Digital or “smart” contracts execute in a blockchain environment. Any entity (whether public or private) may specify a digital contract via a contract identifier in a blockchain. Because there may be many digital contracts offered as virtual services, the contract identifier uniquely identifies a particular digital contract offered by a virtual machine, vendor or supplier. The blockchain is thus not burdened with the programming code that is required to execute the digital contract. The blockchain need only include or specify the contract identifier (and perhaps one or more contractual parameters), thus greatly simplifying the blockchain and reducing its size (in bytes) and processing requirements.