You’re an engineer who wants to build software that actually matters — not another layer of abstraction, but real technology used in real environments.

You want to work on a product where your code interacts directly with devices, processes high-volume transactions, and still runs entirely in the browser.

And you’re looking for a place where strong engineering principles, autonomy and fast decision cycles are part of the daily routine — not just buzzwords.

Our client is a fast-growing European SaaS provider in the payment and POS technology space, headquartered in Vienna, Austria. Its browser-based platform powers real-time payment flows, device interactions and business operations for thousands of merchants.

To strengthen the core team, we are looking for an experienced developer who thrives in an environment where people move fast, own their work and shape technology that has real-world impact.

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