closevector-node

Implements hierarchical navigable small world (HNSW) graph-based approximate nearest neighbor search for fast similarity retrieval across vector embeddings. The library constructs a multi-layer navigable graph structure that enables sublinear search complexity (O(log N)) by progressively narrowing the search space through layer-by-layer traversal, avoiding the O(N) cost of brute-force similarity computation across entire datasets.

Provides unified vector database API that works identically in browser environments and Node.js runtime, abstracting platform-specific storage mechanisms (IndexedDB for browsers, file system or memory for Node.js) behind a consistent interface. This enables developers to write vector storage logic once and deploy to both client and server without code duplication or platform-specific branching.

Leverages Cloudflare Workers as the execution environment to distribute vector indexing and search operations across edge locations globally, reducing latency by computing nearest neighbor searches closer to end users. The architecture routes queries to the nearest edge location rather than centralizing all vector operations on a single server, enabling geographic distribution without explicit multi-region deployment complexity.

Provides a pluggable architecture allowing developers to implement custom storage backends beyond the built-in IndexedDB and file system options. The library defines a backend interface that abstracts vector persistence, enabling integration with custom databases, cloud storage services, or specialized vector stores while maintaining the same query API.

Maintains vector indexes in application memory for maximum query performance while providing optional persistence to disk or external storage for durability. The library loads the entire index into RAM on startup, enabling microsecond-level query latency, with background or explicit save operations to persist changes to durable storage without blocking queries.

Provides vector search capabilities optimized for retrieval-augmented generation workflows, enabling applications to find relevant document chunks or passages based on semantic similarity to user queries. The library integrates with embedding models to convert documents and queries into vectors, then uses HNSW search to retrieve the most relevant context for LLM prompts.

Offers open-source, zero-cost vector database functionality with no usage limits or feature restrictions for personal projects, development, and prototyping. The library is freely available under an open-source license, allowing unlimited vector storage and queries without subscription fees or commercial licensing requirements.