What is ESI?
ESI is a standard way to assemble pages. This spec is supported by several reverse proxies.
In your builder, just use it.
In your HTTP responses, just normal ESI tags. If you're working within Rails, give Spackle a try.
Here is an example of a response that would be parsed by EsiForRack
<html> <body> <esi:include src="/helloworld"/> </body> </html>
In this case, a request to /helloworld would be made by EsiForRack to fill in the request. If your application sent: “Hey world” as a response to /helloworld the above example would be interpolated to:
<html> <body> Hey world </body> </html>