Your app calls an external API. The API is down. Your code: "I'll keep retrying forever." User: "Your app is frozen." Circuit breaker prevents this. The Pattern Imagine a circuit breaker in your house. When too much current flows, the breaker trips. Cuts the circuit. Prevents fire. Same idea for APIs. States: CLOSED: API works, requests go through OPEN: API is down, requests fail fast (no retry) HALF_OPEN: API might be back, try a test request Flow: Request → API works → CLOSED (pass through) Request → API fails → count failures Failures > threshold → OPEN (fail fast, no retry) Wait 30 seconds → HALF_OPEN (test request) Test succeeds → CLOSED (back to normal) Test fails → OPEN (not ready yet) Enter fullscreen mode Exit fullscreen mode Why This Matters Without circuit breaker: API is down. Code: "Try again" Code: "Try again" Code: "Try again" (30 seconds of retries) User: "Your app is broken" Enter fullscreen mode Exit fullscreen mode With circuit breaker: API is down.…