The point of the database is that you upload application logic into the database as a WebAssembly stored procedure, so instead of clients connecting to a webserver they connect directly to the database. The database itself does authentication and you write your own authorization logic just like you would inside a webserver.
We’ve developed our game, BitCraft (https://bitcraftonline.com) entirely in this way. All of the game state is stored and synchronized with clients via SpacetimeDB, including player positions and movement.
We also plan to allow you to horizontally scale your applications in two ways:
1. By having multiple databases that can send messages to each other (i.e. the actor model) 2. By having distributed databases which partition data over multiple machines, similarly to CockroachDB, although this approach would cause a commensurate increase in latency in accessing data
Curious to hear your thoughts!