Application Developer (Web Technologies) (f/m/d)

📍 Vienna, Austria — or fully remote within ±2 hours CET

💼 Full-time permanent contract (possible in Austria and Germany) or long-term Freelance (within ±2h CET)

What You Will Do

• Build and evolve a high-performance, browser-based core application used in real POS and payment environments
• Develop with pure JavaScript — no frameworks, maximum control, full understanding of browser internals
• Work closely with system architects, product managers and a hands-on technical leadership group
• Contribute to an ongoing re-engineering initiative (microservices on Node.js, with Go planned down the line)
• Participate in architecture discussions, code reviews and deep-dive technical workshops
• Drive performance, reliability and maintainability across the application
• Grow into architecture or technical leadership if this aligns with your ambitions

What You Bring

• Strong, in-depth experience with vanilla JavaScript and native browser APIs (DOM, Fetch, WebSocket, Storage, etc.)
• The ability to build performant applications without relying on frameworks
• A clean, structured coding style and a strong sense of software quality
• Experience with Git workflows, testing methodologies and collaborative review processes
• A proactive, ownership-driven mindset — you like to take responsibility, not wait for instructions

Nice to have

• Experience with Node.js, Go or C (microservices, embedded systems, device-level development)
• Exposure to POS, payment, IoT or hardware-connected software
• Understanding of binary or non-JSON communication formats
• Interest in re-engineering, system design, scalability and distributed architectures

Work model

• Remote-first within ±2h CET
• Optional office days in Vienna (not required)
• Two on-site team weeks per year in Vienna — travel and accommodation covered
• Full-time employment possible for candidates in Austria and Germany
• Long-term freelance collaboration possible from any country within ±2h CET

Why this role is exciting

• You work on engineering challenges that very few browser-based systems face
• You help shape a platform that interacts with real hardware and processes real transactions
• You join a fast-moving company where decisions are made quickly and engineers have influence
• You become part of a culture that values clarity, trust, autonomy and people who genuinely care about their craft
• If you want to work on technology that combines browser engineering, device connectivity and real-world impact — this is where it all comes together