Codeigniter + Doctrine architecture

I am building a system based on C开发者_如何学运维odeigniter + Doctrine.

The system will have three access points.

Backend side, Customer Side and Websevice Side. (Each side is a CI application folder)

I am creating the CRUDS under the Backend/models

I want to reuse it in the other CI applications folders.

What is the best architecture for that?

Should i make it loosely coupled in the webservice side and let the other apps connect to it?

Thanks

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Each is a seperate CI application? Seems a little extreme, seeing as components of one could be used by others (eg. libraries, models, etc). I would recommend making it more modular, check out Modular Extensions - HMVC.