Machine Learning Jobs in York

CureAge Therapeutics · London

Lead the computationally guided design of a lipid nanoparticle delivery platform, applying chemical and biophysical principles to optimise LNP composition and formulation. Use AI-enabled chemistry, cheminformatics, predictive models and molecular modelling to prioritise formulation components, working closely with the experimental team and founding team in a small start-up.

Hadean · London

Lead a new AI-powered defence product team, line-managing AI/ML, simulation, infrastructure and web engineers while staying hands-on in TypeScript, React and Node. You own delivery end-to-end, hiring and people development, partnering with Product and technical leads, with hybrid working one day a week in Shoreditch.

Cohere · London

Optimises large language model training performance, focusing on throughput and accelerator utilisation. Writes low-level CUDA and Triton kernels, works on distributed training strategies, and builds profiling tools within the Pre-Training team. Combines software engineering, ML and kernel design to remove performance bottlenecks.

Cohere · London

Post-train frontier AI models to state-of-the-art performance, writing high-performance scalable training software and improving SFT and RL cycles. Works across research and engineering on large-scale distributed training with Python, JAX, PyTorch, Kubernetes, Slurm and Ray, coordinating with specialist teams such as Agentic and Code.

Quantexa · London

Builds and shapes next-generation data analytics products within the R&D team, working on the core Contextual Decision Intelligence platform used for fraud, financial crime and data management. Back-end services are written in Scala as microservices, using Cats, Shapeless, Akka and Monix, with event sourcing and CQRS in the persistence layer.

OpenAI · London

Builds and scales the infrastructure that trains and deploys OpenAI's agentic models, spanning a novel in-house container orchestration platform, FastAPI and gRPC APIs, and Terraform-managed cloud systems. Works closely with researchers on novel training runs while scaling production agent platforms to hundreds of millions of users.

Cohere · London

Hands-on research and engineering role on the Agent Code team, developing code-generating LLMs and autonomous agent systems for enterprise use. Involves training code models, building agent frameworks for inference and sampling, creating SFT trajectories, working on RL algorithms, and designing benchmarks, in collaboration with the pretraining team on frontier compute infrastructure.

Cohere · London

Drive safety research for agentic LLMs, focusing on data generation, post-training algorithms and evaluation methods so models that access external tools and act in the world remain fair, trustworthy and secure. Work with cross-functional ML, data annotation, product and policy teams on a small, autonomous team, requiring strong statistics, software engineering and Python/PyTorch skills.

Cohere · London

Own end-to-end technical program delivery for UK public sector and defence customers, from initial deployment through production scaling, acting as the bridge between frontier AI capabilities and government requirements. Navigate procurement, security authorisations, data sovereignty and compliance while coordinating Applied ML, Forward Deployed Engineering, Platform and Product teams. Work spans air-gapped, on-premises and highly regulated environments.

Cohere · London

Owns the evaluation strategy for an enterprise AI workspace, building evals that capture agentic workflows, tool use and knowledge work. Translates user feedback, production failures and usage logs into continuous measurement, then feeds model failures and capability gaps back to central modelling teams. Sits between product, customer-facing and research teams rather than being pure research or product engineering.

Cohere · London

Builds reinforcement learning environments for enterprise AI agents, populating them with hard tasks, plausible data and reward verifiers, then runs agents inside to evaluate and train them. Works across modelling and product to find capability gaps, and partners with external vendors on expert-built environments and quality tooling.

Cohere · London

Forward deployed engineer building and shipping LLM-powered agentic workflows for enterprise customers, from early prototypes to production-grade agents. Works directly with clients in finance, healthcare and telecoms, integrating models with tools, APIs and sensitive data, and contributing features to Cohere's North AI workspace platform.

Cohere · London

Designs next-generation evaluation benchmarks and infrastructure to measure LLM progress, including training LLM judges, refining data synthesis pipelines, and improving evaluation efficiency. Works cross-functionally to turn model feedback into trustworthy, repeatable evaluations, and builds scalable tools for probing model performance.