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.

FoundationDB - the open source, distributed, transactional key-value store

A flexible distributed key-value database that is optimized for caching and other realtime workloads.

Infinispan is an open source data grid platform and highly scalable NoSQL cloud data store.

Fast persistent recoverable log and key-value store + cache, in C# and C++.

A course of building an LSM-Tree storage engine (database) in a week.

✔️ Secure, simple key-value storage for Android

Apache Pegasus - A horizontally scalable, strongly consistent and high-performance key-value store

Python disk-backed cache (Django-compatible). Faster than Redis and Memcached. Pure-Python.

Rust Client for TiKV.

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

A fast, log structured key-value store.

The PebblesDB write-optimized key-value store (SOSP 17)

Embedded key-value store for read-heavy workloads written in Go

Skytable is a modern scalable NoSQL database with BlueQL, designed for performance, scalability and flexibility. Skytable gives you spaces, models, data types, complex collections and more to build powerful experiences

A RocksDB compliant high performance scalable embedded key-value store

a very simple pure key => value storage system that speaks Redis protocol with Postgres as storage engine and more

⚡ 6.824: Distributed Systems (Spring 2017). A course which present abstractions and implementation techniques for engineering distributed systems.

Simple key-value store abstraction and implementations for Go (Redis, Consul, etcd, bbolt, BadgerDB, LevelDB, Memcached, DynamoDB, S3, PostgreSQL, MongoDB, CockroachDB and many more)

A simple, fast and versatile Datalog database