In this section, we discuss the architecture and components of OpenWhisk. OpenWhisk is designed to be a rock-solid FaaS platform as it is powering IBM Cloud Function, one of the FaaS production systems already launched by IBM. The key of this rock-solid architecture is Kafka. OpenWhisk cleverly uses Kafka as its backbone to guarantee that every single function request accepted by Kafka will be delivered to the invoker layer. Let's start by looking its overall architecture.