Principal Data Scientist

Are you a hands‑on data scientist with deep expertise in NLP and LLMs, strong Python coding skills, and a track record of deploying models to production? Do you thrive in building real‑world AI solutions that are used by actual customers? If so, we’d love to talk to you! As a Principal Data Scientist (individual contributor), you will play a hands‑on role in designing, building, and deploying scalable AI solutions that go beyond prototypes and are actively used in production. You’ll work closely with collaborative teams to co‑develop innovative products for financial markets and professionals. We’re looking for someone who combines deep technical expertise in NLP and LLMs, strong Python engineering skills, and real‑world experience shipping and supporting models in production. You should be comfortable owning delivery timelines and ensuring that solutions meet business needs and production‑grade standards. This is a hands‑on technical leadership role in a high‑impact environment focused on delivering production‑ready AI systems.

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• Lead the end‑to‑end development of AI solutions: design, build, test, and deploy models that are robust, scalable, and used by real users.
  
• Apply NLP and LLM techniques to solve real‑world problems, ensuring models are optimized for performance and reliability.
  
• Continuously improve model quality through tuning, evaluation, and feedback from production usage.
  
• Evaluate third‑party AI solutions with a critical eye on performance, scalability, and integration into production environments.
  
• Write and maintain production‑grade Python code, adhering to best practices in software engineering and model development.
  
• Collaborate with engineering and business partners to define requirements, shape roadmaps, and ensure successful delivery of AI products.
  

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• Strong Python programming skills, including object‑oriented design and proficiency with key ML libraries (e.g., PyTorch, TensorFlow, Scikit‑Learn).
  
• Solid understanding of probability and statistical modeling to support robust model development and interpretation.
  
• Experience with cloud platforms (especially Azure and/or AWS) and modern deployment practices for scalable AI delivery.
  
• Proven ability to set and uphold coding and model evaluation standards for production environments.
  
• Excellent communication skills to articulate technical decisions and trade‑offs to both technical and non‑technical audiences.
  
• Familiarity with DevOps practices including CI/CD, version control, automated testing, and monitoring to support reliable model deployment and maintenance.
  
• Bachelor’s degree in Engineering, Computer Science, Data Science, Statistics, Mathematics, Physics or a related field, or equivalent practical experience.
  

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• High‑impact projects: Work on innovative AI products that solve complex, high‑value challenges using rich datasets.
  
• Competitive benefits: Strong compensation, comprehensive benefits, and investment in your career growth.
  
• Industry leadership: Be a founding member of a team delivering novel products that democratize modeling and analytics.
  
• Collaborative environment: Join a team of experienced engineers in a culture of continuous learning and development.
  

LSEG is a leading global financial markets infrastructure and data provider. Our purpose is to drive financial stability, empower economies, and enable customers to create sustainable growth. We value Integrity, Partnership, Excellence, and Change. We are committed to diversity and inclusion and are an equal opportunities employer. We offer an inclusive, flexible work environment with the possibility of digital‑first with at least one day in office. The role culture includes empathy, collaboration, and continuous improvement.

We recognize the importance of flexibility and are open to discussing work arrangements. This role is considered ‘digital first’, requiring at least one day per week in the office, with additional in‑person collaboration as needed. If you’re ready to take your career to the next level, we’d love to hear from you.

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