canton-ledger-model
Installation
SKILL.md
Canton Ledger Model
Overview
Canton uses an extended UTXO (eUTXO) model: the ledger is a collection of active contracts, not mutable account balances. Each contract is created by a transaction, is immutable, has a unique contract ID, and exists until archived by another transaction. This model underpins Canton's privacy, parallelism, and composability.
Contracts as UTXOs
Why eUTXO over an account model:
| Property | eUTXO | Account model |
|---|---|---|
| Parallelism | High — independent contracts process in parallel | Low — account locks |
| Privacy | Natural — each contract has specific stakeholders | Hard — accounts aggregate data |
| Composability | Built-in — contracts reference each other | Needs careful design |
| Double-spend prevention | Structural — a contract is archived once | Needs sequence numbers |
Lifecycle: Create → Active → (Archive / consuming Exercise) → Archived. Archived contracts no longer exist on the ledger (historical only).