To go along with the MySQL (https://tinoest.co.uk/releases/MySQLCache.zip) and PostgreSQL (https://tinoest.co.uk/releases/PostgreSQLCache.zip) Cache's I have as modifications I now also have a Redis (https://tinoest.co.uk/releases/RedisCache.zip) based one.
It's available here, https://tinoest.co.uk/releases/RedisCache.zip
Any issues please let me know. It currently expects a port and ip for it to work. I will look at the socket based option at some point.
I can confirm Redis cache is working on Elkarte 1.1.7. and with the latest Redis 6.2.0