Capturing Smart Contract Design with DCR Graphs

Smart contracts manage blockchain assets. While smart contracts embody business processes, their platforms are not process-aware. Mainstream smart contract programming languages such as Solidity do not have explicit notions of roles, action dependencies, and time. Instead, these concepts are implemented in program code. This makes it very hard to design and analyze smart contracts. We argue that DCR graphs are a suitable formalization tool for smart contracts because they explicitly and visually capture these features. We utilize this expressiveness to show that many common high-level design patterns in smart-contract applications can be naturally modeled this way. Applying these patterns shows that DCR graphs facilitate the development and analysis of correct and reliable smart contracts by providing a clear and easy-to-understand specification.