Senior Fullstack Engineer

Role details

ABOUT THE ROLE This is a senior individual contributor role on a small, fast-moving engineering team building an AI-powered phone assistant for European SMEs. You'll own features end-to-end — from discovery and architecture through to release — and your work will have a direct, measurable impact on thousands of business customers. WHAT YOU'LL DO - Take full ownership of product features from initial idea and prototype through architecture, implementation, and release. - Engage regularly with customers, partners, and Sales to surface real pain points and turn them into product improvements. - Run lightweight product discovery by forming hypotheses and validating them with quick experiments before building large systems. - Instrument your work and gather the metrics needed to support data-driven decisions. - Build pragmatic, scalable software that balances immediate customer value with long-term maintainability. - Communicate asynchronously and prioritise shipping over excessive meetings. - Act with radical ownership — push initiatives forward without waiting for direction. WHAT WE'RE LOOKING FOR - 5+ years of experience as a fullstack engineer with end-to-end delivery responsibility for customer-facing web applications. - Strong hands-on experience with Node.js, TypeScript, NestJS, and React. - Native-level German proficiency — essential for supporting a German-language AI product. - Fluent English for team and internal communication. - Product mindset: you measure success by customer value, not lines of code. - Proven experience with product discovery, hypothesis-driven experimentation, and metrics-based decision making. - Track record of collaborating directly with customers, partners, or sales teams to define and validate product value. - Strong CS fundamentals and sound judgment when trading off speed, quality, and effort. - Experience integrating LLMs (e.g. OpenAI APIs) into production applications is a significant plus. - Familiarity with GDPR or EU AI Act considerations for AI services is a plus. - Experience deploying AI-enabled services on cloud infrastructure in Europe (e.g. Azure) is a plus. - Prior experience in a high-growth startup environment is a plus. COMPENSATION & BENEFITS Salary range: €80,000 – €120,000 per year. Visa sponsorship is not available. LOCATION Fully remote, with a preference for candidates based in Germany or Austria (CET timezone overlap required). An office in Vienna, Austria is available for those who prefer it.