Jerzy Adamczyk

-Collaborated with 27 developers to build an e-commerce site using PHP, MySQL, and JavaScript, launching in 3 months. -Designed a responsive email template with HTML5 and CSS3, boosting click-through rates by 78%. -Defined a technology roadmap with stakeholders, increasing team efficiency and project success by 40%. -Managed database schema design, improving data retrieval efficiency and scalability. -Optimized performance, reducing page load times by 40%. -Led debugging, decreasing error tickets by 60%.

Designed & implemented an interactive map for a real estate website, enabling 7,000 users to search by neighborhood and get real-time feedback. Developed front-end solutions using HTML, CSS, JavaScript, and jQuery, ensuring compatibility with 29 devices, including desktops and tablets. Improved performance by removing redundant scripts and styles, achieving a 69% reduction in load times Used Git for version control, ensuring smooth collaboration Implemented cross-browser fixes for consistent user experience

Collaborated with product teams to gather requirements and translate them into technical solutions, improving satisfaction. Built and maintained unit and integration tests with Jest and Selenium, increasing coverage and reducing bugs. Designed and implemented RESTful APIs to support mobile and web apps, reducing response time by 30%. Optimized SQL queries and database structures, cutting execution time by 50%. Developed scalable web apps with React, Node.js, and Python, improving performance for 100K+ users