Seamless wallet
In a seamless (or wallet-callback) model, the game provider's servers call your wallet API for every transaction: debit for bets, credit for wins, reversal for rollbacks. Your platform remains the single source of truth for balances.
Transfer wallet
In a transfer model, the player moves funds into a provider-side balance and plays from it. Fewer calls to your systems, but balances now live in two places and reconciliation becomes a real task.
Idempotency and ordering
Bet and win calls can be retried or arrive out of order. Key every transaction by a unique ID, store processed IDs, and make rollback handling explicit — a rollback for an unknown bet needs a defined answer, not a crash.
Balance consistency
Return the player's resulting balance in every wallet response. Mismatches between your balance and the provider's view are the earliest signal of integration bugs, and monitoring them catches problems before players do.