Flexible Work, Better Balance
London, England, United Kingdom Corporate Functions
At Apple, we build AI systems that define experiences for billions of people and we do it with an unwavering commitment to privacy, performance, and craft. The AI & Data Platforms (AiDP) team is seeking a Principlal Machine Learning Engineer to lead the design, fine‑tuning, evaluation, and productionisation of large language models and generative internal AI systems at global scale. This is a deeply hands‑on, high‑impact role: you will work across the full model lifecycle, from reinforcement learning and upstream training through to deployment of standalone, customer‑facing products. The ideal candidate is equal parts researcher, engineer, and product builder. You bring authoritative depth in LLM customisation and alignment, a sharp instinct for performance and quality, and the ability to ship end‑to‑end AI‑powered products that meet Apple's standa...