Senior Founding Engineer (m/f/d)

We are looking for a Senior Founding Engineer (Full-Stack) to join a small founding product team in Berlin. Someone who wants real ownership, sweats the small UX details, and would rather ship something today and learn from it than polish something no one's used yet.

The role:

• Take features from idea to shipped product and back again — frontend, backend, all of it, start to finish.
• Treat speed as a feature. The biggest risk isn't messy code, it's building the wrong thing — so validate fast and adjust.
• Get close to the people using the product. Talk to customers directly, feel their workflow pain, and let that drive what you build next.
• Work hand-in-hand with the design lead to make the product feel genuinely premium, not just functional.
• Push the engineering craft forward — better patterns, better tests, better developer experience — without ever slowing down the shipping cadence.
• Think and act like a founder: ruthless prioritization, real ownership of outcomes, a voice in what "good" looks like here.

Who we're looking for:

• Someone with real product instinct — UX, clarity, and the tiny details that separate software that feels right from software that just works.
• A genuinely strong backend engineer who's built and scaled production systems and isn't afraid to go deep.
• Pragmatic over perfectionist — you know the difference between "ship to learn" and "ship because we're lazy."
• Clean, maintainable code, and a habit of communicating context before someone has to ask for it.
• Someone energized by talking to customers and understanding real constraints, not just building in a vacuum.
• Comfortable in a modern stack (TypeScript, React, Next.js, Node.js, Postgres, Prisma, or similar)
• Hands-on experience building AI product features — LLMs, agents, workflows, evaluation.
• Mobile experience (Flutter, React Native, or similar).