Kris Rzepka
Full Stack Developer
+ Back-End / + DevOps
About
Hello! I'm a Developer based in Bristol, UK, with a passion for building scalable, high-performance web applications.
I specialize in JavaScript, React.js, Node.js, and AWS, and I thrive on solving complex technical challenges while delivering clean, efficient code. With a strong foundation in both front-end and back-end development, I enjoy creating seamless user experiences and robust systems. I'm skilled in agile methodologies, cloud computing, and RESTful APIs, and I'm always eager to learn and adapt to new technologies.
When I'm not coding, you'll find me exploring the outdoors, staying active through powerlifting and running, or diving into a good book. I'm always open to new opportunities, collaborations, or just a friendly chat—feel free to reach out!
Skills
Portfolio
Gazetteer API Application
An interactive web application that allows users to explore global geographical data. It provides information on country borders, weather, Wikipedia entries, and local time. The app integrates multiple APIs and features an intuitive map interface with dynamic markers and overlays.?
Company Directory CRUD App
Developed a modular web-based system to manage personnel, departments, and office locations via a tabbed interface.
Backend implemented in PHP with MySQL database integration, handling all CRUD operations through RESTful logic.
Frontend built with JavaScript, Bootstrap, and jQuery, delivering a responsive UI and smooth user interactions. AJAX is used for asynchronous communication with the server, enabling real-time updates without page reloads.
Lottery Prediction System
A Python 3 back-end system that leverages AI and statistical modeling to predict lottery numbers with high diversity and uniqueness. It analyzes historical data (1996–2025) and applies:
✅ Machine Learning (AI) – GRU for sequence prediction and XGBoost for trend analysis.
✅ Statistical Scoring – Weighted frequency analysis with recency and "cold number" boosts.
✅ Combinatorial Analysis – Identifies frequent numbers and pairs while ensuring diverse predictions.
✅ Data Processing – Uses pandas and NumPy for efficient handling of large datasets.
Built with TensorFlow, scikit-learn, and optimized for macOS with 16GB RAM, this system generates 5 unique sets of lottery numbers, ideal for API integration or advanced analytics. 🚀
Pay Pal Web Clone Engineered a PayPal web clone with secure payment processing and user authentication. Utilized React and Redux for a responsive, state-managed frontend. Implemented backend services with Node.js and Express, ensuring robust transaction management and API integration. Employed MongoDB for scalable data storage. Focused on security best practices, including encryption and secure session handling.
One page portfolio Designed and developed a sleek, one-page portfolio showcasing projects, skills, and experience. Utilized HTML, CSS, and JavaScript for a clean, responsive design. Implemented smooth scrolling and interactive elements with React. Focused on SEO optimization and performance for a fast, engaging user experience.
Curriculum Vitae
Discover my journey as a Full Stack Developer with expertise in React, Node.js, AWS, and more. From building scalable APIs to deploying cloud-based solutions, my CV showcases my passion for creating impactful applications.
Curriculum Vitae
Summary
Experienced Full Stack Developer with expertise in JavaScript, React.js, Node.js, and AWS, dedicated to building scalable, high-performance web applications. A reliable and detail-oriented professional, I thrive in agile environments, delivering clean, efficient code and exceptional user experiences. With strong problem-solving skills and a commitment to continuous learning, I excel at collaborating in teams and delivering high-quality products to clients.
Education
03/2024-03/2025 | IT Carrier switch
Completed an intensive Full Stack Development Training Program, gaining hands-on experience in front-end and back-end development. Mastered JavaScript, React.js, Node.js, PostgreSQL, and AWS, while working on real-world projects to build a strong portfolio.
### **Certifications**
✔ **Full Stack Engineer**
✔ **JavaScript**
✔ **jQuery**
✔ **Python 3**
✔ **C#**
✔ **PHP**
✔ **Bootstrap**
✔ **AWS Cloud Practitioner** – In Progress
This training has equipped me with a strong analytical mindset, the ability to write clean and efficient code, and a passion for solving complex problems through software development.
2000-2005 | IT - Focused – Technical College (Equivalent to UK A-Levels)
Computer science
Languages
Polish (Native Language)
English (Fluent)
Experience
04/2025 | Gazetteer API Project
@ remote
Developed an interactive mapping application using Leaflet.js and multiple APIs (GeoNames, OpenWeather, Wikipedia).
Gained hands-on experience with AJAX, PHP, and JavaScript for API integration.
Improved UI with Bootstrap and enhanced user interactions with Leaflet plugins.
Deployed the project using Docker and Render.
03/2025 | Company Director API App
@ remote
Developed a dynamic CRUD web application for managing employees, departments, and office locations within a company.
Built with PHP and MySQL on the backend, and JavaScript, Bootstrap, and jQuery on the frontend.
Implemented AJAX for seamless server communication without reloading pages.
Designed modals and tabs using Bootstrap to enhance user interaction and maintain clean UI/UX.
Gained experience with structured full-stack development and version control.
11/2024 | Lottery Prediction System
@ remote
A Python 3 back-end system that leverages AI and statistical modeling to predict lottery numbers.
It analyzes historical data (1996–2025) and applies:
✅ Machine Learning (AI) – GRU for sequence prediction and XGBoost for trend analysis.
✅ Statistical Scoring – Weighted frequency analysis with recency and "cold number" boosts.
✅ Combinatorial Analysis – Identifies frequent numbers and pairs while ensuring diverse predictions.
✅ Data Processing – Uses pandas and NumPy for efficient handling of large datasets.
Built with TensorFlow and scikit-learn, this system generates 5 unique sets of lottery numbers, optimized for macOS with 16GB RAM, making it ideal for API integration or advanced analytics. 🚀
05/2024 | PayPal Clone Website
@ remote
Developed a single-page front-end application based on a professional FIGMA design.
04/2024 | One page portfolio
@ remote
Created a sleek, responsive one-page portfolio using HTML, CSS, JavaScript, and React, showcasing projects, skills, and experience with smooth navigation and dynamic content integration.
Let's talk about your project and how I can help you.
© Kris Rzepka,