Senior Machine Learning Engineer

Reddit Reddit · Consumer · United States · Remote · Ads Engineering

Senior Machine Learning Engineer at Reddit focused on building and deploying production ML systems for consumer-facing features like recommendations, search, and content understanding. The role involves the full ML lifecycle, from research and modeling to production deployment and monitoring, with a focus on large-scale data and model pipelines, and applied AI/LLM experiences.

What you'd actually do

  1. Design, build, and deploy production-grade machine learning models and systems at scale
  2. Own the full ML lifecycle: from problem definition and feature engineering to training, evaluation, deployment, and monitoring
  3. Build scalable data and model pipelines with strong reliability, observability, and automated retraining
  4. Work with large-scale datasets to improve ranking, recommendations, search relevance, prediction, content/user understanding, and optimization systems.
  5. Research and apply state-of-the-art machine learning and AI techniques, including deep learning, graph & transformers based, and LLM evaluation/alignment

Skills

Required

  • Python
  • Java
  • Go
  • software engineering fundamentals
  • ML Fundamentals
  • PyTorch
  • TensorFlow
  • scalable ML pipelines
  • data processing systems
  • model serving infrastructure
  • cross-functional collaboration
  • measurable metrics improvement

Nice to have

  • recommender systems
  • search/ranking systems
  • advertising/auction systems
  • large-scale representation learning
  • multimodal embedding systems
  • distributed systems
  • large-scale data processing
  • Spark
  • Kafka
  • Ray
  • Airflow
  • BigQuery
  • Redis
  • real-time systems
  • low-latency production environments
  • feature engineering
  • model optimization
  • production monitoring
  • LLM/Gen AI techniques
  • LLM evaluation
  • alignment
  • fine-tuning
  • knowledge distillation
  • RAG/agentic systems
  • productionizing LLM-powered products at scale
  • Advanced degree in Computer Science, Machine Learning, or related quantitative field

What the JD emphasized

  • 3-5+ years of experience building, deploying, and operating machine learning systems in production
  • Experience with LLM/Gen AI techniques, including but not limited to LLM evaluation, alignment, fine-tuning, knowledge distillation, RAG/agentic systems and productionizing LLM-powered products at scale

Other signals

  • large-scale applied machine learning
  • production ML systems
  • end-to-end ML lifecycle
  • LLM-driven experiences