Data Scientist III (Large Language Models)

Cognism is the leading provider of European B2B data and sales intelligence. Ambitious businesses of every size use our platform to discover, connect, and engage with qualified decision-makers faster and close more deals. Headquartered in London with global offices, Cognism’s contact data and contextual signals are trusted by thousands of revenue teams to eliminate the guesswork from prospecting.

This can be a remote or hybrid role depending on your location and proximity to one of our local offices.

As a Data Scientist, you will design and implement advanced models, drive innovation through machine learning and AI, and mentor team members. In this high-impact role, your work will directly shape Cognism’s data-driven products and business strategies.

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• Develop Advanced Models – Build and maintain sophisticated statistical and machine learning models that drive business decisions and integrate with enterprise systems.
  
• Lead Innovation – Design and pilot cutting-edge predictive models and algorithms, testing scalability and implementing successful approaches into production environments.
  
• Own Projects End-to-End – Scope, design, implement, and evaluate data science solutions independently, while keeping stakeholders aligned on progress and results.
  
• Drive Business Value – Collaborate with cross-functional teams to identify opportunities where data science can make a measurable impact on customer experience or operational efficiency.
  
• Mentor Team Members – Support and guide junior data scientists by sharing best practices, providing feedback, and contributing to an inclusive, knowledge-sharing culture.
  
• Shape Data Strategy – Work closely with the Data Science Manager to prioritize projects and align outputs with strategic goals.
  

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• Professional Experience – 3+ years in a data science role, with a strong track record of delivering impactful, production-ready solutions on Large Language Models (e.g., multi-agent systems, evaluation frameworks on LLMs models, distillation, small model fine-tuning, knowledge extraction).
  
• Technical Expertise – Proficient in Python, Spark, and machine learning frameworks; strong understanding of statistical modeling and big data processing.
  
• Cloud Proficiency – Experience with AWS tools such as S3, SageMaker Studio, Glue Jobs, and Athena is highly desirable.
  
• Educational Background – PhD preferred in Data Science, NLP, Information Retrieval, Mathematics, or Statistics. A Master’s degree with significant experience will also be considered.
  
• Problem-Solving Ability – Strong analytical mindset with the ability to design practical, scalable solutions to complex problems.
  
• Communication Skills – Comfortable explaining technical concepts to non-technical stakeholders and influencing decisions through data insights.
  
• Collaborative Approach – Proven ability to work effectively in cross-functional teams and agile environments.
  
• Publications – in IR related conferences (e.g., EMNLP, ACL, NAACL, EACL, LREC)
  

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• Python & PySpark – Build, test, and deploy machine learning pipelines using scalable data processing tools.
  
• AWS Ecosystem – Leverage services like SageMaker, S3, Glue, and Athena for data engineering and ML model deployment.
  
• ML Frameworks – Work with tools such as scikit-learn, TensorFlow, or similar libraries to experiment and optimize models.
  
• Version Control – Use Git and CI/CD tools to manage code and streamline development workflows.
  
• Data Visualization – Communicate findings with clarity using tools like matplotlib, seaborn, or business-friendly dashboards.
  
• SQL & Big Data – Write efficient queries to extract insights from large, complex data sets.
  

At Cognism, we’re not just building a company - we’re building an inclusive community of brilliant, diverse people who support, challenge, and inspire each other every day. If you’re looking for a place where your work truly makes an impact, you’re in the right spot!

Our values aren’t just words on a page—they guide how we work, how we treat each other, and how we grow together. They shape our culture, drive our success, and ensure that everyone feels valued, heard, and empowered to do their best work.

We Are Nice! We treat each other with respect and kindness (because life’s too short for anything else).

We Are Collaborative. We’re in this together—great things happen when we work as one.

We Are Solution-Focused. Every challenge is just an opportunity in disguise.

We Are Understanding. We empower and support each other to do our best work.

We Celebrate Individual Contributors. Every role matters, and so do you!

At Cognism, we are committed to fostering an inclusive, diverse, and supportive workplace. Our values—Being Nice, Collaborative, Solution-Focused, and Understanding—guide everything we do, and we celebrate Individual Contributors. We welcome applications from individuals typically underrepresented in tech, so if this role excites you but you’re unsure if you meet every requirement, we encourage you to apply!

• Mid-Senior level

• Full-time

• Engineering and Information Technology
• Industries: Software Development

London, England, United Kingdom