Senior Fullstack AI Engineer (f/m/d)

About the Position

Senior Fullstack AI Engineer (f/m/d)

StackFuel, a leading provider of data and AI training in Germany, is part of Multiverse, Europe’s only EdTech unicorn. We aim to make 100,000 employees in Germany AI-ready by building a next-generation adaptive learning platform and software tools. As a Senior Fullstack AI Engineer (f/m/d), you will shape this platform and contribute to transforming mid-sized and large German companies.

Location

Berlin, Germany

Employment Type

Full time

Location Type

Hybrid

Department

Engineering

Responsibilities

• Develop our adaptive, AI-first learning platform and software-based AI solutions end-to-end, independently making key technical architecture decisions.
• Implement new features and requirements in our existing learning framework, balancing new development with ongoing improvements.
• Build AI features into the platform, such as LLM-powered learning support, adaptive learning paths, or automated content generation, and ensure they run reliably, measurably, and cost-efficiently.
• Build internal tools and AI automations for Learning Coaches, Client Operations, and Sales to help these teams work more efficiently.
• Work closely with the entire engineering team, our Content Engineering team, and the Portfolio Leads.

Requirements

• 5+ years of experience in full-stack development, several of them with senior responsibility (architecture, technical decisions, mentoring).
• Hands-on experience with LLM APIs in products: prompt design, structured outputs, tool use, and evaluation of model outputs.
• Experience with end-to-end development using Python (FastAPI or Django) and TypeScript/React/Next.js.
• Confident with PostgreSQL and schema migrations.
• Discipline in testing and CI (e.g. pytest, typed code, GitHub Actions or similar).
• Experience with Docker-based deployment and a foundation in observability.
• Business-fluent English and ideally German at B1–B2 level.

Nice to Have

• Experience with FastAPI and Django.
• Strong knowledge of observability.

We Offer

Work culture

A solution-oriented, data-driven way of working, an open feedback culture, and strong team spirit. Two Trustees, elected by the entire StackFuel team, act as a neutral, confidential point of contact for your questions and concerns.

Ownership

Take on responsibility from day one, actively contribute your own ideas, shape processes sustainably, and have a real influence on how we work.

Hybrid working

We work in a hybrid model and are usually in our Berlin office 3 days a week.

Workation

Work from anywhere in the EU, the EEA, and Turkey for up to 10 days per year.

Room for exchange

Regular team exchanges, seasonal celebrations, and an always well-stocked kitchen make for a lively atmosphere.

Professional development

Take our online trainings to expand your skills and become an expert in data and AI.

About the Company

StackFuel is one of Germany’s leading providers of data and AI training, now part of Multiverse, Europe’s only EdTech unicorn. Together, we aim to make 100,000 employees in Germany AI-ready and close the country’s data and AI skills gap.