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Staff Machine Learning Engineer, AI Security

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Company

Reddit

Location

Remote - United States

Status

Open

Posted

2026-09-15T06:07:12+00:00

Reddit's AI Security team seeks a founding Staff Machine Learning Engineer to build models that detect prompt injection, jailbreaks, sensitive data exposure, and unsafe AI behavior, extending Reddit's LLM Guardrails Platform. The role is a hands-on individual contributor position with technical leadership and a multi-quarter modeling roadmap. Work includes selecting and fine-tuning pretrained models and classifiers, building reproducible training and evaluation pipelines, and owning training-data quality and the production model lifecycle. It asks for 8+ years of ML experience, Python, deep learning frameworks, and distributed training.