Kubernetes in general, and Istio in particular, have changed a lot the way we look at Ops-related constraints: monitoring, load-balancing, health checks, etc. Before those products became available, there were already available solutions to handle those constraints. Among them is Hystrix, a Java library provided by Netflix. In particular, Hystrix provides an implementation of the Circuit Breaker pattern, which prevents a network or service failure from cascading to other services. But now Istio also provides the same capability. In this talk, we will have a look at how Istio and Hystrix implement the Circuit Breaker pattern, and what pros/cons each of them has.