Retry, timeout, and circuit breaker

Scenario

A checkout API must protect itself from a slow or failing payment provider. The diagram makes the resilience policy reviewable: the gateway checks the breaker, retries bounded attempts, records timeouts, and falls back to asynchronous recovery instead of blocking the customer forever.

Annotation key

• loop (1,3) documents the bounded retry policy.
• alt separates fast responses, timeouts, and open-breaker rejection.
• break [authorized] exits the retry loop once a successful authorization arrives.
• ->> marks asynchronous fallback work queued outside the request path.