Senior Fullstack AI Engineer (f/m/d)
At a glance
Senior AI Engineering role at StackFuel. Berlin · full-time.
Pay not stated AI Engineering salary
aimlroles summary, based on the employer's posting.
What you'll do
- Build the adaptive learning platform and AI software end to end, making key architecture choices yourself
- Add features to the existing learning framework while continuing to improve how it works
- Turn LLM learning support, adaptive paths and content generation into reliable, measurable, cost-efficient features
- Create internal tools and AI automations that help Learning Coaches, Client Operations and Sales work more efficiently
- Work alongside engineering, Content Engineering and Portfolio Leads
What you bring
- At least five years in full-stack development, with several years owning architecture, technical choices or mentoring
- You use AI tools in daily engineering and have applied LLM APIs in products, including prompt design, outputs, tool use and evaluation
- You have delivered software with Python frameworks and TypeScript using React or Next.js
- You work confidently with PostgreSQL and migrations, and bring testing, CI, Docker deployment and observability experience
- You communicate fluently in business English; German at B1 to B2 level is a plus
Who this fits
This role suits a senior engineer who wants to build a new platform while continuing work on an existing learning framework. AI tools are expected to shape how you build software, and internal tools for Learning Coaches, Client Operations and Sales are a central part of the job. The role is hybrid, with the team usually working from the Berlin office three days a week.
From the employer
Job description
For years, StackFuel has been one of Germany’s leading providers of data and AI training. Since early 2026, we have been part of Multiverse, Europe’s only EdTech unicorn and the continent’s largest AI upskilling platform. Together, we are pursuing a clear goal: to make 100,000 employees in Germany AI-ready and close the country’s data and AI skills gap.
To make this happen, we are building a next-generation adaptive learning platform from Berlin, AI-first from the ground up. Alongside this, we develop software tools and automations that integrate into our customers’ B2B platforms. As a Senior Fullstack AI Engineer (f/m/d), you’ll play a key role in shaping this platform and these software tools, from the database to the frontend. Your work directly reaches thousands of learners and contributes to the transformation of mid-sized and large German companies.
Your 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
What you bring
5+ years of experience in full-stack development, several of them with senior responsibility (architecture, technical decisions, mentoring)
You work AI-first and naturally use AI tools in your day-to-day engineering; the agentic SDLC isn’t a foreign concept to you but a target vision
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
This role probably isn’t for you if…
This role is probably not the right fit if you only want to work on greenfield projects. Alongside building our new platform, you’ll also continue developing our existing learning framework, and both are equally part of the job. It’s also not a good fit if you see AI tools as a nice extra rather than something that fundamentally changes how we build software. And if internal tools appeal to you less than the big product, you probably won’t be happy here: the back office for Learning Coaches, Client Operations, and Sales is a central part of the role, and it’s often where you’ll feel your impact most quickly.
What 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.