I'm glad you brought up the migration, because one of the main goals behind our project is to automate migrating to a sharded deployment. You can think of your DB as the base case (num_shards = 1), and PgDog as the recursive solution.
Automatic data transfer would be super cool to get out of the box. We had a custom multi-tenancy solution for our application that heavily used PostgreSQL schemas. One schema for each customer.
It was a pain to get that work with Cockroach since it doesn’t optimize cross schema queries and suggests one DB per customer. This was a deal breaker for us and we had to duplicate data to avoid cross schema queries.
Being able to live within Postgres has its advantages.
