Reddit is a community of communities. It’s built on shared interests, passion, and trust, and is home to the most open and authentic conversations on the internet. Every day, Reddit users submit, vote, and comment on the topics they care most about. With 100,000+ active communities and approximately 130 million daily active unique visitors, Reddit is one of the internet’s largest sources of information. For more information, visit www.redditinc.com.
🏢 About Reddit
At Reddit, machine learning sits at the heart of how millions of people discover, connect, and engage with the world’s largest collection of human conversations. From “How do I fix a leaky faucet?” to “What should I watch next?”, the Answers Relevance team leverages AI to connect people with the real-world wisdom of Reddit communities. We’re hiring Senior and Staff Machine Learning Engineers to make Answers smarter, more relevant, and more helpful. Our SOTA AI systems helps surface the right conversations, but the heart of Answers is still people helping people ~ Redditors sharing what they know with each other!
🎯 The Role
You’ll lead ML projects from idea to production, partnering with Product, Data Science, and Engineering across recommendations, search, messaging, and AI systems.
✅ Key Responsibilities
Build and improve large-scale ML systems, including retrieval and ranking, embeddings, and LLM-powered features
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
📌 Required Qualifications
4–12 years of experience building, deploying, and operating ML systems in production
Broad knowledge of ML fundamentals and experience applying them in production; expert-level modeling depth isn’t required
Experience developing and productionizing models with TensorFlow, PyTorch, or Hugging Face Transformers
Experience writing production-quality code, including testing, evaluation, and monitoring; Python experience required, Golang experience a plus
Experience with ML systems such as data pipelines, feature engineering, model training and serving, and production monitoring
Strong communication and collaboration skills, and a record of delivering measurable product impact
⭐ Desirable Experience
Recommendations, search, content understanding, or large-scale data and ML infrastructure
SOTA large scale RecSys
Foundational retriever models
RAG systems, retrieval methods, LLM evaluation, or production LLM features
Agentic AI, such as tool calls, MCPs, multi-agent systems, or orchestration
Self-hosted open-weight models such as Qwen or Llama; prompt engineering, fine-tuning, post-training, or prompt optimization
Improving grounding, instruction following, and hallucination; evaluating retrieval and generation quality
Scaling LLM systems, including latency, caching, and cost; safety measures for prompt injection and unsafe inputs
Defining product success metrics, feedback loops, and evaluation approaches, including human review
🎁 Benefits
Comprehensive Healthcare Benefits and Income Replacement Programs
401k with Employer Match
Global Benefit programs that fit your lifestyle, from workspace to professional development to caregiving support
Family Planning Support
Gender-Affirming Care
Mental Health & Coaching Benefits
Flexible Vacation & Paid Volunteer Time Off
Generous Paid Parental Leave
🛂 Visa & Eligibility
Reddit is proud to be an equal opportunity employer, and is committed to building a workforce representative of the diverse communities we serve. Reddit is committed to providing reasonable accommodations for qualified individuals with disabilities and disabled veterans in our job application procedures. If, due to a disability, you need an accommodation during the interview process, please let your recruiter know.