Why deterministic finality matters
On proof-of-work or many proof-of-stake chains, transactions are considered final only after multiple confirmation blocks. Even then, there’s a risk of chain reorganizations that can undo an arbitrary number of blocks and transactions therein. With Arc, a transaction is either unconfirmed or final. There is no intermediate state. Once a transaction is included in a committed block, it cannot be reversed. This allows you to build applications that demand high assurance, especially where financial risk must be minimized and operational standards are strict.Sub-second confirmation
Arc’s consensus engine, Malachite, finalizes blocks in less than one second. For comparison, Ethereum requires 12–15 minutes for finality, and many Layer-2 networks inherit similar delays from their settlement layer. This speed enables use cases that are impractical on slower networks:| Use case | How finality helps |
|---|---|
| Point-of-sale payments | A merchant can confirm payment and release goods without waiting for additional block confirmations. |
| Cross-border settlement | Transfers between counterparties finalize instantly, eliminating the settlement windows that introduce counterparty risk. |
| Institutional clearing | Trades and margin calls settle with immediate certainty, matching the expectations of traditional financial infrastructure. |
| Composable workflows | Multi-step onchain flows (such as swap-then-bridge) can execute sequentially without polling or confirmation delays between steps. |
Developer benefits
Deterministic finality simplifies application design by removing the edge cases that probabilistic chains force you to handle.No reorg handling
You don’t need retry logic, rollback mechanisms, or confirmation-count
thresholds. A confirmed transaction stays confirmed.
Immediate offchain effects
Safely trigger downstream actions (webhooks, database writes, notifications)
as soon as a block is committed, without waiting for additional
confirmations.
Simplified state management
Your application only needs to track two transaction states — pending and
final — rather than tracking a sliding confirmation window.
Enterprise compliance
Settlement finality is auditable and provable, meeting the assurance
requirements of regulated financial institutions.