Retry with Exponential Backoff & Error Recovery

Reactive error recovery employs a three-layer stack—timeout, retry, and circuit breaker—where omitting any layer exposes a distinct failure mode. Exponential backoff (1s, 2s, 4s, 8s waits) prevents thundering herds by staggering retries across clients, avoiding secondary outages from simultaneous retry traffic. AWS's Builders' Library recommends capping maximum backoff, adding jitter, and treating retries as requests that must not compound problems for the service being called. Reactor's Flux.retryWhen(Retry.backoff(3, Duration.ofSeconds(1)).maxBackoff(Duration.ofSeconds(30))) builds the same strategy with configurable bounds. catchError and onErrorResume provide fallback stream substitution, matching the Reactive Manifesto's Resilient pillar—failures are contained per component. Kotlin Flow's retry(retries) { cause is IOException } applies conditional logic based on the type of failure.