Interface Definition

An Interface Definition provides a formal declaration of the functions and events that a smart contract exposes to the outside world, without including the implementation details. In the context of financial derivatives, interfaces allow different protocols to interact with each other in a standardized way.

For example, a margin engine can interact with any collateral token that implements the standard token interface, regardless of the token's internal logic. This abstraction is key to the composability of decentralized finance, enabling the creation of "money legos" where different protocols can be combined to build sophisticated financial instruments.

By defining clear interfaces, developers can ensure that their protocols are compatible with existing tools, such as wallets, block explorers, and analytics platforms. It serves as a contract between the protocol and the rest of the ecosystem, specifying exactly what can be expected from the interaction.

A well-defined interface is essential for long-term maintainability and interoperability.