Knative Build Google started the  Knative  project in 2018 with the aim of bringing advanced application-related functionality to Kubernetes. The basis of Knative is a  service mesh  like Istio, which provides infrastructure services for traffic management, observability, and security out of the box. Service meshes use Sidecars  to instrument applications with infrastructure-related functionality. On top of the service mesh, Knative provides additional services, primarily targeted at application developers: Knative serving For scale-to-zero support for application services, that can be leveraged by Function-as-a-Service platforms, for example. Together with the pattern described in Chapter 24,  Elastic Scale  and the underlying service mesh support, Knative serving enables scaling from zero to arbitrary many replicas. Knative eventing A mechanism for delivering events from sources to sinks through channels. Events can trigger Services used as sinks to scale up from zero. Knative build For compiling an application’s source code to container images within a Kuber‐ netes cluster. A follow-up project is Tekton Pipelines, which will eventually replace Knative build. Both Istio and Knative are implemented with the  Operator  pattern and use CRDs to declare their managed domain resources. In the remaining part of this section, we focus on Knative build as this is Knative’s implementation of the  Image Builder  pattern. Knative build is primarily targeted at tool developers to provide a user interface and seamless build experience to the end user. Here we give a high-level overview of the building blocks of Knative build. The project is rapidly moving and might even be replaced by a follow-up project like Tekton Pipelines but the principle mechan‐ ics are very likely to stay the same. Nevertheless, some details might change in the future, so refer to the example code, which we keep up-to-date with the latest Knative versions and projects. Knative is designed to provide building blocks to integrate with your existing CI/CD solutions. It is not a CI/CD solution for building container images by itself. We expect 230  |  Chapter 25: Image Builder