Key Changes
Pact v16.5.0, a minor update released on May 24, 2026, brings significant enhancements for contract testing. A major feature is the addition of HTTP response status code matching support, allowing more precise contract definitions. Furthermore, Pact V4 now includes XML body matching capabilities, expanding its utility for services using XML payloads.
Several important fixes and improvements are also part of this release. Compatibility with Apollo/node-fetch v3 has been resolved, addressing a GraphQL peer dependency conflict. Type definitions for synchronousBodyHandler and asynchronousBodyHandler now allow for narrower body types, improving developer experience. The update also ensures the CORS option is correctly passed to the mock server transport in Pact V3, defaulting to true. Dependency updates include https-proxy-agent to v9.
For a detailed list of changes, refer to the official changelog.
Impact for QA Teams
This update directly benefits QA engineers by providing more granular control over contract definitions, especially for HTTP status codes and XML-based APIs. Improved compatibility with popular libraries like Apollo and clearer type definitions will streamline test automation workflows, reducing setup time and potential debugging efforts.
