Blockchain platforms such as Ethereum and Hyperledger facilitate transactions between parties that have not established trust. Increased interest in these platforms has motivated the design of programming languages such as Solidity, which allow users to create blockchain programs. However, there have been several recent instances where Solidity programs have contained bugs that have been exploited. The security of blockchain programs is especially important given that they commonly involve the exchange of money or other objects with real-world value. We are currently developing a blockchain-based programming language called Obsidian with the goal of minimizing the risk of common security vulnerabilities. We are designing this language in a human-centered way, conducting exploratory user studies with a natural programming approach to inform our design choices. In this paper, we discuss our approach to the design of a user study, as well as our preliminary findings.