[keycloak-dev] Using Cassandra as storage backend, fully customize admin console

Dear Keycloak Team, Since my architecture is designed to be based on Cassandra for primary storage backend and ElasticSearch for search functionality. Where should I start, if I need to change code base of keycloak to use Cassandra and customize field required for login and registration. For example. I don't want to have "username" field in my registration page. We need only "firstName","lastName","email", "password", and "confirmPassword". I want to custome "keycloak-server.war" to fit with my application. Where can I get start to customize "keycloak-server.war". PS:Using Themes and SPI provide by keycloak is not enough to customize to fit my implementation. Best Regards, Sun Chanras