Circuit Breaker Simulator — Interactive System Design Lab

Watch a circuit breaker trip as downstream errors accumulate, enter half-open state to test recovery, and return to closed when the service is healthy. Use auto-send mode to drive traffic automatically and watch the breaker open under sustained failure. Understand why circuit breakers are essential in microservice fault tolerance.

Trip the breaker with auto-send, watch half-open recovery, and understand cascading failure protection.

This free interactive simulation runs directly in your browser — no account needed. Adjust the parameters and watch how the system responds in real time.

Concepts covered

  • circuit breaker
  • fault tolerance
  • resilience
  • microservices
  • failure handling
  • half-open
  • cascading failure
  • bulkhead pattern

Read the guide

  • Security — Security is not a feature; it is the foundation. Master AuthN vs AuthZ, the endless Session vs JWT debate, and how to define against the OWASP Top 10.
  • Distributed System Patterns — Microservices break things: Transactions, Consistency, and Reliability. Learn the patterns (Circuit Breaker, Saga, Outbox) we use to glue them back together.

Related articles

  • How to Answer Any System Design Question — A step-by-step framework for tackling any system design interview question — requirements, estimation, high-level design, and deep dives — with a full worked example (Design a URL shortener) and the phrases interviewers listen for.