How does Scala support high-throughput financial ledger systems?

Ledger systems use event sourcing, append-only logs, and strict consistency rules.

Financial ledgers in Scala are typically implemented using event sourcing to ensure immutability and auditability. Each transaction is appended to a log and never modified. State is derived by replaying events. Strong consistency is often required, so systems use partitioning and single-writer models per account. Snapshots improve performance for long histories.