Contract Testing

Contract Testing verifies that a provider and its consumers agree on an interface without requiring every component to run together in a full end-to-end environment.

Consumer and provider perspectives

A contract captures requests, responses, schemas, events, error behavior, or compatibility expectations. Consumer-driven contract testing records what a consumer relies on, then verifies that the provider continues to satisfy those expectations.

Contract tests complement unit, integration, and end-to-end tests. They are particularly valuable for APIs and event-driven systems where teams deploy independently. They do not replace testing of infrastructure, real network behavior, data stores, or complete user journeys.