For developers, who are building real-time data-driven applications, Redis is the preferred, fastest, and most feature-rich cache, data structure server, and document and vector query engine.

A modern replacement for Redis and Memcached

Apache Ignite

Distributed, in-memory key/value store and cache. It can be used as an embedded Go library and a language-independent service.

Create full-fledged APIs for slowly moving datasets without writing a single line of code.

OpenMLDB is an open-source machine learning database that provides a feature platform computing consistent features for training and inference.

Hyrise is a research in-memory database.

GhostDB is a distributed, in-memory, general purpose key-value data store that delivers microsecond performance at any scale.

Grafeo is a pure-Rust, high-performance graph database that can be embedded as a library or run as a standalone database, with optional in-memory or persistent storage. Grafeo supports both LPG and RDF and all major query languages.

High-Performance Java-Native-Persistence. Store and load any Java Object Graph or Subgraphs partially, Relieved of Heavy-weight JPA. Microsecond Response Time. Ultra-High Throughput. Minimum of Latencies. Create Ultra-Fast In-Memory Database Applications & Microservices.

Embeddable and distributed in-memory alternative to Redis.

Tsurugi - next generation RDB for the new era

FlashDB is an embeddable, in-memory key/value database in Go (with Redis like commands and super easy to read)

In-memory event-sourced ACID-transactional distributed object graph engine for .NET Standard

High-Performance Java-Native-Persistence. Store and load any Java Object Graph or Subgraphs partially, Relieved of Heavy-weight JPA. Microsecond Response Time. Ultra-High Throughput. Minimum of Latencies. Create Ultra-Fast In-Memory Database Applications & Microservices.

Apache Ignite 3

Obevo is a database deployment tool that handles enterprise scale schemas and complexity

Ultrafast and lightweight in-process memory database written in F# that supports: transactions, secondary indexes, persistence, and data size larger than RAM.

blazing fast, feature-rich in-memory database written in TypeScript

VectorRAG.Net is a .NET-native high-performance vector database library for semantic search and RAG (Retrieval-Augmented Generation). Core search is based on Random Hyperplane LSH candidate generation with exact rerank by dot/cosine.