Senior ML Infrastructure Engineer — Large-Scale Personalization

Reddit; United States; Remote; USD 180,000 - 240,000; Full time

Job summary

Reddit is seeking a Senior Machine Learning Infrastructure Engineer to work across model development and ML platform, building large-scale learning systems that power personalization and recommendations.

You will own major technical components end to end, design training and evaluation pipelines, drive production deployment, and collaborate with ML platform, product, and cross-functional teams to deliver measurable user and business impact.

Qualifications

• 5+ years of experience in machine learning engineering, focusing on large-scale ML infrastructure and recommendation/personalization systems.
• Expertise in modern deep learning architectures, including sequence models and foundational models.
• Experience building or scaling ML platform for large datasets and high-traffic production environments.
• Demonstrated ability to independently scope and execute ambiguous technical work while owning high-quality implementation details.
• Solid understanding of distributed training.

Responsibilities

• Design, train, and improve large-scale machine learning platforms for recommendation or personalization systems.
• Own and deliver major ML systems components end to end, from problem framing through production rollout.
• Build and optimize end-to-end ML pipelines spanning data preparation, feature generation, training, evaluation, and deployment.
• Improve distributed training, model efficiency, and online inference performance.
• Apply modern modeling approaches including sequence modeling and related foundation-model techniques to Reddit use cases.
• Develop reliable serving and monitoring patterns for low-latency, high-throughput production ML systems.
• Work with cross-functional partners across product, relevance, ads, and core ML teams to deliver measurable improvements in user experience and business impact.
• Drive rigorous offline and online evaluation, including experimentation, model diagnostics, and feedback-loop improvement.
• Contribute to engineering quality through strong code, design reviews, documentation, and operational excellence.

Skills

Large-scale ML platforms

Sequence modeling

Foundational models

Distributed training

Production ML systems

Job description

Reddit is seeking a Senior Machine Learning Infrastructure Engineer to work across model development and ML platform, building large-scale learning systems that power personalization and recommendations.

You will own major technical components end to end, design training and evaluation pipelines, drive production deployment, and collaborate with ML platform, product, and cross-functional teams to deliver measurable user and business impact.