Hi anda_skoa, thanks for your quick reply.

I apologize for not explaining this detail of relationship between libraries.

The php library depends on the core library within the subproject language. That's where the problem comes to me.

Answering your question, yes. As you can see in php.pro, in the INCLUDEPATH is the core library on which it depends, where the model directory is part of core.

Regarding the circular dependency, yes, I know that I have it, and I have to solve that inconsistency, but it's because I have a test code and implemented it directly in a project base class to test the operation and see how to decouple that section of code .