Location
London (Remote-friendly with option to join on-site as desired or required)

Hours
Flexible schedule to suit your lifestyle, promoting work-life balance

Salary
Negotiable, competitive compensation packages including base salary and annual bonuses

About the Role
As a Senior Machine Learning Scientist at Tripadvisor, you will join the Experiences R&D Team, evolving the world’s leading marketplace for travel experiences. You will serve as a key technical lead and pod architect within our core discovery engine, independently owning and executing the machine learning strategy for major product capabilities such as Search, Retrieval, Ranking, or Content AI. This role bridges state-of-the-art research and production-grade engineering, requiring you to navigate technical ambiguity, implement custom algorithmic components, and map offline model metrics directly to business KPIs like booking conversion and user engagement. You will lead rapid prototyping, practical deployment of SOTA models, and multiply the capabilities of your peers through mentorship and collaboration. Your work will directly impact how millions of users discover and plan their travel itineraries, making memorable travel experiences more accessible than ever.

What You’ll Do
- Act as technical lead for ML projects within your pod, designing and implementing custom model components and loss functions
- Evaluate new architectures balancing model complexity, inference speed, memory usage, and execution costs
- Optimize models for production using quantization, distillation, and other techniques
- Develop rigorous validation automation to prevent data leakage, over-fitting, and production regressions
- Collaborate with Engineering Leads to ensure infrastructure supports model requirements and build robust fallback systems
- Diagnose complex algorithmic bugs and implement automated checks for silent failures
- Lead post-mortems and corrective actions
- Mentor mid-level and associate ML scientists, ensuring scientific rigor and guiding production constraints

What We Offer
Competitive compensation routinely benchmarked against industry data, flexible and remote-friendly work environment, donation matching, tuition assistance, lifestyle benefits, travel perks, employee assistance programs, health benefits, and a generous referral scheme. We foster a culture focused on traveler-first values, agile execution, and collaborative success.

Experience
5+ years of industry experience developing, validating, and deploying large-scale ML models in production environments.

About you
Relentlessly curious scientist with strong practical and theoretical foundation in machine learning, feature engineering, and deep learning paradigms. Proven ability to adapt and hybridize state-of-the-art architectures to solve complex business problems. Skilled in rapid prototyping, practical SOTA deployment, and mentoring peers. Comfortable navigating technical ambiguity and driving projects to completion.

Qualifications
Master’s or Ph.D. degree in Computer Science, Machine Learning, Statistics, or a highly quantitative field.

Technical Skills
- Mastery of Python and deep learning frameworks such as PyTorch, PyTorch Lightning, or TensorFlow
- Familiarity with data versioning and experiment tracking tools
- Experience with next-generation retrieval pipelines, multi-stage ranking systems, and Content AI stacks
- Knowledge of advanced sequential recommendation systems modeling real-time user session dynamics
- Experience with Graph Neural Networks (GNNs), knowledge graphs, and multi-modal representation learning
- Exposure to Generative AI and Agentic AI workflows to enhance conversational discovery experiences