AI/ML Engineer
About this role
What will you do?
As a AI/ML Engineer at Rebtel you will define how AI is done at Rebtel. What tooling we standardise on, how we evaluate models we put in front of real users, what "good" looks like for our prompts and our pipelines. AI is going from a side project to the core of how Rebtel operates and what we ship to our users. We're hiring the second engineer on our ML/AI subteam to help build it classical ML for the business, LLM-powered systems for the product, and a clear production mindset on both.
You'll sit inside the Data team, report to our Head of Data, and partner with one other ML/AI engineer to shape this capability from the ground up.
Areas of ownership: You'll own work across two complementary tracks, and you'll ship in both.
Classical ML, in production, for operational leverage
Risk and fraud models across payments, top-ups, and account behaviour
Churn prediction and retention modelling on a user base of a million-plus
Forecasting, pricing, segmentation, and the next batch of operational problems we haven't tackled yet
Owning models end-to-end scoping with stakeholders, building, deploying, monitoring, retraining
LLMs and AI agents, from internal automation to in-product features
Start with our customer support agents and automations: RAG pipelines, prompt orchestration, tool-use, evaluation harnesses
Move LLM capability into the product as user-facing features
Help guide the company on where AI actually creates leverage, what to build, what to buy, what to ignore and turn the good ideas into shipped systems
Requirements
- You are an excellent communicator and collaborator. We work in English, but you will hear many languages in our Stockholm office
- 4+ years of hands-on ML engineering in Python, with real production ownership not just notebooks
- Strong fundamentals in classical ML: feature engineering, model selection, validation, and the unglamorous parts of keeping a model healthy in prod
- A genuine production mindset: monitor