Sergey

Serhii Donchenko
Reykyavik, Iceland | [відкрити контакти](див. вище в блоці «контактна інформація») | Linkedin | Telegram
Software developer: with 5+ years of experience delivering high-quality web applications.
Skilled in JavaScript, TypeScript, React.js, Next.js, NodeJs, Express. Experienced in improving
performance, optimizing deployment pipelines, and delivering scalable solutions. Skilled in
UI/UX improvements and building large-scale, high-performance systems.

Experience

Software developer USA

NexaEvents - a leading event management company in Los Angeles May 2024 – Apr. 2025

Maintained and enhanced existing web applications, significantly improving performance
and scalability.
Designed and implemented front-end architecture independently, ensuring clean
structure and long-term maintainability.
Developed and deployed RESTful APIs with Node.js and integrated databases for
reliable data management.
Built and supported AWS-based infrastructure, leveraging cloud services for stability
and scalability.
Ukraine
Front-end developer
Sep. 2021 – Dec. 2023
HYS Enterprise - leading IT outsourcing company in Ukraine
• Worked on one of the largest travel domains in the Netherlands, contributing to a full
redesign and modernization of the platform.
• Migrated legacy codebase to modern technologies, ensuring long-term maintainability
and scalability.
• Collaborated within a large Agile team, following Scrum practices and delivering features
iteratively.
• Improved website performance and user experience, optimizing frontend workflows and
reducing load times.
• Participated in code reviews and knowledge sharing sessions, raising overall code
quality and team expertise.
• Contributed to side projects with Angular and Angular 2+, expanding frontend expertise
beyond React.
Ukraine
Front-end developer Oct. 2020 – Sep. 2021
Atlanta – a leading real estate and property rental company in Ukraine
• Contributed to the company’s website development, adding new features and supporting
functionality.
• Gained hands-on experience with modern front-end technologies while contributing to
production features.

Ukraine
Web developer
Nov. 2019 – Jun. 2020
Westelecom – one of the top 5 internet service providers in Odesa, Ukraine

• Fully developed and styled the company’s website from scratch.
• Explored backend development, gaining initial experience with PHP and Yii2 framework.
Experience

Languages: JavaScript, TypeScript, HTML, CSS.
Tools: Webpack, AWS, Docker, Axios, Storybook, Jest, Cypress, Graphql
Frameworks/Libraries: React, Next.js, Redux, Zustand, GraphQL, Angular, Angular 2+, Node.js,
Express, MongoDB, Stripe, React-query, MUI, Firebase, jQuery

Concepts:
Performance Optimization, UI/UX Design, A/B Testing, CI/CD, SPA, PWA, RESTful API,
Agile/Scrum, SEO optimization, API Development, Cloud Infrastructure (AWS).

Language Skills:
English — upper-intermediate (fluent in professional communication);
Ukrainian — native.

Education

Computer Engineering, International Humanities University
Ukraine, Odesa
Master of Science in Computer Science
2012-2018

Courses

NodeJs course 2025

JavaScript course
2021