend teams to deliver polished user interfaces.

JavaScript Developer at Pyrotech

July 1, 2021 - December 1, 2022

Built front-end for client projects using React, TypeScript, Redux Toolkit, and RESTful APIs; implemented authentication flows with OAuth/JWT; integrated GraphQL, RESTful data fetching, and testing with Jest; deployed on Netlify.

Full-Stack JavaScript Developer at EvoTec

January 1, 2023 - October 1, 2025

Designed and built project management web platform with real-time collaboration; leveraged React, Next.js, TypeScript, Node.js, GraphQL; state management with Redux Toolkit/React Query; JWT/OAuth2 authentication; implemented RESTful APIs, Web Sockets, Tailwind; deployed with Vercel; ensured performance and accessibility.