Karol Piotrowski

Led the design and development of responsive corporate websites using HTML5, CSS3, JavaScript, and WordPress. architected scalable front-end systems with reusable components, translated blockchain and regulatory service offerings into structured, accessible content, and implemented advanced SEO and performance strategies that increased organic traffic by about 45%. Implemented high-performance forms with robust validation to improve lead capture. Optimized performance with lazy loading, caching, and Core Web Vitals improvements, achieving sub-two-second load times across major browsers and devices. Collaborated with stakeholders to align messaging with regulatory standards and developed custom WordPress themes and plugins for dynamic content delivery. Led usability testing to enhance navigation and accessibility, established documentation frameworks for maintenance and future feature integration, and integrated analytics to support data-driven UX and SEO optimization. Drove cross-funct

Architected and delivered highly interactive React-based web applications, leveraging JavaScript, HTML5, and CSS3 to improve user engagement across multiple digital education and community platforms. Engineered interactive modules using Canvas API and WebGL, implemented responsive design with React and TypeScript, and collaborated with product designers to translate educational objectives into intuitive interfaces. Developed REST APIs with Node.js/Express, optimized performance, accessibility, and CI/CD pipelines; mentored junior developers.

Delivered end-to-end PayHip front-end implementations across multi-page digital product sites, translating provided mockups into clean, conversion-optimized HTML, CSS, and JavaScript with zero backend dependencies. Implemented 12–14 page front-end scopes with consistent visual systems, ensuring typography, spacing, color usage, and component behavior remained uniform across all customer touchpoints. Customized PayHip product pages using platform-supported markup and styling techniques, enhancing perceived product value while maintaining full compatibility with hosted checkout flows. Applied responsive design principles to guarantee reliable rendering across desktop, tablet, and mobile breakpoints, improving engagement metrics and reducing bounce rates. Integrated light JavaScript logic for UI interactions, dynamic content toggles, and usability enhancements without introducing unnecessary complexity or performance overhead. Optimized front-end assets and stylesheets to improve load t