This article was originally published on AI Study Room . For the full version with working code examples and related articles, visit the original post. Contract Testing Contract Testing Contract testing is a testing methodology that validates the interactions between services against a shared agreement. Unlike integration tests that run both services together, contract tests verify each service independently against a contract that defines their interaction. This approach catches integration issues early and enables independent deployment of services. Consumer-Driven Contracts Consumer-driven contracts (CDC) follow the principle that consumers define their expectations from a provider. The consumer writes a contract specifying how it intends to use the provider's API—which endpoints it calls, what data it sends, and what responses it expects. The provider verifies that it meets all consumer contracts. This approach ensures that providers do not break existing consumers when they change their API.…