Contract Testing Essentials (Pact)

• Store consumer contracts beside the integration specs that generate them; version contracts semantically and publish on every CI run.
• Require provider verification before merge; failed verification blocks release and surfaces breaking changes immediately.
• Capture fallback behaviour inside interactions (timeouts, retries, error payloads) so resilience guarantees remain explicit.
• Automate broker housekeeping: tag releases, archive superseded contracts, and expire unused pacts to reduce noise.
• Pair contract suites with API smoke or component tests to validate data mapping and UI rendering in tandem.

Source: Pact consumer/provider sample repos, Murat contract testing blog.