Machine Learning Engineer - iCloud Anti-Abuse

Apples iCloud Anti-Abuse team protects hundreds of millions of users from spam, phishing, and malicious content across Mail, Calendar, and Contacts.

We are looking for an ML engineer who can build and ship models in production distributed systems. You will design, train, and deploy ML models that operate at iCloud scale, working across the full lifecycle from data pipelines to real-time inference. You will partner with backend engineers and cross-functional teams in trust and safety, operations, and product to deliver measurable improvements in user protection.

This role sits at the intersection of machine learning and distributed systems engineering. You will play a foundational role in building the teams ML capabilities - owning ML-driven abuse detection: building features from high-volume data streams, training and evaluating classification and ranking models, deploying them into low-latency serving infrastructure, and closing the feedback loop. The systems you build will run at massive scale across Apples infrastructure.

Success in this role means writing production-quality code, reasoning about distributed system tradeoffs, and iterating quickly on model performance. This is a high-impact role - your work will directly determine whether abuse reaches iCloud users or gets stopped.

Own the end-to-end ML lifecycle for abuse detection across Mail, Calendar, and Contacts: data pipelines, feature engineering, model training, deployment, and monitoring

Build and maintain ML infrastructure that operates reliably at iCloud scale with low-latency, high-availability requirements

Develop techniques to identify and score abusive actors and patterns at scale

Analyze model performance, identify failure modes, and drive continuous improvement

Partner with backend engineers and cross-functional teams in trust and safety, operations, and product

3+ years of hands-on machine learning engineering experience, including training and deploying models in production

Strong programming skills in one or more production languages (e.g., Java, Scala, Kotlin, Go, Python)

Experience building and operating ML pipelines: data processing, feature engineering, training, serving, and monitoring

Solid foundation in distributed systems - you can reason about scalability, fault tolerance, and latency tradeoffs

Familiarity with classification, ranking, or anomaly detection techniques

Ability to drive projects independently from problem definition to production

BS in Computer Science, Machine Learning, or a related technical field, or equivalent practical experience

5+ years of ML engineering experience (or equivalent depth) with models running at scale in production

Experience with abuse detection, fraud prevention, content filtering, or trust and safety systems

Expertise in NLP or text classification applied to email, messaging, or similar domains

Experience with streaming/real-time ML inference in addition to batch processing

Familiarity with techniques for scoring, ranking, or classifying actors and behaviors at scale

Understanding of privacy-preserving ML techniques and responsible data handling

Experience with email protocols (SMTP, IMAP) or messaging infrastructure

MS/PhD in Computer Science, Machine Learning, or a related technical field, or equivalent practical experience