Key skills
TypeScriptReactNext.jsNode.jsNestJSLarge Language Models (LLMs)API developmentAI integrationGCPCI/CD with GitHub ActionsProduct mindsetCustomer mindsetAIRAGAgenticSales
About this role
1KOMMA5° is dedicated to building the energy system of the future with Heartbeat AI. As a (Senior) Product Engineer, you will take end-to-end ownership of features and workflows, collaborate with cross-functional teams, and leverage AI to enhance product development and efficiency.
Responsibilities:
- Own feature development end-to-end, from problem framing to production deployment and long-term maintenance
- Build and integrate AI-powered product experiences using LLMs, agents, and tool-use patterns
- Define feature scope together with PMs - engage with the "why", not just the "what"
- Contribute to architectural decisions, API design, and AI integration patterns across the teams
- Keep feedback loops short: prototype, ship to real users, observe, adjust
- Push back when something doesn't make sense and propose better approaches
Requirements:
- Strong fullstack proficiency in TypeScript, React / Next.js, and Node.js / NestJS
- Real, demonstrable experience building with LLMs, APIs, or MCPs - production use preferred
- A product and customer mindset: you think about user problems, not just implementation elegance
- Proven ability to own features end-to-end, from rough problem statement to shipped, maintained product
- Experience working closely with PMs and designers in a cross-functional team
- Excellent written and spoken English; German is a plus
- Residency in Germany
- Experience with agentic systems, tool-use patterns, or RAG pipelines
- Familiarity with the energy market, construction, sales, or climate tech context
- Prior experience in a startup or scale-up