Senior Data Scientist (AI Search & Ranking)

TL;DR

Senior Data Scientist (AI Search & Ranking): Developing AI-powered search and ranking systems for a global metasearch engine with an accent on semantic retrieval, query understanding, and personalized recommendation algorithms. Focus on building scalable ML models, optimizing search performance, and driving product outcomes through A/B testing and causal inference.

Location: Must be based in or be able to relocate to Düsseldorf, Germany (Hybrid role with flexibility for remote work within Germany/specific regions).

Company

A leading global travel metasearch engine that helps millions of users compare hotel prices and find deals through cutting-edge technology and data-driven insights.

What you will do

• Analyze large-scale datasets to derive actionable insights into search quality and user behavior.
• Develop and productionize advanced machine learning and deep learning algorithms for search and ranking.
• Design scalable search architectures integrating semantic retrieval and query understanding.
• Lead end-to-end ML initiatives from concept to production deployment.
• Perform quality assurance and provide technical mentorship to junior team members.
• Collaborate cross-functionally with product and engineering teams to enhance user satisfaction.

Requirements

• 5+ years of experience in search, information retrieval, NLP, or machine learning.
• Master’s or PhD in Computer Science, Machine Learning, or related field.
• Deep expertise in semantic search technologies, vector databases, and Learning-to-Rank.
• Proficiency with LLMs, transformer architectures, and modern ML frameworks.
• Strong coding skills in Python and SQL.
• Proven ability to design and analyze large-scale A/B tests and causal inference experiments.

Nice to have

• Experience in recommender systems.
• Strong stakeholder management and communication skills.

Culture & Benefits

• Comprehensive visa support and relocation package for international candidates.
• Flexible working hours with 2 office days per week and annual remote work allowance.
• Professional development focus with coaching, workshops, conferences, and library access.
• On-site facilities including a gym, sports classes, and canteen with a daily allowance.
• Inclusive environment with support for parents including childcare assistance.

Hiring process

• Video Introduction and Introduction Call.
• Case Study and Technical Interview.
• Stakeholder and Leadership Interview.