Machine Learning Engineer II

Role Description

About the team:

The GenAI Applications team, part of the Data & AI Marketplace organization designs and delivers agentic, ML‑powered solutions for some of Booking.com’s most impactful customer experiences, including booking search, trip planning, and broader trip helpfulness journeys. Working closely with product, engineering, and ML science partners, the team builds end‑user GenAI applications and conversational agents on top of a shared multi‑agent backbone, turning ambiguous, high‑level ideas into scalable, production‑ready features.

Their mission is to standardize GenAI flows on a unified agentic architecture, democratize access to in‑house LLMs and agents fine‑tuned on Booking data, and make it significantly easier for product teams across the company to ship safe, high‑quality AI experiences at scale.

About the role:

As a Machine Learning Engineer II in this application-focused role, you will build end-user GenAI products on top of existing infrastructure, such as AI Trip Planner, Free Text Search, and Trip Planning Hub. You will implement GenAI-powered features and work closely with product managers, scientists, and a variety of stakeholders to translate vague or evolving requirements into robust, production-ready ML solutions, typically owning a specific application area.

Key Job Responsibilities and Duties:

• Work in a multi-disciplined, highly skilled team where you will be developing scalable production-grade data and ML pipelines across the entire ML cycle while working closely with the teams’ applied machine learning scientists
• Work primarily with the Google Cloud Platform, utilizing and maintaining the infrastructure for technologies like BigQuery, DataProc, Cloud Composer, Airflow and diverse set of ML frameworks
• Be responsible for SLIs/SLOs for ML systems, ensure system and model health, monitor data quality, performance and business impact, and devise mitigation plans
• Drive a culture of quality for all ML practitioners, maintain data security, integrity and quality, and make choices over the right technologies and coding methodologies
• Identify underlying issues and opportunities across the ML development cycle and introduce tools to be used within and outside the team for efficient development and testing
• Continuously evolve your craft, keeping up to date with the latest technologies
• Collaborate with relevant ML teams across the company to improve, scale and extend machine learning tooling and infrastructure

Qualifications and Skills:

• 3+ years of relevant work experience, involved with the application of Machine Learning Engineering to business problems in a commercial environment
• Strong skills in coding and problem solving. Proficiency in at least one programming language; preferably Python and strong command of SQL is strictly required. Knowledge of Java is a plus
• Strong working knowledge of big data retrieval and processing tools
• Demonstrable experience of multiple machine learning facets, such as working with large data sets, experimentation, scalability and optimization
• Experience running Machine Learning systems in production is a must, with knowledge on how to generate predictions for ML frameworks with high throughput
• Experience with data-driven product development: analytics, A/B testing, etc.
• Experience working in a cloud environment is a plus
• Willingness to learn and understand complex and multidisciplinary business problems and concepts related to booking.com business operations especially in marketing and finance fields
• You have a ‘can do’ attitude and you act proactively and not reactively
• BSc or higher in Computer Science, Artificial Intelligence, Software Engineering, or related fields
• Excellent English communication skills, both written and verbal

Benefits & Perks - Global Impact, Personal Relevance:

Booking.com’s Total Rewards Philosophy is not only about compensation but also about benefits. We offer a competitive compensation and benefits package, as well unique-to-Booking.com benefits which include:

• Annual paid time off and generous paid leave scheme including: parent, grandparent, bereavement, and care leave
• Hybrid working including flexible working arrangements, and up to 20 days per year working from abroad (home country)
• Industry leading product discounts - up to 1400 per year - for yourself, including automatic Genius Level 3 status and Booking.com wallet credit
• Living and working in Amsterdam, one of the most cosmopolitan cities in Europe
• Contributing to a high scale, complex, world renowned product and seeing real-time impact of your work on millions of travelers worldwide
• Working in a fast-paced and performance driven culture
• Opportunity to utilize technical expertise, leadership capabilities and entrepreneurial spirit
• Promote and drive impactful and innovative engineering solutions
• Technical, behavioral and interpersonal competence advancement via on-the-job opportunities, experimental projects, hackathons, conferences and active community participation