Circuit Breaker Pattern

Summary

A pattern that stops calling a failing downstream service after repeated failures, failing fast instead of piling up slow, doomed requests — preventing one failing service from cascading into a system-wide outage.

• 1Diagram the three circuit breaker states: closed, open, half-open.
• 2Implement a basic circuit breaker around a flaky external API call.
• 3Understand this pattern specifically prevents cascading failures across services.