CustomResource in Kubernetes allows users to enhance the API with their own types by using CustomResourceDefinitions (CRDs) that include an OpenAPI schema, though this extensibility often involves complex YAML definitions. To simplify the management of CustomResources, the new crd2pulumi tool generates types in any Pulumi-supported language, making it easier to handle the intricacies of CRDs like cert-manager or Istio, which can involve extensive and complex YAML schemas. By using programming languages for defining these types, developers benefit from IDE features such as type checking and autocompletion, reducing errors compared to YAML management. Examples like the CronTab and cert-manager demonstrate how crd2pulumi facilitates the creation and management of CustomResources in different programming languages, offering a more efficient and error-free approach. Pulumi provides a robust platform for managing Kubernetes resources, allowing developers to focus on problem-solving rather than dealing with YAML intricacies.