Senior Staff Machine Learning Systems Engineer, Indexing & Retrieval Search

Team
The ML Indexing & Retrieval Platform team at Reddit is responsible for building and scaling the core infrastructure that powers machine learning driven recommendations. We design and maintain systems for ML data ingestion, low-latency retrieval services, and end-to-end lifecycle management of data. With a focus on performance, reliability, and scalability, we enable real-time access to high-quality data that supports a wide range of applications, including Content Understanding, Semantic, Lexical retrieval & GenAI applications. 

How You'll Have Impact

You’ll lead the development of next-generation ML Indexing & Retrieval systems, owning the full lifecycle from ideation to production and going beyond incremental improvements to reimagine core platform capabilities. As part of a high-impact, cross-functional team, you’ll solve complex technical challenges to build scalable, reliable platforms that empower developers to efficiently ship critical ML features.

Languages: Go, Java, Python, or any object oriented programming language

Frameworks: Flink, Airflow, Spark for large scale batch & stream processing 

Databases: Familiarity with Vector, Lexical & Key-Value Databases 

Tools: Kubernetes, Docker, AWS, GCP

What You’ll Do

• Lead the technical strategy, architecture, and implementation of Reddit’s next-generation ML Indexing & Retrieval engine, integrating capabilities across lexical and vector indexing, low-latency retrieval, and emerging GenAI applications.
• Partner closely with product engineers across Content Understanding, Search, Feeds, Ads, Growth, and Safety to deliver high-quality experiences.
• Define best practices for observability, reliability, and operational excellence in large-scale distributed systems.
• Mentor and guide engineers in designing scalable infrastructure and adopting robust DevOps and SRE principles.
• Collaborate with infrastructure, and ML teams to ensure the platform evolves to meet the needs of Reddit’s growing user base and diverse content ecosystem.…