Implementations of the present specification include receiving, from a client in a blockchain network, a request to execute a workflow program, wherein the workflow program is stored in a blockchain maintained by the blockchain network; identifying an operation associated with the workflow program; assigning the identified operation to a subset of the plurality of nodes in the blockchain network, wherein each node is configured to execute the operation separately from the other nodes in the subset of nodes; identifying processing results for the executed operation associated with nodes in the subset of nodes, each processing result associated with a particular node from the subset and representing a result of the executed operation produced by the particular node; and determining a consensus result for the operation based on the identified processing results associated with a number of nodes greater than or equal to a consensus threshold matching the consensus result.