- Tech Lead and Fullstack Software Engineer
Hi, I’m Julius Seltenheim — Engineering Lead, Architect, and Senior Fullstack Developer with over a decade of experience turning complex ideas into elegant, scalable software. From cloud-native systems and microservices to high-performance frontends, I bring both strategic vision and hands-on expertise to every project.
Whether you’re a startup building from scratch or an enterprise optimizing mission-critical systems, I help teams deliver with confidence, clarity, and speed. With a strong foundation in Java, Python, and TypeScript, I’ve led engineering teams across industries — from public sector apps to media platforms and SaaS tools — always focusing on clean architecture, agile processes, and long-term maintainability.
Let’s build something great together.
Testimonials
It was an absolute pleasure working with Julius over the past four months. He joined our cross-functional team, collaborating with our partner in the public sector to build a React and Python-based web application. Julius seamlessly stepped in to cover for a colleague on parental leave and quickly became an integral part of the team.
Julius took on the role of leading the development team, excelling in areas such as full-stack development, stakeholder communication, and feature preparation. His energy, initiative, and expertise were invaluable, driving significant improvements to the project's structure and code quality.
The team’s feedback was overwhelmingly positive, and I wouldn’t hesitate to work with him again in the future.
Thank you, Julius, for your outstanding contributions!
Julius worked with us on a project to improve our video rendering system architecture. He led the efforts as the technical lead of a small team of developers. Over the span of 4 months he was able to identify issues and bottlenecks of the previous system, design an new architecture, plan the project and implement many crucial parts of the new architecture.
Through his fullstack expertise he was able to both direct and execute the backend efforts as well as implement the frontend tasks himself, as he was the only developer on the team with relevant frontend knowledge.
It was a pleasure working with him and seeing the project coming to live in time and budget. The feedback from his team was extremely positive and his work will have a lasting effect on our product.
Julius, thank you so much, we hope to work again with you soon.