Data Scientist

Benodigde opleiding: HBO

For the client, we are looking for Data Scientist GenAI / Chatbot:

Important:

• We are looking for 1 FTE.
• We will close the vacancy before the indicated deadline when we have received enough professionals.
• Please clearly indicate in the motivation field whether the candidate has any planned vacation or special leave during the duration of this assignment.
• Please provide in the CV whether an internal reference can be requested. If the candidate is currently working at, or has recently worked at, the client, we would appreciate receiving the name and job title of the relevant team lead.
• Language: English
• ZZP Allowed: No.

Hybrid working: Thursday in office (Location Winthontlaan, Utrecht until further notice).

Level: Medior–Senior.

Application process details:

The process consists of an initial one-hour interview with two of our Data Scientists to assess your technical skills, followed by a 30-minute conversation with the team manager to evaluate team fit.

As Data Scientist (GenAI / Chatbot), you know the secrets of making AI assistants perform at their best.

You will work at the intersection of data, engineering, and product thinking, helping to improve the quality and effectiveness of chatbot systems. Rather than building foundation models, your focus will be on understanding chatbot behaviour, identifying weaknesses, and translating insights into meaningful improvements.

You help answer a fundamental question:

“Why is this chatbot not doing what we expect, and what context or structure does it need?”

You will assess current solutions against state-of-the-art approaches and drive innovation across retrieval, generation, reasoning loops, tool calling, and related GenAI capabilities.

Your Responsibilities:

• Analyse chatbot outputs and identify the improvements with the greatest impact;
• Diagnose context gaps and determine what additional information agents require;
• Partner with product managers and engineers to define evaluation criteria for agent performance;
• Work directly with use-case teams and stakeholders to understand real-world scenarios and translate feedback into improvements;
• Improve retrieval mechanisms, data structuring, and onboarding of contextual sources;
• Design evaluation frameworks that enable rapid, large-scale experimentation and continuous innovation;
• Translate functional requirements into actionable technical improvements.

Your Talent:

• You bring a strong analytical mindset and a passion for understanding why AI systems behave the way they do;
• Strong understanding of GenAI systems;
• Experience with LLM-based applications;
• Experience with retrieval-augmented systems;
• Strong understanding of prompts, context windows, retrieval, and grounding;
• Ability to evaluate output quality and explain why results are effective or ineffective.

Technical Integration Skills:

• Familiarity with API integrations, batch synchronisation, and structured and unstructured data;
• Comfortable collaborating closely with engineers;
• Ability to troubleshoot data flow and context ingestion issues.

Analytical and Evaluative Mindset:

• Ability to design evaluation frameworks beyond traditional machine learning metrics;
• Understanding of functional context and user behaviour;
• Ability to operate effectively between engineering and product domains.

Clear Communicator:

• Ability to explain context gaps and reasoning to engineers, product managers, and stakeholders;
• Ability to create clear and effective improvement proposals.

Nice to Have:

• Background in human-in-the-loop evaluation.

Who Will Thrive Here:

This role is ideal for someone who enjoys understanding why AI systems behave the way they do and how they can be improved. You enjoy debugging not only code, but behaviour. You think structurally, connect the dots, and have a strong intuition for what good performance looks like.

Additional Information:

• All departments are working hybrid, in terms of the client @anywhere policy;
• Due to the congestion at the parking lot the client location Croeselaan in Utrecht, a new parking policy will be introduced as of April 2026. From Monday through Thursday, external staff will no longer be able to park at the Croeselaan. Parking for external staff will remain permitted on Fridays only;
• Please note: midlance constructions are not allowed according to the client policy. Do not offer candidates via this construction. This will be investigated during the screening;
• Suppliers must be aware of the laws and regulations regarding employment conditions and the client’s Collective Labour Agreement. This assignment is placed in scale 9;
• We would like to receive the personal motivation of the candidate and CV in English;
• A candidate should be submitted exclusively to the intermediary – the client during the exclusivity period of 4 business days on one request;
• Furthermore, the candidate has to be available throughout the entire duration of the assignment;
• All submitted candidates must be in possession of a valid Passport or ID card, which must be taken along to the interview and at the start of the assignment;
• Pre-employment screening: If the candidate is selected to start, a pre-employment screening will be executed. As of July 1, 2026, a new PES regulation applies. The PES is outsourced to an external party. More information can be found in Annex A. Your candidate is only allowed to start after the pre-employment screening has been completed successfully;

This agreement can be requested in advance;

IMPORTANT!:

• Complete all candidate details correctly. Enter the candidate's contact details under ‘email address and telephone number’! The same applies to the address. This is information the client needs to receive with the submission. Incomplete/incorrect submissions risk being rejected.