[miraculixx]

KeyDB, a multithreaded drop-in replacement for Redis, under MIT, owned by Snap.

https://docs.keydb.dev/

[stephenr]

I realise they use the term "drop in replacement", but without Lua support it really isn't.

That doesn't mean it isn't worth exploring but lacking a major piece of functionality means it explicitly can't be "dropped in" to replace redis.