A curated list of awesome vector search framework/engine, library, cloud service and research papers to vector similarity search

• Apache Cassandra 5.0 – Vector search (cep-30), Strict Serialisable ACID (cep-15), horizontally scaling database
• Qdrant - Vector Similarity Search Engine with extended filtering support
• Vald - A Highly Scalable Distributed Vector Search Engine
• Milvus - A cloud-native vector database with high-performance and high scalability.
• Weaviate - A cloud-native, real-time vector search engine
• OpenDistro Elasticsearch KNN - A machine learning plugin which supports an approximate k-NN search algorithm for Open Distro for Elasticsearch
• Elastiknn - Elasticsearch plugin for nearest neighbor search
• Epsilla - A High Performance Vector Database Management System, Hippocampus For AI
• Vearch - A scalable distributed system for efficient similarity search of deep learning vectors
• pgANN - Fast Approximate Nearest Neighbor (ANN) searches with a PostgreSQL database
• Jina - Jina allows you to build deep learning-powered search-as-a-service.
• Infinity - The AI-native database built for LLM applications, providing incredibly fast vector and full-text search
• Aquila DB - Distribution focused k-NN search algorithm
• Redis HNSW - A redis module for similarity search based on HNSW
• Solr - Apache Solr - has a Dense Vector Search feature as of Solr 9.0
• Marqo - A semantic search engine which supports tensor search (sequence of vectors)
• txtai - Build semantic search applications and workflows
• Semantra - A multipurpose tool for semantically searching documents.
• SuperDuperDB - Bring AI to your favorite database
• TensorDB - High Performance Vector Database Supporting Heterogeneous Computing
• JVector - a pure Java, zero dependency, embedded vector search engine, used by DataStax Astra DB and Apache Cassandra.
• VQLite - Simple and Lightweight Vector Search Engine
• Vexvault - 100% browser based, open source, scalable, simple, zero-cost vector search
• Vespa.ai - Text search engine and ... fast approximate vector search (ANN)
• Vespa's large-scale ANN search using HNSW-IF indexes is described here

• LangStream - LangStream is an open-source project that combines the best of event-based architectures with the latest Gen AI technologies.
• CassIO - CassIO is the ultimate solution for seamlessly integrating Apache Cassandra® with generative artificial intelligence and other machine learning workloads
• JVector - A pure Java, zero dependency, embedded vector search engine used by some of the advanced distributed databases such as DataStax Astra DB & Apache Cassandra™
• Faiss - A library for efficient similarity search and clustering of dense vectors
• Distributed Faiss - Work with FAISS indexes which don't fit into a single server memory
• Autofaiss - Automatically create Faiss knn indices
• ScaNN - A library efficient vector similarity search at scale.
• NMSLIB - Non-Metric Space Library, an efficient similarity search library for generic non-metric spaces
• Annoy - C++ library with Python bindings to search for points
• FLANN - Library written in C++ and contains bindings for the following languages: C, MATLAB, Python, and Ruby
• LLM App - Open-source Python library for a real-time data KNN (K-Nearest Neighbors) indexing
• MRPT - Fast nearest neighbor search with random projection
• RPForest - Python library for approximate nearest neighbours search
• pgvector - Open-source vector similarity search extension for Postgres
• PASE - Ultra-High-Dimensional approximate nearest neighbor search extension for Postgres
• Pyserini - Toolkit for reproducible information retrieval research with sparse and dense representations
• NGT - Provides commands and a library for performing high-speed approximate nearest neighbor
• NearPy - Approximate search using different locality-sensitive hashing methods
• TOROS N2 - lightweight approximate Nearest Neighbor library
• PUFFINN - Parameterless and Universal Fast FInding of Nearest Neighbors
• SPTAG - A distributed approximate nearest neighborhood search (ANN) library
• PyNNDescent - A python nearest neighbor descent for approximate k nearest neighbors
• TarsosLSH - A Java library implementing practical nearest neighbour search algorithm for multidimensional vectors
• TorchPQ - Efficient implementations of Product Quantization and its variants using Pytorch and CUDA
• Granne - Graph-based retrieval of approximate nearest neighbors witten in rust
• Embeddinghub - A database built for machine learning embeddings
• Hora - Efficient approximate nearest neighbor search algorithm collections library written in Rust
• Voy - A WASM vector similarity search engine written in Rust
• Chroma - The open-source embedding database for building LLM apps in Python or JavaScript with memory
• USearch - Smaller & Faster Vector Search Engine for C++, Python, JavaScript, Rust, Java, GoLang, Wolfram
• Golang vector stores collection - Chroma, PGVector interfaces
• Scalable Vector Search (SVS) - A performance library for vector similarity search

• Epsilla Cloud - The fully managed serverless vector database with 10X faster, cheaper and better.
• DataStax Astra Vector - Multi-cloud, serverless vector DBaaS
• Relevance AI - Vector Platform From Experimentation To Deployment
• Pinecone - Managed vector search with filtering, live index updates, horizontal scaling, and a lot more
• MyScale - A managed vector database based on ClickHouse
• Redis Cloud - Managed vector database in Redis
• Zilliz Cloud - Cloud-native service for Milvus

List of methods on how approximate vector search algorithm can be implemented more effciently.

• SPANN: Highly-efficient Billion-scale Approximate Nearest Neighborhood Search - NEURIPS 2021
• Revisiting the Inverted Indices for Billion-Scale Approximate Nearest Neighbors - ECCV 2018
• Accelerating Large-Scale Inference with Anisotropic Vector Quantization
• Billion-scale similarity search with GPUs
• Efficient and robust approximate nearest neighbor search using Hierarchical Navigable Small World graphs
• Optimization of Indexing Based on k-Nearest Neighbor Graph for Proximity Search in High-dimensional Data
• On Approximately Searching for Similar Word Embeddings - ACL 2016