Backend Engineer - AI Document Processing

Who we are The GoCalma Startup was founded in 2025. Our HQ is in Zug. We simplify the personal office: we turn people's stacks of paper into clarity. We bring a household's private documents to one safe place, give people an overview and explain their finances in plain language. Why now We are still small and hiring our first team members. You join early, help shape how the company and the product work, and your decisions have real impact. This is not a role where you wait for tickets. You build things and see them reach real users. Our core values Open & Direct. We say what we think, early and clearly. Fun & Joy. We take the work seriously, not ourselves. Encourage & Challenge. We back each other and we push each other. No Half-Measures & Full Conviction. We commit, and we finish what we start. Tasks We're looking for our first Backend Engineer You own the API that powers our app and admin portal. You have a real say in architecture and data model, and you carry your work from idea to production. Goals of this role Own and evolve the backend so the app and admin portal stay fast, reliable and safe to change. Turn uploaded documents into structured, useful data: extracted, summarised, classified, named and easy to find again. Make our AI chat genuinely useful, so people get real answers about their own documents and topics like taxes, insurance and pension. ** Main responsibilities** Build and maintain our API for documents, checklists and the chat assistant in production. Develop the document pipeline: OCR, summarising, classifying, naming and making documents findable again. Build the AI chat that answers questions about a user's documents. It combines per-user context from past chats with a shared knowledge base (Markdown wiki) and covers topics like taxes, emergency documents, insurance, pension etc. Integrate external and potentially on premise AI providers for classification and chat, including streaming responses. Own the data model, use cases, permissions, security and multi-tenant logic, plus deployment and monitoring. The API mainly powers our B2C mobile app 24x7, and also serves fiduciaries and other organisations. Requirements What do we expect? ** Attitude** You identify with our mission. Curiosity to figure things out and the drive to execute them. You are comfortable building AI-assisted. We write around 80% of our code with AI, grounded in extensive documentation, and you keep ownership of design, review and quality. You care about handling sensitive data properly. Privacy is a foundation for us, not an afterthought. ** Hard skills** AI and LLM integrations, document processing, or running your own deployments. Experienced in building reliable backends. We currently use Ruby on Rails for the prototype, so Rails is a plus, but strong backend fundamentals matter more than any one framework. A real track record: things you built and shipped, not just courses you took. Strong API design and automated testing. Both are required, not optional. ** Soft skills** Stand up for your opinion, and stay open to other ideas. Keep the user at the centre of every decision. How we build We write around 80% of our code AI-assisted, grounded in extensive documentation. Good docs are how we keep this fast and safe: you write and maintain them, then let AI do a lot of the typing while you stay in charge of architecture, review and quality. If that sounds like a downgrade to you, this is not the right team. If it sounds like leverage, you will feel at home. What else do you need to know? We work flexibly. Full-time or part-time from 60%, hybrid, with our team based in Zug. We are open on where you work from, as long as we get real overlap and see each other regularly in Zug. ** What hiring process can you expect?** Apply. Send us a short note about who you are, plus a link to your GitHub or a project you are proud of. A link says more than a perfect CV. Apply with the keyword ‘Backend Developer 2026’ in subject. Short task. A small, realistic task, capped at 2 hours. You get honest feedback either way, guaranteed. Two interviews. One with the team on how you work, one on the mission and the fit both ways.