Senior Data Scientist

Senior Data Scientist | Brussels

At Exsolvæ, our consultants carry the title of Solver, and it's a title you earn. We take the development of every Solver seriously, each one belongs to a Core Domain, works with a Leader who actually follows their progress, and presents their work in Cerebro sessions to colleagues who know the field as well as they do. It's a demanding place, on purpose.

The Data Science & AI Core Domain serves some of the biggest names across finance, retail, automotive, etc.

For this mission, you'll join the marketing data science team of a leading company in Belgium, building responsible AI models that make campaigns more relevant for millions of customers.

That's the work we're hiring for.

Your role, on mission

• Build responsible AI models that make marketing campaigns more relevant and impactful, from target group selection to customer journey driven campaigns (next best action)
• Use LLMs and fine-tuned models to turn large volumes of unstructured text, such as client interaction notes and web analytics data, into insights on products discussed, customer intent and feedback
• Own the full lifecycle: capturing business needs, assessing feasibility, building models and data pipelines, deploying and monitoring them in production
• Set up rigorous evaluation: experiment design, impact measurement, guardrails and validation of LLM-driven predictions
• Build feedback loops and dashboards that let business users correct predictions and keep models learning
• Bring MLOps best practices to the team (MLflow, reproducible models and datasets)
• Translate technical results into clear, actionable insights for business owners, and guide junior data scientists along the way

Your role, within the community

• Share what you learn: Cerebro sessions, co-built playbooks, code reviews between Solvers
• Mentor peers and be mentored: seniors who enjoy passing on what they know do well here
• Help shape where the Core Domain goes next

Must-haves

• Master's degree in a quantitative field (statistics, mathematics, computer science); other academic backgrounds with substantial data science experience are welcome
• Senior profile: minimum 5 years of relevant experience in data science
• Expert Python and its data science ecosystem (scikit-learn, PyTorch, TensorFlow), with solid engineering practices (git, bash, SQL)
• Expertise in customer journey modeling
• Solid understanding of statistical methods, experiment design and machine learning, both traditional and deep learning
• Proven expertise using LLMs for text classification, including interpretability, guardrails and validation of LLM-driven predictions
• Fluent English, plus fluent French or Dutch
• Based in Belgium and available on-site in Brussels 50% of the time
• A genuine desire to be part of a community: you share what you know and you show up for the collective moments

Strong assets

• Incremental learning and closed feedback loops
• Uplift modeling
• Marketing Mix Modeling and optimization under constraints
• MLOps: MLflow, model monitoring and delivery pipelines
• SAS, Streamlit
• Financial services background

Joining Exsolvæ, concretely

• A community before anything else: a Core Domain led by a Leader who follows your development, Cerebro sessions where Solvers present and learn, playbooks built together
• A Knowledge & Networking budget to keep learning and stay plugged into the ecosystem (emerging AI topics, MLOps, AI governance)
• A followed career path with a dedicated Manager, regular check-ins, an evolution committee that formalises your progression and issues recommendations
• Long-run missions at leading companies, in production
• A permanent employee contract, with a competitive package

Interested, or know someone who fits? Apply here or reach out to us!