Dominik H.

CEO & Co-founder

Quizonator • Freelance

Nov 2024 - Present • 1 yr 11 mos

I co-founded and run Quizonator, an AI study assistant that brings a Chrome extension, Android and iOS apps and a web dashboard into one product. More than 80,000 accounts have been created across the product. Quizonator is my own product, and I lead both its direction and development. My work covers the journey from deciding what users need to building the experience they interact with. I develop the frontend and backend, connect the different parts of the product and work on the features that turn a study idea into a practical tool. The service includes Firebase and Node.js on the backend, Stripe payments and releases for the mobile app stores. Running the product gives me hands-on experience with the work beyond a single screen: making browser, web and mobile experiences fit together, handling saved data, connecting payments and preparing releases. It also means thinking about what belongs in a focused first version and what should be planned as a later step. For clients, that experience is useful when an idea needs to become a clear, manageable project. Whether the starting point is a Chrome extension, a small web app or a simple mobile app, I can help define the essential user journey and the scope before development starts.

Full-stack Developer

Hotels Audit • Part time

Dec 2023 - Present • 2 yrs 10 mos

I build and maintain a custom hotel audit system that helps auditors work with checklists, photos and reports in one connected workflow. The system includes a web application, an offline-ready PWA for auditors and an iOS app. The work focuses on the practical details of an audit: recording checklist results, attaching photos, keeping audit data organized, supporting real-time collaboration and producing PDF reports. The offline-ready experience is designed around situations where auditors need to keep working without a reliable connection. The web and mobile parts serve the same underlying audit process. My responsibilities include developing and maintaining these application features and the connections between them. I work with NestJS and React, use WebSockets for real-time collaboration and Cloudinary for images. These choices support the experience, while the aim remains clear: give users a useful way to carry out and document their work. This project gives me hands-on experience with applications built around a real business process. For a client planning an internal tool, a checklist app or a reporting workflow, I understand why the screens, data, photo handling and final output need to fit together. I use that experience to help turn a broad requirement into a focused scope that can be discussed and built.

Freelance Developer

Freelance • Freelance

Jan 2022 - Present • 4 yrs 9 mos

I build Chrome extensions, focused web applications, mobile apps and automation scripts for clients. My work is centered on practical tools: helping someone complete a task, turn an idea into a first useful version or reduce repetitive work. Depending on the project, the starting point can be a small fix in an existing app, a new feature in a browser extension, a few screens with saved data or a script for a clearly defined workflow. I discuss the expected result and the boundaries of the work before development so the project has a clear purpose. Recent work includes Stajnia Wiedzy, a learning platform for the Polish market. Alongside client projects, I bring experience from building my own product, Quizonator, and developing a custom hotel audit system. That mix covers browser tools, web dashboards and mobile experiences used for different everyday needs. I communicate in plain language and ask for the information that helps make a project concrete: who will use the tool, what they need to do, which steps currently cause friction and what a successful result should look like. Screenshots, sketches and sample inputs are welcome. I reply the same day and help clients choose a package or define a custom scope for a larger project.