Redis

Redis is an open-source, in-memory database that stores data in memory instead of on a disk or solid-state drive (SSD). It's used as a:
Distributed, in-memory key–value database
Cache
Message broker
Vector database
Document database
Streaming engine
Redis is built to deliver speed, reliability, and performance. It offers:
Built-in replication capabilities
Support for complex data types, including strings, hashes, lists, sets, sorted sets, and JSON
Atomic operations defined on data types
Retrieval-augmented generation (RAG) workflows and similarity searches
Support for integrations and diverse data types