Den Khmura

Senior Frontend & Mobile Developer with 5+ years of experience building scalable web and mobile applications using React, Next.js, and React Native. I specialize in delivering high-performance, production-ready products with a strong focus on clean architecture, scalability, and user experience. I have experience working across startup and product-driven environments, where I contributed to building AI-powered platforms, cross-platform mobile applications, and high-traffic web systems. My work spans from designing system architecture to deploying applications and optimizing them for performance and SEO. I’ve independently developed and shipped mobile applications to both the App Store and Google Play, as well as built and scaled complex web platforms using SSR/SSG approaches in Next.js. I’m comfortable working closely with product, design, and backend teams in agile environments, ensuring smooth collaboration and fast delivery. Core areas of expertise: • React, Next.js, React Native • Performance optimization (Core Web Vitals, code splitting, lazy loading) • Scalable frontend architecture and reusable component systems • API integration (REST, third-party services, AI APIs) • State management and complex data flows • Deployment and production-ready delivery • Cross-functional collaboration in agile teams I enjoy working on challenging products where performance, scalability, and user experience matter, and where I can contribute not only as a developer but as a problem solver