#aurora was much less forgiving with unique constraints than mysql. The schema for one of my utf8mb4 varchars had a max length of 255 and a unique index. It appears mysql silently truncates, whereas aurora complained the index was > 767 bytes. ~ #win
I initially went with the unclustered variants of elasticache and rds. Once I wrapped my head around the topology, #redis cluster mode and #aurora were much easier to work with in #terraform