Machine Learning Engineer - Agentic AI & Reinforcement Learning

responsibilitiesDesign and develop single-agent and multi-agent systems for complex workflows.Build reasoning, planning, task decomposition, memory, tool-use and agent-collaboration capabilities.Integrate LLMs, vision-language models, retrieval systems and domain-specific tools.Fine-tune and adapt foundation models using supervised learning, preference optimisation and reinforcement learning where appropriate.Develop training environments, reward functions, graders and feedback mechanisms.Build evaluation, guardrail and monitoring approaches for agent reliability.Convert prototypes into production-ready APIs, services and reusable software components.Experience and skillsRequired Degree in computer science, artificial intelligence, machine learning, engineering or a related discipline, or equivalent practical experience.Strong Python programming and software-engineering skills.Experience developing machine-learning, generative AI or LLM applications.Practical experience with PyTorch, JAX

TensorFlow or a similar framework.Understanding of agentic AI concepts such as tool calling, planning, memory and workflow orchestration.Knowledge of reinforcement learning, preference optimisation or sequential decision-making.Experience designing model evaluations and translating research ideas into reliable software.Desirable Experience developing multi-agent systems using LangGraph, AutoGen, smolagents or similar frameworks.Experience with LLM fine-tuning, DPO, GRPO, PPO, RLHF or RLAIF.Experience designing reward functions, graders or agent training environments.Experience with Model Context Protocol and tool integration.Experience deploying open-source language or vision-language models, including distributed training or GPU computing.Experience applying AI to scientific, engineering, energy or geoscience workflows. Why work with us?Competitive salary commensurate with experienceHighly attractive bonus schemeInitial 22 days annual leave with future increases, complemented by a flexible buying and selling holiday programHybrid working with two days at home, flexible workingCompany pension with generous employer contributionWellbeing Unmind app - puts you in control of your mental healthA flexible benefits platform with numerous discount schemes - gym membership, restaurants, cinema tickets, and much more!Cycle purchase schemeFlexible Private Medical & Dental care programmesBank Holiday Swap - our holiday swap program allows you to change it for another day of your choice!Buy & Sell Holiday Programme - you can buy extra holiday, sell unused holiday or even save it up!Relaxed dress code policyLearning and DevelopmentAt Viridien, we foster a culture of continuous learning and provide tailored training programs through our Learning Hub, designed to enhance technical, commercial, and personal growth.We Care about the EnvironmentWe encourage and actively support a strong sense of community, through volunteering and various company initiatives, as well as a strong company commitment to protecting our environment through sustainable solutions, energy saving and waste reduction enterprises.Our Hiring ProcessAt Viridien, we are committed to delivering a respectful, inclusive, and transparent recruitment experience.Due to the high volume of applications we receive, we may not be able to provide individual feedback to every applicant. Only candidates whose qualifications closely match the role criteria will be contacted for an interview. We do, however, aim to share personalized feedback with those who progress to the first round of interviews and beyond.We are also dedicated to ensuring that our hiring process accessible to all. If you require any reasonable adjustments to fully participate in the application or interview stages, please don’t hesitate to contact your recruiter directly.We see things differently. Diversity fuels our innovation, we value the unique ways in which we differ, and we are committed to equal employment opportunities for all professionals.SummaryLocation: Crawley, United KingdomType: Full time