Hennadiy Kozlov

Senior Frontend Engineer

Kyiv, UA.

About

Highly accomplished Senior Frontend Engineer with 5 years of commercial experience specializing in React and TypeScript applications, adept at designing robust frontend architectures and optimizing performance for large-scale systems. Proven leader in full-stack development, consistently delivering high-impact enterprise solutions, enhancing user experiences, and mentoring high-performing engineering teams. Seeking to leverage advanced technical expertise and leadership skills to drive innovation in challenging software development environments.

Work

LIS

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Frontend Engineer

Kyiv, Kyiv, Ukraine

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Summary

Led the end-to-end frontend development of critical enterprise applications within the government and telecommunications sectors, driving architectural decisions and team mentorship.

Highlights

Spearheaded the frontend development of multiple complex enterprise applications from initial concept to deployment, significantly enhancing operational efficiency and user engagement.

Designed and implemented scalable frontend architectures, contributing to key technology decisions that improved system performance and maintainability across diverse projects.

Optimized rendering performance for large real-time geospatial datasets using virtualization and memory profiling techniques, achieving a 30% reduction in load times and smoother user interactions.

Conducted technical interviews, performed rigorous code reviews, and actively mentored junior developers, elevating team capabilities and ensuring adherence to best coding practices.

Developed comprehensive dashboards, reports, authentication systems, and WebSocket-based functionalities, providing robust tools for data visualization and real-time communication.

Knowledge Gate LTD

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Frontend / Full-stack Engineer

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Summary

Contributed to the full-stack development of a real-time dating platform, implementing key features and backend services to enhance user interaction and monetization.

Highlights

Developed and launched critical React and TypeScript features for a real-time chat application, improving user engagement and communication flow for thousands of users.

Implemented robust image and virtual gift messaging functionalities, increasing user interaction by an estimated 25% and diversifying platform offerings.

Built scalable backend chat functionality using NestJS and GraphQL, ensuring high performance and reliability for real-time messaging services.

Integrated secure payment functionality for virtual gifts and subscriptions, enabling seamless transactions and contributing directly to platform revenue generation.

w-Axis

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Frontend Engineer

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Summary

Delivered high-performance marketing websites and dynamic animations for a digital agency, focusing on user experience and site optimization.

Highlights

Developed and deployed a portfolio of marketing websites and high-conversion landing pages, enhancing client digital presence and lead generation efforts.

Created engaging, performant animations using GSAP and Three.js, significantly improving user experience and visual appeal across various web projects.

Optimized website loading speed and Core Web Vitals, achieving an average 20% improvement in performance metrics and enhancing SEO rankings for client sites.

Education

Kyiv Polytechnic Institute

Kyiv, Kyiv, Ukraine
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Bachelor Computer Engineering

Languages

Ukrainian

English

Skills

Frontend

React, TypeScript, JavaScript, Next.js.

State Management

Redux, React Query, Zustand, React Hook Form.

UI Libraries & Tools

Material UI, Tailwind CSS, GSAP, Three.js.

Backend

NestJS, Express.js, GraphQL, Apollo.

Other Technologies

OpenLayers, WebSockets, REST API, Git, Vite, Webpack, Frontend Architecture, Performance Optimization, Real-time Systems, Large-scale Data Visualization, Code Reviews, Technical Mentoring, Geospatial Applications.

Projects

Starfee — AI-powered SaaS Platform

Summary

Independently developed and launched a full-stack AI-powered SaaS platform from conceptualization to production, demonstrating comprehensive product development and entrepreneurial capabilities.