A microproxy is a kind of edge service that retrieves an incoming request only, and then redirects the request to the corresponding service.

A classic example of this type of edge service involves dealing with Cross-Origin Resource Sharing (CORS), as defined at https://en.wikipedia.org/wiki/Cross-origin_resource_sharing. As you probably know, CORS restricts access to specific resources when they are requested from a domain different from where they reside. You can allow access to the resources on each service, or you can take advantage of an edge server, in order to allow services to be requested from other domains.