Senior Fullstack Engineer

About the Role

This is a high-ownership Senior Fullstack Engineer position at a fast-growing European Voice AI startup serving thousands of SMEs. You will own features end-to-end, from initial concept through production deployment, and play a direct role in shaping the product roadmap as the company scales.

What You'll Do

• Build and ship full-stack features nearly daily using
• NestJS and
• React
• , owning the full lifecycle from prototype to production.
• Engage directly with customers through support, feedback sessions, and user testing to identify and validate real needs.
• Prioritize ruthlessly, breaking features into their highest-value parts and iterating based on real customer insights.
• Take on increasing responsibility for feature and opportunity prioritization within the Voice AI product as you grow into the role.
• Work in a deep-focus environment with minimal meetings, maximizing time for meaningful engineering work.

What We're Looking For

• 5+ years of hands-on fullstack engineering experience delivering end-to-end features in SaaS products.
• Strong proficiency with TypeScript, React, and Node.js
• ; experience with NestJS is strongly preferred.
• Substantial experience across both backend and frontend, with a track record of shipping customer-facing applications end-to-end.
• Native German speaker
• (required to actively contribute to AI product development and customer-facing language quality).
• Fluent English for team and cross-functional communication.
• Experience collaborating directly with customers, partners, or sales teams to understand pain points and define product value.
• Comfort with product discovery: forming hypotheses, running experiments, and using metrics to support data-driven decisions.
• Pragmatic, autonomous engineering mindset, you know how to cut scope without cutting value and thrive without heavy process overhead.
• Bonus: experience integrating LLMs (such as OpenAI) into production applications, deploying AI services on cloud infrastructure in Europe, or familiarity with GDPR and EU AI Act considerations.