The disclosed technology is generally directed to secure transactions. In one example of the technology, a smart contract is generated based at least in part on a schema and provided information. The smart contract may be caused to be deployed on a ledger as a smart contract ledger instance. A unique address associated with the deployed smart contract ledger instance may be received. A cryptlet binding for a first contract cryptlet that is associated with the smart contract ledger instance may be generated. The cryptlet binding may be sent to the first contract cryptlet. Responsive to a state change associated with the first contract cryptlet, an update may be communicated to the smart contract ledger instance.