Senior Fullstack Engineer

About the Role

This is a Senior Fullstack Engineer role at a fast-growing European AI voice assistant company serving small and medium-sized businesses. You will take end-to-end ownership of product features, from early discovery and prototyping through to architecture, implementation, and release, in a remote-first environment with a strong product and customer focus.

What You'll Do

• Own features across the full product lifecycle: idea, prototype, architecture, implementation, and release.
• Engage regularly with customers, partners, and Sales to surface real pain points and define value.
• Run product discovery by forming hypotheses and validating them quickly through lightweight experiments.
• Instrument your areas of ownership and gather metrics to support data-driven decisions.
• Build pragmatic, scalable software that balances immediate value with long-term maintainability.
• Communicate asynchronously and prioritize shipping over excessive meetings.
• Act with radical ownership and drive initiatives forward independently.

What We're Looking For

• 5+ years of experience in fullstack engineering with end-to-end delivery responsibility for customer-facing web applications.
• Strong hands-on experience with Node.js, TypeScript, NestJS, and React; substantial frontend and backend coverage is required.
• Experience with product discovery: forming hypotheses and validating them quickly through experiments.
• Comfortable identifying, collecting, and using metrics to inform product decisions.
• Skilled at collaborating directly with customers and partners to extract actionable insights.
• Native-level German proficiency is required; fluent English is also expected for team communication.
• Experience integrating LLMs (such as OpenAI) into production software is a strong plus.
• Familiarity with GDPR and EU AI Act considerations for AI-powered services is a plus.
• Experience working in a high-growth startup environment is a plus.
• Strong CS fundamentals and sound judgment around effort, quality, and speed trade-offs.

Compensation & Benefits

Salary range

80,000 to 120,000 EUR annually. Visa sponsorship is not available.

Location

Fully remote, with a preference for candidates based in Germany or Austria and availability during Central European Time hours. Occasional in-person collaboration in Vienna is possible.