Weaviate is an open-source vector database that stores objects and vectors. Developers use it for semantic search, keyword filtering, RAG and reranking. The core is written in Go; client libraries exist for Python, JavaScript/TypeScript, Java, Go and C#, and the database exposes REST, gRPC and GraphQL APIs. The company describes Weaviate as a platform for vector search, RAG and memory, including a Query Agent and embeddings. You can run it yourself with Docker or Kubernetes, or use the managed service Weaviate Cloud.
Weaviate B.V. is based in Amsterdam. The core is largely licensed under BSD-3-Clause; one folder is available only under a commercial licence, and enterprise features require a licence key. According to its documentation, Weaviate Cloud runs on AWS or GCP; the documentation does not list the available regions, so check when creating a cluster whether a European region is offered. Self-hosting on your own infrastructure keeps the data entirely under your control.