Top SIMILARITY-SEARCH GitHub Repositories & Tools (2026)

A lightweight, lightning-fast, in-process vector database

One Postgres for your application data, full-text search, vector retrieval, and aggregations. Home of the pg_search extension.

ArcadeDB Multi-Model Database, one DBMS that supports SQL, Cypher, Gremlin, HTTP/JSON, MongoDB and Redis. ArcadeDB is a conceptual fork of OrientDB, the first Multi-Model DBMS. ArcadeDB supports Vector Embeddings.

vsag is a vector indexing library used for similarity search.

valkey-search is a C++ module which extends valkey with vector search and secondary indexing capabilities. It enables users to index and query data stored in Valkey using complex queries with filters while maintaining high performance and scalability.