An example operation may include one or more of defining a target specification for a blockchain smart contract, obtaining a plurality of reusable smart contracts, and creating the blockchain smart contract. Creating the blockchain smart contract includes combining the plurality of reusable smart contracts and the target specification into a first set of contracts, transforming the first set of contracts into a second set of contracts, selecting a target contract from the second set of contracts, and translating the target contract into an executable form of the blockchain smart contract. The target specification includes a regular event pattern and a temporal constraint the blockchain smart contract must satisfy. Each of the reusable smart contracts includes a reusable event pattern.