user specific topics isn't the right path, conventional wisdom would be that you want < 1000s of topics. It looks like that limit has been changed more recentl

user specific topics isn't the right path, conventional wisdom would be that you want < 1000s of topics. It looks like that limit has been changed more recently: https://stackoverflow.com/questions/32950503/can-i-have-100s-of-thousands-of-topics-in-a-kafka-cluster https://stackoverflow.com/questions/32950503/can-i-have-100s... but I'm still skeptical it's what you want. You'd need a consumer for each of them, you're tracking offsets for all of them. Much more normal would be a single topic here, partitioned on user. You can have 2 consumers then. One that pulls things off and notifies. Another one that pulls things off and stores to the DB, which is indexed by user ID. Then when they read a notification, you flip a bit in the DB for the notifications.