Founding Product Engineer

Join fonio.ai as a Founding Product Engineer to take end-to-end ownership of product features—from idea and prototype to production—helping scale a German-focused AI phone assistant used by customers across Europe. You’ll work on the Engineering team with strong product and customer focus, validating ideas quickly and shipping pragmatic software that delivers measurable value.

What you'll do

• Own features end-to-end from hypothesis to production for products used by thousands of companies in Europe.
• Lead product discovery by developing and testing hypotheses through rapid experiments.
• Maintain close, recurring contact with customers, partners, and Sales to surface real pain points.
• Design and implement tracking to gather the metrics needed for data-driven decisions.
• Build software across the stack, driving architecture choices and implementation through release.
• Prioritize pragmatic solutions that balance immediate validation with long-term scalability.
• Drive experiments and lightweight prototypes before investing in large-scale builds.
• Take radical ownership of initiatives and move them forward without waiting for sign-offs.

What fonio.ai is looking for

• Full-time, remote-first engineer working with overlap in CET and access to optional Vienna office.
• Role in the Engineering department as a Product Engineer with significant ownership responsibilities.
• Strong experience with Node.js, TypeScript, NestJS, and React.
• Experience integrating or working with large language models is a strong advantage.
• Deep product mindset with responsibility beyond coding and focus on customer value.
• Native-level German proficiency to support a German-language AI phone assistant.
• Comfortable extracting and owning relevant metrics to argue and iterate based on data.
• Pragmatic, experiment-driven approach to validating and shipping features.
• Competitive compensation (€80K–€120K) and equity as part of a high-growth environment.