Requirements
- 3+ years of industry experience applying machine learning methods, with a strong focus on recommender systems, search, ranking, or personalization ,
- Strong proficiency in Python for production ML systems ,
- Experience with A/B testing and experimentation frameworks to measure model impact ,
- Familiarity with cloud platforms (AWS, GCP, or Azure) and containerized environments ,
- Familiarity with SQL and NoSQL databases ,
- Degree in computer science, machine learning, statistics, or equivalent work experience

What the job involves
- We are looking for a Senior Machine Learning Engineer to join our Personalization team in Barcelona ,
- You will design and build systems that deliver highly relevant, personalized experiences across our digital products ,
- This role sits at the intersection of backend engineering, data, and applied AI—leveraging modern architectures and machine learning techniques to connect users with the most relevant content ,
- You will play a key role in building scalable indexing,



retrieval and ranking systems that serve personalized content to millions of readers in real time ,
- You will partner closely with product, data science, and engineering teams, bringing technical depth and sound judgment to architectural decisions, model design, and evaluation methodology ,
- Design, build, and operate personalization systems and services powering content discovery and user engagement ,
- Develop and improve ML models across the whole personalization stack, from candidate generation to final ranking ,
- Use data-driven methods to improve candidate retrieval, leveraging embeddings, two-tower architectures, and user/content signals ,
- Drive experimentation and A/B testing to measure impact and iterate on models and features ,
- Leverage LLMs to enhance content understanding and feature extraction ,
- Optimize systems for performance, latency, and scalability across high-traffic environments ,
- Contribute to engineering best practice

📌 Senior ML Engineer, Personalization (España)
🏢 Dow Jones
📍 España