Machine Learning Engineer, Apple Search & Platforms

Staff Machine Learning Engineer, Apple Search & Knowledge Platforms

Santa Clara, California, United States Machine Learning and AI

The AI, Search & Knowledge Platforms team builds amazing products and services for Apple’s customers while serving as a foundational partner to teams across Apple. The team delivers world‑class AI, search, and knowledge systems powering Siri, Apple Intelligence, Safari, and iMessage, and operates the foundational platforms and infrastructure that keep these intelligent experiences running  part of this group, you will be doing large‑scale machine‑learning and deep‑learning research and development to improve Open Domain Question Answering (using both structured knowledge‑graph data and unstructured web data) and Summarization, as well as developing fundamental building blocks needed for Artificial Intelligence.

This involves developing sophisticated machine learning and large language models (LLMs) to understand user queries, retrieve and rank relevant documents across multiple sources, and synthesize information across documents to provide the user with a direct answer that best satisfies their intent and information‑seeking needs. Additionally, you will research and develop state‑of‑the‑art LLMs for summarizing personal data such as emails, messages, and notifications.

You will also work with researchers and data scientists to develop, fine‑tune, and evaluate domain‑specific Large Language Models for various tasks and applications in Apple’s AI‑powered products and conduct applied research to transfer cutting‑edge research in generative AI to production‑ready technologies.

In this role, you will work on LLM‑based question answering and Apple Intelligence features to provide concise, accurate, and grounded information to users to help them complete their tasks quickly on Apple devices.

• Designing and developing advanced Reinforcement Learning technologies in the post‑training of generative models, and delivering the end‑user experience.
• Driving cross‑functional technical initiatives, collaborating with research, engineering and production teams to translate theoretical advances into deployable systems.
• Developing novel and cutting‑edge RL algorithms and improving existing ones.
• Staying up to date with the latest RL research and integrating best practices into the team’s workflow.
• Working on the end‑to‑end ML lifecycle: algorithm design and implementation, data collection, model training, evaluation, and deployment.

• 10+ years of ML experience in search, natural language processing/understanding, and conversational AI.
• Proven experience with LLM post‑training, including but not limited to SFT, RLHF, RLAIF, reward modeling, chain‑of‑thought, and agentic LLM.
• Hands‑on experience building RL pipelines and training agents in simulation or real‑world environments.
• Growth mindset and ability to learn new technologies.
• MS or Ph.D. in Computer Science, Machine Learning with a specialty in reinforcement learning, or a related field.

• Deep expertise in reinforcement learning‑based post‑training on LLM models, reward modeling, RLHF, RLAIF, chain‑of‑thought, and agentic AI R&D.
• Deep understanding of cutting‑edge RL algorithms and large language models.
• Strong product intuition and ownership.

At Apple, base pay is one part of our total compensation package and is determined within a range. The base pay range for this role is between $212,000 and $386,300, and your base pay will depend on your skills, qualifications, experience, and location.

Apple employees also have the opportunity to become an Apple shareholder through participation in Apple’s discretionary employee stock programs. Apple employees are eligible for discretionary restricted stock unit awards, and can purchase Apple stock at a discount if voluntarily participating in Apple’s Employee Stock Purchase Plan. You’ll also receive benefits including comprehensive medical and dental coverage, retirement benefits, a range of discounted products and free services, and reimbursement for certain educational expenses—such as tuition—for formal education related to advancing your…