Senior Fullstack Engineer

Role Summary

Join a fast-growing European AI voice tech company building an AI-powered phone assistant for small and medium-sized businesses. As a Senior Fullstack Engineer, you'll take end-to-end ownership of product features — from idea and prototype through architecture, implementation, and release — on a remote-first team with real customer impact.

Responsibilities

• Own features across the full stack, from discovery and architecture to shipping and measuring outcomes.
• Engage directly with customers, partners, and Sales to surface real pain points and inform what gets built.
• Form hypotheses and validate them quickly through lightweight experiments before committing to large-scale solutions.
• Instrument features and gather metrics to enable data-driven product decisions.
• Build pragmatic, scalable software balancing immediate customer value with long-term maintainability.
• Communicate and collaborate asynchronously, prioritizing shipping over excessive meetings.
• Act with radical ownership — push initiatives forward without waiting for permission.

Requirements

• 5+ years of experience in fullstack engineering with end-to-end delivery responsibility for customer-facing applications.
• Strong hands-on experience with Node.js, TypeScript, NestJS, and React .
• Experience integrating LLMs (e.g., OpenAI) into production software applications — a significant plus.
• Product mindset: you measure success by customer value, not lines of code.
• Skilled at extracting actionable insights from direct conversations with users, partners, and sales teams.
• Comfortable owning analytics, tracking, and the data layer needed to support product decisions.
• Experience deploying AI-enabled services on cloud infrastructure in Europe (e.g., Microsoft Azure) is a bonus.
• Familiarity with GDPR and EU AI Act considerations for AI-powered services is a plus.
• Experience working in a high-growth startup environment.
• Strong CS fundamentals and sound judgment when trading off effort, quality, and speed.
• Native-level German proficiency is required — the product serves a German-language market.
• Salary range: €80,000 – €120,000 annually. Visa sponsorship is not available.
• Fully remote, with a preference for candidates based in Germany or Austria (CET timezone overlap expected). Optional access to a Vienna office.