Senior Full Stack Engineer (f/m/d)

About us:

Kyan Health is an AI-powered enterprise solution that connects employee well-being with measurable business impact. Using predictive analytics, Kyan helps companies monitor and reduce risks like absenteeism, turnover, and presenteeism. We believe in harmonizing work and life, fostering a positive environment that champions performance and personal growth and well-being at the same time. Our culture thrives on innovation, collaboration, and the well-being of every team member. Some things we’re proud of 🧠 Building an industry leading solution for mental well-being 🌎 300.000+ users across 90+ countries 🤝 Partnered with 200+ licensed psychologists and coaches 💲 €15M+ venture capital raised from renowned investors 🎁 Awesome benefits, including unlimited access to our Comprehensive Mental Health App About The Role Kyan Health is building the most advanced AI-augmented mental health and wellbeing platform in Europe. Our mission is to bring high-quality, clinically-grounded psychological support to employees and families across multiple countries, languages, and cultural contexts — with AI playing a central role.

We are looking for a Senior Full Stack Engineer with deep AI experience, particularly in:

AI agents & multi-step reasoning systems LLM application architectures Tool-calling, retrieval, orchestration, and evaluation Modern AI toolchains and best practices

• You will work closely with engineering, data, product, and clinical teams to build our AI features end-to-end and help shape the future of our platform.
• This is a role with massive influence — we’re early enough that your architectural choices, code, and AI expertise will have a lasting impact.

Our stack (You don’t need all of this, but strong React/TypeScript + AI foundations are essential.) Frontend TypeScript React + Next.js React Native (plus React Native Web) Component libraries/design system Backend & Data Node.js (TypeScript) Event-driven and service-oriented architecture BigQuery, PostgreSQL, NoSQL stores Vector databases, retrieval pipelines Cloud infra (GCP/Azure) AI Tooling & Ecosystem OpenAI API & Assistants Azure OpenAI (GPT, embeddings, structured outputs) LangChain, LlamaIndex, OpenAI function calling Agent frameworks (custom, or e.g. LangGraph-style) Evaluation suites, guardrails, prompt tooling Monitoring + model observability

What You'll do:

AI Architecture & Agentic Systems

• Design and implement coding agents, task-specific AI agents, and multi-step workflows that power user-facing features.
• Build and refine retrieval pipelines, embeddings flows, and hybrid RAG/logic systems.
• Architect robust prompting, function-calling, and tool orchestration systems.
• Full Stack Product Development
• Own features across Next.js, backend services, and mobile/web.
• Translate product and clinical requirements into AI-powered user experiences.
• Work with data pipelines, BigQuery, analytics, and experimentation frameworks.
• Cross-platform UI Systems
• Build and evolve our shared React/React Native component library and design system.

Ensure accessibility, performance, and multi-market language support. Technical Leadership Set coding standards for AI-integrated features. Mentor others on AI architecture, LLM patterns, evaluation, and failures modes. Challenge assumptions, propose better approaches, and push for pragmatic, responsible AI usage. Who We're Looking For

Required:

• Senior-level engineering experience, ideally 6+ years, with strong autonomy.
• Deep understanding of the modern LLM ecosystem: models, embeddings, fine-tuning, structured outputs, evaluation, latency/cost tradeoffs.
• Hands-on experience building production AI agents

(e.g., planning/multi-step systems, tool-calling, retrieval-integrated workflows).

• Strong React + Next.js + TypeScript experience.
• Experience building cloud-hosted applications (Azure, GCP, etc.).
• Solid backend experience with Node.js, APIs, data modeling, auth, performance.
• Familiarity with BigQuery or similar analytical data warehouses.
• Strong product awareness — focus on usability, clarity, and delivering outcomes.
• Pragmatic engineering mindset: readable code, clear patterns, low complexity.

Nice to Have:

• Prior work in healthtech, HR tech, or other sensitive domains.
• Experience with evaluation frameworks, AI observability, or human-in-the-loop workflows.
• Background in mobile development (React Native, native iOS/Android).
• Experience with multi-language or multi-market products.

Why Join Us

• Make an Impact: Your work will directly contribute to improving mental health in workplaces around the world.
• Ownership: You'll have the chance to take ownership of our content production processes
• Innovative Environment: Work in a greenfield space where your ideas aren't just welcome—they're essential.
• Collaborative Team: Join a supportive team where collaboration and innovation are at the heart of what we do. We are an easy to work with & low ego team, and want to keep it like that.
• What's In It For You

Full Access to Our Comprehensive Mental Health App:

• Unlimited use of Kyan Health's AI well-being companion "KAI" and guided meditation courses.
• Unlimited sessions with licensed psychologists.
• Unlimited sessions with ICF-certified coaches.
• Competitive compensation, adjusted for experience.
• Meaningful stock options in a rapidly growing AI-driven healthtech company.
• Work with a mission-driven team and product that genuinely helps people.
• Hybrid in Berlin or remote within CET±4.
• Autonomy, ownership, and a chance to shape foundational AI systems from the ground up.

Interview Process:

CV Check Get to know Kyan, Girish (30 minutes Call) Get to know your manager, Nacho (45 minutes Call) Team Interview(s), Hans & Victoria ( 30 minutes each call) Onsite Live Coding Exercise (Nacho/Hans/Victoria, 120 minutes) Offer Stage: Meet the founder(s) (30 minutes) / Reference check / Offer

• Please note: We only accept applications submitted through our official Careers Page. Applications submitted via other channels will not be considered.

🤩We are excited to hear from you! ⛔Please note that we do not work with agencies or external recruiters.