You'll work with NLP, LLMs, PyTorch, Hugging Face, and Python on problems in semantic chunking, information extraction, knowledge graph construction, and retrieval optimisation. You'll join an AI research organisation building the document understanding layer that powers next-generation AI search and reasoning systems.

You will work with Python/C++, Ray, Spark, Flink, Kafka/Beam, and ML frameworks for search/recsys and frontier AI (LLMs, RL, multi-agent orchestration). Your role involves building enterprise superintelligence systems—end-to-end architectures that take ownership of business outcomes—as a founding scientist on a small, senior team.

Microsoft★4.2 (9k)· London

You will work with Large Language Models (LLMs), machine learning, deep learning, reasoning systems, retrieval-augmented generation (RAG), tool orchestration, reinforcement learning, and telemetry analysis. The team develops advanced LLM-based capabilities and AI-powered experiences for Microsoft 365 Copilot, an enterprise productivity flagship. You collaborate with a team of scientists, engineers, and product managers.

You will work with large language models (LLMs), MCP tools, agent/multi-agent systems, evaluation frameworks, A/B testing, causal inference, NLP, and ML. You will develop and optimize LLM-powered conversational experiences for the Rufus shopping assistant, helping customers find products, compare options, and get recommendations. The London-based Rufus Features Science team includes ~150 engineers, designers, and product managers.

Microsoft★4.2 (9k)· London

Works with Python, PyTorch and retrieval technologies including ColBERT, SPLADE, dense/sparse hybrid, RAG and LLM-integrated architectures. Builds state-of-the-art retrieval systems for Microsoft 365 Copilot Search, Chat and Agent experiences, serving millions of enterprise users daily.

The role uses Python, ML, statistics, and LLMs to protect Prolific's platform from fraud by identifying expert participants. As the first data person on the Integrity team, you'll shape the role, collaborate across teams, apply risk modelling or classical ML, turn ambiguous problems into experiments and metrics, and iterate on prototypes to build production solutions.

You will work with Python, classical ML, statistics, LLMs, and agentic techniques (RAG, LLM-as-judge, multi-agent workflows). The role designs and prototypes AI/ML methods to improve human data quality, judgement aggregation, and AI evaluation workflows for Prolific's human data platform.

Amazon★3.5 (56k)· London

As an Applied Science Intern, you will work with machine learning, deep learning, generative AI, large language models, speech technology, robotics, computer vision, optimization, operations research, quantum computing, and formal methods, using Java, C++, or Python. You will design and develop end-to-end systems, working with Amazon scientists to create algorithms and models that are deployed into production.

Thomson Reuters★3.9 (4.3k)· London

You'll work with PyTorch, JAX, HuggingFace Transformers, vLLM, LLM APIs, Ray, Spark, and experiment tracking tools like Weights & Biases and MLflow on Thomson Reuters' Foundational Research division, which develops advanced algorithms and training techniques for Large Language Models including LLM training, post-training techniques for reasoning and workflows, data-centric ML, and evaluation. You'll design and implement scalable systems for training, fine-tuning, and evaluating LLMs while translating cutting-edge research into production implementations.

Boston Consulting Group★4.2 (537)· London

You'll develop testing and evaluation frameworks for generative AI and AI products using Python, PyTorch, and TensorFlow, ensuring they meet responsible AI standards for safety, security, and equity. The Responsible AI team at BCG X—a 3,000-person tech organization within the consulting firm—supports product teams across industries in building trustworthy AI systems throughout the software development lifecycle. The role requires 3-5+ years in responsible AI, 3+ years with generative AI models, and program/project management experience.