Hi 🙂 - there are a lot of angles to this, but I imagine the main reasons for seriously considering Crux over Postgres as things stand today are: - you need simple point-in-time bitemporal queries - you have a need for in-process graph-like queries - you want to use Datalog - you already use Kafka and you don't care for all the bells and whistles in Postgres enough to justify running an extra system - you would like to be able to extend or modify a small modular database that is written in Clojure I don't know enough about Fulcro to comment on that aspect. Any thoughts?

Fulcro is Clojure(Script) framework built on the top of React that uses EQL (similar in scope but more powerful than GraphQL) for it's language of communication with server. At server Pathom is used to parse Queries and Mutations sent from Fulcro client. Fulcro also helps with state management at frontend with it's normalised graph database and provides many other capabilities.

It's most likely a question of what you have available to hand already and whether you have other potential use-cases for introducing either option into your stack. Migrating from JDBC/Postgres to Kafka when you need to scale is definitely plausible and desirable. You could use our Kafka connectors to do this replication