Crankless settlement means a trading protocol completes its own state updates, such as settling matched trades, inside the transactions that users already send. Many onchain protocols instead need someone to submit a separate transaction, often called a crank, to move the protocol forward. The bots that send those transactions are called keepers. A crankless design removes that dependency, so settlement does not wait for an outside party to act.
Last updated: November 2, 2026.
Why do some protocols need a crank?
Smart contracts do not run on their own. They execute only when a transaction calls them. Any work that should happen later, or when a condition is met, needs someone to send a transaction at the right time. The name comes from turning a crank to push a machine one step forward.
| Task | Why it needs a trigger |
|---|---|
| Settling matched orders | In queue-based designs, filled trades wait until a transaction moves them to balances |
| Liquidations | A position below its margin requirement stays open until someone acts |
| Funding payments | When funding is pushed to every account on a schedule, each payment needs a transaction |
| Price updates | Some oracle designs post a new price only when someone submits it |
| Triggered orders | A stop order needs a transaction once the trigger price is reached |
Keepers can be run by the protocol team, by third parties, or by anyone. Protocols usually pay them a fee or reward for each useful transaction.
How does crankless settlement work?
A crankless protocol folds the follow-up work into transactions that happen anyway. Common approaches:
- Settle in the same transaction: when an incoming order matches, the same transaction updates the balances of both sides, so there is no queue to clear later.
- Update on next use: values that build up over time, such as funding, are calculated when an account is next touched, instead of being pushed to every account on a schedule.
What are the trade-offs?
Removing the crank removes a moving part. Settlement no longer depends on keepers being online, paid enough to act, or able to get their transactions included when the network is busy. Users see their balances update when their trade does.
The cost is that each user transaction does more work, which can make it more expensive. Some tasks, such as liquidations, may still rely on an outside party in a design that settles trades without a crank. The guide to crypto exchange backends shows where settlement sits among the other systems a venue runs.
FAQ
Is a keeper the same as a crank?
No. The crank is the function or transaction that moves the protocol forward. A keeper is the bot or operator that sends it.
Is a keeper the same as an oracle?
No. An oracle supplies outside data, such as a price. A keeper triggers actions inside the protocol. Some systems use keepers to post oracle updates, which is why the roles are sometimes confused.
Does crankless mean the venue is fully onchain?
Not necessarily. Crankless describes how state updates are triggered, not where orders are matched. The comparison of order books and AMMs explains the main ways trades are matched.
Build trading across chains
For tools to build applications that work across chains, see LayerZero developer resources.