Senior Prompt Engineer - AI - Full-time Berkshire, New York, United States · Full Time Posted 2026-09-10 📌 Job Title: Senior Prompt Engineer - AI - Full-time📍 Location: Berkshire, UK🕐 Employment type: Full-time🌍 Environment: AI Environment About the Role We are seeking a Senior Prompt Engineer to lead the design, optimization, and scaling of advanced prompting strategies for large language models (LLMs). This role is pivotal in delivering context-aware, safe, and efficient AI outputs across complex enterprise use cases. You will collaborate closely with engineering teams to integrate prompts into application workflows, autonomous agents, and RAG pipelines, continuously improving performance, reducing latency, and ensuring output consistency. Key Responsibilities Design and implement advanced, dynamic prompts tailored to business-specific use cases. Optimize LLM performance by reducing token consumption, latency, and hallucinations. Integrate prompts into agent-based systems, APIs, and RAG architectures. Develop prompt frameworks and reusable templates for scalable deployment. Establish evaluation, benchmarking, and regression testing mechanisms. Implement guardrails to mitigate prompt injection and unsafe outputs. Collaborate with product and engineering teams to translate business requirements into technical prompt logic. Maintain a version-controlled prompt repository with continuous improvements. Your Profile 5+ years in software engineering with 2+ years in production-level prompt engineering. Strong expertise in LLMs: GPT-4, Claude, Llama, Mistral, Nova (or similar). Advanced programming skills in Python and/or Java. Experience with AI orchestration frameworks such as LangChain and LlamaIndex. Hands-on experience with prompt evaluation and monitoring tools, such as LangSmith, Fiddler, InspectAI, and OpenAI Evals. What's Offered Competitive salary of £55,000–£60,000. Permanent position with equity partnership in the business. Flexible, hybrid working environment based in the UK. Opportunity to work on cutting-edge AI technologies. Ideal Candidate The ideal candidate is a seasoned professional with a passion for AI and prompt engineering. You possess a strong technical background, particularly in LLMs and Python, and have a proven track record of integrating AI solutions into complex systems. You are eager to collaborate with cross-functional teams and are committed to delivering high-quality, efficient AI outputs. If you are ready to take on a challenging and rewarding role, we would love to hear from you. When you apply to this role, AI may be used to help analyse and format your information so the hiring team can review it more easily. Frequently asked questionsHow do I apply for the Senior Prompt Engineer - AI - Full-time role?You can apply directly on this page — submit your CV and contact details through the application form, no account required.