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Database / REDIS

What is Valkey, and how does it relate to Redis?

Valkey is a Linux Foundation-backed, BSD-3-Clause licensed fork of Redis, created immediately after Redis Ltd. moved the core Redis project off the permissive BSD license to a source-available dual license (SSPLv1/RSALv2) in March 2024. Valkey started from the last BSD-licensed Redis release (7.2.4) and has continued developing independently since, with contributions from major cloud vendors and several original Redis engineers, including Redis creator Salvatore Sanfilippo, who has contributed to Valkey.

Redis (current, 8.x line)Valkey
Tri-licensed: AGPLv3 (OSI-approved, added back in Redis 8, May 2025) or source-available SSPLv1/RSALv2.BSD-3-Clause, unrestricted, OSI-approved open source, no copyleft terms.
Maintained by Redis Ltd.Maintained by the Linux Foundation with a broad multi-vendor contributor base.
Adds newer Redis-exclusive features like vector sets (VADD/VSIM).Its own independent roadmap; e.g. Valkey 9.x added multi-database cluster support and atomic slot migration.

The two remain wire-protocol compatible in most respects, so standard client libraries (Jedis, Lettuce, redis-py, and others) generally work against either without code changes, which is why major managed cache services (AWS ElastiCache, Google Cloud Memorystore, among others) now default new deployments to Valkey. For teams choosing between them, the practical question usually comes down to license comfort (BSD vs AGPL/source-available) rather than a meaningful feature gap, since the two have stayed close in core capability even while diverging in governance.

What license does Valkey use, in contrast to Redis's current tri-license option?
Why do most existing Redis client libraries generally work against Valkey without changes?

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