You can use the following resources to build service brokers and routing services:
Custom services overview topic gives a high-level description of how service brokers work in VMware Tanzu Application Service for VMs (TAS for VMs).
The Service broker API topic gives a more detailed explanation of TAS for VMs service brokers, and provides a full specification for the endpoints, requests, responses, and status codes that a service broker must support.
Example service brokers topic offers example brokers written in Ruby, Java, and Go.
Supporting multiple TAS for VMs instances topic has information about registering a service broker with multiple TAS for VMs instances.
Route services explains how route services work, and what are the different architectures for using them in a TAS for VMs deployment.
Example route services gives examples of a logging route service, a rate-limiting route service, and another logging service written in Spring Boot. It also offers a tutorial on setting up the logging route service.