zvec

https://github.com/MadBomber/zvec-ruby

Add vector search to your Ruby apps without external services. zvec provides native bindings to Alibaba's high-performance C++ vector database via Rice, supporting HNSW, IVF, and flat indexes with multiple distance metrics. Build semantic search, recommendations, RAG pipelines, and similarity matching with pure Ruby — no HTTP APIs, no infrastructure, no latency overhead.