[maffydub]

I believe that Redis supports CRDTs (https://redis.com/blog/diving-into-crdts/) for its active/active geo-replication, and they're supposed to be pretty fast.

...but it's important to note that CRDTs as used by Redis (and as defined by, for example, https://arxiv.org/pdf/1806.10254.pdf) really just means that you've defined a way to consistently resolve conflicts - it doesn't necessarily mean the all-singing-all-dancing collaborative text editing that a lot of people seem to be assuming. For example, as defined in the paper above, simple "last write wins" is a CRDT.