Senior Data Scientist at Refractal
Montenegro
Posted
on-site · full_time · Visa sponsorship
Apply for this role at Refractal
Responsibilities:
- Train, tune and deploy classifiers for prompt injection, data exfiltration, policy violations and other risky AI behaviours.
- Design low-latency models (distilled/small models, rules+ML ensembles) suitable for production constraints.
- Analyse production telemetry to detect drift, blind spots, false-positive costs and emerging attack patterns.
- Build evaluations, benchmarks and labelling processes; convert new attack cases into training data.
- Track model performance per customer and translate policies/regulatory needs into measurable controls.
Requirements:
- 5+ years applied ML/data science experience with models shipped to production.
- Strong Python and PyTorch (or similar) skills and solid statistics for evaluation.
- Hands-on NLP/LLM experience: fine-tuning, embeddings, classification, LLM-as-judge patterns.
- Experience measuring fuzzy problems: labelling, inter-annotator agreement and drift detection.
- Clear communicator who can explain trade-offs to engineers and customers.
- Nice-to-have: adversarial ML, safety or content-moderation experience; local languages (Montenegrin/Serbian/Bosnian/Croatian).