Machine Learning Engineer, Answers Relevance
Core
Senior ML Engineer leading production systems for Reddit Answers to surface relevant human-generated conversations using AI.
Role type
Senior IC machine learning engineer (retrieval & LLM)
Builds
Large-scale retrieval, ranking, embeddings, and LLM-powered features for the Answers product
Domain
Social media, conversational AI, RAG, and large-scale ML infrastructure
Deliverable
production ML models
Required skills
TensorFlow, PyTorch, Hugging Face Transformers, Python, Golang, data pipelines, feature engineering, model training and serving, production monitoring
Preferred skills
Agentic AI, tool calls, MCPs, multi-agent systems, self-hosted open-weight models (Qwen, Llama), prompt engineering, fine-tuning, post-training, prompt optimization, latency optimization, caching, cost scaling, safety measures for prompt injection
Technologies
TensorFlow, PyTorch, Hugging Face Transformers, Qwen, Llama
Responsibilities
Build and improve large-scale ML systems including retrieval and ranking; Set technical direction and deliver measurable user and business impact; Work with partner teams to shape product and technical roadmaps; Evaluate new AI/ML approaches and support responsible LLM development; Mentor engineers and contribute to long-term ML planning
Seniority
Senior, hands-on IC
