Machine Learning Scientist - London

Salary: £70,000 - 110,000 per year

Requirements:

• Bachelors degree in Computer Science, Machine Learning, Artificial Intelligence, Engineering, Data Science, or a related technical field; or equivalent related professional experience.
• 5+ years of industry experience developing machine learning solutions in production environments.
• Proficient programming and software engineering skills in Python, including experience building production-grade services and APIs.
• Experience with machine learning frameworks such as TensorFlow and/or PyTorch.
• Experience owning machine learning solutions across the full lifecycle, including experimentation, evaluation, deployment, monitoring, and operational improvement.
• Experience building and operating production ML systems at scale.
• Understanding of distributed systems, data structures, algorithms, system design, low-level design, API design, and data modelling.
• Experience with batch and real-time data processing systems, databases such as Redis, and low-latency serving technologies such as KServe and FastAPI.
• Ability to partner effectively with cross-functional teams to deliver measurable machine learning outcomes.
• Preferred: Masters degree or PhD in Computer Science, Machine Learning, Artificial Intelligence, Statistics, Data Science, or a related STEM field.
• Preferred: Experience applying Generative AI and LLMs to customer-facing products and designing, building, or scaling RAG systems.
• Preferred: Experience in search, ranking, recommendations, personalisation, content intelligence, moderation, NLP, computer vision, or related AI domains.
• Preferred: Experience with Airflow or comparable workflow orchestration platforms.
• Preferred: Experience with cloud-native environments and container technologies, including Docker and Kubernetes.
• Preferred: Experience developing model evaluation frameworks and AI quality measurement systems.
• Preferred: Experience making architectural decisions across multi-service machine learning environments.
• Preferred: Experience balancing model quality, operational cost, scalability, and performance requirements for production AI systems.

Responsibilities:

• Develop, evaluate, and improve machine learning models and algorithms for Content AI applications.
• Design and implement end-to-end machine learning solutions, including data preparation, feature engineering, model training, validation, deployment, monitoring, and continuous optimisation.
• Apply statistical analysis, experimentation, and data-driven decision-making to assess model performance and guide technical direction.
• Collaborate with engineers, product managers, applied scientists, and domain experts to translate ambiguous business problems into scalable ML solutions.
• Contribute to system design, low-level design, API development, and data modelling for production machine learning systems.
• Build and operate production solutions using technologies such as Python, TensorFlow, PyTorch, Redis, Airflow, Docker, Kubernetes, and cloud-native infrastructure.
• Design and deploy scalable batch and real-time ML pipelines supporting customer-facing applications.
• Develop and operationalise LLM applications, RAG systems, and Generative AI capabilities for content understanding, summarisation, classification, and recommendation use cases.
• Build evaluation frameworks and observability solutions to monitor model quality, reliability, latency, drift, and business impact.
• Evaluate trade-offs between model quality, scalability, latency, and infrastructure cost when developing AI-powered products.
• Partner with engineering teams to deploy and scale machine learning systems in production.
• Produce clear technical documentation and share expertise through mentorship, design reviews, and technical leadership.

Technologies:

• AI
• Airflow
• API
• Cloud
• Computer Vision
• Docker
• FastAPI
• Support
• Kubernetes
• LLM
• Machine Learning
• Model Training
• Network
• PyTorch
• Python
• RAG
• Redis
• TensorFlow

More:

We are Expedia Group, a global travel company helping travelers explore the world one journey at a time. Through our consumer brands, B2B network, and travel advertising business, we connect travelers, partners, and advertisers using leading technology powered by data, machine learning, and AI. Our Content AI team works within our Product & Technology Machine Learning Science and Engineering organisation to build machine learning capabilities that improve content-focused products and services across Expedia Group, including content understanding, review intelligence, search relevance, ranking, recommendations, moderation, image-based AI applications, and Generative AI experiences used by millions of travelers worldwide. We offer a supportive environment guided by our five Behaviors, with flexibility, benefits, and support to help our people do their best work. This full-time role is based in London.

last updated 39 week of 2026