Machine Learning Engineer, Search and Answers at Reddit

At Reddit, we operate one of the internet’s largest platforms for open conversation, serving more than 101 million daily active visitors across over 100,000 active communities. Our Search and Answers team builds the systems that surface the most relevant results and recommendations whenever users explore topics on Reddit. We deliver this experience through Reddit Search and Reddit Answers, our generative-AI product, working with the world’s largest corpus of human conversation to highlight the best answers, opinions, and communities.

Key outcomes

• Design and refine retrieval pipelines that combine lexical search tuning with semantic retrieval models to surface the most relevant content at scale.
• Train and iterate on multi-objective ranking models that adapt to diverse search intents and maintain high relevance across millions of daily queries.
• Develop query-understanding systems that leverage state-of-the-art machine-learning models, small language models, and large language models to power generative-AI workflows.
• Apply prompt engineering, fine-tuning, and other advanced generative techniques to enhance Reddit Answers while preserving low latency and high output quality.
• Create relevance-focused features that combine AI/ML insights with user-interface elements to help users evaluate search results.
• Establish robust monitoring, high availability, and low-latency performance across production pipelines while collaborating with product, data-science, and platform teams on long-term technical roadmaps.
• Contribute to technical strategy, architecture decisions, and day-to-day execution for systems that serve one of the largest sites on the internet.

Requirements

• Five to ten or more years of industry experience as a machine-learning engineer.
• Hands-on experience building and productionizing models with PyTorch or TensorFlow.
• Proven work on search, recommender, or query-understanding systems operating at large scale.
• Strong proficiency writing production-quality code that includes testing, evaluation, and monitoring, using object-oriented programming in Python and Golang.
• Experience designing and maintaining APIs with GraphQL, REST, HTTP, Thrift, or gRPC, along with a deep systems-level understanding of large-scale recommendation architectures.
• Practical experience developing applications on large-scale data infrastructure such as Kubeflow, Airflow, BigQuery, and Kafka.
• Professional fluency in English.

Compensation

The base pay range for this position is $185,800 – $322,000 USD. In addition to base salary, the role is eligible for equity in the form of restricted stock units and may be eligible for commission, depending on the specifics of the offer. Reddit provides comprehensive medical, dental, and vision insurance, a 401(k) program with employer match, generous paid time off, and additional wellness and family-planning benefits.

How to apply

We invite you to submit your application through our careers site. A member of our recruiting team will review your materials and contact you if your background aligns with the needs of the role.