In this article, we dissect the complex interplay between law and technology in the derivatives market and describe an approach for developing modular, smart contracts. We draw parallels between legal prose and programming, advocating for a formalised approach to contract drafting that accommodates smart contract technology. The Common Domain Model is identified as a pivotal tool, providing a standardised representation of contractual terms that ensures clarity and consistency across the industry. Using this standard framework, we demonstrate how to embed traditional contracts within a modular, composable smart contract architecture.