Explain the Circuit Breaker pattern.

Updated Apr 28, 2026

Short answer

A design pattern used to detect failures and encapsulate the logic of preventing a failure from constantly recurring.

Deep explanation

As systems scale, maintaining consistency and resilience becomes harder. Patterns like Sagas manage distributed transactions without traditional locks. Circuit breakers prevent cascading failures by 'tripping' when a service is unhealthy, allowing it time to recover.

Real-world example

Netflix uses Hystrix/Resilience4j to ensure that if the 'Recommendations' service is slow, the user still sees their 'Watchlist'.

Common mistakes

  • Implementing Sagas for every simple cross-service operation.

Follow-up questions

  • What is a 'fallback' method?
  • How do you handle data consistency in Sagas?

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