LanceDB

LanceDB is an open-source vector database that embeds directly inside your application and is built on the Lance columnar format for fast similarity search across large multimodal datasets. It's aimed at AI/ML developers and engineering teams building retrieval, RAG, and agent-memory systems who want low-latency, billion-scale vector search without running a separate managed service. Its main differentiator is the disk-based Lance format, which keeps storage costs down and enables random-access reads over huge multimodal (text, image, video) datasets rather than holding everything in memory.