integration-contract-safety

To prevent breaking changes in cross-service APIs, enforce machine-readable contracts like OpenAPI or JSON Schema and run CI-based contract tests on every push to catch breakages before deployment. This governs versioning, deprecation signals, and consumer migrations across service boundaries.

Contract testing validates interactions between services using machine-readable schemas to prevent silent failures. You should use it for REST APIs, webhook payloads, and async event schemas whenever code crosses a team or service boundary, ensuring signature verification and schema compatibility.

Verify webhook signatures by enforcing payload signing and validating signatures against expected keys before processing. Handle unknown schema versions by implementing robust versioning and deprecation signaling, allowing consumers to adapt gracefully to new event payload structures.

Yes, this approach supports running Pact or schema-driven contract tests in CI pipelines. It works with OpenAPI and JSON Schema files to validate REST APIs, webhook payloads, and event schemas, blocking merges automatically whenever contract validation fails.

The best way to manage API versioning is to maintain machine-readable contracts with explicit deprecation signals. This provides a structured process for producer migrations and consumer adaptation, ensuring additive changes are distinguished from breaking changes across service boundaries.

Contract tests fail when event payload changes break the machine-readable schema or signature verification. Running schema-driven tests or Pact in CI catches these cross-service boundary violations before deployment, preventing silent breaking changes from reaching production.