Hi there!
If we got your use case correctly, you are looking for a web server component that is a library/API that you could load to into your windows service process and serve pages from there. If that's the case, UWS won't fit the bill. UWS is always its own process - either a service or an interactive application. Old Microsoft Cassini examples are actually libraries that can be loaded in-process and could be useful for your purposes.
The downside to this approach is that faltering web application running in the same process as your service, may take down your entire service if web app fails. To prevent it from happening you may want to have a .Net Remoting interface in your services, so then external applications, like a web app, could run in outside process (in UWS, for example or Windows program) and could talk to it, w/o jeopardizing main service's uptime.
Best regards,
UltiDev Team.
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