KeyDB

KeyDB is Redis with multi-threading bolted on. A fork that adds per-key locking and MVCC for non-blocking reads, pushing throughput to 1 million ops/sec — 2-5x faster than single-threaded Redis on the same hardware. Because it's a fork, every Redis feature, module, and Lua script works unchanged.

Dragonfly is the ground-up rewrite that benchmarks even higher (4M ops/sec) but with less Redis feature compatibility. Valkey is the Linux Foundation's community Redis fork. Garnet is Microsoft's .NET-based alternative with impressive benchmarks.

Use KeyDB if you need more Redis throughput without changing your code or learning a new system. Active replication — multiple nodes accepting writes simultaneously — is a genuine differentiator over standard Redis replication.

The catch: Snapchat acquired KeyDB, and development has stalled since. If long-term maintenance matters to you, Valkey has stronger community backing and a clearer governance model. KeyDB's BSD-3 license is clean, but an unmaintained fork of a fast-moving project is a ticking clock.