Thanks:)

Basically users can interact by playing basketball games against each other or by trading players. This sort of interactions are handled with something similar to a TCP handshake, since we must ensure that we end up with a consistent state at the end (e.g. players are traded consistently).

Because of this, it is not easy to have 'real-time' interactions: for example, when challenging each other, players only agree on the initial conditions of the game, which then is simulated independently (and deterministically) on both clients.