Reusability vs customization

[eluser]jnorris441[/eluser]
My boss is one of those guys who wants to make all of the code in one site, and have all the sites run off of that one base site.

That tends to make my life hell, because instead of copying the code and modifying it for each custom site, I have to code all the custom stuff together and it gets messy. Matchbox sounded good, but copying the modules from site to site is what I need to avoid. Is there something out there that would let me have customizations per site, otherwise use a default controller?

I know I can accomplish this by creating a library for everything and creating a new CI site for every domain, but when I add features to the application it would be a lot of work to go in and add it for each site since they would be separate at that point. Since the Code Igniter events aren't contained in libraries but in the controllers, that means I would need to have a shared base controller for all these sites for me to add features to, and then for each site extend that controller for any custom stuff.

Anyone run into this sort of thing?