Social media and community platform with large-scale search and recommendation infrastructure. Reddit Engineering has published detailed write-ups on their search and ML infrastructure decisions.
- Website: https://www.reddit.com
- Engineering Blog: https://www.reddit.com/r/RedditEng/
Search & ML Infrastructure
Reddit operates at significant scale — their 2025 vector search evaluation covered workloads of 340M+ vectors (Reddit post embeddings at 384 dimensions). Their engineering culture values open-source software, Go as the primary backend language, and reproducible benchmark-driven decisions.
In 2025, Reddit selected Milvus as their company-wide vector database for ANN search, replacing fragmented solutions (Vertex AI Vector Search, Apache Solr ANN, Facebook FAISS sidecars).
People
- Chris Fournie — Staff Software Engineer; led vector database evaluation