Senior Software Engineer (m/f/d) | Fullstack for AI Products

How does a RAG system remain precise when documents grow from a thousand to a hundred thousand? How do you cleanly orchestrate multiple model providers behind a single interface? While others are still showing prototypes, our clients have been working with them for a long time - with their data, their rules, hosted in Germany. As a Senior Engineer, you will be responsible for core functions and architecture of our platform, from retrieval to the frontend - and you will develop them the way we work: AI-supported, with coding agents as part of the toolkit, and with real creative freedom for your ideas. Are you looking for a role where technical depth and product responsibility come together? Then we should get to know each other!

• Architecture & Implementation You design and scale distributed systems and microservices - always with an eye on maintainability, stability, and the question of what will still hold up in two years. 
• Building AI Features That Last in Everyday Use You develop the core functions of our platform - from RAG-based knowledge bases and AI apps for individual departments to voice, translation, and analytics functions. 
• Delivering Full-Stack You develop performant APIs, model data and databases, and implement modern interfaces in the frontend - from retrieval to the user interface.
• Data, Security & Multi-tenancy You model data for multi-tenancy and role-based permissions - so that no one gains access to anything they shouldn't see through the AI. You consider encryption, data minimization, and auditability from the outset. 
• Considering Operations & Observability You ensure that the quality, costs, and behavior of AI features remain visible in operation - with evaluations, monitoring, and clear guardrails so that the platform remains stable and efficient even with growing usage.
• Mastering Complexity You further develop existing systems, create clear structures, and reduce technical debt where it becomes expensive in the long term, and leave it where it does not. 
• Developing with AI Support – and Setting the Standard for It You naturally work with coding assistants and agents, get more out of them than just autocomplete, and know exactly where their limits are. You test new tools and workflows early, evaluate them honestly, and establish within the team how we can use them meaningfully.
• Advancing the Team & Product You work closely with Product Owners, UX, and our consultants, translate real customer use cases into technology, make technical decisions transparent, and advance our junior developers technically through code reviews and mentoring. 

• At least 5 years of experience in developing complex software systems, ideally in the AI or SaaS/Cloud environment
• Very good TypeScript skills, experience with Node.js and ideally frameworks like NestJS 
• Very good knowledge of software architecture for distributed systems - microservices, API design, scaling 
• Experience in frontend, e.g., with Vue.js, and a good understanding of full-stack contexts 
• Sound knowledge of working with databases (e.g., PostgreSQL), data modeling, and performance optimization 
• Experience with cloud platforms (e.g., AWS), Docker, and operating SaaS applications 
• AI-supported development is part of your everyday life: You are proficient with coding assistants and agents (e.g., Claude Code, Cursor, Copilot), know their limitations, and critically examine generated code rather than trusting it 
• You are at the pulse of development: You actively try out new tools, models, and workflows and bring the good ones to the team - experience with agentic setups (e.g., coding agents in the cloud, MCP integrations, automated reviews) is a strong plus 
• Deeper understanding of modern AI/LLM concepts like RAG, Function Calling, Embeddings, or Agents
• Clean code, testing, and code reviews are a matter of course for you, and you enjoy advancing junior developers technically through reviews and mentoring 
• You make technical decisions and can credibly justify them - in German and English 
• Experience with GDPR, ISO 27001, or the EU AI Act is a plus 

• Start & Welcoming as you deserve! Structured onboarding with real contacts - so you can hit the ground running from day one.
• Remote Work Home office within Germany or working in our modern office in Offenburg? Work the way that suits you best.
• Working AI-first, instead of just talking about it We provide licenses for Claude Code, Cursor, Copilot & Co. You can try out new tools and models instead of requesting them - and your findings change how the entire team works. 
• Short paths, no decision-making bodies Architectural decisions are made by the team that will operate them later. Your ideas land in the product, not in a backlog archive. 
• Company pension scheme with a 20% employer contribution - significantly above the legal standard.
• You decide whether it's a Hansefit membership or €50 per month via Spendit Card - your benefit, your choice.
• Vacation that grows with you: 30 days of annual leave + Christmas and New Year's Eve off - and with increasing company tenure, additional days are added. 
• Job ticket or JobRad - we make your commute to the office easier and greener.
• Celebrations are part of it - Quarterly Allhands Events, summer party, Christmas party, or just because - we know how to pop the corks.
• A team that truly matters. Flat hierarchies, quick decisions, and an open ear for what moves you personally as well.

For us, transformation is not a trend, but our mission: Since 1995, the avenit Group has been supporting companies in repositioning themselves for the digital future - holistically, strategically, and with a clear focus on sustainable success. With avenit and Vusyon, we combine two strong forces - many years of leading digital expertise and state-of-the-art AI technology - into one partner for tailor-made solutions that truly work. We believe that sustainable success is created on an equal footing; in genuine dialogue with our clients. Our 60 colleagues make this vision a reality every day. Become part of a team that not only thinks about the future but shapes it.

Our innovative AI team at Vusyon GmbH is looking for reinforcement to further develop our AI platform for the mid-market. Curious what makes us special there? Find out more here: https://vusyon.ai/