How to integrate Template published as web applications with the web applications that use this wrapper?

I have the following case :

My current projects are like that :

A master page and set of pages.aspx inherit the layout from the master page.

Now I want to Make it on large scale . So what i want to do is :

Two types of projects published as two separate web applications(Loosely Coupled) :

1. The wrapper (the main general template for all other web
   applications) replace (the master page which used in the same
   application),this project used as a framework or template like this :(Header,Footer), [(Sidebar(Menu),Body) dynamic according to the web application which use the wrapper]

2. Any web application will fill the wrapper in two parts (The body and The menu) dynamically

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How to integrate the wrapper and the web applications which should use this wrapper and both of them published as two separate web applications ?